/****************************************************************
* 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. *
****************************************************************/
package org.apache.james.mime4j;
import java.io.IOException;
import java.io.InputStream;
/**
* <code>InputStream</code> used by the parser to wrap the original user
* supplied stream. This stream keeps track of the current line number and
* can also be truncated. When truncated the stream will appear to have
* reached end of file. This is used by the parser's
* {@link org.apache.james.mime4j.MimeStreamParser#stop()} method.
*
*
* @version $Id: RootInputStream.java,v 1.2 2004/10/02 12:41:10 ntherning Exp $
*/
class RootInputStream extends InputStream {
private InputStream is = null;
private int lineNumber = 1;
private int prev = -1;
private boolean truncated = false;
/**
* Creates a new <code>RootInputStream</code>.
*
* @param in the stream to read from.
*/
public RootInputStream(InputStream is) {
this.is = is;
}
/**
* Gets the current line number starting at 1
* (the number of <code>\r\n</code> read so far plus 1).
*
* @return the current line number.
*/
public int getLineNumber() {
return lineNumber;
}
/**
* Truncates this <code>InputStream</code>. After this call any
* call to {@link #read()}, {@link #read(byte[]) or
* {@link #read(byte[], int, int)} will return
* -1 as if end-of-file had been reached.
*/
public void truncate() {
this.truncated = true;
}
/**
* @see java.io.InputStream#read()
*/
public int read() throws IOException {
if (truncated) {
return -1;
}
int b = is.read();
if (prev == '\r' && b == '\n') {
lineNumber++;
}
prev = b;
return b;
}
/**
*
* @see java.io.InputStream#read(byte[], int, int)
*/
public int read(byte[] b, int off, int len) throws IOException {
if (truncated) {
return -1;
}
int n = is.read(b, off, len);
for (int i = off; i < off + n; i++) {
if (prev == '\r' && b[i] == '\n') {
lineNumber++;
}
prev = b[i];
}
return n;
}
/**
* @see java.io.InputStream#read(byte[])
*/
public int read(byte[] b) throws IOException {
return read(b, 0, b.length);
}
}