compositebytearrayrelativereader.java

mina是以Java实现的一个开源的网络程序框架

/*
 *  Licensed to the Apache Software Foundation (ASF) under one
 *  or more contributor license agreements.  See the NOTICE file
 *  distributed with this work for additional information
 *  regarding copyright ownership.  The ASF licenses this file
 *  to you under the Apache License, Version 2.0 (the
 *  "License"); you may not use this file except in compliance
 *  with the License.  You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing,
 *  software distributed under the License is distributed on an
 *  "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 *  KIND, either express or implied.  See the License for the
 *  specific language governing permissions and limitations
 *  under the License.
 *
 */
package org.apache.mina.util.byteaccess;


import org.apache.mina.core.buffer.IoBuffer;


/**
 * Provides restricted, relative, read-only access to the bytes in a
 * <code>CompositeByteArray</code>. Using this interface has the advantage
 * that it can be automatically determined when a component
 * <code>ByteArray</code> can no longer be read, and thus components can be
 * automatically freed. This makes it easier to use pooling for underlying
 * <code>ByteArray</code>s.
 * 
 * @author The Apache MINA Project ([e-mail])
 * @version $Rev$, $Date$
 */
public class CompositeByteArrayRelativeReader extends CompositeByteArrayRelativeBase implements IoRelativeReader
{

    /**
     * Whether or not to free component <code>CompositeByteArray</code>s when
     * the cursor moves past them.
     */
    private final boolean autoFree;

    /**
     * 
     * Creates a new instance of CompositeByteArrayRelativeReader.
     *
     * @param cba
     *  The backing ByteArray
     * @param autoFree
     *  If data should be freed once it has been passed in the list
     */
    public CompositeByteArrayRelativeReader( CompositeByteArray cba, boolean autoFree )
    {
        super( cba );
        this.autoFree = autoFree;
    }


    @Override
    protected void cursorPassedFirstComponent()
    {
        if ( autoFree )
        {
            cba.removeFirst().free();
        }
    }


    /**
     * @inheritDoc
     */
    public void skip( int length )
    {
        cursor.skip( length );
    }


    /**
     * @inheritDoc
     */
    public ByteArray slice( int length )
    {
        return cursor.slice( length );
    }

    /**
     * Returns the byte at the current position in the buffer
     * 
     */
    public byte get()
    {
        return cursor.get();
    }

    /**
     * places the data starting at current position into the
     * supplied {@link IoBuffer}
     */
    public void get( IoBuffer bb )
    {
        cursor.get( bb );
    }


    /**
     * @inheritDoc
     */
    public short getShort()
    {
        return cursor.getShort();
    }


    /**
     * @inheritDoc
     */
    public int getInt()
    {
        return cursor.getInt();
    }


    /**
     * @inheritDoc
     */
    public long getLong()
    {
        return cursor.getLong();
    }


    /**
     * @inheritDoc
     */
    public float getFloat()
    {
        return cursor.getFloat();
    }


    /**
     * @inheritDoc
     */
    public double getDouble()
    {
        return cursor.getDouble();
    }


    /**
     * @inheritDoc
     */
    public char getChar()
    {
        return cursor.getChar();
    }

}