Reader for the ISO-8859-1 encoding.
/*
* 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.
*/
import java.io.IOException;
import java.io.InputStream;
import java.io.Reader;
/**
* <p>
* Reader for the ISO-8859-1 encoding.
* </p>
*
* @xerces.internal
*
* @author Michael Glavassevich, IBM
*
* @version $Id: Latin1Reader.java 446716 2006-09-15 20:28:48Z mrglavas $
*/
public class Latin1Reader extends Reader {
//
// Constants
//
/** Default byte buffer size (2048). */
public static final int DEFAULT_BUFFER_SIZE = 2048;
//
// Data
//
/** Input stream. */
protected final InputStream fInputStream;
/** Byte buffer. */
protected final byte[] fBuffer;
//
// Constructors
//
/**
* Constructs an ISO-8859-1 reader from the specified input stream using the
* default buffer size.
*
* @param inputStream
* The input stream.
*/
public Latin1Reader(InputStream inputStream) {
this(inputStream, DEFAULT_BUFFER_SIZE);
} // <init>(InputStream)
/**
* Constructs an ISO-8859-1 reader from the specified input stream and buffer
* size.
*
* @param inputStream
* The input stream.
* @param size
* The initial buffer size.
*/
public Latin1Reader(InputStream inputStream, int size) {
this(inputStream, new byte[size]);
} // <init>(InputStream, int)
/**
* Constructs an ISO-8859-1 reader from the specified input stream and buffer.
*
* @param inputStream
* The input stream.
* @param buffer
* The byte buffer.
*/
public Latin1Reader(InputStream inputStream, byte[] buffer) {
fInputStream = inputStream;
fBuffer = buffer;
} // <init>(InputStream, byte[])
//
// 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 255 (<tt>0x00-0xff</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 {
return fInputStream.read();
} // 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) {
ch[offset + i] = (char) (fBuffer[i] & 0xff);
}
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 Latin1Reader
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