Class SecureClassLoader
- java.lang.Object
-
- java.lang.ClassLoader
-
- java.security.SecureClassLoader
- Direct Known Subclasses:
URLClassLoader
public class SecureClassLoader extends ClassLoader
This class extends ClassLoader with additional support for defining classes with an associated code source and permissions which are retrieved by the system policy by default.
- Since:
- 1.2
Constructor Summary
Modifier | Constructor | Description |
---|---|---|
protected | SecureClassLoader() | Creates a new SecureClassLoader using the default parent class loader for delegation. |
protected | SecureClassLoader(ClassLoader parent) | Creates a new SecureClassLoader using the specified parent class loader for delegation. |
protected | SecureClassLoader(String name,
ClassLoader parent) | Creates a new |
Method Summary
Modifier and Type | Method | Description |
---|---|---|
protected Class<?> | defineClass(String name,
byte[] b,
int off,
int len,
CodeSource cs) | Converts an array of bytes into an instance of class Class, with an optional CodeSource. |
protected Class<?> | defineClass(String name,
ByteBuffer b,
CodeSource cs) | Converts a |
protected PermissionCollection | getPermissions(CodeSource codesource) | Returns the permissions for the given CodeSource object. |
Methods declared in class java.lang.ClassLoader
clearAssertionStatus, defineClass, defineClass, defineClass, defineClass, definePackage, findClass, findClass, findLibrary, findLoadedClass, findResource, findResource, findResources, findSystemClass, getClassLoadingLock, getDefinedPackage, getDefinedPackages, getName, getPackage, getPackages, getParent, getPlatformClassLoader, getResource, getResourceAsStream, getResources, getSystemClassLoader, getSystemResource, getSystemResourceAsStream, getSystemResources, getUnnamedModule, isRegisteredAsParallelCapable, loadClass, loadClass, registerAsParallelCapable, resolveClass, resources, setClassAssertionStatus, setDefaultAssertionStatus, setPackageAssertionStatus, setSigners
Methods declared in class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
Constructor Detail
SecureClassLoader
protected SecureClassLoader(ClassLoader parent)
Creates a new SecureClassLoader using the specified parent class loader for delegation.
If there is a security manager, this method first calls the security manager's checkCreateClassLoader
method to ensure creation of a class loader is allowed.
- Parameters:
-
parent
- the parent ClassLoader - Throws:
-
SecurityException
- if a security manager exists and itscheckCreateClassLoader
method doesn't allow creation of a class loader. - See Also:
SecurityManager.checkCreateClassLoader()
SecureClassLoader
protected SecureClassLoader()
Creates a new SecureClassLoader using the default parent class loader for delegation.
If there is a security manager, this method first calls the security manager's checkCreateClassLoader
method to ensure creation of a class loader is allowed.
- Throws:
-
SecurityException
- if a security manager exists and itscheckCreateClassLoader
method doesn't allow creation of a class loader. - See Also:
SecurityManager.checkCreateClassLoader()
SecureClassLoader
protected SecureClassLoader(String name, ClassLoader parent)
Creates a new SecureClassLoader
of the specified name and using the specified parent class loader for delegation.
- Parameters:
-
name
- class loader name; ornull
if not named -
parent
- the parent class loader - Throws:
-
IllegalArgumentException
- if the given name is empty. -
SecurityException
- if a security manager exists and itsSecurityManager.checkCreateClassLoader()
method doesn't allow creation of a class loader. - Since:
- 9
Method Detail
defineClass
protected final Class<?> defineClass(String name, byte[] b, int off, int len, CodeSource cs)
Converts an array of bytes into an instance of class Class, with an optional CodeSource. Before the class can be used it must be resolved.
If a non-null CodeSource is supplied a ProtectionDomain is constructed and associated with the class being defined.
- Parameters:
-
name
- the expected name of the class, ornull
if not known, using '.' and not '/' as the separator and without a trailing ".class" suffix. -
b
- the bytes that make up the class data. The bytes in positionsoff
throughoff+len-1
should have the format of a valid class file as defined by The Java™ Virtual Machine Specification. -
off
- the start offset inb
of the class data -
len
- the length of the class data -
cs
- the associated CodeSource, ornull
if none - Returns:
- the
Class
object created from the data, and optional CodeSource. - Throws:
-
ClassFormatError
- if the data did not contain a valid class -
IndexOutOfBoundsException
- if eitheroff
orlen
is negative, or ifoff+len
is greater thanb.length
. -
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 the class name begins with "java.".
defineClass
protected final Class<?> defineClass(String name, ByteBuffer b, CodeSource cs)
Converts a ByteBuffer
into an instance of class Class
, with an optional CodeSource. Before the class can be used it must be resolved.
If a non-null CodeSource is supplied a ProtectionDomain is constructed and associated with the class being defined.
- Parameters:
-
name
- the expected name of the class, ornull
if not known, using '.' and not '/' as the separator and without a trailing ".class" suffix. -
b
- the bytes that make up the class data. The bytes from positionsb.position()
throughb.position() + b.limit() -1
should have the format of a valid class file as defined by The Java™ Virtual Machine Specification. -
cs
- the associated CodeSource, ornull
if none - Returns:
- the
Class
object created from the data, and optional CodeSource. - Throws:
-
ClassFormatError
- if the data did not contain a valid class -
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 the class name begins with "java.". - Since:
- 1.5
getPermissions
protected PermissionCollection getPermissions(CodeSource codesource)
Returns the permissions for the given CodeSource object.
This method is invoked by the defineClass method which takes a CodeSource as an argument when it is constructing the ProtectionDomain for the class being defined.
- Parameters:
-
codesource
- the codesource. - Returns:
- the permissions granted to the codesource.