Java tutorial
/* * 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.jclouds.compute.domain; import static com.google.common.base.Preconditions.checkNotNull; import java.io.Closeable; import java.io.IOException; import java.io.InputStream; import java.io.OutputStream; import com.google.common.base.Supplier; import com.google.common.io.Closeables; /** * A current connection to an exec'd command. Please ensure you call {@link ExecChannel#close} * * @author Adrian Cole */ public class ExecChannel implements Closeable { private final OutputStream input; private final InputStream output; private final InputStream error; private final Supplier<Integer> exitStatus; private final Closeable closer; public ExecChannel(OutputStream input, InputStream output, InputStream error, Supplier<Integer> exitStatus, Closeable closer) { this.input = checkNotNull(input, "input"); this.output = checkNotNull(output, "output"); this.error = checkNotNull(error, "error"); this.exitStatus = checkNotNull(exitStatus, "exitStatus"); this.closer = checkNotNull(closer, "closer"); } /** * * @return the command's {@code stdin} stream. */ public OutputStream getInput() { return input; } /** * * @return the command's {@code stderr} stream. */ public InputStream getError() { return error; } /** * * @return the command's {@code stdout} stream. */ public InputStream getOutput() { return output; } /** * * @return the exit status of the command if it was received, or {@code null} if this information * was not received. */ public Supplier<Integer> getExitStatus() { return exitStatus; } /** * closes resources associated with this channel. */ @Override public void close() throws IOException { Closeables.closeQuietly(input); Closeables.closeQuietly(output); Closeables.closeQuietly(error); closer.close(); } }