| /* |
| * Copyright (C) 2010, 2013 Google Inc. and others |
| * |
| * This program and the accompanying materials are made available under the |
| * terms of the Eclipse Distribution License v. 1.0 which is available at |
| * https://www.eclipse.org/org/documents/edl-v10.php. |
| * |
| * SPDX-License-Identifier: BSD-3-Clause |
| */ |
| |
| package org.eclipse.jgit.util.io; |
| |
| import java.io.IOException; |
| import java.io.InputStream; |
| import java.io.OutputStream; |
| |
| /** |
| * Input stream that copies data read to another output stream. |
| * |
| * This stream is primarily useful with a |
| * {@link org.eclipse.jgit.util.TemporaryBuffer}, where any data read or skipped |
| * by the caller is also duplicated into the temporary buffer. Later the |
| * temporary buffer can then be used instead of the original source stream. |
| * |
| * During close this stream copies any remaining data from the source stream |
| * into the destination stream. |
| */ |
| public class TeeInputStream extends InputStream { |
| private byte[] skipBuffer; |
| |
| private InputStream src; |
| |
| private OutputStream dst; |
| |
| /** |
| * Initialize a tee input stream. |
| * |
| * @param src |
| * source stream to consume. |
| * @param dst |
| * destination to copy the source to as it is consumed. Typically |
| * this is a {@link org.eclipse.jgit.util.TemporaryBuffer}. |
| */ |
| public TeeInputStream(InputStream src, OutputStream dst) { |
| this.src = src; |
| this.dst = dst; |
| } |
| |
| /** {@inheritDoc} */ |
| @Override |
| public int read() throws IOException { |
| byte[] b = skipBuffer(); |
| int n = read(b, 0, 1); |
| return n == 1 ? b[0] & 0xff : -1; |
| } |
| |
| /** {@inheritDoc} */ |
| @Override |
| public long skip(long count) throws IOException { |
| long skipped = 0; |
| long cnt = count; |
| final byte[] b = skipBuffer(); |
| while (0 < cnt) { |
| final int n = src.read(b, 0, (int) Math.min(b.length, cnt)); |
| if (n <= 0) |
| break; |
| dst.write(b, 0, n); |
| skipped += n; |
| cnt -= n; |
| } |
| return skipped; |
| } |
| |
| /** {@inheritDoc} */ |
| @Override |
| public int read(byte[] b, int off, int len) throws IOException { |
| if (len == 0) |
| return 0; |
| |
| int n = src.read(b, off, len); |
| if (0 < n) |
| dst.write(b, off, n); |
| return n; |
| } |
| |
| /** {@inheritDoc} */ |
| @Override |
| public void close() throws IOException { |
| byte[] b = skipBuffer(); |
| for (;;) { |
| int n = src.read(b); |
| if (n <= 0) |
| break; |
| dst.write(b, 0, n); |
| } |
| dst.close(); |
| src.close(); |
| } |
| |
| private byte[] skipBuffer() { |
| if (skipBuffer == null) |
| skipBuffer = new byte[2048]; |
| return skipBuffer; |
| } |
| } |