org.objectweb.asm.ClassVisitor Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of asm-util Show documentation
Show all versions of asm-util Show documentation
Utilities for ASM, a very small and fast Java bytecode manipulation framework
/***
* ASM: a very small and fast Java bytecode manipulation framework
* Copyright (c) 2000-2011 INRIA, France Telecom
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the copyright holders nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
* THE POSSIBILITY OF SUCH DAMAGE.
*/
package org.objectweb.asm;
/**
* A visitor to visit a Java class. The methods of this class must be called in
* the following order: visit [ visitSource ] [
* visitOuterClass ] ( visitAnnotation |
* visitTypeAnnotation | visitAttribute )* (
* visitInnerClass | visitField | visitMethod )*
* visitEnd.
*
* @author Eric Bruneton
*/
public abstract class ClassVisitor {
/**
* The ASM API version implemented by this visitor. The value of this field
* must be one of {@link Opcodes#ASM4} or {@link Opcodes#ASM5}.
*/
protected final int api;
/**
* The class visitor to which this visitor must delegate method calls. May
* be null.
*/
protected ClassVisitor cv;
/**
* Constructs a new {@link ClassVisitor}.
*
* @param api
* the ASM API version implemented by this visitor. Must be one
* of {@link Opcodes#ASM4} or {@link Opcodes#ASM5}.
*/
public ClassVisitor(final int api) {
this(api, null);
}
/**
* Constructs a new {@link ClassVisitor}.
*
* @param api
* the ASM API version implemented by this visitor. Must be one
* of {@link Opcodes#ASM4} or {@link Opcodes#ASM5}.
* @param cv
* the class visitor to which this visitor must delegate method
* calls. May be null.
*/
public ClassVisitor(final int api, final ClassVisitor cv) {
if (api != Opcodes.ASM4 && api != Opcodes.ASM5) {
throw new IllegalArgumentException();
}
this.api = api;
this.cv = cv;
}
/**
* Visits the header of the class.
*
* @param version
* the class version.
* @param access
* the class's access flags (see {@link Opcodes}). This parameter
* also indicates if the class is deprecated.
* @param name
* the internal name of the class (see
* {@link Type#getInternalName() getInternalName}).
* @param signature
* the signature of this class. May be null if the class
* is not a generic one, and does not extend or implement generic
* classes or interfaces.
* @param superName
* the internal of name of the super class (see
* {@link Type#getInternalName() getInternalName}). For
* interfaces, the super class is {@link Object}. May be
* null, but only for the {@link Object} class.
* @param interfaces
* the internal names of the class's interfaces (see
* {@link Type#getInternalName() getInternalName}). May be
* null.
*/
public void visit(int version, int access, String name, String signature,
String superName, String[] interfaces) {
if (cv != null) {
cv.visit(version, access, name, signature, superName, interfaces);
}
}
/**
* Visits the source of the class.
*
* @param source
* the name of the source file from which the class was compiled.
* May be null.
* @param debug
* additional debug information to compute the correspondance
* between source and compiled elements of the class. May be
* null.
*/
public void visitSource(String source, String debug) {
if (cv != null) {
cv.visitSource(source, debug);
}
}
/**
* Visits the enclosing class of the class. This method must be called only
* if the class has an enclosing class.
*
* @param owner
* internal name of the enclosing class of the class.
* @param name
* the name of the method that contains the class, or
* null if the class is not enclosed in a method of its
* enclosing class.
* @param desc
* the descriptor of the method that contains the class, or
* null if the class is not enclosed in a method of its
* enclosing class.
*/
public void visitOuterClass(String owner, String name, String desc) {
if (cv != null) {
cv.visitOuterClass(owner, name, desc);
}
}
/**
* Visits an annotation of the class.
*
* @param desc
* the class descriptor of the annotation class.
* @param visible
* true if the annotation is visible at runtime.
* @return a visitor to visit the annotation values, or null if
* this visitor is not interested in visiting this annotation.
*/
public AnnotationVisitor visitAnnotation(String desc, boolean visible) {
if (cv != null) {
return cv.visitAnnotation(desc, visible);
}
return null;
}
/**
* Visits an annotation on a type in the class signature.
*
* @param typeRef
* a reference to the annotated type. The sort of this type
* reference must be {@link TypeReference#CLASS_TYPE_PARAMETER
* CLASS_TYPE_PARAMETER},
* {@link TypeReference#CLASS_TYPE_PARAMETER_BOUND
* CLASS_TYPE_PARAMETER_BOUND} or
* {@link TypeReference#CLASS_EXTENDS CLASS_EXTENDS}. See
* {@link TypeReference}.
* @param typePath
* the path to the annotated type argument, wildcard bound, array
* element type, or static inner type within 'typeRef'. May be
* null if the annotation targets 'typeRef' as a whole.
* @param desc
* the class descriptor of the annotation class.
* @param visible
* true if the annotation is visible at runtime.
* @return a visitor to visit the annotation values, or null if
* this visitor is not interested in visiting this annotation.
*/
public AnnotationVisitor visitTypeAnnotation(int typeRef,
TypePath typePath, String desc, boolean visible) {
if (api < Opcodes.ASM5) {
throw new RuntimeException();
}
if (cv != null) {
return cv.visitTypeAnnotation(typeRef, typePath, desc, visible);
}
return null;
}
/**
* Visits a non standard attribute of the class.
*
* @param attr
* an attribute.
*/
public void visitAttribute(Attribute attr) {
if (cv != null) {
cv.visitAttribute(attr);
}
}
/**
* Visits information about an inner class. This inner class is not
* necessarily a member of the class being visited.
*
* @param name
* the internal name of an inner class (see
* {@link Type#getInternalName() getInternalName}).
* @param outerName
* the internal name of the class to which the inner class
* belongs (see {@link Type#getInternalName() getInternalName}).
* May be null for not member classes.
* @param innerName
* the (simple) name of the inner class inside its enclosing
* class. May be null for anonymous inner classes.
* @param access
* the access flags of the inner class as originally declared in
* the enclosing class.
*/
public void visitInnerClass(String name, String outerName,
String innerName, int access) {
if (cv != null) {
cv.visitInnerClass(name, outerName, innerName, access);
}
}
/**
* Visits a field of the class.
*
* @param access
* the field's access flags (see {@link Opcodes}). This parameter
* also indicates if the field is synthetic and/or deprecated.
* @param name
* the field's name.
* @param desc
* the field's descriptor (see {@link Type Type}).
* @param signature
* the field's signature. May be null if the field's
* type does not use generic types.
* @param value
* the field's initial value. This parameter, which may be
* null if the field does not have an initial value,
* must be an {@link Integer}, a {@link Float}, a {@link Long}, a
* {@link Double} or a {@link String} (for int,
* float, long or String fields
* respectively). This parameter is only used for static
* fields. Its value is ignored for non static fields, which
* must be initialized through bytecode instructions in
* constructors or methods.
* @return a visitor to visit field annotations and attributes, or
* null if this class visitor is not interested in visiting
* these annotations and attributes.
*/
public FieldVisitor visitField(int access, String name, String desc,
String signature, Object value) {
if (cv != null) {
return cv.visitField(access, name, desc, signature, value);
}
return null;
}
/**
* Visits a method of the class. This method must return a new
* {@link MethodVisitor} instance (or null) each time it is called,
* i.e., it should not return a previously returned visitor.
*
* @param access
* the method's access flags (see {@link Opcodes}). This
* parameter also indicates if the method is synthetic and/or
* deprecated.
* @param name
* the method's name.
* @param desc
* the method's descriptor (see {@link Type Type}).
* @param signature
* the method's signature. May be null if the method
* parameters, return type and exceptions do not use generic
* types.
* @param exceptions
* the internal names of the method's exception classes (see
* {@link Type#getInternalName() getInternalName}). May be
* null.
* @return an object to visit the byte code of the method, or null
* if this class visitor is not interested in visiting the code of
* this method.
*/
public MethodVisitor visitMethod(int access, String name, String desc,
String signature, String[] exceptions) {
if (cv != null) {
return cv.visitMethod(access, name, desc, signature, exceptions);
}
return null;
}
/**
* Visits the end of the class. This method, which is the last one to be
* called, is used to inform the visitor that all the fields and methods of
* the class have been visited.
*/
public void visitEnd() {
if (cv != null) {
cv.visitEnd();
}
}
}