ByteArrayISO8859Writer.java

// ========================================================================
// $Id: ByteArrayISO8859Writer.java,v 1.14 2004/10/23 09:03:22 gregwilkins Exp $
// Copyright 2001-2004 Mort Bay Consulting Pty. Ltd.
// ------------------------------------------------------------------------
// Licensed 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 net.lightbody.bmp.proxy.jetty.util;
import java.io.IOException;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.io.Writer;


/* ------------------------------------------------------------ */
/** Byte Array ISO 8859 writer. 
 * This class combines the features of a OutputStreamWriter for
 * ISO8859 encoding with that of a ByteArrayOutputStream.  It avoids
 * many inefficiencies associated with these standard library classes.
 * It has been optimized for standard ASCII characters.
 * 
 * @version $Revision: 1.14 $
 * @author Greg Wilkins (gregw)
 */
public class ByteArrayISO8859Writer extends Writer
{
    private byte[] _buf;
    private int _size;
    private ByteArrayOutputStream2 _bout=null;
    private OutputStreamWriter _writer=null;
    private boolean _fixed=false;

    /* ------------------------------------------------------------ */
    /** Constructor. 
     */
    public ByteArrayISO8859Writer()
    {
        _buf=ByteArrayPool.getByteArrayAtLeast(2048);
    } 
    
    /* ------------------------------------------------------------ */
    /** Constructor. 
     * @param capacity Buffer capacity
     */
    public ByteArrayISO8859Writer(int capacity)
    {
        _buf=ByteArrayPool.getByteArray(capacity);
    }
    
    /* ------------------------------------------------------------ */
    public ByteArrayISO8859Writer(byte[] buf)
    {
        _buf=buf;
        _fixed=true;
    }

    /* ------------------------------------------------------------ */
    public Object getLock()
    {
        return lock;
    }
    
    /* ------------------------------------------------------------ */
    public int size()
    {
        return _size;
    }
    
    /* ------------------------------------------------------------ */
    public int capacity()
    {
        return _buf.length;
    }

    /* ------------------------------------------------------------ */
    public int spareCapacity()
    {
        return _buf.length-_size;
    }
    
    /* ------------------------------------------------------------ */
    public void setLength(int l)
    {
        _size=l;
    }

    /* ------------------------------------------------------------ */
    public byte[] getBuf()
    {
        return _buf;
    }
    
    /* ------------------------------------------------------------ */
    public void writeTo(OutputStream out)
        throws IOException
    {
        out.write(_buf,0,_size);
    }

    /* ------------------------------------------------------------ */
    public void write(char c)
        throws IOException
    {
        ensureSpareCapacity(1);
        if (c>=0&&c<=0x7f)
            _buf[_size++]=(byte)c;
        else
        {
            char[] ca ={c};
            writeEncoded(ca,0,1);
        }
    }
    
    /* ------------------------------------------------------------ */
    public void write(char[] ca)
        throws IOException
    {
        ensureSpareCapacity(ca.length);
        for (int i=0;i<ca.length;i++)
        {
            char c=ca[i];
            if (c>=0&&c<=0x7f)
                _buf[_size++]=(byte)c;
            else
            {
                writeEncoded(ca,i,ca.length-i);
                break;
            }
        }
    }
    
    /* ------------------------------------------------------------ */
    public void write(char[] ca,int offset, int length)
        throws IOException
    {
        ensureSpareCapacity(length);
        for (int i=0;i<length;i++)
        {
            char c=ca[offset+i];
            if (c>=0&&c<=0x7f)
                _buf[_size++]=(byte)c;
            else
            {
                writeEncoded(ca,offset+i,length-i);
                break;
            }
        }
    }
    
    /* ------------------------------------------------------------ */
    public void write(String s)
        throws IOException
    {
        int length=s.length();
        ensureSpareCapacity(length);
        for (int i=0;i<length;i++)
        {
            char c=s.charAt(i);
            if (c>=0x0&&c<=0x7f)
                _buf[_size++]=(byte)c;
            else
            {
                writeEncoded(s.toCharArray(),i,length-i);
                break;
            }
        }

        
    }
    
    /* ------------------------------------------------------------ */
    public void write(String s,int offset, int length)
        throws IOException
    {
        ensureSpareCapacity(length);
        for (int i=0;i<length;i++)
        {
            char c=s.charAt(offset+i);
            if (c>=0&&c<=0x7f)
                _buf[_size++]=(byte)c;
            else
            {
                writeEncoded(s.toCharArray(),offset+i,length-i);
                break;
            }
        }
    }

    /* ------------------------------------------------------------ */
    private void writeEncoded(char[] ca,int offset, int length)
        throws IOException
    {
        if (_bout==null)
        {
            _bout = new ByteArrayOutputStream2(2*length);
            _writer = new OutputStreamWriter(_bout,StringUtil.__ISO_8859_1);
        }
        else
            _bout.reset();
        _writer.write(ca,offset,length);
        _writer.flush();
        ensureSpareCapacity(_bout.getCount());
        System.arraycopy(_bout.getBuf(),0,_buf,_size,_bout.getCount());
        _size+=_bout.getCount();
    }
    
    /* ------------------------------------------------------------ */
    public void flush()
    {}

    /* ------------------------------------------------------------ */
    public void resetWriter()
    {
        _size=0;
    }

    /* ------------------------------------------------------------ */
    public void close()
    {}

    /* ------------------------------------------------------------ */
    public void destroy()
    {
        ByteArrayPool.returnByteArray(_buf);
        _buf=null;
    }
    
    /* ------------------------------------------------------------ */
    public void ensureSpareCapacity(int n)
        throws IOException
    {
        if (_size+n>_buf.length)
        {
            if (_fixed)
                throw new IOException("Buffer overflow: "+_buf.length);
            byte[] buf = new byte[(_buf.length+n)*4/3];
            System.arraycopy(_buf,0,buf,0,_size);
            _buf=buf;
        }
    }

    /* ------------------------------------------------------------ */
    protected void finalize()
    {
        ByteArrayPool.returnByteArray(_buf);
    }

    /* ------------------------------------------------------------ */
    public byte[] getByteArray()
    {
        byte[] data=new byte[_size];
        System.arraycopy(_buf,0,data,0,_size);
        return data;
    }
    
}