/*******************************************************************************
* Copyright (c) 2008 Scott Stanchfield.
* All rights reserved. This program and the accompanying materials
* are made available under the terms of the Eclipse Public License v1.0
* which accompanies this distribution, and is available at
* http://www.eclipse.org/legal/epl-v10.html
*
* Contributors:
* Based on the ANTLR parser generator by Terence Parr, http://antlr.org
* Ric Klaren <klaren@cs.utwente.nl>
* Scott Stanchfield - Modifications for XML Parsing
*******************************************************************************/
package com.javadude.antxr;
/**A Stream of characters fed to the lexer from a InputStream that can
* be rewound via mark()/rewind() methods.
* <p>
* A dynamic array is used to buffer up all the input characters. Normally,
* "k" characters are stored in the buffer. More characters may be stored during
* guess mode (testing syntactic predicate), or when LT(i>k) is referenced.
* Consumption of characters is deferred. In other words, reading the next
* character is not done by conume(), but deferred until needed by LA or LT.
* <p>
*
* @see com.javadude.antxr.CharQueue
*/
// SAS: added this class to handle Binary input w/ FileInputStream
import java.io.IOException;
import java.io.InputStream;
public class ByteBuffer extends InputBuffer {
// char source
transient InputStream input;
/** Create a character buffer */
public ByteBuffer(InputStream input_) {
super();
input = input_;
}
/** Ensure that the character buffer is sufficiently full */
@Override
public void fill(int amount) throws CharStreamException {
try {
syncConsume();
// Fill the buffer sufficiently to hold needed characters
while (queue.nbrEntries < amount + markerOffset) {
// Append the next character
queue.append((char)input.read());
}
}
catch (IOException io) {
throw new CharStreamIOException(io);
}
}
}