| /** |
| * 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.apache.pulsar.utils; |
| |
| import java.io.BufferedReader; |
| import java.io.IOException; |
| import java.io.InputStreamReader; |
| import java.io.Writer; |
| import java.nio.charset.Charset; |
| import java.nio.charset.StandardCharsets; |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| public class CmdUtility { |
| private static final Logger LOG = LoggerFactory.getLogger(CmdUtility.class); |
| private static final Charset UTF_8 = StandardCharsets.UTF_8; |
| |
| /** |
| * Executes the specified string command in a separate process. STDOUT and STDERR output will be buffered to the |
| * given <code>writer</code> ( {@link Writer}) argument. |
| * |
| * @param writer |
| * stdout and stderr output |
| * @param command |
| * a specified system command |
| * @return exitValue 0: success, Non-zero: failure |
| * @throws IOException |
| */ |
| public static int exec(Writer writer, String... command) throws IOException { |
| if (LOG.isDebugEnabled()) { |
| StringBuilder sb = new StringBuilder(); |
| for (String str : command) { |
| sb.append(str).append(' '); |
| } |
| LOG.debug("command={}", sb); |
| } |
| |
| ProcessBuilder pb = new ProcessBuilder(command); |
| pb.redirectErrorStream(true); |
| Process proc = null; |
| BufferedReader reader = null; |
| try { |
| proc = pb.start(); |
| reader = new BufferedReader(new InputStreamReader(proc.getInputStream(), UTF_8)); |
| String line = null; |
| while ((line = reader.readLine()) != null) { |
| if (writer != null) { |
| writer.write(line); |
| writer.write('\n'); |
| } |
| } |
| LOG.debug("sending the command to the host"); |
| int exitValue = proc.waitFor(); |
| if (LOG.isDebugEnabled()) { |
| LOG.debug("command exit value={}", exitValue); |
| } |
| return exitValue; |
| } catch (InterruptedException e) { |
| throw new RuntimeException(e); |
| } finally { |
| if (reader != null) { |
| reader.close(); |
| } |
| if (proc != null) { |
| proc.destroy(); |
| } |
| } |
| } |
| |
| } |