/*
* The Apache Software License, Version 1.1
*
*
* Copyright (c) 2000-2002 The Apache Software Foundation. All rights
* reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* 3. The end-user documentation included with the redistribution,
* if any, must include the following acknowledgment:
* "This product includes software developed by the
* Apache Software Foundation (http://www.apache.org/)."
* Alternately, this acknowledgment may appear in the software itself,
* if and wherever such third-party acknowledgments normally appear.
*
* 4. The names "Xerces" and "Apache Software Foundation" must
* not be used to endorse or promote products derived from this
* software without prior written permission. For written
* permission, please contact apache@apache.org.
*
* 5. Products derived from this software may not be called "Apache",
* nor may "Apache" appear in their name, without prior written
* permission of the Apache Software Foundation.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
* ====================================================================
*
* This software consists of voluntary contributions made by many
* individuals on behalf of the Apache Software Foundation and was
* originally based on software copyright (c) 1999, International
* Business Machines, Inc., http://www.apache.org. For more
* information on the Apache Software Foundation, please see
* <http://www.apache.org/>.
*/
package com.sun.org.apache.xerces.internal.impl.io;
import java.io.InputStream;
import java.io.IOException;
import java.io.Reader;
import java.util.Locale;
import com.sun.org.apache.xerces.internal.util.MessageFormatter;
import com.sun.org.apache.xerces.internal.impl.msg.XMLMessageFormatter;
/**
* A simple ASCII byte reader. This is an optimized reader for reading
* byte streams that only contain 7-bit ASCII characters.
*
* @author Andy Clark, IBM
*
* @version $Id: ASCIIReader.java,v 1.7 2004/03/04 19:27:13 mrglavas Exp $
*/
public class ASCIIReader
extends Reader {
//
// Constants
//
/** Default byte buffer size (2048). */
public static final int DEFAULT_BUFFER_SIZE = 2048;
//
// Data
//
/** Input stream. */
protected InputStream fInputStream;
/** Byte buffer. */
protected byte[] fBuffer;
// message formatter; used to produce localized
// exception messages
private MessageFormatter fFormatter = null;
//Locale to use for messages
private Locale fLocale = null;
//
// Constructors
//
/**
* Constructs an ASCII reader from the specified input stream
* using the default buffer size.
*
* @param inputStream The input stream.
* @param messageFormatter the MessageFormatter to use to message reporting.
* @param locale the Locale for which messages are to be reported
*/
public ASCIIReader(InputStream inputStream, MessageFormatter messageFormatter,
Locale locale) {
this(inputStream, DEFAULT_BUFFER_SIZE, messageFormatter, locale);
} // <init>(InputStream, MessageFormatter, Locale)
/**
* Constructs an ASCII reader from the specified input stream
* and buffer size.
*
* @param inputStream The input stream.
* @param size The initial buffer size.
* @param messageFormatter the MessageFormatter to use to message reporting.
* @param locale the Locale for which messages are to be reported
*/
public ASCIIReader(InputStream inputStream, int size,
MessageFormatter messageFormatter, Locale locale) {
fInputStream = inputStream;
fBuffer = new byte[size];
fFormatter = messageFormatter;
fLocale = locale;
} // <init>(InputStream,int, MessageFormatter, Locale)
//
// Reader methods
//
/**
* Read a single character. This method will block until a character is
* available, an I/O error occurs, or the end of the stream is reached.
*
* <p> Subclasses that intend to support efficient single-character input
* should override this method.
*
* @return The character read, as an integer in the range 0 to 127
* (<tt>0x00-0x7f</tt>), or -1 if the end of the stream has
* been reached
*
* @exception IOException If an I/O error occurs
*/
public int read() throws IOException {
int b0 = fInputStream.read();
if (b0 >= 0x80) {
throw new MalformedByteSequenceException(fFormatter,
fLocale, XMLMessageFormatter.XML_DOMAIN,
"InvalidASCII", new Object [] {Integer.toString(b0)});
}
return b0;
} // read():int
/**
* Read characters into a portion of an array. This method will block
* until some input is available, an I/O error occurs, or the end of the
* stream is reached.
*
* @param ch Destination buffer
* @param offset Offset at which to start storing characters
* @param length Maximum number of characters to read
*
* @return The number of characters read, or -1 if the end of the
* stream has been reached
*
* @exception IOException If an I/O error occurs
*/
public int read(char ch[], int offset, int length) throws IOException {
if (length > fBuffer.length) {
length = fBuffer.length;
}
int count = fInputStream.read(fBuffer, 0, length);
for (int i = 0; i < count; i++) {
int b0 = fBuffer[i];
if (b0 < 0) {
throw new MalformedByteSequenceException(fFormatter,
fLocale, XMLMessageFormatter.XML_DOMAIN,
"InvalidASCII", new Object [] {Integer.toString(b0 & 0x0FF)});
}
ch[offset + i] = (char)b0;
}
return count;
} // read(char[],int,int)
/**
* Skip characters. This method will block until some characters are
* available, an I/O error occurs, or the end of the stream is reached.
*
* @param n The number of characters to skip
*
* @return The number of characters actually skipped
*
* @exception IOException If an I/O error occurs
*/
public long skip(long n) throws IOException {
return fInputStream.skip(n);
} // skip(long):long
/**
* Tell whether this stream is ready to be read.
*
* @return True if the next read() is guaranteed not to block for input,
* false otherwise. Note that returning false does not guarantee that the
* next read will block.
*
* @exception IOException If an I/O error occurs
*/
public boolean ready() throws IOException {
return false;
} // ready()
/**
* Tell whether this stream supports the mark() operation.
*/
public boolean markSupported() {
return fInputStream.markSupported();
} // markSupported()
/**
* Mark the present position in the stream. Subsequent calls to reset()
* will attempt to reposition the stream to this point. Not all
* character-input streams support the mark() operation.
*
* @param readAheadLimit Limit on the number of characters that may be
* read while still preserving the mark. After
* reading this many characters, attempting to
* reset the stream may fail.
*
* @exception IOException If the stream does not support mark(),
* or if some other I/O error occurs
*/
public void mark(int readAheadLimit) throws IOException {
fInputStream.mark(readAheadLimit);
} // mark(int)
/**
* Reset the stream. If the stream has been marked, then attempt to
* reposition it at the mark. If the stream has not been marked, then
* attempt to reset it in some way appropriate to the particular stream,
* for example by repositioning it to its starting point. Not all
* character-input streams support the reset() operation, and some support
* reset() without supporting mark().
*
* @exception IOException If the stream has not been marked,
* or if the mark has been invalidated,
* or if the stream does not support reset(),
* or if some other I/O error occurs
*/
public void reset() throws IOException {
fInputStream.reset();
} // reset()
/**
* Close the stream. Once a stream has been closed, further read(),
* ready(), mark(), or reset() invocations will throw an IOException.
* Closing a previously-closed stream, however, has no effect.
*
* @exception IOException If an I/O error occurs
*/
public void close() throws IOException {
fInputStream.close();
} // close()
} // class ASCIIReader
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