Many resources are needed to download a project. Please understand that we have to compensate our server costs. Thank you in advance. Project price only 1 $
You can buy this project and download/modify it how often you want.
/*
* Copyright (c) 2008, Harald Kuhr
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* * Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* * 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.
*
* * Neither the name of the copyright holder nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS 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 COPYRIGHT HOLDER OR 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.
*/
package com.twelvemonkeys.io;
import com.twelvemonkeys.lang.Validate;
import java.io.IOException;
import java.io.Reader;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
/**
* A Reader implementation that can read from multiple sources.
*
* @author Harald Kuhr
* @author last modified by $Author: haku $
* @version $Id: //depot/branches/personal/haraldk/twelvemonkeys/release-2/twelvemonkeys-core/src/main/java/com/twelvemonkeys/io/CompoundReader.java#2 $
*/
public class CompoundReader extends Reader {
private Reader current;
private List readers;
protected final Object finalLock;
protected final boolean markSupported;
private int currentReader;
private int markedReader;
private int mark;
private int mNext;
/**
* Create a new compound reader.
*
* @param pReaders {@code Iterator} containting {@code Reader}s,
* providing the character stream.
*
* @throws NullPointerException if {@code pReaders} is {@code null}, or
* any of the elements in the iterator is {@code null}.
* @throws ClassCastException if any element of the iterator is not a
* {@code java.io.Reader}
*/
public CompoundReader(final Iterator pReaders) {
super(Validate.notNull(pReaders, "readers"));
finalLock = pReaders; // NOTE: It's ok to sync on pReaders, as the
// reference can't change, only it's elements
readers = new ArrayList();
boolean markSupported = true;
while (pReaders.hasNext()) {
Reader reader = pReaders.next();
if (reader == null) {
throw new NullPointerException("readers cannot contain null-elements");
}
readers.add(reader);
markSupported = markSupported && reader.markSupported();
}
this.markSupported = markSupported;
current = nextReader();
}
protected final Reader nextReader() {
if (currentReader >= readers.size()) {
current = new EmptyReader();
}
else {
current = readers.get(currentReader++);
}
// NOTE: Reset mNext for every reader, and record marked reader in mark/reset methods!
mNext = 0;
return current;
}
/**
* Check to make sure that the stream has not been closed
*
* @throws IOException if the stream is closed
*/
protected final void ensureOpen() throws IOException {
if (readers == null) {
throw new IOException("Stream closed");
}
}
public void close() throws IOException {
// Close all readers
for (Reader reader : readers) {
reader.close();
}
readers = null;
}
@Override
public void mark(int pReadLimit) throws IOException {
if (pReadLimit < 0) {
throw new IllegalArgumentException("Read limit < 0");
}
// TODO: It would be nice if we could actually close some readers now
synchronized (finalLock) {
ensureOpen();
mark = mNext;
markedReader = currentReader;
current.mark(pReadLimit);
}
}
@Override
public void reset() throws IOException {
synchronized (finalLock) {
ensureOpen();
if (currentReader != markedReader) {
// Reset any reader before this
for (int i = currentReader; i >= markedReader; i--) {
readers.get(i).reset();
}
currentReader = markedReader - 1;
nextReader();
}
current.reset();
mNext = mark;
}
}
@Override
public boolean markSupported() {
return markSupported;
}
@Override
public int read() throws IOException {
synchronized (finalLock) {
int read = current.read();
if (read < 0 && currentReader < readers.size()) {
nextReader();
return read(); // In case of 0-length readers
}
mNext++;
return read;
}
}
public int read(char pBuffer[], int pOffset, int pLength) throws IOException {
synchronized (finalLock) {
int read = current.read(pBuffer, pOffset, pLength);
if (read < 0 && currentReader < readers.size()) {
nextReader();
return read(pBuffer, pOffset, pLength); // In case of 0-length readers
}
mNext += read;
return read;
}
}
@Override
public boolean ready() throws IOException {
return current.ready();
}
@Override
public long skip(long pChars) throws IOException {
synchronized (finalLock) {
long skipped = current.skip(pChars);
if (skipped == 0 && currentReader < readers.size()) {
nextReader();
return skip(pChars); // In case of 0-length readers
}
mNext += skipped;
return skipped;
}
}
}
