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/*
 * Javassist, a Java-bytecode translator toolkit.
 * Copyright (C) 1999- Shigeru Chiba. All Rights Reserved.
 *
 * The contents of this file are subject to the Mozilla Public License Version
 * 1.1 (the "License"); you may not use this file except in compliance with
 * the License.  Alternatively, the contents of this file may be used under
 * the terms of the GNU Lesser General Public License Version 2.1 or later,
 * or the Apache License Version 2.0.
 *
 * Software distributed under the License is distributed on an "AS IS" basis,
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
 * for the specific language governing rights and limitations under the
 * License.
 */

package javassist.bytecode;

import java.util.Map;
import java.util.HashMap;
import java.io.IOException;
import java.io.DataInputStream;
import java.io.ByteArrayOutputStream;
import javassist.bytecode.annotation.*;

/**
 * A class representing
 * RuntimeVisibleAnnotations_attribute and
 * RuntimeInvisibleAnnotations_attribute.
 *
 * 

To obtain an AnnotationAttribute object, invoke * getAttribute(AnnotationsAttribute.visibleTag) * in ClassFile, MethodInfo, * or FieldInfo. The obtained attribute is a * runtime visible annotations attribute. * If the parameter is * AnnotationAttribute.invisibleTag, then the obtained * attribute is a runtime invisible one. * *

For example, * *

 * import javassist.bytecode.annotation.Annotation;
 *    :
 * CtMethod m = ... ;
 * MethodInfo minfo = m.getMethodInfo();
 * AnnotationsAttribute attr = (AnnotationsAttribute)
 *         minfo.getAttribute(AnnotationsAttribute.invisibleTag);
 * Annotation an = attr.getAnnotation("Author");
 * String s = ((StringMemberValue)an.getMemberValue("name")).getValue();
 * System.out.println("@Author(name=" + s + ")");
 * 
* *

This code snippet retrieves an annotation of the type Author * from the MethodInfo object specified by minfo. * Then, it prints the value of name in Author. * *

If the annotation type Author is annotated by a meta annotation: * *

 * @Retention(RetentionPolicy.RUNTIME)
 * 
* *

Then Author is visible at runtime. Therefore, the third * statement of the code snippet above must be changed into: * *

 * AnnotationsAttribute attr = (AnnotationsAttribute)
 *         minfo.getAttribute(AnnotationsAttribute.visibleTag);
 * 
* *

The attribute tag must be visibleTag instead of * invisibleTag. * *

If the member value of an annotation is not specified, the default value * is used as that member value. If so, getMemberValue() in * Annotation returns null * since the default value is not included in the * AnnotationsAttribute. It is included in the * AnnotationDefaultAttribute of the method declared in the * annotation type. * *

If you want to record a new AnnotationAttribute object, execute the * following snippet: * *

 * ClassFile cf = ... ;
 * ConstPool cp = cf.getConstPool();
 * AnnotationsAttribute attr
 *     = new AnnotationsAttribute(cp, AnnotationsAttribute.visibleTag);
 * Annotation a = new Annotation("Author", cp);
 * a.addMemberValue("name", new StringMemberValue("Chiba", cp));
 * attr.setAnnotation(a);
 * cf.addAttribute(attr);
 * cf.setVersionToJava5();
 * 
* *

The last statement is necessary if the class file was produced by * javac of JDK 1.4 or earlier. Otherwise, it is not necessary. * * @see AnnotationDefaultAttribute * @see javassist.bytecode.annotation.Annotation */ public class AnnotationsAttribute extends AttributeInfo { /** * The name of the RuntimeVisibleAnnotations attribute. */ public static final String visibleTag = "RuntimeVisibleAnnotations"; /** * The name of the RuntimeInvisibleAnnotations attribute. */ public static final String invisibleTag = "RuntimeInvisibleAnnotations"; /** * Constructs a Runtime(In)VisibleAnnotations_attribute. * * @param cp constant pool * @param attrname attribute name (visibleTag or * invisibleTag). * @param info the contents of this attribute. It does not * include attribute_name_index or * attribute_length. */ public AnnotationsAttribute(ConstPool cp, String attrname, byte[] info) { super(cp, attrname, info); } /** * Constructs an empty * Runtime(In)VisibleAnnotations_attribute. * A new annotation can be later added to the created attribute * by setAnnotations(). * * @param cp constant pool * @param attrname attribute name (visibleTag or * invisibleTag). * @see #setAnnotations(Annotation[]) */ public AnnotationsAttribute(ConstPool cp, String attrname) { this(cp, attrname, new byte[] { 0, 0 }); } /** * @param n the attribute name. */ AnnotationsAttribute(ConstPool cp, int n, DataInputStream in) throws IOException { super(cp, n, in); } /** * Returns num_annotations. */ public int numAnnotations() { return ByteArray.readU16bit(info, 0); } /** * Copies this attribute and returns a new copy. */ public AttributeInfo copy(ConstPool newCp, Map classnames) { Copier copier = new Copier(info, constPool, newCp, classnames); try { copier.annotationArray(); return new AnnotationsAttribute(newCp, getName(), copier.close()); } catch (Exception e) { throw new RuntimeException(e); } } /** * Parses the annotations and returns a data structure representing * the annotation with the specified type. See also * getAnnotations() as to the returned data structure. * * @param type the annotation type. * @return null if the specified annotation type is not included. * @see #getAnnotations() */ public Annotation getAnnotation(String type) { Annotation[] annotations = getAnnotations(); for (int i = 0; i < annotations.length; i++) { if (annotations[i].getTypeName().equals(type)) return annotations[i]; } return null; } /** * Adds an annotation. If there is an annotation with the same type, * it is removed before the new annotation is added. * * @param annotation the added annotation. */ public void addAnnotation(Annotation annotation) { String type = annotation.getTypeName(); Annotation[] annotations = getAnnotations(); for (int i = 0; i < annotations.length; i++) { if (annotations[i].getTypeName().equals(type)) { annotations[i] = annotation; setAnnotations(annotations); return; } } Annotation[] newlist = new Annotation[annotations.length + 1]; System.arraycopy(annotations, 0, newlist, 0, annotations.length); newlist[annotations.length] = annotation; setAnnotations(newlist); } /** * Parses the annotations and returns a data structure representing * that parsed annotations. Note that changes of the node values of the * returned tree are not reflected on the annotations represented by * this object unless the tree is copied back to this object by * setAnnotations(). * * @see #setAnnotations(Annotation[]) */ public Annotation[] getAnnotations() { try { return new Parser(info, constPool).parseAnnotations(); } catch (Exception e) { throw new RuntimeException(e); } } /** * Changes the annotations represented by this object according to * the given array of Annotation objects. * * @param annotations the data structure representing the * new annotations. */ public void setAnnotations(Annotation[] annotations) { ByteArrayOutputStream output = new ByteArrayOutputStream(); AnnotationsWriter writer = new AnnotationsWriter(output, constPool); try { int n = annotations.length; writer.numAnnotations(n); for (int i = 0; i < n; ++i) annotations[i].write(writer); writer.close(); } catch (IOException e) { throw new RuntimeException(e); // should never reach here. } set(output.toByteArray()); } /** * Changes the annotations. A call to this method is equivalent to: *

setAnnotations(new Annotation[] { annotation })
* * @param annotation the data structure representing * the new annotation. */ public void setAnnotation(Annotation annotation) { setAnnotations(new Annotation[] { annotation }); } /** * @param oldname a JVM class name. * @param newname a JVM class name. */ void renameClass(String oldname, String newname) { HashMap map = new HashMap(); map.put(oldname, newname); renameClass(map); } void renameClass(Map classnames) { Renamer renamer = new Renamer(info, getConstPool(), classnames); try { renamer.annotationArray(); } catch (Exception e) { throw new RuntimeException(e); } } void getRefClasses(Map classnames) { renameClass(classnames); } /** * Returns a string representation of this object. */ public String toString() { Annotation[] a = getAnnotations(); StringBuilder sbuf = new StringBuilder(); int i = 0; while (i < a.length) { sbuf.append(a[i++].toString()); if (i != a.length) sbuf.append(", "); } return sbuf.toString(); } static class Walker { byte[] info; Walker(byte[] attrInfo) { info = attrInfo; } final void parameters() throws Exception { int numParam = info[0] & 0xff; parameters(numParam, 1); } void parameters(int numParam, int pos) throws Exception { for (int i = 0; i < numParam; ++i) pos = annotationArray(pos); } final void annotationArray() throws Exception { annotationArray(0); } final int annotationArray(int pos) throws Exception { int num = ByteArray.readU16bit(info, pos); return annotationArray(pos + 2, num); } int annotationArray(int pos, int num) throws Exception { for (int i = 0; i < num; ++i) pos = annotation(pos); return pos; } final int annotation(int pos) throws Exception { int type = ByteArray.readU16bit(info, pos); int numPairs = ByteArray.readU16bit(info, pos + 2); return annotation(pos + 4, type, numPairs); } int annotation(int pos, int type, int numPairs) throws Exception { for (int j = 0; j < numPairs; ++j) pos = memberValuePair(pos); return pos; } /** * {@code element_value_paris} */ final int memberValuePair(int pos) throws Exception { int nameIndex = ByteArray.readU16bit(info, pos); return memberValuePair(pos + 2, nameIndex); } /** * {@code element_value_paris[]} */ int memberValuePair(int pos, int nameIndex) throws Exception { return memberValue(pos); } /** * {@code element_value} */ final int memberValue(int pos) throws Exception { int tag = info[pos] & 0xff; if (tag == 'e') { int typeNameIndex = ByteArray.readU16bit(info, pos + 1); int constNameIndex = ByteArray.readU16bit(info, pos + 3); enumMemberValue(pos, typeNameIndex, constNameIndex); return pos + 5; } else if (tag == 'c') { int index = ByteArray.readU16bit(info, pos + 1); classMemberValue(pos, index); return pos + 3; } else if (tag == '@') return annotationMemberValue(pos + 1); else if (tag == '[') { int num = ByteArray.readU16bit(info, pos + 1); return arrayMemberValue(pos + 3, num); } else { // primitive types or String. int index = ByteArray.readU16bit(info, pos + 1); constValueMember(tag, index); return pos + 3; } } /** * {@code const_value_index} */ void constValueMember(int tag, int index) throws Exception {} /** * {@code enum_const_value} */ void enumMemberValue(int pos, int typeNameIndex, int constNameIndex) throws Exception { } /** * {@code class_info_index} */ void classMemberValue(int pos, int index) throws Exception {} /** * {@code annotation_value} */ int annotationMemberValue(int pos) throws Exception { return annotation(pos); } /** * {@code array_value} */ int arrayMemberValue(int pos, int num) throws Exception { for (int i = 0; i < num; ++i) { pos = memberValue(pos); } return pos; } } static class Renamer extends Walker { ConstPool cpool; Map classnames; /** * Constructs a renamer. It renames some class names * into the new names specified by map. * * @param info the annotations attribute. * @param cp the constant pool. * @param map pairs of replaced and substituted class names. * It can be null. */ Renamer(byte[] info, ConstPool cp, Map map) { super(info); cpool = cp; classnames = map; } int annotation(int pos, int type, int numPairs) throws Exception { renameType(pos - 4, type); return super.annotation(pos, type, numPairs); } void enumMemberValue(int pos, int typeNameIndex, int constNameIndex) throws Exception { renameType(pos + 1, typeNameIndex); super.enumMemberValue(pos, typeNameIndex, constNameIndex); } void classMemberValue(int pos, int index) throws Exception { renameType(pos + 1, index); super.classMemberValue(pos, index); } private void renameType(int pos, int index) { String name = cpool.getUtf8Info(index); String newName = Descriptor.rename(name, classnames); if (!name.equals(newName)) { int index2 = cpool.addUtf8Info(newName); ByteArray.write16bit(index2, info, pos); } } } static class Copier extends Walker { ByteArrayOutputStream output; AnnotationsWriter writer; ConstPool srcPool, destPool; Map classnames; /** * Constructs a copier. This copier renames some class names * into the new names specified by map when it copies * an annotation attribute. * * @param info the source attribute. * @param src the constant pool of the source class. * @param dest the constant pool of the destination class. * @param map pairs of replaced and substituted class names. * It can be null. */ Copier(byte[] info, ConstPool src, ConstPool dest, Map map) { this(info, src, dest, map, true); } Copier(byte[] info, ConstPool src, ConstPool dest, Map map, boolean makeWriter) { super(info); output = new ByteArrayOutputStream(); if (makeWriter) writer = new AnnotationsWriter(output, dest); srcPool = src; destPool = dest; classnames = map; } byte[] close() throws IOException { writer.close(); return output.toByteArray(); } void parameters(int numParam, int pos) throws Exception { writer.numParameters(numParam); super.parameters(numParam, pos); } int annotationArray(int pos, int num) throws Exception { writer.numAnnotations(num); return super.annotationArray(pos, num); } int annotation(int pos, int type, int numPairs) throws Exception { writer.annotation(copyType(type), numPairs); return super.annotation(pos, type, numPairs); } int memberValuePair(int pos, int nameIndex) throws Exception { writer.memberValuePair(copy(nameIndex)); return super.memberValuePair(pos, nameIndex); } void constValueMember(int tag, int index) throws Exception { writer.constValueIndex(tag, copy(index)); super.constValueMember(tag, index); } void enumMemberValue(int pos, int typeNameIndex, int constNameIndex) throws Exception { writer.enumConstValue(copyType(typeNameIndex), copy(constNameIndex)); super.enumMemberValue(pos, typeNameIndex, constNameIndex); } void classMemberValue(int pos, int index) throws Exception { writer.classInfoIndex(copyType(index)); super.classMemberValue(pos, index); } int annotationMemberValue(int pos) throws Exception { writer.annotationValue(); return super.annotationMemberValue(pos); } int arrayMemberValue(int pos, int num) throws Exception { writer.arrayValue(num); return super.arrayMemberValue(pos, num); } /** * Copies a constant pool entry into the destination constant pool * and returns the index of the copied entry. * * @param srcIndex the index of the copied entry into the source * constant pool. * @return the index of the copied item into the destination * constant pool. */ int copy(int srcIndex) { return srcPool.copy(srcIndex, destPool, classnames); } /** * Copies a constant pool entry into the destination constant pool * and returns the index of the copied entry. That entry must be * a Utf8Info representing a class name in the L; form. * * @param srcIndex the index of the copied entry into the source * constant pool. * @return the index of the copied item into the destination * constant pool. */ int copyType(int srcIndex) { String name = srcPool.getUtf8Info(srcIndex); String newName = Descriptor.rename(name, classnames); return destPool.addUtf8Info(newName); } } static class Parser extends Walker { ConstPool pool; Annotation[][] allParams; // all parameters Annotation[] allAnno; // all annotations Annotation currentAnno; // current annotation MemberValue currentMember; // current member /** * Constructs a parser. This parser constructs a parse tree of * the annotations. * * @param info the attribute. * @param src the constant pool. */ Parser(byte[] info, ConstPool cp) { super(info); pool = cp; } Annotation[][] parseParameters() throws Exception { parameters(); return allParams; } Annotation[] parseAnnotations() throws Exception { annotationArray(); return allAnno; } MemberValue parseMemberValue() throws Exception { memberValue(0); return currentMember; } void parameters(int numParam, int pos) throws Exception { Annotation[][] params = new Annotation[numParam][]; for (int i = 0; i < numParam; ++i) { pos = annotationArray(pos); params[i] = allAnno; } allParams = params; } int annotationArray(int pos, int num) throws Exception { Annotation[] array = new Annotation[num]; for (int i = 0; i < num; ++i) { pos = annotation(pos); array[i] = currentAnno; } allAnno = array; return pos; } int annotation(int pos, int type, int numPairs) throws Exception { currentAnno = new Annotation(type, pool); return super.annotation(pos, type, numPairs); } int memberValuePair(int pos, int nameIndex) throws Exception { pos = super.memberValuePair(pos, nameIndex); currentAnno.addMemberValue(nameIndex, currentMember); return pos; } void constValueMember(int tag, int index) throws Exception { MemberValue m; ConstPool cp = pool; switch (tag) { case 'B' : m = new ByteMemberValue(index, cp); break; case 'C' : m = new CharMemberValue(index, cp); break; case 'D' : m = new DoubleMemberValue(index, cp); break; case 'F' : m = new FloatMemberValue(index, cp); break; case 'I' : m = new IntegerMemberValue(index, cp); break; case 'J' : m = new LongMemberValue(index, cp); break; case 'S' : m = new ShortMemberValue(index, cp); break; case 'Z' : m = new BooleanMemberValue(index, cp); break; case 's' : m = new StringMemberValue(index, cp); break; default : throw new RuntimeException("unknown tag:" + tag); } currentMember = m; super.constValueMember(tag, index); } void enumMemberValue(int pos, int typeNameIndex, int constNameIndex) throws Exception { currentMember = new EnumMemberValue(typeNameIndex, constNameIndex, pool); super.enumMemberValue(pos, typeNameIndex, constNameIndex); } void classMemberValue(int pos, int index) throws Exception { currentMember = new ClassMemberValue(index, pool); super.classMemberValue(pos, index); } int annotationMemberValue(int pos) throws Exception { Annotation anno = currentAnno; pos = super.annotationMemberValue(pos); currentMember = new AnnotationMemberValue(currentAnno, pool); currentAnno = anno; return pos; } int arrayMemberValue(int pos, int num) throws Exception { ArrayMemberValue amv = new ArrayMemberValue(pool); MemberValue[] elements = new MemberValue[num]; for (int i = 0; i < num; ++i) { pos = memberValue(pos); elements[i] = currentMember; } amv.setValue(elements); currentMember = amv; return pos; } } }




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