001/*
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements.  See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership.  The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License.  You may obtain a copy of the License at
009 *
010 *   https://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing,
013 * software distributed under the License is distributed on an
014 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
015 * KIND, either express or implied.  See the License for the
016 * specific language governing permissions and limitations
017 * under the License.
018 */
019
020package org.apache.bcel.classfile;
021
022import java.io.DataInput;
023import java.io.DataOutputStream;
024import java.io.IOException;
025import java.util.Arrays;
026import java.util.Iterator;
027import java.util.stream.Stream;
028
029import org.apache.bcel.Const;
030import org.apache.bcel.util.Args;
031
032// The new table is used when generic types are about...
033
034//LocalVariableTable_attribute {
035//       u2 attribute_name_index;
036//       u4 attribute_length;
037//       u2 local_variable_table_length;
038//       {  u2 start_pc;
039//          u2 length;
040//          u2 name_index;
041//          u2 descriptor_index;
042//          u2 index;
043//       } local_variable_table[local_variable_table_length];
044//     }
045
046//LocalVariableTypeTable_attribute {
047//    u2 attribute_name_index;
048//    u4 attribute_length;
049//    u2 local_variable_type_table_length;
050//    {
051//      u2 start_pc;
052//      u2 length;
053//      u2 name_index;
054//      u2 signature_index;
055//      u2 index;
056//    } localVariableTypeTable[local_variable_type_table_length];
057//  }
058// J5TODO: Needs some testing !
059
060/**
061 * @since 6.0
062 */
063public class LocalVariableTypeTable extends Attribute implements Iterable<LocalVariable> {
064
065    private static final LocalVariable[] EMPTY_ARRAY = {};
066
067    private LocalVariable[] localVariableTypeTable; // variables
068
069    LocalVariableTypeTable(final int nameIdx, final int len, final DataInput input, final ConstantPool cpool) throws IOException {
070        this(nameIdx, len, (LocalVariable[]) null, cpool);
071        final int localVariableTypeTableLength = input.readUnsignedShort();
072        localVariableTypeTable = new LocalVariable[localVariableTypeTableLength];
073        for (int i = 0; i < localVariableTypeTableLength; i++) {
074            localVariableTypeTable[i] = new LocalVariable(input, cpool);
075        }
076    }
077
078    public LocalVariableTypeTable(final int nameIndex, final int length, final LocalVariable[] localVariableTypeTable, final ConstantPool constantPool) {
079        super(Const.ATTR_LOCAL_VARIABLE_TYPE_TABLE, nameIndex, length, constantPool);
080        this.localVariableTypeTable = localVariableTypeTable != null ? localVariableTypeTable : LocalVariable.EMPTY_ARRAY;
081        Args.requireU2(this.localVariableTypeTable.length, "localVariableTypeTable.length");
082    }
083
084    public LocalVariableTypeTable(final LocalVariableTypeTable c) {
085        this(c.getNameIndex(), c.getLength(), c.getLocalVariableTypeTable(), c.getConstantPool());
086    }
087
088    @Override
089    public void accept(final Visitor v) {
090        v.visitLocalVariableTypeTable(this);
091    }
092
093    /**
094     * @return deep copy of this attribute
095     */
096    @Override
097    public Attribute copy(final ConstantPool constantPool) {
098        final LocalVariableTypeTable c = (LocalVariableTypeTable) clone();
099        c.localVariableTypeTable = new LocalVariable[localVariableTypeTable.length];
100        Arrays.setAll(c.localVariableTypeTable, i -> localVariableTypeTable[i].copy());
101        c.setConstantPool(constantPool);
102        return c;
103    }
104
105    @Override
106    public final void dump(final DataOutputStream file) throws IOException {
107        super.dump(file);
108        file.writeShort(localVariableTypeTable.length);
109        for (final LocalVariable variable : localVariableTypeTable) {
110            variable.dump(file);
111        }
112    }
113
114    public final LocalVariable getLocalVariable(final int index) {
115        for (final LocalVariable variable : localVariableTypeTable) {
116            if (variable.getIndex() == index) {
117                return variable;
118            }
119        }
120        return null;
121    }
122
123    public final LocalVariable[] getLocalVariableTypeTable() {
124        return localVariableTypeTable;
125    }
126
127    public final int getTableLength() {
128        return localVariableTypeTable == null ? 0 : localVariableTypeTable.length;
129    }
130
131    @Override
132    public Iterator<LocalVariable> iterator() {
133        return Stream.of(localVariableTypeTable).iterator();
134    }
135
136    public final void setLocalVariableTable(final LocalVariable[] localVariableTable) {
137        this.localVariableTypeTable = localVariableTable != null ? localVariableTable : EMPTY_ARRAY;
138    }
139
140    /**
141     * @return String representation.
142     */
143    @Override
144    public final String toString() {
145        final StringBuilder buf = new StringBuilder();
146        for (int i = 0; i < localVariableTypeTable.length; i++) {
147            buf.append(localVariableTypeTable[i].toStringShared(true));
148            if (i < localVariableTypeTable.length - 1) {
149                buf.append('\n');
150            }
151        }
152        return buf.toString();
153    }
154}