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	/*
	* Copyright (c) 2006, 2021, Oracle and/or its affiliates. All rights reserved.
	* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
	*
	* This code is free software; you can redistribute it and/or modify it
	* under the terms of the GNU General Public License version 2 only, as
	* published by the Free Software Foundation. Oracle designates this
	* particular file as subject to the "Classpath" exception as provided
	* by Oracle in the LICENSE file that accompanied this code.
	*
	* This code is distributed in the hope that it will be useful, but WITHOUT
	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
	* version 2 for more details (a copy is included in the LICENSE file that
	* accompanied this code).
	*
	* You should have received a copy of the GNU General Public License version
	* 2 along with this work; if not, write to the Free Software Foundation,
	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
	*
	* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
	* or visit www.oracle.com if you need additional information or have any
	* questions.
	*/

	package java.util.zip;

	import java.io.FilterOutputStream;
	import java.io.IOException;
	import java.io.OutputStream;

	/**
	* Implements an output stream filter for uncompressing data stored in the
	* "deflate" compression format.
	*
	* @since 1.6
	* @author David R Tribble (david@tribble.com)
	*
	* @see InflaterInputStream
	* @see DeflaterInputStream
	* @see DeflaterOutputStream
	*/

	public class InflaterOutputStream extends FilterOutputStream {
	/** Decompressor for this stream. */
	protected final Inflater inf;

	/** Output buffer for writing uncompressed data. */
	protected final byte[] buf;

	/** Temporary write buffer. */
	private final byte[] wbuf = new byte[1];

	/** Default decompressor is used. */
	private boolean usesDefaultInflater = false;

	/** true iff {@link #close()} has been called. */
	private boolean closed = false;

	/**
	* Checks to make sure that this stream has not been closed.
	*/
	private void ensureOpen() throws IOException {
	if (closed) {
	throw new IOException("Stream closed");
	}
	}

	/**
	* Creates a new output stream with a default decompressor and buffer
	* size.
	*
	* @param out output stream to write the uncompressed data to
	* @throws NullPointerException if {@code out} is null
	*/
	public InflaterOutputStream(OutputStream out) {
	this(out, out != null ? new Inflater() : null);
	usesDefaultInflater = true;
	}

	/**
	* Creates a new output stream with the specified decompressor and a
	* default buffer size.
	*
	* @param out output stream to write the uncompressed data to
	* @param infl decompressor ("inflater") for this stream
	* @throws NullPointerException if {@code out} or {@code infl} is null
	*/
	public InflaterOutputStream(OutputStream out, Inflater infl) {
	this(out, infl, 512);
	}

	/**
	* Creates a new output stream with the specified decompressor and
	* buffer size.
	*
	* @param out output stream to write the uncompressed data to
	* @param infl decompressor ("inflater") for this stream
	* @param bufLen decompression buffer size
	* @throws IllegalArgumentException if {@code bufLen <= 0}
	* @throws NullPointerException if {@code out} or {@code infl} is null
	*/
	public InflaterOutputStream(OutputStream out, Inflater infl, int bufLen) {
	super(out);

	// Sanity checks
	if (out == null)
	throw new NullPointerException("Null output");
	if (infl == null)
	throw new NullPointerException("Null inflater");
	if (bufLen <= 0)
	throw new IllegalArgumentException("Buffer size < 1");

	// Initialize
	inf = infl;
	buf = new byte[bufLen];
	}

	/**
	* Writes any remaining uncompressed data to the output stream and closes
	* the underlying output stream.
	*
	* @throws IOException if an I/O error occurs
	*/
	public void close() throws IOException {
	if (!closed) {
	// Complete the uncompressed output
	try {
	finish();
	} finally {
	out.close();
	closed = true;
	}
	}
	}

	/**
	* Flushes this output stream, forcing any pending buffered output bytes to be
	* written.
	*
	* @throws IOException if an I/O error occurs or this stream is already
	* closed
	*/
	public void flush() throws IOException {
	ensureOpen();

	// Finish decompressing and writing pending output data
	if (!inf.finished()) {
	try {
	while (!inf.finished() && !inf.needsInput()) {
	int n;

	// Decompress pending output data
	n = inf.inflate(buf, 0, buf.length);
	if (n < 1) {
	break;
	}

	// Write the uncompressed output data block
	out.write(buf, 0, n);
	}
	super.flush();
	} catch (DataFormatException ex) {
	// Improperly formatted compressed (ZIP) data
	String msg = ex.getMessage();
	if (msg == null) {
	msg = "Invalid ZLIB data format";
	}
	throw new ZipException(msg);
	}
	}
	}

	/**
	* Finishes writing uncompressed data to the output stream without closing
	* the underlying stream. Use this method when applying multiple filters in
	* succession to the same output stream.
	*
	* @throws IOException if an I/O error occurs or this stream is already
	* closed
	*/
	public void finish() throws IOException {
	ensureOpen();

	// Finish decompressing and writing pending output data
	flush();
	if (usesDefaultInflater) {
	inf.end();
	}
	}

	/**
	* Writes a byte to the uncompressed output stream.
	*
	* @param b a single byte of compressed data to decompress and write to
	* the output stream
	* @throws IOException if an I/O error occurs or this stream is already
	* closed
	* @throws ZipException if a compression (ZIP) format error occurs
	*/
	public void write(int b) throws IOException {
	// Write a single byte of data
	wbuf[0] = (byte) b;
	write(wbuf, 0, 1);
	}

	/**
	* Writes an array of bytes to the uncompressed output stream.
	*
	* @param b buffer containing compressed data to decompress and write to
	* the output stream
	* @param off starting offset of the compressed data within {@code b}
	* @param len number of bytes to decompress from {@code b}
	* @throws IndexOutOfBoundsException if {@code off < 0}, or if
	* {@code len < 0}, or if {@code len > b.length - off}
	* @throws IOException if an I/O error occurs or this stream is already
	* closed
	* @throws NullPointerException if {@code b} is null
	* @throws ZipException if a compression (ZIP) format error occurs
	*/
	public void write(byte[] b, int off, int len) throws IOException {
	// Sanity checks
	ensureOpen();
	if (b == null) {
	throw new NullPointerException("Null buffer for read");
	} else if (off < 0 \|\| len < 0 \|\| len > b.length - off) {
	throw new IndexOutOfBoundsException();
	} else if (len == 0) {
	return;
	}

	// Write uncompressed data to the output stream
	try {
	for (;;) {
	int n;

	// Fill the decompressor buffer with output data
	if (inf.needsInput()) {
	inf.setInput(b, off, len);
	// Only use input buffer once.
	len = 0;
	}

	// Decompress and write blocks of output data
	do {
	n = inf.inflate(buf, 0, buf.length);
	if (n > 0) {
	out.write(buf, 0, n);
	}
	} while (n > 0);

	// Check for missing dictionary first
	if (inf.needsDictionary()) {
	throw new ZipException("ZLIB dictionary missing");
	}
	// Check the decompressor
	if (inf.finished() \|\| (len == 0)/* no more input */) {
	break;
	}
	}
	} catch (DataFormatException ex) {
	// Improperly formatted compressed (ZIP) data
	String msg = ex.getMessage();
	if (msg == null) {
	msg = "Invalid ZLIB data format";
	}
	throw new ZipException(msg);
	}
	}
	}

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