| // Copyright 2014 The Bazel Authors. All rights reserved. |
| // |
| // Licensed 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 com.google.devtools.build.lib.util.io; |
| |
| import java.io.Closeable; |
| import java.io.IOException; |
| import java.io.OutputStream; |
| import java.io.PrintStream; |
| import java.io.PrintWriter; |
| |
| /** |
| * A pair of output streams to be used for redirecting the output and error |
| * streams of a subprocess. |
| */ |
| public class OutErr implements Closeable { |
| |
| private final OutputStream out; |
| private final OutputStream err; |
| |
| public static final OutErr SYSTEM_OUT_ERR = create(System.out, System.err); |
| |
| /** |
| * Creates a new OutErr instance from the specified output and error streams. |
| */ |
| public static OutErr create(OutputStream out, OutputStream err) { |
| return new OutErr(out, err); |
| } |
| |
| protected OutErr(OutputStream out, OutputStream err) { |
| this.out = out; |
| this.err = err; |
| } |
| |
| @Override |
| public void close() throws IOException { |
| out.close(); |
| if (out != err) { |
| err.close(); |
| } |
| } |
| |
| /** |
| * This method redirects {@link System#out} / {@link System#err} into |
| * {@code this} object. After calling this method, writing to |
| * {@link System#out} or {@link System#err} will result in |
| * {@code "System.out: " + message} or {@code "System.err: " + message} |
| * being written to the OutputStreams of {@code this} instance. |
| * |
| * Note: This method affects global variables. |
| */ |
| public void addSystemOutErrAsSource() { |
| System.setOut(new PrintStream(new LinePrefixingOutputStream("System.out: ", getOutputStream()), |
| /*autoflush=*/false)); |
| System.setErr(new PrintStream(new LinePrefixingOutputStream("System.err: ", getErrorStream()), |
| /*autoflush=*/false)); |
| } |
| |
| /** |
| * Creates a new OutErr instance from the specified stream. |
| * Writes to either the output or err of the new OutErr are written |
| * to outputStream, synchronized. |
| */ |
| public static OutErr createSynchronizedFunnel(final OutputStream outputStream) { |
| OutputStream syncOut = new OutputStream() { |
| |
| @Override |
| public synchronized void write(int b) throws IOException { |
| outputStream.write(b); |
| } |
| |
| @Override |
| public synchronized void write(byte b[]) throws IOException { |
| outputStream.write(b); |
| } |
| |
| @Override |
| public synchronized void write(byte b[], int off, int len) throws IOException { |
| outputStream.write(b, off, len); |
| } |
| |
| @Override |
| public synchronized void flush() throws IOException { |
| outputStream.flush(); |
| } |
| |
| @Override |
| public synchronized void close() throws IOException { |
| outputStream.close(); |
| } |
| }; |
| |
| return create(syncOut, syncOut); |
| } |
| |
| public OutputStream getOutputStream() { |
| return out; |
| } |
| |
| public OutputStream getErrorStream() { |
| return err; |
| } |
| |
| /** |
| * Writes the specified string to the output stream, and flushes. |
| */ |
| public void printOut(String s) { |
| PrintWriter writer = new PrintWriter(out, true); |
| writer.print(s); |
| writer.flush(); |
| } |
| |
| public void printOutLn(String s) { |
| printOut(s + "\n"); |
| } |
| |
| /** |
| * Writes the specified string to the error stream, and flushes. |
| */ |
| public void printErr(String s) { |
| PrintWriter writer = new PrintWriter(err, true); |
| writer.print(s); |
| writer.flush(); |
| } |
| |
| public void printErrLn(String s) { |
| printErr(s + "\n"); |
| } |
| |
| } |