org.apache.avalon.fortress.impl.factory

Class BCELWrapperGenerator

java.lang.Object

org.apache.avalon.fortress.impl.factory.BCELWrapperGenerator

final class BCELWrapperGenerator
extends java.lang.Object

Create the BCELWrapper for the component. The generated wrapper classes will be assigned the same ProtectionDomain as the actual classes which they are wrapping. This simplifies the configuration of a SecurityManager by making the existence of the BCEL generated classes transparent to the policy file author.

Author:

Avalon Development Team

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
private class	BCELWrapperGenerator.BCELClassLoader

Field Summary

Fields

Modifier and Type	Field and Description
private BCELWrapperGenerator.BCELClassLoader	m_bcelClassLoader The ClassLoader to use when loading a class generated by this BCELWrapperGenerator.
private org.apache.bcel.generic.ClassGen	m_classGenerator The ClassGen instance to use for byte code generation.
private BCELCodeGenerator	m_codeGenerator The BCELCodeGenerator to use for byte code generation.
private org.apache.bcel.util.Repository	m_repository The BCEL util.Repository instance to use when loading JavaClass instances.
private static java.lang.String	WRAPPER_CLASS_INTERFACE_NAME The name of the interface each generated wrapper class has to implement.
private static java.lang.String	WRAPPER_CLASS_SUFFIX The suffix to be appended to the name of the wrapped class when creating the name of the wrapper class.
private static java.lang.String	WRAPPER_SUPERCLASS_NAME The name of the superclass of the wrapper class to be generated.

Constructor Summary

Constructors

Constructor and Description
BCELWrapperGenerator() No-args default constructor.

Method Summary

Methods

Modifier and Type	Method and Description
private byte[]	buildWrapper(org.apache.bcel.classfile.JavaClass[] interfacesToImplement) Generates the wrapper byte code for a given interface.
java.lang.Class	createWrapper(java.lang.Class classToWrap)
private java.lang.String[]	extractInterfaceNames(java.lang.Class[] interfaces) Takes an array of Class instances supposed to represent interfaces and returns a list of the names of those interfaces.
private org.apache.bcel.classfile.JavaClass	lookupClass(java.lang.Class clazz) Takes a Class instance as a its parameter and returns corresponding the JavaClass instance as used by BCEL.
private org.apache.bcel.classfile.JavaClass[]	lookupClasses(java.lang.Class[] classes) Takes an array of Class instances and returns an array holding the corresponding JavaClass instances as used by BCEL.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

m_repository

private org.apache.bcel.util.Repository m_repository

The BCEL util.Repository instance to use when loading JavaClass instances. Default is to use util.ClassLoaderRepository with thread context classloader.

WRAPPER_CLASS_SUFFIX

private static final java.lang.String WRAPPER_CLASS_SUFFIX

The suffix to be appended to the name of the wrapped class when creating the name of the wrapper class.

See Also:

Constant Field Values

WRAPPER_SUPERCLASS_NAME

private static final java.lang.String WRAPPER_SUPERCLASS_NAME

The name of the superclass of the wrapper class to be generated.

See Also:

Constant Field Values

WRAPPER_CLASS_INTERFACE_NAME

private static final java.lang.String WRAPPER_CLASS_INTERFACE_NAME

The name of the interface each generated wrapper class has to implement.

m_codeGenerator

private final BCELCodeGenerator m_codeGenerator

The BCELCodeGenerator to use for byte code generation.

m_classGenerator

private org.apache.bcel.generic.ClassGen m_classGenerator

The ClassGen instance to use for byte code generation.

m_bcelClassLoader

private final BCELWrapperGenerator.BCELClassLoader m_bcelClassLoader

The ClassLoader to use when loading a class generated by this BCELWrapperGenerator.

Constructor Detail

BCELWrapperGenerator

public BCELWrapperGenerator()

No-args default constructor.

Method Detail

createWrapper

public java.lang.Class createWrapper(java.lang.Class classToWrap)
                              throws java.lang.Exception

Throws:

java.lang.Exception

lookupClass

private org.apache.bcel.classfile.JavaClass lookupClass(java.lang.Class clazz)
                                                 throws java.lang.Exception

Takes a Class instance as a its parameter and returns corresponding the JavaClass instance as used by BCEL.

Parameters:

clazz - The Class instance we want to turn into a JavaClass

Returns:

The JavaClass representing the given Class instance

Throws:

java.lang.Exception

lookupClasses

private org.apache.bcel.classfile.JavaClass[] lookupClasses(java.lang.Class[] classes)
                                                     throws java.lang.Exception

Takes an array of Class instances and returns an array holding the corresponding JavaClass instances as used by BCEL.

Parameters:

classes - An array holding Class instances we want to turn into JavaClass instances

Returns:

JavaClass[] An array of JavaClass instances representing the given Class instances

Throws:

java.lang.Exception

extractInterfaceNames

private java.lang.String[] extractInterfaceNames(java.lang.Class[] interfaces)

Takes an array of Class instances supposed to represent interfaces and returns a list of the names of those interfaces.

Parameters:

interfaces - An array of Class instances

Returns:

String[] An array of the names of those Class instances

buildWrapper

private byte[] buildWrapper(org.apache.bcel.classfile.JavaClass[] interfacesToImplement)
                     throws java.lang.Exception

Generates the wrapper byte code for a given interface.

Parameters:

interfacesToImplement - The interfaces we want to generate wrapper byte code for

Returns:

byte[] The generated byte code

Throws:

java.lang.Exception