java.lang
Class ClassLoader

java.lang.Object sample code for java.lang.Object definition code for java.lang.Object 
  extended by java.lang.ClassLoader
Direct Known Subclasses:
SecureClassLoader sample code for java.security.SecureClassLoader definition code for java.security.SecureClassLoader

public abstract class ClassLoader
extends Object sample code for java.lang.Object definition code for java.lang.Object

A class loader is an object that is responsible for loading classes. The class ClassLoader is an abstract class. Given the binary name of a class, a class loader should attempt to locate or generate data that constitutes a definition for the class. A typical strategy is to transform the name into a file name and then read a "class file" of that name from a file system.

Every Class sample code for java.lang.Class definition code for java.lang.Class object contains a reference sample code for java.lang.Class.getClassLoader() definition code for java.lang.Class.getClassLoader() to the ClassLoader that defined it.

Class objects for array classes are not created by class loaders, but are created automatically as required by the Java runtime. The class loader for an array class, as returned by Class.getClassLoader() sample code for java.lang.Class.getClassLoader() definition code for java.lang.Class.getClassLoader() is the same as the class loader for its element type; if the element type is a primitive type, then the array class has no class loader.

Applications implement subclasses of ClassLoader in order to extend the manner in which the Java virtual machine dynamically loads classes.

Class loaders may typically be used by security managers to indicate security domains.

The ClassLoader class uses a delegation model to search for classes and resources. Each instance of ClassLoader has an associated parent class loader. When requested to find a class or resource, a ClassLoader instance will delegate the search for the class or resource to its parent class loader before attempting to find the class or resource itself. The virtual machine's built-in class loader, called the "bootstrap class loader", does not itself have a parent but may serve as the parent of a ClassLoader instance.

Normally, the Java virtual machine loads classes from the local file system in a platform-dependent manner. For example, on UNIX systems, the virtual machine loads classes from the directory defined by the CLASSPATH environment variable.

However, some classes may not originate from a file; they may originate from other sources, such as the network, or they could be constructed by an application. The method defineClass sample code for java.lang.ClassLoader.defineClass(java.lang.String, byte[], int, int) definition code for java.lang.ClassLoader.defineClass(java.lang.String, byte[], int, int) converts an array of bytes into an instance of class Class. Instances of this newly defined class can be created using Class.newInstance sample code for java.lang.Class.newInstance() definition code for java.lang.Class.newInstance() .

The methods and constructors of objects created by a class loader may reference other classes. To determine the class(es) referred to, the Java virtual machine invokes the loadClass sample code for java.lang.ClassLoader.loadClass(java.lang.String) definition code for java.lang.ClassLoader.loadClass(java.lang.String) method of the class loader that originally created the class.

For example, an application could create a network class loader to download class files from a server. Sample code might look like:

   ClassLoader loader = new NetworkClassLoader(host, port);
   Object main = loader.loadClass("Main", true).newInstance();
          . . .
 

The network class loader subclass must define the methods findClass sample code for java.lang.ClassLoader.findClass(java.lang.String) definition code for java.lang.ClassLoader.findClass(java.lang.String) and loadClassData to load a class from the network. Once it has downloaded the bytes that make up the class, it should use the method defineClass sample code for java.lang.ClassLoader.defineClass(byte[], int, int) definition code for java.lang.ClassLoader.defineClass(byte[], int, int) to create a class instance. A sample implementation is:

     class NetworkClassLoader extends ClassLoader {
         String host;
         int port;

         public Class findClass(String name) {
             byte[] b = loadClassData(name);
             return defineClass(name, b, 0, b.length);
         }

         private byte[] loadClassData(String name) {
             // load the class data from the connection
              . . .
         }
     }
 

Binary names

Any class name provided as a String sample code for java.lang.String definition code for java.lang.String parameter to methods in ClassLoader must be a binary name as defined by the Java Language Specification.

Examples of valid class names include:

   "java.lang.String"
   "javax.swing.JSpinner$DefaultEditor"
   "java.security.KeyStore$Builder$FileBuilder$1"
   "java.net.URLClassLoader$3$1"
 

Since:
1.0
See Also:
resolveClass(Class) sample code for java.lang.ClassLoader.resolveClass(java.lang.Class) definition code for java.lang.ClassLoader.resolveClass(java.lang.Class)

Constructor Summary
protected ClassLoader sample code for java.lang.ClassLoader.ClassLoader() definition code for java.lang.ClassLoader.ClassLoader() ()
          Creates a new class loader using the ClassLoader returned by the method getSystemClassLoader() sample code for java.lang.ClassLoader.getSystemClassLoader() definition code for java.lang.ClassLoader.getSystemClassLoader() as the parent class loader.
protected ClassLoader sample code for java.lang.ClassLoader.ClassLoader(java.lang.ClassLoader) definition code for java.lang.ClassLoader.ClassLoader(java.lang.ClassLoader) (ClassLoader sample code for java.lang.ClassLoader definition code for java.lang.ClassLoader  parent)
          Creates a new class loader using the specified parent class loader for delegation.
 
Method Summary
 void clearAssertionStatus sample code for java.lang.ClassLoader.clearAssertionStatus() definition code for java.lang.ClassLoader.clearAssertionStatus() ()
          Sets the default assertion status for this class loader to false and discards any package defaults or class assertion status settings associated with the class loader.
protected  Class sample code for java.lang.Class definition code for java.lang.Class <?> defineClass sample code for java.lang.ClassLoader.defineClass(byte[], int, int) definition code for java.lang.ClassLoader.defineClass(byte[], int, int) (byte[] b, int off, int len)
          Deprecated. Replaced by defineClass(String, byte[], int, int) sample code for java.lang.ClassLoader.defineClass(java.lang.String, byte[], int, int) definition code for java.lang.ClassLoader.defineClass(java.lang.String, byte[], int, int)
protected  Class sample code for java.lang.Class definition code for java.lang.Class <?> defineClass sample code for java.lang.ClassLoader.defineClass(java.lang.String, byte[], int, int) definition code for java.lang.ClassLoader.defineClass(java.lang.String, byte[], int, int) (String sample code for java.lang.String definition code for java.lang.String  name, byte[] b, int off, int len)
          Converts an array of bytes into an instance of class Class.
protected  Class sample code for java.lang.Class definition code for java.lang.Class <?> defineClass sample code for java.lang.ClassLoader.defineClass(java.lang.String, byte[], int, int, java.security.ProtectionDomain) definition code for java.lang.ClassLoader.defineClass(java.lang.String, byte[], int, int, java.security.ProtectionDomain) (String sample code for java.lang.String definition code for java.lang.String  name, byte[] b, int off, int len, ProtectionDomain sample code for java.security.ProtectionDomain definition code for java.security.ProtectionDomain  protectionDomain)
          Converts an array of bytes into an instance of class Class, with an optional ProtectionDomain.
protected  Class sample code for java.lang.Class definition code for java.lang.Class <?> defineClass sample code for java.lang.ClassLoader.defineClass(java.lang.String, java.nio.ByteBuffer, java.security.ProtectionDomain) definition code for java.lang.ClassLoader.defineClass(java.lang.String, java.nio.ByteBuffer, java.security.ProtectionDomain) (String sample code for java.lang.String definition code for java.lang.String  name, ByteBuffer sample code for java.nio.ByteBuffer definition code for java.nio.ByteBuffer  b, ProtectionDomain sample code for java.security.ProtectionDomain definition code for java.security.ProtectionDomain  protectionDomain)
          Converts a ByteBuffer sample code for java.nio.ByteBuffer definition code for java.nio.ByteBuffer into an instance of class Class, with an optional ProtectionDomain.
protected  Package sample code for java.lang.Package definition code for java.lang.Package definePackage sample code for java.lang.ClassLoader.definePackage(java.lang.String, java.lang.String, java.lang.String, java.lang.String, java.lang.String, java.lang.String, java.lang.String, java.net.URL) definition code for java.lang.ClassLoader.definePackage(java.lang.String, java.lang.String, java.lang.String, java.lang.String, java.lang.String, java.lang.String, java.lang.String, java.net.URL) (String sample code for java.lang.String definition code for java.lang.String  name, String sample code for java.lang.String definition code for java.lang.String  specTitle, String sample code for java.lang.String definition code for java.lang.String  specVersion, String sample code for java.lang.String definition code for java.lang.String  specVendor, String sample code for java.lang.String definition code for java.lang.String  implTitle, String sample code for java.lang.String definition code for java.lang.String  implVersion, String sample code for java.lang.String definition code for java.lang.String  implVendor, URL sample code for java.net.URL definition code for java.net.URL  sealBase)
          Defines a package by name in this ClassLoader.
protected  Class sample code for java.lang.Class definition code for java.lang.Class <?> findClass sample code for java.lang.ClassLoader.findClass(java.lang.String) definition code for java.lang.ClassLoader.findClass(java.lang.String) (String sample code for java.lang.String definition code for java.lang.String  name)
          Finds the class with the specified binary name.
protected  String sample code for java.lang.String definition code for java.lang.String findLibrary sample code for java.lang.ClassLoader.findLibrary(java.lang.String) definition code for java.lang.ClassLoader.findLibrary(java.lang.String) (String sample code for java.lang.String definition code for java.lang.String  libname)
          Returns the absolute path name of a native library.
protected  Class sample code for java.lang.Class definition code for java.lang.Class <?> findLoadedClass sample code for java.lang.ClassLoader.findLoadedClass(java.lang.String) definition code for java.lang.ClassLoader.findLoadedClass(java.lang.String) (String sample code for java.lang.String definition code for java.lang.String  name)
          Returns the class with the given binary name if this loader has been recorded by the Java virtual machine as an initiating loader of a class with that binary name.
protected  URL sample code for java.net.URL definition code for java.net.URL findResource sample code for java.lang.ClassLoader.findResource(java.lang.String) definition code for java.lang.ClassLoader.findResource(java.lang.String) (String sample code for java.lang.String definition code for java.lang.String  name)
          Finds the resource with the given name.
protected  Enumeration sample code for java.util.Enumeration definition code for java.util.Enumeration <URL sample code for java.net.URL definition code for java.net.URL > findResources sample code for java.lang.ClassLoader.findResources(java.lang.String) definition code for java.lang.ClassLoader.findResources(java.lang.String) (String sample code for java.lang.String definition code for java.lang.String  name)
          Returns an enumeration of URL sample code for java.net.URL definition code for java.net.URL objects representing all the resources with the given name.
protected  Class sample code for java.lang.Class definition code for java.lang.Class <?> findSystemClass sample code for java.lang.ClassLoader.findSystemClass(java.lang.String) definition code for java.lang.ClassLoader.findSystemClass(java.lang.String) (String sample code for java.lang.String definition code for java.lang.String  name)
          Finds a class with the specified binary name, loading it if necessary.
protected  Package sample code for java.lang.Package definition code for java.lang.Package getPackage sample code for java.lang.ClassLoader.getPackage(java.lang.String) definition code for java.lang.ClassLoader.getPackage(java.lang.String) (String sample code for java.lang.String definition code for java.lang.String  name)
          Returns a Package that has been defined by this class loader or any of its ancestors.
protected  Package sample code for java.lang.Package definition code for java.lang.Package [] getPackages sample code for java.lang.ClassLoader.getPackages() definition code for java.lang.ClassLoader.getPackages() ()
          Returns all of the Packages defined by this class loader and its ancestors.
 ClassLoader sample code for java.lang.ClassLoader definition code for java.lang.ClassLoader getParent sample code for java.lang.ClassLoader.getParent() definition code for java.lang.ClassLoader.getParent() ()
          Returns the parent class loader for delegation.
 URL sample code for java.net.URL definition code for java.net.URL getResource sample code for java.lang.ClassLoader.getResource(java.lang.String) definition code for java.lang.ClassLoader.getResource(java.lang.String) (String sample code for java.lang.String definition code for java.lang.String  name)
          Finds the resource with the given name.
 InputStream sample code for java.io.InputStream definition code for java.io.InputStream getResourceAsStream sample code for java.lang.ClassLoader.getResourceAsStream(java.lang.String) definition code for java.lang.ClassLoader.getResourceAsStream(java.lang.String) (String sample code for java.lang.String definition code for java.lang.String  name)
          Returns an input stream for reading the specified resource.
 Enumeration sample code for java.util.Enumeration definition code for java.util.Enumeration <URL sample code for java.net.URL definition code for java.net.URL > getResources sample code for java.lang.ClassLoader.getResources(java.lang.String) definition code for java.lang.ClassLoader.getResources(java.lang.String) (String sample code for java.lang.String definition code for java.lang.String  name)
          Finds all the resources with the given name.
static ClassLoader sample code for java.lang.ClassLoader definition code for java.lang.ClassLoader getSystemClassLoader sample code for java.lang.ClassLoader.getSystemClassLoader() definition code for java.lang.ClassLoader.getSystemClassLoader() ()
          Returns the system class loader for delegation.
static URL sample code for java.net.URL definition code for java.net.URL getSystemResource sample code for java.lang.ClassLoader.getSystemResource(java.lang.String) definition code for java.lang.ClassLoader.getSystemResource(java.lang.String) (String sample code for java.lang.String definition code for java.lang.String  name)
          Find a resource of the specified name from the search path used to load classes.
static InputStream sample code for java.io.InputStream definition code for java.io.InputStream getSystemResourceAsStream sample code for java.lang.ClassLoader.getSystemResourceAsStream(java.lang.String) definition code for java.lang.ClassLoader.getSystemResourceAsStream(java.lang.String) (String sample code for java.lang.String definition code for java.lang.String  name)
          Open for reading, a resource of the specified name from the search path used to load classes.
static Enumeration sample code for java.util.Enumeration definition code for java.util.Enumeration <URL sample code for java.net.URL definition code for java.net.URL > getSystemResources sample code for java.lang.ClassLoader.getSystemResources(java.lang.String) definition code for java.lang.ClassLoader.getSystemResources(java.lang.String) (String sample code for java.lang.String definition code for java.lang.String  name)
          Finds all resources of the specified name from the search path used to load classes.
 Class sample code for java.lang.Class definition code for java.lang.Class <?> loadClass sample code for java.lang.ClassLoader.loadClass(java.lang.String) definition code for java.lang.ClassLoader.loadClass(java.lang.String) (String sample code for java.lang.String definition code for java.lang.String  name)
          Loads the class with the specified binary name.
protected  Class sample code for java.lang.Class definition code for java.lang.Class <?> loadClass sample code for java.lang.ClassLoader.loadClass(java.lang.String, boolean) definition code for java.lang.ClassLoader.loadClass(java.lang.String, boolean) (String sample code for java.lang.String definition code for java.lang.String  name, boolean resolve)
          Loads the class with the specified binary name.
protected  void resolveClass sample code for java.lang.ClassLoader.resolveClass(java.lang.Class) definition code for java.lang.ClassLoader.resolveClass(java.lang.Class) (Class sample code for java.lang.Class definition code for java.lang.Class <?> c)
          Links the specified class.
 void setClassAssertionStatus sample code for java.lang.ClassLoader.setClassAssertionStatus(java.lang.String, boolean) definition code for java.lang.ClassLoader.setClassAssertionStatus(java.lang.String, boolean) (String sample code for java.lang.String definition code for java.lang.String  className, boolean enabled)
          Sets the desired assertion status for the named top-level class in this class loader and any nested classes contained therein.
 void setDefaultAssertionStatus sample code for java.lang.ClassLoader.setDefaultAssertionStatus(boolean) definition code for java.lang.ClassLoader.setDefaultAssertionStatus(boolean) (boolean enabled)
          Sets the default assertion status for this class loader.
 void setPackageAssertionStatus sample code for java.lang.ClassLoader.setPackageAssertionStatus(java.lang.String, boolean) definition code for java.lang.ClassLoader.setPackageAssertionStatus(java.lang.String, boolean) (String sample code for java.lang.String definition code for java.lang.String  packageName, boolean enabled)
          Sets the package default assertion status for the named package.
protected  void setSigners sample code for java.lang.ClassLoader.setSigners(java.lang.Class, java.lang.Object[]) definition code for java.lang.ClassLoader.setSigners(java.lang.Class, java.lang.Object[]) (Class sample code for java.lang.Class definition code for java.lang.Class <?> c, Object sample code for java.lang.Object definition code for java.lang.Object [] signers)
          Sets the signers of a class.
 
Methods inherited from class java.lang.Object sample code for java.lang.Object definition code for java.lang.Object
clone sample code for java.lang.Object.clone() definition code for java.lang.Object.clone() , equals sample code for java.lang.Object.equals(java.lang.Object) definition code for java.lang.Object.equals(java.lang.Object) , finalize sample code for java.lang.Object.finalize() definition code for java.lang.Object.finalize() , getClass sample code for java.lang.Object.getClass() definition code for java.lang.Object.getClass() , hashCode sample code for java.lang.Object.hashCode() definition code for java.lang.Object.hashCode() , notify sample code for java.lang.Object.notify() definition code for java.lang.Object.notify() , notifyAll sample code for java.lang.Object.notifyAll() definition code for java.lang.Object.notifyAll() , toString sample code for java.lang.Object.toString() definition code for java.lang.Object.toString() , wait sample code for java.lang.Object.wait() definition code for java.lang.Object.wait() , wait sample code for java.lang.Object.wait(long) definition code for java.lang.Object.wait(long) , wait sample code for java.lang.Object.wait(long, int) definition code for java.lang.Object.wait(long, int)
 

Constructor Detail

ClassLoader sample code for java.lang.ClassLoader(java.lang.ClassLoader) definition code for java.lang.ClassLoader(java.lang.ClassLoader)

protected ClassLoader(ClassLoader sample code for java.lang.ClassLoader definition code for java.lang.ClassLoader  parent)
Creates a new class loader using the specified parent class loader for delegation.

If there is a security manager, its checkCreateClassLoader sample code for java.lang.SecurityManager.checkCreateClassLoader() definition code for java.lang.SecurityManager.checkCreateClassLoader() method is invoked. This may result in a security exception.

Parameters:
parent - The parent class loader
Throws:
SecurityException sample code for java.lang.SecurityException definition code for java.lang.SecurityException - If a security manager exists and its checkCreateClassLoader method doesn't allow creation of a new class loader.
Since:
1.2

ClassLoader sample code for java.lang.ClassLoader() definition code for java.lang.ClassLoader()

protected ClassLoader()
Creates a new class loader using the ClassLoader returned by the method getSystemClassLoader() sample code for java.lang.ClassLoader.getSystemClassLoader() definition code for java.lang.ClassLoader.getSystemClassLoader() as the parent class loader.

If there is a security manager, its checkCreateClassLoader sample code for java.lang.SecurityManager.checkCreateClassLoader() definition code for java.lang.SecurityManager.checkCreateClassLoader() method is invoked. This may result in a security exception.

Throws:
SecurityException sample code for java.lang.SecurityException definition code for java.lang.SecurityException - If a security manager exists and its checkCreateClassLoader method doesn't allow creation of a new class loader.
Method Detail

loadClass sample code for java.lang.ClassLoader.loadClass(java.lang.String) definition code for java.lang.ClassLoader.loadClass(java.lang.String)

public Class sample code for java.lang.Class definition code for java.lang.Class <?> loadClass(String sample code for java.lang.String definition code for java.lang.String  name)
                   throws ClassNotFoundException sample code for java.lang.ClassNotFoundException definition code for java.lang.ClassNotFoundException 
Loads the class with the specified binary name. This method searches for classes in the same manner as the loadClass(String, boolean) sample code for java.lang.ClassLoader.loadClass(java.lang.String, boolean) definition code for java.lang.ClassLoader.loadClass(java.lang.String, boolean) method. It is invoked by the Java virtual machine to resolve class references. Invoking this method is equivalent to invoking loadClass(name, false) sample code for java.lang.ClassLoader.loadClass(java.lang.String, boolean) definition code for java.lang.ClassLoader.loadClass(java.lang.String, boolean) .

Parameters:
name - The binary name of the class
Returns:
The resulting Class object
Throws:
ClassNotFoundException sample code for java.lang.ClassNotFoundException definition code for java.lang.ClassNotFoundException - If the class was not found

loadClass sample code for java.lang.ClassLoader.loadClass(java.lang.String, boolean) definition code for java.lang.ClassLoader.loadClass(java.lang.String, boolean)

protected Class sample code for java.lang.Class definition code for java.lang.Class <?> loadClass(String sample code for java.lang.String definition code for java.lang.String  name,
                             boolean resolve)
                      throws ClassNotFoundException sample code for java.lang.ClassNotFoundException definition code for java.lang.ClassNotFoundException 
Loads the class with the specified binary name. The default implementation of this method searches for classes in the following order:

  1. Invoke findLoadedClass(String) sample code for java.lang.ClassLoader.findLoadedClass(java.lang.String) definition code for java.lang.ClassLoader.findLoadedClass(java.lang.String) to check if the class has already been loaded.

  2. Invoke the loadClass sample code for java.lang.ClassLoader.loadClass(java.lang.String) definition code for java.lang.ClassLoader.loadClass(java.lang.String) method on the parent class loader. If the parent is null the class loader built-in to the virtual machine is used, instead.

  3. Invoke the findClass(String) sample code for java.lang.ClassLoader.findClass(java.lang.String) definition code for java.lang.ClassLoader.findClass(java.lang.String) method to find the class.

If the class was found using the above steps, and the resolve flag is true, this method will then invoke the resolveClass(Class) sample code for java.lang.ClassLoader.resolveClass(java.lang.Class) definition code for java.lang.ClassLoader.resolveClass(java.lang.Class) method on the resulting Class object.

Subclasses of ClassLoader are encouraged to override findClass(String) sample code for java.lang.ClassLoader.findClass(java.lang.String) definition code for java.lang.ClassLoader.findClass(java.lang.String) , rather than this method.

Parameters:
name - The binary name of the class
resolve - If true then resolve the class
Returns:
The resulting Class object
Throws:
ClassNotFoundException sample code for java.lang.ClassNotFoundException definition code for java.lang.ClassNotFoundException - If the class could not be found

findClass sample code for java.lang.ClassLoader.findClass(java.lang.String) definition code for java.lang.ClassLoader.findClass(java.lang.String)

protected Class sample code for java.lang.Class definition code for java.lang.Class <?> findClass(String sample code for java.lang.String definition code for java.lang.String  name)
                      throws ClassNotFoundException sample code for java.lang.ClassNotFoundException definition code for java.lang.ClassNotFoundException 
Finds the class with the specified binary name. This method should be overridden by class loader implementations that follow the delegation model for loading classes, and will be invoked by the loadClass sample code for java.lang.ClassLoader.loadClass(java.lang.String) definition code for java.lang.ClassLoader.loadClass(java.lang.String) method after checking the parent class loader for the requested class. The default implementation throws a ClassNotFoundException.

Parameters:
name - The binary name of the class
Returns:
The resulting Class object
Throws:
ClassNotFoundException sample code for java.lang.ClassNotFoundException definition code for java.lang.ClassNotFoundException - If the class could not be found
Since:
1.2

defineClass sample code for java.lang.ClassLoader.defineClass(byte[], int, int) definition code for java.lang.ClassLoader.defineClass(byte[], int, int)

@Deprecated
protected final Class sample code for java.lang.Class definition code for java.lang.Class <?> defineClass(byte[] b,
                                                int off,
                                                int len)
                              throws ClassFormatError sample code for java.lang.ClassFormatError definition code for java.lang.ClassFormatError 
Deprecated. Replaced by defineClass(String, byte[], int, int) sample code for java.lang.ClassLoader.defineClass(java.lang.String, byte[], int, int) definition code for java.lang.ClassLoader.defineClass(java.lang.String, byte[], int, int)

Converts an array of bytes into an instance of class Class. Before the Class can be used it must be resolved. This method is deprecated in favor of the version that takes a binary name as its first argument, and is more secure.

Parameters:
b - The bytes that make up the class data. The bytes in positions off through off+len-1 should have the format of a valid class file as defined by the Java Virtual Machine Specification.
off - The start offset in b of the class data
len - The length of the class data
Returns:
The Class object that was created from the specified class data
Throws:
ClassFormatError sample code for java.lang.ClassFormatError definition code for java.lang.ClassFormatError - If the data did not contain a valid class
IndexOutOfBoundsException sample code for java.lang.IndexOutOfBoundsException definition code for java.lang.IndexOutOfBoundsException - If either off or len is negative, or if off+len is greater than b.length.
See Also:
loadClass(String, boolean) sample code for java.lang.ClassLoader.loadClass(java.lang.String, boolean) definition code for java.lang.ClassLoader.loadClass(java.lang.String, boolean) , resolveClass(Class) sample code for java.lang.ClassLoader.resolveClass(java.lang.Class) definition code for java.lang.ClassLoader.resolveClass(java.lang.Class)

defineClass sample code for java.lang.ClassLoader.defineClass(java.lang.String, byte[], int, int) definition code for java.lang.ClassLoader.defineClass(java.lang.String, byte[], int, int)

protected final Class sample code for java.lang.Class definition code for java.lang.Class <?> defineClass(String sample code for java.lang.String definition code for java.lang.String  name,
                                     byte[] b,
                                     int off,
                                     int len)
                              throws ClassFormatError sample code for java.lang.ClassFormatError definition code for java.lang.ClassFormatError 
Converts an array of bytes into an instance of class Class. Before the Class can be used it must be resolved.

This method assigns a default ProtectionDomain sample code for java.security.ProtectionDomain definition code for java.security.ProtectionDomain to the newly defined class. The ProtectionDomain is effectively granted the same set of permissions returned when Policy.getPolicy().getPermissions(new CodeSource(null, null)) sample code for java.security.Policy.getPermissions(java.security.CodeSource) definition code for java.security.Policy.getPermissions(java.security.CodeSource) is invoked. The default domain is created on the first invocation of defineClass sample code for java.lang.ClassLoader.defineClass(java.lang.String, byte[], int, int) definition code for java.lang.ClassLoader.defineClass(java.lang.String, byte[], int, int) , and re-used on subsequent invocations.

To assign a specific ProtectionDomain to the class, use the defineClass sample code for java.lang.ClassLoader.defineClass(java.lang.String, byte[], int, int, java.security.ProtectionDomain) definition code for java.lang.ClassLoader.defineClass(java.lang.String, byte[], int, int, java.security.ProtectionDomain) method that takes a ProtectionDomain as one of its arguments.

Parameters:
name - The expected binary name of the class, or null if not known
b - The bytes that make up the class data. The bytes in positions off through off+len-1 should have the format of a valid class file as defined by the Java Virtual Machine Specification.
off - The start offset in b of the class data
len - The length of the class data
Returns:
The Class object that was created from the specified class data.
Throws:
ClassFormatError sample code for java.lang.ClassFormatError definition code for java.lang.ClassFormatError - If the data did not contain a valid class
IndexOutOfBoundsException sample code for java.lang.IndexOutOfBoundsException definition code for java.lang.IndexOutOfBoundsException - If either off or len is negative, or if off+len is greater than b.length.
SecurityException sample code for java.lang.SecurityException definition code for java.lang.SecurityException - If an attempt is made to add this class to a package that contains classes that were signed by a different set of certificates than this class (which is unsigned), or if name begins with "java.".
Since:
1.1
See Also:
loadClass(String, boolean) sample code for java.lang.ClassLoader.loadClass(java.lang.String, boolean) definition code for java.lang.ClassLoader.loadClass(java.lang.String, boolean) , resolveClass(Class) sample code for java.lang.ClassLoader.resolveClass(java.lang.Class) definition code for java.lang.ClassLoader.resolveClass(java.lang.Class) , CodeSource sample code for java.security.CodeSource definition code for java.security.CodeSource , SecureClassLoader sample code for java.security.SecureClassLoader definition code for java.security.SecureClassLoader

defineClass sample code for java.lang.ClassLoader.defineClass(java.lang.String, byte[], int, int, java.security.ProtectionDomain) definition code for java.lang.ClassLoader.defineClass(java.lang.String, byte[], int, int, java.security.ProtectionDomain)

protected final Class sample code for java.lang.Class definition code for java.lang.Class <?> defineClass(String sample code for java.lang.String definition code for java.lang.String  name,
                                     byte[] b,
                                     int off,
                                     int len,
                                     ProtectionDomain sample code for java.security.ProtectionDomain definition code for java.security.ProtectionDomain  protectionDomain)
                              throws ClassFormatError sample code for java.lang.ClassFormatError definition code for java.lang.ClassFormatError 
Converts an array of bytes into an instance of class Class, with an optional ProtectionDomain. If the domain is null, then a default domain will be assigned to the class as specified in the documentation for defineClass(String, byte[], int, int) sample code for java.lang.ClassLoader.defineClass(java.lang.String, byte[], int, int) definition code for java.lang.ClassLoader.defineClass(java.lang.String, byte[], int, int) . Before the class can be used it must be resolved.

The first class defined in a package determines the exact set of certificates that all subsequent classes defined in that package must contain. The set of certificates for a class is obtained from the CodeSource sample code for java.security.CodeSource definition code for java.security.CodeSource within the ProtectionDomain of the class. Any classes added to that package must contain the same set of certificates or a SecurityException will be thrown. Note that if name is null, this check is not performed. You should always pass in the binary name of the class you are defining as well as the bytes. This ensures that the class you are defining is indeed the class you think it is.

The specified name cannot begin with "java.", since all classes in the "java.* packages can only be defined by the bootstrap class loader. If name is not null, it must be equal to the binary name of the class specified by the byte array "b", otherwise a NoClassDefFoundError will be thrown.

Parameters:
name - The expected binary name of the class, or null if not known
b - The bytes that make up the class data. The bytes in positions off through off+len-1 should have the format of a valid class file as defined by the Java Virtual Machine Specification.
off - The start offset in b of the class data
len - The length of the class data
protectionDomain - The ProtectionDomain of the class
Returns:
The Class object created from the data, and optional ProtectionDomain.
Throws:
ClassFormatError sample code for java.lang.ClassFormatError definition code for java.lang.ClassFormatError - If the data did not contain a valid class
NoClassDefFoundError sample code for java.lang.NoClassDefFoundError definition code for java.lang.NoClassDefFoundError - If name is not equal to the binary name of the class specified by b
IndexOutOfBoundsException sample code for java.lang.IndexOutOfBoundsException definition code for java.lang.IndexOutOfBoundsException - If either off or len is negative, or if off+len is greater than b.length.
SecurityException sample code for java.lang.SecurityException definition code for java.lang.SecurityException - If an attempt is made to add this class to a package that contains classes that were signed by a different set of certificates than this class, or if name begins with "java.".

defineClass sample code for java.lang.ClassLoader.defineClass(java.lang.String, java.nio.ByteBuffer, java.security.ProtectionDomain) definition code for java.lang.ClassLoader.defineClass(java.lang.String, java.nio.ByteBuffer, java.security.ProtectionDomain)

protected final Class sample code for java.lang.Class definition code for java.lang.Class <?> defineClass(String sample code for java.lang.String definition code for java.lang.String  name,
                                     ByteBuffer sample code for java.nio.ByteBuffer definition code for java.nio.ByteBuffer  b,
                                     ProtectionDomain sample code for java.security.ProtectionDomain definition code for java.security.ProtectionDomain  protectionDomain)
                              throws ClassFormatError sample code for java.lang.ClassFormatError definition code for java.lang.ClassFormatError 
Converts a ByteBuffer sample code for java.nio.ByteBuffer definition code for java.nio.ByteBuffer into an instance of class Class, with an optional ProtectionDomain. If the domain is null, then a default domain will be assigned to the class as specified in the documentation for defineClass(String, byte[], int, int) sample code for java.lang.ClassLoader.defineClass(java.lang.String, byte[], int, int) definition code for java.lang.ClassLoader.defineClass(java.lang.String, byte[], int, int) . Before the class can be used it must be resolved.

The rules about the first class defined in a package determining the set of certificates for the package, and the restrictions on class names are identical to those specified in the documentation for defineClass(String, byte[], int, int, ProtectionDomain) sample code for java.lang.ClassLoader.defineClass(java.lang.String, byte[], int, int, java.security.ProtectionDomain) definition code for java.lang.ClassLoader.defineClass(java.lang.String, byte[], int, int, java.security.ProtectionDomain) .

An invocation of this method of the form cl.defineClass(name, bBuffer, pd) yields exactly the same result as the statements

...
byte[] temp = new byte[
bBuffer.remaining sample code for java.nio.Buffer.remaining() definition code for java.nio.Buffer.remaining() ()];
bBuffer.get sample code for java.nio.ByteBuffer.get(byte[]) definition code for java.nio.ByteBuffer.get(byte[]) (temp);
return
cl.defineClass sample code for java.lang.ClassLoader.defineClass(java.lang.String, byte[], int, int, java.security.ProtectionDomain) definition code for java.lang.ClassLoader.defineClass(java.lang.String, byte[], int, int, java.security.ProtectionDomain) (name, temp, 0, temp.length, pd);

Parameters:
name - The expected binary namenull if not known
b - The bytes that make up the class data. The bytes from positions b.position() through b.position() + b.limit() -1 should have the format of a valid class file as defined by the Java Virtual Machine Specification.
protectionDomain - The ProtectionDomain of the class, or null.
Returns:
The Class object created from the data, and optional ProtectionDomain.
Throws:
ClassFormatError sample code for java.lang.ClassFormatError definition code for java.lang.ClassFormatError - If the data did not contain a valid class.
NoClassDefFoundError sample code for java.lang.NoClassDefFoundError definition code for java.lang.NoClassDefFoundError - If name is not equal to the binary name of the class specified by b
SecurityException sample code for java.lang.SecurityException definition code for java.lang.SecurityException - If an attempt is made to add this class to a package that contains classes that were signed by a different set of certificates than this class, or if name begins with "java.".
Since:
1.5
See Also:
defineClass(String, byte[], int, int, ProtectionDomain) sample code for java.lang.ClassLoader.defineClass(java.lang.String, byte[], int, int, java.security.ProtectionDomain) definition code for java.lang.ClassLoader.defineClass(java.lang.String, byte[], int, int, java.security.ProtectionDomain)

resolveClass sample code for java.lang.ClassLoader.resolveClass(java.lang.Class<?>) definition code for java.lang.ClassLoader.resolveClass(java.lang.Class<?>)

protected final void resolveClass(Class sample code for java.lang.Class definition code for java.lang.Class <?> c)
Links the specified class. This (misleadingly named) method may be used by a class loader to link a class. If the class c has already been linked, then this method simply returns. Otherwise, the class is linked as described in the "Execution" chapter of the Java Language Specification.

Parameters:
c - The class to link
Throws:
NullPointerException sample code for java.lang.NullPointerException definition code for java.lang.NullPointerException - If c is null.
See Also:
defineClass(String, byte[], int, int) sample code for java.lang.ClassLoader.defineClass(java.lang.String, byte[], int, int) definition code for java.lang.ClassLoader.defineClass(java.lang.String, byte[], int, int)

findSystemClass sample code for java.lang.ClassLoader.findSystemClass(java.lang.String) definition code for java.lang.ClassLoader.findSystemClass(java.lang.String)

protected final Class sample code for java.lang.Class definition code for java.lang.Class <?> findSystemClass(String sample code for java.lang.String definition code for java.lang.String  name)
                                  throws ClassNotFoundException sample code for java.lang.ClassNotFoundException definition code for java.lang.ClassNotFoundException 
Finds a class with the specified binary name, loading it if necessary.

This method loads the class through the system class loader (see getSystemClassLoader() sample code for java.lang.ClassLoader.getSystemClassLoader() definition code for java.lang.ClassLoader.getSystemClassLoader() ). The Class object returned might have more than one ClassLoader associated with it. Subclasses of ClassLoader need not usually invoke this method, because most class loaders need to override just findClass(String) sample code for java.lang.ClassLoader.findClass(java.lang.String) definition code for java.lang.ClassLoader.findClass(java.lang.String) .

Parameters:
name - The binary name of the class
Returns:
The Class object for the specified name
Throws:
ClassNotFoundException sample code for java.lang.ClassNotFoundException definition code for java.lang.ClassNotFoundException - If the class could not be found
See Also:
ClassLoader(ClassLoader) sample code for java.lang.ClassLoader.ClassLoader(java.lang.ClassLoader) definition code for java.lang.ClassLoader.ClassLoader(java.lang.ClassLoader) , getParent() sample code for java.lang.ClassLoader.getParent() definition code for java.lang.ClassLoader.getParent()

findLoadedClass sample code for java.lang.ClassLoader.findLoadedClass(java.lang.String) definition code for java.lang.ClassLoader.findLoadedClass(java.lang.String)

protected final Class sample code for java.lang.Class definition code for java.lang.Class <?> findLoadedClass(String sample code for java.lang.String definition code for java.lang.String  name)
Returns the class with the given binary name if this loader has been recorded by the Java virtual machine as an initiating loader of a class with that binary name. Otherwise null is returned.

Parameters:
name - The binary name of the class
Returns:
The Class object, or null if the class has not been loaded
Since:
1.1

setSigners sample code for java.lang.ClassLoader.setSigners(java.lang.Class<?>, java.lang.Object[]) definition code for java.lang.ClassLoader.setSigners(java.lang.Class<?>, java.lang.Object[])

protected final void setSigners(Class sample code for java.lang.Class definition code for java.lang.Class <?> c,
                                Object sample code for java.lang.Object definition code for java.lang.Object [] signers)
Sets the signers of a class. This should be invoked after defining a class.

Parameters:
c - The Class object
signers - The signers for the class
Since:
1.1

getResource sample code for java.lang.ClassLoader.getResource(java.lang.String) definition code for java.lang.ClassLoader.getResource(java.lang.String)

public URL sample code for java.net.URL definition code for java.net.URL  getResource(String sample code for java.lang.String definition code for java.lang.String  name)
Finds the resource with the given name. A resource is some data (images, audio, text, etc) that can be accessed by class code in a way that is independent of the location of the code.

The name of a resource is a '/'-separated path name that identifies the resource.

This method will first search the parent class loader for the resource; if the parent is null the path of the class loader built-in to the virtual machine is searched. That failing, this method will invoke findResource(String) sample code for java.lang.ClassLoader.findResource(java.lang.String) definition code for java.lang.ClassLoader.findResource(java.lang.String) to find the resource.

Parameters:
name - The resource name
Returns:
A URL object for reading the resource, or null if the resource could not be found or the invoker doesn't have adequate privileges to get the resource.
Since:
1.1

getResources sample code for java.lang.ClassLoader.getResources(java.lang.String) definition code for java.lang.ClassLoader.getResources(java.lang.String)

public Enumeration sample code for java.util.Enumeration definition code for java.util.Enumeration <URL sample code for java.net.URL definition code for java.net.URL > getResources(String sample code for java.lang.String definition code for java.lang.String  name)
                              throws IOException sample code for java.io.IOException definition code for java.io.IOException 
Finds all the resources with the given name. A resource is some data (images, audio, text, etc) that can be accessed by class code in a way that is independent of the location of the code.

The name of a resource is a /-separated path name that identifies the resource.

The search order is described in the documentation for getResource(String) sample code for java.lang.ClassLoader.getResource(java.lang.String) definition code for java.lang.ClassLoader.getResource(java.lang.String) .

Parameters:
name - The resource name
Returns:
An enumeration of URL sample code for java.net.URL definition code for java.net.URL objects for the resource. If no resources could be found, the enumeration will be empty. Resources that the class loader doesn't have access to will not be in the enumeration.
Throws:
IOException sample code for java.io.IOException definition code for java.io.IOException - If I/O errors occur
Since:
1.2
See Also:
findResources(String) sample code for java.lang.ClassLoader.findResources(java.lang.String) definition code for java.lang.ClassLoader.findResources(java.lang.String)

findResource sample code for java.lang.ClassLoader.findResource(java.lang.String) definition code for java.lang.ClassLoader.findResource(java.lang.String)

protected URL sample code for java.net.URL definition code for java.net.URL  findResource(String sample code for java.lang.String definition code for java.lang.String  name)
Finds the resource with the given name. Class loader implementations should override this method to specify where to find resources.

Parameters:
name - The resource name
Returns:
A URL object for reading the resource, or null if the resource could not be found
Since:
1.2

findResources sample code for java.lang.ClassLoader.findResources(java.lang.String) definition code for java.lang.ClassLoader.findResources(java.lang.String)

protected Enumeration sample code for java.util.Enumeration definition code for java.util.Enumeration <URL sample code for java.net.URL definition code for java.net.URL > findResources(String sample code for java.lang.String definition code for java.lang.String  name)
                                  throws IOException sample code for java.io.IOException definition code for java.io.IOException 
Returns an enumeration of URL sample code for java.net.URL definition code for java.net.URL objects representing all the resources with the given name. Class loader implementations should override this method to specify where to load resources from.

Parameters:
name - The resource name
Returns:
An enumeration of URL sample code for java.net.URL definition code for java.net.URL objects for the resources
Throws:
IOException sample code for java.io.IOException definition code for java.io.IOException - If I/O errors occur
Since:
1.2

getSystemResource sample code for java.lang.ClassLoader.getSystemResource(java.lang.String) definition code for java.lang.ClassLoader.getSystemResource(java.lang.String)

public static URL sample code for java.net.URL definition code for java.net.URL  getSystemResource(String sample code for java.lang.String definition code for java.lang.String  name)
Find a resource of the specified name from the search path used to load classes. This method locates the resource through the system class loader (see getSystemClassLoader() sample code for java.lang.ClassLoader.getSystemClassLoader() definition code for java.lang.ClassLoader.getSystemClassLoader() ).

Parameters:
name - The resource name
Returns:
A URL sample code for java.net.URL definition code for java.net.URL object for reading the resource, or null if the resource could not be found
Since:
1.1

getSystemResources sample code for java.lang.ClassLoader.getSystemResources(java.lang.String) definition code for java.lang.ClassLoader.getSystemResources(java.lang.String)

public static Enumeration sample code for java.util.Enumeration definition code for java.util.Enumeration <URL sample code for java.net.URL definition code for java.net.URL > getSystemResources(String sample code for java.lang.String definition code for java.lang.String  name)
                                           throws IOException sample code for java.io.IOException definition code for java.io.IOException 
Finds all resources of the specified name from the search path used to load classes. The resources thus found are returned as an Enumeration sample code for java.util.Enumeration definition code for java.util.Enumeration of URL sample code for java.net.URL definition code for java.net.URL objects.

The search order is described in the documentation for getSystemResource(String) sample code for java.lang.ClassLoader.getSystemResource(java.lang.String) definition code for java.lang.ClassLoader.getSystemResource(java.lang.String) .

Parameters:
name - The resource name
Returns:
An enumeration of resource URL sample code for java.net.URL definition code for java.net.URL objects
Throws:
IOException sample code for java.io.IOException definition code for java.io.IOException - If I/O errors occur
Since:
1.2

getResourceAsStream sample code for java.lang.ClassLoader.getResourceAsStream(java.lang.String) definition code for java.lang.ClassLoader.getResourceAsStream(java.lang.String)

public InputStream sample code for java.io.InputStream definition code for java.io.InputStream  getResourceAsStream(String sample code for java.lang.String definition code for java.lang.String  name)
Returns an input stream for reading the specified resource.

The search order is described in the documentation for getResource(String) sample code for java.lang.ClassLoader.getResource(java.lang.String) definition code for java.lang.ClassLoader.getResource(java.lang.String) .

Parameters:
name - The resource name
Returns:
An input stream for reading the resource, or null if the resource could not be found
Since:
1.1

getSystemResourceAsStream sample code for java.lang.ClassLoader.getSystemResourceAsStream(java.lang.String) definition code for java.lang.ClassLoader.getSystemResourceAsStream(java.lang.String)

public static InputStream sample code for java.io.InputStream definition code for java.io.InputStream  getSystemResourceAsStream(String sample code for java.lang.String definition code for java.lang.String  name)
Open for reading, a resource of the specified name from the search path used to load classes. This method locates the resource through the system class loader (see getSystemClassLoader() sample code for java.lang.ClassLoader.getSystemClassLoader() definition code for java.lang.ClassLoader.getSystemClassLoader() ).

Parameters:
name - The resource name
Returns:
An input stream for reading the resource, or null if the resource could not be found
Since:
1.1

getParent sample code for java.lang.ClassLoader.getParent() definition code for java.lang.ClassLoader.getParent()

public final ClassLoader sample code for java.lang.ClassLoader definition code for java.lang.ClassLoader  getParent()
Returns the parent class loader for delegation. Some implementations may use null to represent the bootstrap class loader. This method will return null in such implementations if this class loader's parent is the bootstrap class loader.

If a security manager is present, and the invoker's class loader is not null and is not an ancestor of this class loader, then this method invokes the security manager's checkPermission sample code for java.lang.SecurityManager.checkPermission(java.security.Permission) definition code for java.lang.SecurityManager.checkPermission(java.security.Permission) method with a RuntimePermission("getClassLoader") sample code for java.lang.RuntimePermission.RuntimePermission(java.lang.String) definition code for java.lang.RuntimePermission.RuntimePermission(java.lang.String) permission to verify access to the parent class loader is permitted. If not, a SecurityException will be thrown.

Returns:
The parent ClassLoader
Throws:
SecurityException sample code for java.lang.SecurityException definition code for java.lang.SecurityException - If a security manager exists and its checkPermission method doesn't allow access to this class loader's parent class loader.
Since:
1.2

getSystemClassLoader sample code for java.lang.ClassLoader.getSystemClassLoader() definition code for java.lang.ClassLoader.getSystemClassLoader()

public static ClassLoader sample code for java.lang.ClassLoader definition code for java.lang.ClassLoader  getSystemClassLoader()
Returns the system class loader for delegation. This is the default delegation parent for new ClassLoader instances, and is typically the class loader used to start the application.

This method is first invoked early in the runtime's startup sequence, at which point it creates the system class loader and sets it as the context class loader of the invoking Thread.

The default system class loader is an implementation-dependent instance of this class.

If the system property "java.system.class.loader" is defined when this method is first invoked then the value of that property is taken to be the name of a class that will be returned as the system class loader. The class is loaded using the default system class loader and must define a public constructor that takes a single parameter of type ClassLoader which is used as the delegation parent. An instance is then created using this constructor with the default system class loader as the parameter. The resulting class loader is defined to be the system class loader.

If a security manager is present, and the invoker's class loader is not null and the invoker's class loader is not the same as or an ancestor of the system class loader, then this method invokes the security manager's checkPermission sample code for java.lang.SecurityManager.checkPermission(java.security.Permission) definition code for java.lang.SecurityManager.checkPermission(java.security.Permission) method with a RuntimePermission("getClassLoader") sample code for java.lang.RuntimePermission.RuntimePermission(java.lang.String) definition code for java.lang.RuntimePermission.RuntimePermission(java.lang.String) permission to verify access to the system class loader. If not, a SecurityException will be thrown.

Returns:
The system ClassLoader for delegation, or null if none
Throws:
SecurityException sample code for java.lang.SecurityException definition code for java.lang.SecurityException - If a security manager exists and its checkPermission method doesn't allow access to the system class loader.
IllegalStateException sample code for java.lang.IllegalStateException definition code for java.lang.IllegalStateException - If invoked recursively during the construction of the class loader specified by the "java.system.class.loader" property.
Error sample code for java.lang.Error definition code for java.lang.Error - If the system property "java.system.class.loader" is defined but the named class could not be loaded, the provider class does not define the required constructor, or an exception is thrown by that constructor when it is invoked. The underlying cause of the error can be retrieved via the Throwable.getCause() sample code for java.lang.Throwable.getCause() definition code for java.lang.Throwable.getCause() method.

definePackage sample code for java.lang.ClassLoader.definePackage(java.lang.String, java.lang.String, java.lang.String, java.lang.String, java.lang.String, java.lang.String, java.lang.String, java.net.URL) definition code for java.lang.ClassLoader.definePackage(java.lang.String, java.lang.String, java.lang.String, java.lang.String, java.lang.String, java.lang.String, java.lang.String, java.net.URL)

protected Package sample code for java.lang.Package definition code for java.lang.Package  definePackage(String sample code for java.lang.String definition code for java.lang.String  name,
                                String sample code for java.lang.String definition code for java.lang.String  specTitle,
                                String sample code for java.lang.String definition code for java.lang.String  specVersion,
                                String sample code for java.lang.String definition code for java.lang.String  specVendor,
                                String sample code for java.lang.String definition code for java.lang.String  implTitle,
                                String sample code for java.lang.String definition code for java.lang.String  implVersion,
                                String sample code for java.lang.String definition code for java.lang.String  implVendor,
                                URL sample code for java.net.URL definition code for java.net.URL  sealBase)
                         throws IllegalArgumentException sample code for java.lang.IllegalArgumentException definition code for java.lang.IllegalArgumentException 
Defines a package by name in this ClassLoader. This allows class loaders to define the packages for their classes. Packages must be created before the class is defined, and package names must be unique within a class loader and cannot be redefined or changed once created.

Parameters:
name - The package name
specTitle - The specification title
specVersion - The specification version
specVendor - The specification vendor
implTitle - The implementation title
implVersion - The implementation version
implVendor - The implementation vendor
sealBase - If not null, then this package is sealed with respect to the given code source URL sample code for java.net.URL definition code for java.net.URL object. Otherwise, the package is not sealed.
Returns:
The newly defined Package object
Throws:
IllegalArgumentException sample code for java.lang.IllegalArgumentException definition code for java.lang.IllegalArgumentException - If package name duplicates an existing package either in this class loader or one of its ancestors
Since:
1.2

getPackage sample code for java.lang.ClassLoader.getPackage(java.lang.String) definition code for java.lang.ClassLoader.getPackage(java.lang.String)

protected Package sample code for java.lang.Package definition code for java.lang.Package  getPackage(String sample code for java.lang.String definition code for java.lang.String  name)
Returns a Package that has been defined by this class loader or any of its ancestors.

Parameters:
name - The package name
Returns:
The Package corresponding to the given name, or null if not found
Since:
1.2

getPackages sample code for java.lang.ClassLoader.getPackages() definition code for java.lang.ClassLoader.getPackages()

protected Package sample code for java.lang.Package definition code for java.lang.Package [] getPackages()
Returns all of the Packages defined by this class loader and its ancestors.

Returns:
The array of Package objects defined by this ClassLoader
Since:
1.2

findLibrary sample code for java.lang.ClassLoader.findLibrary(java.lang.String) definition code for java.lang.ClassLoader.findLibrary(java.lang.String)

protected String sample code for java.lang.String definition code for java.lang.String  findLibrary(String sample code for java.lang.String definition code for java.lang.String  libname)
Returns the absolute path name of a native library. The VM invokes this method to locate the native libraries that belong to classes loaded with this class loader. If this method returns null, the VM searches the library along the path specified as the "java.library.path" property.

Parameters:
libname - The library name
Returns:
The absolute path of the native library
Since:
1.2
See Also:
System.loadLibrary(String) sample code for java.lang.System.loadLibrary(java.lang.String) definition code for java.lang.System.loadLibrary(java.lang.String) , System.mapLibraryName(String) sample code for java.lang.System.mapLibraryName(java.lang.String) definition code for java.lang.System.mapLibraryName(java.lang.String)

setDefaultAssertionStatus sample code for java.lang.ClassLoader.setDefaultAssertionStatus(boolean) definition code for java.lang.ClassLoader.setDefaultAssertionStatus(boolean)

public void setDefaultAssertionStatus(boolean enabled)
Sets the default assertion status for this class loader. This setting determines whether classes loaded by this class loader and initialized in the future will have assertions enabled or disabled by default. This setting may be overridden on a per-package or per-class basis by invoking setPackageAssertionStatus(String, boolean) sample code for java.lang.ClassLoader.setPackageAssertionStatus(java.lang.String, boolean) definition code for java.lang.ClassLoader.setPackageAssertionStatus(java.lang.String, boolean) or setClassAssertionStatus(String, boolean) sample code for java.lang.ClassLoader.setClassAssertionStatus(java.lang.String, boolean) definition code for java.lang.ClassLoader.setClassAssertionStatus(java.lang.String, boolean) .

Parameters:
enabled - true if classes loaded by this class loader will henceforth have assertions enabled by default, false if they will have assertions disabled by default.
Since:
1.4

setPackageAssertionStatus sample code for java.lang.ClassLoader.setPackageAssertionStatus(java.lang.String, boolean) definition code for java.lang.ClassLoader.setPackageAssertionStatus(java.lang.String, boolean)

public void setPackageAssertionStatus(String sample code for java.lang.String definition code for java.lang.String  packageName,
                                      boolean enabled)
Sets the package default assertion status for the named package. The package default assertion status determines the assertion status for classes initialized in the future that belong to the named package or any of its "subpackages".

A subpackage of a package named p is any package whose name begins with "p.". For example, javax.swing.text is a subpackage of javax.swing, and both java.util and java.lang.reflect are subpackages of java.

In the event that multiple package defaults apply to a given class, the package default pertaining to the most specific package takes precedence over the others. For example, if javax.lang and javax.lang.reflect both have package defaults associated with them, the latter package default applies to classes in javax.lang.reflect.

Package defaults take precedence over the class loader's default assertion status, and may be overridden on a per-class basis by invoking setClassAssertionStatus(String, boolean) sample code for java.lang.ClassLoader.setClassAssertionStatus(java.lang.String, boolean) definition code for java.lang.ClassLoader.setClassAssertionStatus(java.lang.String, boolean) .

Parameters:
packageName - The name of the package whose package default assertion status is to be set. A null value indicates the unnamed package that is "current" (Java Language Specification, section 7.4.2).
enabled - true if classes loaded by this classloader and belonging to the named package or any of its subpackages will have assertions enabled by default, false if they will have assertions disabled by default.
Since:
1.4

setClassAssertionStatus sample code for java.lang.ClassLoader.setClassAssertionStatus(java.lang.String, boolean) definition code for java.lang.ClassLoader.setClassAssertionStatus(java.lang.String, boolean)

public void setClassAssertionStatus(String sample code for java.lang.String definition code for java.lang.String  className,
                                    boolean enabled)
Sets the desired assertion status for the named top-level class in this class loader and any nested classes contained therein. This setting takes precedence over the class loader's default assertion status, and over any applicable per-package default. This method has no effect if the named class has already been initialized. (Once a class is initialized, its assertion status cannot change.)

If the named class is not a top-level class, this invocation will have no effect on the actual assertion status of any class, and its return value is undefined.

Parameters:
className - The fully qualified class name of the top-level class whose assertion status is to be set.
enabled - true if the named class is to have assertions enabled when (and if) it is initialized, false if the class is to have assertions disabled.
Since:
1.4

clearAssertionStatus sample code for java.lang.ClassLoader.clearAssertionStatus() definition code for java.lang.ClassLoader.clearAssertionStatus()

public void clearAssertionStatus()
Sets the default assertion status for this class loader to false and discards any package defaults or class assertion status settings associated with the class loader. This method is provided so that class loaders can be made to ignore any command line or persistent assertion status settings and "start with a clean slate."

Since:
1.4