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      1 /*
      2  * Licensed to the Apache Software Foundation (ASF) under one or more
      3  * contributor license agreements.  See the NOTICE file distributed with
      4  * this work for additional information regarding copyright ownership.
      5  * The ASF licenses this file to You under the Apache License, Version 2.0
      6  * (the "License"); you may not use this file except in compliance with
      7  * the License.  You may obtain a copy of the License at
      8  *
      9  *      http://www.apache.org/licenses/LICENSE-2.0
     10  *
     11  *  Unless required by applicable law or agreed to in writing, software
     12  *  distributed under the License is distributed on an "AS IS" BASIS,
     13  *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     14  *  See the License for the specific language governing permissions and
     15  *  limitations under the License.
     16  *
     17  */
     18 package org.apache.bcel.classfile;
     19 
     20 import java.io.DataInput;
     21 import java.io.DataOutputStream;
     22 import java.io.IOException;
     23 import java.util.ArrayList;
     24 import java.util.Collections;
     25 import java.util.List;
     26 
     27 import org.apache.bcel.Const;
     28 
     29 /**
     30  * represents one annotation in the annotation table
     31  *
     32  * @version $Id: AnnotationEntry
     33  * @since 6.0
     34  */
     35 public class AnnotationEntry implements Node {
     36 
     37     private final int type_index;
     38     private final ConstantPool constant_pool;
     39     private final boolean isRuntimeVisible;
     40 
     41     private List<ElementValuePair> element_value_pairs;
     42 
     43     /*
     44      * Factory method to create an AnnotionEntry from a DataInput
     45      *
     46      * @param input
     47      * @param constant_pool
     48      * @param isRuntimeVisible
     49      * @return the entry
     50      * @throws IOException
     51      */
     52     public static AnnotationEntry read(final DataInput input, final ConstantPool constant_pool, final boolean isRuntimeVisible) throws IOException {
     53 
     54         final AnnotationEntry annotationEntry = new AnnotationEntry(input.readUnsignedShort(), constant_pool, isRuntimeVisible);
     55         final int num_element_value_pairs = input.readUnsignedShort();
     56         annotationEntry.element_value_pairs = new ArrayList<>();
     57         for (int i = 0; i < num_element_value_pairs; i++) {
     58             annotationEntry.element_value_pairs.add(
     59                     new ElementValuePair(input.readUnsignedShort(), ElementValue.readElementValue(input, constant_pool),
     60                     constant_pool));
     61         }
     62         return annotationEntry;
     63     }
     64 
     65     public AnnotationEntry(final int type_index, final ConstantPool constant_pool, final boolean isRuntimeVisible) {
     66         this.type_index = type_index;
     67         this.constant_pool = constant_pool;
     68         this.isRuntimeVisible = isRuntimeVisible;
     69     }
     70 
     71     public int getTypeIndex() {
     72         return type_index;
     73     }
     74 
     75     public ConstantPool getConstantPool() {
     76         return constant_pool;
     77     }
     78 
     79     public boolean isRuntimeVisible() {
     80         return isRuntimeVisible;
     81     }
     82 
     83     /**
     84      * Called by objects that are traversing the nodes of the tree implicitely defined by the contents of a Java class.
     85      * I.e., the hierarchy of methods, fields, attributes, etc. spawns a tree of objects.
     86      *
     87      * @param v Visitor object
     88      */
     89     @Override
     90     public void accept(final Visitor v) {
     91         v.visitAnnotationEntry(this);
     92     }
     93 
     94     /**
     95      * @return the annotation type name
     96      */
     97     public String getAnnotationType() {
     98         final ConstantUtf8 c = (ConstantUtf8) constant_pool.getConstant(type_index, Const.CONSTANT_Utf8);
     99         return c.getBytes();
    100     }
    101 
    102     /**
    103      * @return the annotation type index
    104      */
    105     public int getAnnotationTypeIndex() {
    106         return type_index;
    107     }
    108 
    109     /**
    110      * @return the number of element value pairs in this annotation entry
    111      */
    112     public final int getNumElementValuePairs() {
    113         return element_value_pairs.size();
    114     }
    115 
    116     /**
    117      * @return the element value pairs in this annotation entry
    118      */
    119     public ElementValuePair[] getElementValuePairs() {
    120         // TODO return List
    121         return element_value_pairs.toArray(new ElementValuePair[element_value_pairs.size()]);
    122     }
    123 
    124     public void dump(final DataOutputStream dos) throws IOException {
    125         dos.writeShort(type_index); // u2 index of type name in cpool
    126         dos.writeShort(element_value_pairs.size()); // u2 element_value pair
    127         // count
    128         for (final ElementValuePair envp : element_value_pairs) {
    129             envp.dump(dos);
    130         }
    131     }
    132 
    133     public void addElementNameValuePair(final ElementValuePair elementNameValuePair) {
    134         element_value_pairs.add(elementNameValuePair);
    135     }
    136 
    137     public String toShortString() {
    138         final StringBuilder result = new StringBuilder();
    139         result.append("@");
    140         result.append(getAnnotationType());
    141         final ElementValuePair[] evPairs = getElementValuePairs();
    142         if (evPairs.length > 0) {
    143             result.append("(");
    144             for (final ElementValuePair element : evPairs) {
    145                 result.append(element.toShortString());
    146             }
    147             result.append(")");
    148         }
    149         return result.toString();
    150     }
    151 
    152     @Override
    153     public String toString() {
    154         return toShortString();
    155     }
    156 
    157     public static AnnotationEntry[] createAnnotationEntries(final Attribute[] attrs) {
    158         // Find attributes that contain annotation data
    159         final List<AnnotationEntry> accumulatedAnnotations = new ArrayList<>(attrs.length);
    160         for (final Attribute attribute : attrs) {
    161             if (attribute instanceof Annotations) {
    162                 final Annotations runtimeAnnotations = (Annotations) attribute;
    163                 Collections.addAll(accumulatedAnnotations, runtimeAnnotations.getAnnotationEntries());
    164             }
    165         }
    166         return accumulatedAnnotations.toArray(new AnnotationEntry[accumulatedAnnotations.size()]);
    167     }
    168 }
    169