SecureClassLoader
public
class
SecureClassLoader
extends ClassLoader
java.lang.Object | ||
↳ | java.lang.ClassLoader | |
↳ | java.security.SecureClassLoader |
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.
Summary
Protected constructors | |
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SecureClassLoader()
Creates a new SecureClassLoader using the default parent class loader for delegation. |
|
SecureClassLoader(ClassLoader parent)
Creates a new SecureClassLoader using the specified parent class loader for delegation. |
Protected methods | |
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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. |
final
Class<?>
|
defineClass(String name, ByteBuffer b, CodeSource cs)
Converts a |
PermissionCollection
|
getPermissions(CodeSource codesource)
Returns the permissions for the given CodeSource object. |
Inherited methods | |
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Protected constructors
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 its
checkCreateClassLoader method doesn't allow
creation of a class loader. |
See also:
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 | |
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parent |
ClassLoader : the parent ClassLoader |
Throws | |
---|---|
SecurityException |
if a security manager exists and its
checkCreateClassLoader method doesn't allow
creation of a class loader. |
See also:
Protected methods
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 | |
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name |
String : the expected name of the class, or null
if not known, using '.' and not '/' as the separator
and without a trailing ".class" suffix. |
b |
byte : 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 |
int : the start offset in b of the class data |
len |
int : the length of the class data |
cs |
CodeSource : the associated CodeSource, or null if none |
Returns | |
---|---|
Class<?> |
the Class object created from the data,
and optional CodeSource. |
Throws | |
---|---|
ClassFormatError |
if the data did not contain a valid class |
IndexOutOfBoundsException |
if either off or
len is negative, or if
off+len is greater than b.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 | |
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name |
String : the expected name of the class, or null
if not known, using '.' and not '/' as the separator
and without a trailing ".class" suffix. |
b |
ByteBuffer : 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. |
cs |
CodeSource : the associated CodeSource, or null if none |
Returns | |
---|---|
Class<?> |
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.". |
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 | |
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codesource |
CodeSource : the codesource. |
Returns | |
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PermissionCollection |
the permissions granted to the codesource. |