/*
* 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.pig.impl.io;
import java.io.BufferedInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.nio.ByteBuffer;
import java.nio.CharBuffer;
import java.nio.charset.Charset;
import java.nio.charset.CharsetDecoder;
import java.nio.charset.CoderResult;
import java.nio.charset.CodingErrorAction;
import org.apache.tools.bzip2r.CBZip2InputStream;
public class BufferedPositionedInputStream extends InputStream {
long pos;
InputStream in;
final int bufSize = 1024;
public BufferedPositionedInputStream(InputStream in, long pos) {
// Don't buffer a bzip stream as it will cause problems for split
// records.
if (in instanceof CBZip2InputStream) this.in = in;
else this.in = new BufferedInputStream(in, bufSize);
this.pos = pos;
}
public BufferedPositionedInputStream(InputStream in){
this(in,0);
}
@Override
public int read() throws IOException {
int c = in.read();
pos++;
return c;
}
@Override
public int read(byte b[], int off, int len) throws IOException {
int read = in.read(b, off, len);
pos += read;
return read;
}
@Override
public long skip(long n) throws IOException {
long rc = in.skip(n);
pos += rc;
return rc;
}
/**
* Returns the current position in the tracked InputStream.
*/
public long getPosition() throws IOException{
if (in instanceof CBZip2InputStream)
return ((CBZip2InputStream)in).getPos();
return pos;
}
/*
* Preallocated array for readline buffering
*/
private byte barray[] = new byte[1024];
/*
* Preallocated ByteBuffer for readline buffering
*/
private ByteBuffer bbuff = ByteBuffer.wrap(barray);
/*
* Preallocated char array for decoding bytes
*/
private char carray[] = new char[1024];
/*
* Preallocated CharBuffer for decoding bytes
*/
private CharBuffer cbuff = CharBuffer.wrap(carray);
public String readLine(Charset charset, byte delimiter) throws IOException {
CharsetDecoder decoder = charset.newDecoder();
decoder.onMalformedInput(CodingErrorAction.REPLACE);
decoder.onUnmappableCharacter(CodingErrorAction.REPLACE);
int delim = delimiter&0xff;
int rc;
int offset = 0;
StringBuilder sb = null;
CoderResult res;
while ((rc = read())!=-1) {
if (rc == delim) {
break;
}
barray[offset++] = (byte)rc;
if (barray.length == offset) {
bbuff.position(0);
bbuff.limit(barray.length);
cbuff.position(0);
cbuff.limit(carray.length);
res = decoder.decode(bbuff, cbuff, false);
if (res.isError()) {
throw new IOException("Decoding error: " + res.toString());
}
offset = bbuff.remaining();
switch (offset) {
default:
System.arraycopy(barray, bbuff.position(), barray, 0, bbuff
.remaining());
break;
case 2:
barray[1] = barray[barray.length - 1];
barray[0] = barray[barray.length - 2];
break;
case 1:
barray[0] = barray[barray.length - 1];
break;
case 0:
}
if (sb == null) {
sb = new StringBuilder(cbuff.position());
}
sb.append(carray, 0, cbuff.position());
}
}
if (sb == null) {
if (rc == -1 && offset == 0) {
// We are at EOF with nothing read
return null;
}
sb = new StringBuilder();
}
bbuff.position(0);
bbuff.limit(offset);
cbuff.position(0);
cbuff.limit(carray.length);
res = decoder.decode(bbuff, cbuff, true);
if (res.isError()) {
System.out.println("Error");
}
sb.append(carray, 0, cbuff.position());
cbuff.position(0);
res = decoder.flush(cbuff);
if (res.isError()) {
System.out.println("Error");
}
sb.append(carray, 0, cbuff.position());
return sb.toString();
}
public void close() throws IOException {
super.close();
in.close();
}
}