001/*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements.  See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License.  You may obtain a copy of the License at
008 *
009 *      http://www.apache.org/licenses/LICENSE-2.0
010 *
011 *  Unless required by applicable law or agreed to in writing, software
012 *  distributed under the License is distributed on an "AS IS" BASIS,
013 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 *  See the License for the specific language governing permissions and
015 *  limitations under the License.
016 */
017
018package org.apache.bcel.classfile;
019
020import java.io.DataInput;
021import java.io.DataOutputStream;
022import java.io.IOException;
023
024import org.apache.bcel.Const;
025
026/**
027 * Entry of the parameters table.
028 *
029 * @see <a href="http://docs.oracle.com/javase/specs/jvms/se8/html/jvms-4.html#jvms-4.7.24">
030 * The class File Format : The MethodParameters Attribute</a>
031 * @since 6.0
032 */
033public class MethodParameter implements Cloneable {
034
035    /** Index of the CONSTANT_Utf8_info structure in the constant_pool table representing the name of the parameter */
036    private int name_index;
037
038    /** The access flags */
039    private int access_flags;
040
041    public MethodParameter() {
042    }
043
044    /**
045     * Construct object from input stream.
046     *
047     * @param input Input stream
048     * @throws java.io.IOException
049     * @throws ClassFormatException
050     */
051    MethodParameter(final DataInput input) throws IOException {
052        name_index = input.readUnsignedShort();
053        access_flags = input.readUnsignedShort();
054    }
055
056    public int getNameIndex() {
057        return name_index;
058    }
059
060    public void setNameIndex(final int name_index) {
061        this.name_index = name_index;
062    }
063
064    /**
065     * Returns the name of the parameter.
066     */
067    public String getParameterName(final ConstantPool constant_pool) {
068        if (name_index == 0) {
069            return null;
070        }
071        return ((ConstantUtf8) constant_pool.getConstant(name_index, Const.CONSTANT_Utf8)).getBytes();
072       }
073
074    public int getAccessFlags() {
075        return access_flags;
076    }
077
078    public void setAccessFlags(final int access_flags) {
079        this.access_flags = access_flags;
080    }
081
082    public boolean isFinal() {
083        return (access_flags & Const.ACC_FINAL) != 0;
084    }
085
086    public boolean isSynthetic() {
087        return (access_flags & Const.ACC_SYNTHETIC) != 0;
088    }
089
090    public boolean isMandated() {
091        return (access_flags & Const.ACC_MANDATED) != 0;
092    }
093
094    public void accept(final Visitor v) {
095        v.visitMethodParameter(this);
096    }
097
098    /**
099     * Dump object to file stream on binary format.
100     *
101     * @param file Output file stream
102     * @throws IOException
103     */
104    public final void dump(final DataOutputStream file) throws IOException {
105        file.writeShort(name_index);
106        file.writeShort(access_flags);
107    }
108
109    /**
110     * @return deep copy of this object
111     */
112    public MethodParameter copy() {
113        try {
114            return (MethodParameter) clone();
115        } catch (final CloneNotSupportedException e) {
116            // TODO should this throw?
117        }
118        return null;
119    }
120}