1/* 2 * reserved comment block 3 * DO NOT REMOVE OR ALTER! 4 */ 5/* 6 * Licensed to the Apache Software Foundation (ASF) under one or more 7 * contributor license agreements. See the NOTICE file distributed with 8 * this work for additional information regarding copyright ownership. 9 * The ASF licenses this file to You under the Apache License, Version 2.0 10 * (the "License"); you may not use this file except in compliance with 11 * the License. You may obtain a copy of the License at 12 * 13 * http://www.apache.org/licenses/LICENSE-2.0 14 * 15 * Unless required by applicable law or agreed to in writing, software 16 * distributed under the License is distributed on an "AS IS" BASIS, 17 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 18 * See the License for the specific language governing permissions and 19 * limitations under the License. 20 */ 21 22package com.sun.org.apache.bcel.internal.classfile; 23 24import com.sun.org.apache.bcel.internal.Constants; 25import com.sun.org.apache.bcel.internal.generic.Type; 26import java.io.*; 27 28/** 29 * This class represents the field info structure, i.e., the representation 30 * for a variable in the class. See JVM specification for details. 31 * 32 * @author <A HREF="mailto:markus.dahm@berlin.de">M. Dahm</A> 33 */ 34public final class Field extends FieldOrMethod { 35 /** 36 * Initialize from another object. Note that both objects use the same 37 * references (shallow copy). Use clone() for a physical copy. 38 */ 39 public Field(Field c) { 40 super(c); 41 } 42 43 /** 44 * Construct object from file stream. 45 * @param file Input stream 46 */ 47 Field(DataInputStream file, ConstantPool constant_pool) 48 throws IOException, ClassFormatException 49 { 50 super(file, constant_pool); 51 } 52 53 /** 54 * @param access_flags Access rights of field 55 * @param name_index Points to field name in constant pool 56 * @param signature_index Points to encoded signature 57 * @param attributes Collection of attributes 58 * @param constant_pool Array of constants 59 */ 60 public Field(int access_flags, int name_index, int signature_index, 61 Attribute[] attributes, ConstantPool constant_pool) 62 { 63 super(access_flags, name_index, signature_index, attributes, constant_pool); 64 } 65 66 /** 67 * Called by objects that are traversing the nodes of the tree implicitely 68 * defined by the contents of a Java class. I.e., the hierarchy of methods, 69 * fields, attributes, etc. spawns a tree of objects. 70 * 71 * @param v Visitor object 72 */ 73 public void accept(Visitor v) { 74 v.visitField(this); 75 } 76 77 /** 78 * @return constant value associated with this field (may be null) 79 */ 80 public final ConstantValue getConstantValue() { 81 for(int i=0; i < attributes_count; i++) 82 if(attributes[i].getTag() == Constants.ATTR_CONSTANT_VALUE) 83 return (ConstantValue)attributes[i]; 84 85 return null; 86 } 87 88 /** 89 * Return string representation close to declaration format, 90 * `public static final short MAX = 100', e.g.. 91 * 92 * @return String representation of field, including the signature. 93 */ 94 public final String toString() { 95 String name, signature, access; // Short cuts to constant pool 96 97 // Get names from constant pool 98 access = Utility.accessToString(access_flags); 99 access = access.equals("")? "" : (access + " "); 100 signature = Utility.signatureToString(getSignature()); 101 name = getName(); 102 103 StringBuffer buf = new StringBuffer(access + signature + " " + name); 104 ConstantValue cv = getConstantValue(); 105 106 if(cv != null) 107 buf.append(" = " + cv); 108 109 for(int i=0; i < attributes_count; i++) { 110 Attribute a = attributes[i]; 111 112 if(!(a instanceof ConstantValue)) 113 buf.append(" [" + a.toString() + "]"); 114 } 115 116 return buf.toString(); 117 } 118 119 /** 120 * @return deep copy of this field 121 */ 122 public final Field copy(ConstantPool constant_pool) { 123 return (Field)copy_(constant_pool); 124 } 125 126 /** 127 * @return type of field 128 */ 129 public Type getType() { 130 return Type.getReturnType(getSignature()); 131 } 132} 133