/*
 * 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.
 */


// Sep 14, 2000:
//  Fixed serializer to report IO exception directly, instead at
//  the end of document processing.
//  Reported by Patrick Higgins <phiggins@transzap.com>


package org.apache.xml.serialize;


import java.io.IOException;
import java.io.StringWriter;
import java.io.Writer;


The printer is responsible for sending text to the output stream or writer. This class performs direct writing for efficiency. IndentPrinter supports indentation and line wrapping by extending this class. 
Author:
Assaf Arkin
Deprecated:
This class was deprecated in Xerces 2.9.0. It is recommended 
that new applications use the DOM Level 3 LSSerializer or JAXP's Transformation 
API for XML (TrAX) for serializing XML. See the Xerces documentation for more 
information.
Version:
$Revision: 699892 $ $Date: 2008-09-29 02:38:27 +0530 (Mon, 29 Sep 2008) $/**
 * The printer is responsible for sending text to the output stream
 * or writer. This class performs direct writing for efficiency.
 * {@link IndentPrinter} supports indentation and line wrapping by
 * extending this class.
 *
 * @deprecated This class was deprecated in Xerces 2.9.0. It is recommended 
 * that new applications use the DOM Level 3 LSSerializer or JAXP's Transformation 
 * API for XML (TrAX) for serializing XML. See the Xerces documentation for more 
 * information.
 * @version $Revision: 699892 $ $Date: 2008-09-29 02:38:27 +0530 (Mon, 29 Sep 2008) $
 * @author <a href="mailto:arkin@intalio.com">Assaf Arkin</a>
 */
public class Printer
{


    
The output format associated with this serializer. This will never
be a null reference. If no format was passed to the constructor,
the default one for this document type will be used. The format
object is never changed by the serializer.
/**
     * The output format associated with this serializer. This will never
     * be a null reference. If no format was passed to the constructor,
     * the default one for this document type will be used. The format
     * object is never changed by the serializer.
     */
    protected final OutputFormat _format;


    
The writer to which the document is written.
/**
     * The writer to which the document is written.
     */
    protected Writer             _writer;


    
The DTD writer. When we switch to DTD mode, all output is
accumulated in this DTD writer. When we switch out of it,
the output is obtained as a string. Must not be reset to
null until we're done with the document.
/**
     * The DTD writer. When we switch to DTD mode, all output is
     * accumulated in this DTD writer. When we switch out of it,
     * the output is obtained as a string. Must not be reset to
     * null until we're done with the document.
     */
    protected StringWriter       _dtdWriter;


    
Holds a reference to the document writer while we are
in DTD mode.
/**
     * Holds a reference to the document writer while we are
     * in DTD mode.
     */
    protected Writer          _docWriter;


    
Holds the exception thrown by the serializer.  Exceptions do not cause
the serializer to quit, but are held and one is thrown at the end.
/**
     * Holds the exception thrown by the serializer.  Exceptions do not cause
     * the serializer to quit, but are held and one is thrown at the end.
     */
    protected IOException     _exception;


    
The size of the output buffer.
/**
     * The size of the output buffer.
     */
    private static final int BufferSize = 4096;


    
Output buffer.
/**
     * Output buffer.
     */
    private final char[]  _buffer = new char[ BufferSize ];


    
Position within the output buffer.
/**
     * Position within the output buffer.
     */
    private int           _pos = 0;


    public Printer( Writer writer, OutputFormat format)
    {
        _writer = writer;
        _format = format;
        _exception = null;
        _dtdWriter = null;
        _docWriter = null;
        _pos = 0;
    }


    public IOException getException()
    {
        return _exception;
    }


    
Called by any of the DTD handlers to enter DTD mode. Once entered, all output will be accumulated in a string that can be printed as part of the document's DTD. This method may be called any number of time but will only have affect the first time it's called. To exist DTD state and get the accumulated DTD, call leaveDTD. /**
     * Called by any of the DTD handlers to enter DTD mode.
     * Once entered, all output will be accumulated in a string
     * that can be printed as part of the document's DTD.
     * This method may be called any number of time but will only
     * have affect the first time it's called. To exist DTD state
     * and get the accumulated DTD, call {@link #leaveDTD}.
     */
    public void enterDTD()
        throws IOException
    {
        // Can only enter DTD state once. Once we're out of DTD
        // state, can no longer re-enter it.
        if ( _dtdWriter == null ) {
	    flushLine( false );

			_dtdWriter = new StringWriter();
            _docWriter = _writer;
            _writer = _dtdWriter;
        }
    }


    
Called by the root element to leave DTD mode and if any
DTD parts were printer, will return a string with their
textual content.
/**
     * Called by the root element to leave DTD mode and if any
     * DTD parts were printer, will return a string with their
     * textual content.
     */
    public String leaveDTD()
        throws IOException
    {
        // Only works if we're going out of DTD mode.
        if ( _writer == _dtdWriter ) {
            flushLine( false );

			_writer = _docWriter;
            return _dtdWriter.toString();
        }
        return null;
    }


    public void printText( String text )
        throws IOException
    {
        try {
            int length = text.length();
            for ( int i = 0 ; i < length ; ++i ) {
                if ( _pos == BufferSize ) {
                    _writer.write( _buffer );
                    _pos = 0;
                }
                _buffer[ _pos ] = text.charAt( i );
                ++_pos;
            }
        } catch ( IOException except ) {
            // We don't throw an exception, but hold it
            // until the end of the document.
            if ( _exception == null )
                _exception = except;
            throw except;
        }
    }


    public void printText( StringBuffer text )
        throws IOException
    {
        try {
            int length = text.length();
            for ( int i = 0 ; i < length ; ++i ) {
                if ( _pos == BufferSize ) {
                    _writer.write( _buffer );
                    _pos = 0;
                }
                _buffer[ _pos ] = text.charAt( i );
                ++_pos;
            }
        } catch ( IOException except ) {
            // We don't throw an exception, but hold it
            // until the end of the document.
            if ( _exception == null )
                _exception = except;
            throw except;
        }
    }


    public void printText( char[] chars, int start, int length )
        throws IOException
    {
        try {
            while ( length-- > 0 ) {
                if ( _pos == BufferSize ) {
                    _writer.write( _buffer );
                    _pos = 0;
                }
                _buffer[ _pos ] = chars[ start ];
                ++start;
                ++_pos;
            }
        } catch ( IOException except ) {
            // We don't throw an exception, but hold it
            // until the end of the document.
            if ( _exception == null )
                _exception = except;
            throw except;
        }
    }


    public void printText( char ch )
        throws IOException
    {
        try {
            if ( _pos == BufferSize ) {
                _writer.write( _buffer );
                _pos = 0;
            }
            _buffer[ _pos ] = ch;
            ++_pos;
        } catch ( IOException except ) {
            // We don't throw an exception, but hold it
            // until the end of the document.
            if ( _exception == null )
                _exception = except;
            throw except;
        }
    }


    public void printSpace()
        throws IOException
    {
        try {
            if ( _pos == BufferSize ) {
                _writer.write( _buffer );
                _pos = 0;
            }
            _buffer[ _pos ] = ' ';
            ++_pos;
        } catch ( IOException except ) {
            // We don't throw an exception, but hold it
            // until the end of the document.
            if ( _exception == null )
                _exception = except;
            throw except;
        }
    }


    public void breakLine()
        throws IOException
    {
        try {
            if ( _pos == BufferSize ) {
                _writer.write( _buffer );
                _pos = 0;
            }
            _buffer[ _pos ] = '\n';
            ++_pos;
        } catch ( IOException except ) {
            // We don't throw an exception, but hold it
            // until the end of the document.
            if ( _exception == null )
                _exception = except;
            throw except;
        }
    }


    public void breakLine( boolean preserveSpace )
        throws IOException
    {
        breakLine();
    }


    public void flushLine( boolean preserveSpace )
        throws IOException
    {
        // Write anything left in the buffer into the writer.
        try {
            _writer.write( _buffer, 0, _pos );
        } catch ( IOException except ) {
            // We don't throw an exception, but hold it
            // until the end of the document.
            if ( _exception == null )
                _exception = except;
        }
        _pos = 0;
    }


    
Flush the output stream. Must be called when done printing
the document, otherwise some text might be buffered.
/**
     * Flush the output stream. Must be called when done printing
     * the document, otherwise some text might be buffered.
     */
    public void flush()
        throws IOException
    {
        try {
            _writer.write( _buffer, 0, _pos );
            _writer.flush();
        } catch ( IOException except ) {
            // We don't throw an exception, but hold it
            // until the end of the document.
            if ( _exception == null )
                _exception = except;
            throw except;
        }
        _pos = 0;
    }


    public void indent()
    {
        // NOOP
    }


    public void unindent()
    {
        // NOOP
    }


    public int getNextIndent()
    {
        return 0;
    }


    public void setNextIndent( int indent )
    {
    }


    public void setThisIndent( int indent )
    {
    }


}