1 /*
   2  * Copyright (c) 2015, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  */
  23 
  24 package com.oracle.java.testlibrary.dcmd;
  25 
  26 import java.io.File;
  27 import java.io.IOException;
  28 import java.io.PrintWriter;
  29 import java.util.Arrays;
  30 import java.util.List;
  31 
  32 /**
  33  * Executes Diagnostic Commands on the target VM (specified by pid) using the jcmd tool and its ability to read
  34  *          Diagnostic Commands from a file.
  35  */
  36 public class FileJcmdExecutor extends PidJcmdExecutor {
  37 
  38     /**
  39      * Instantiates a new FileJcmdExecutor targeting the current VM
  40      */
  41     public FileJcmdExecutor() {
  42         super();
  43     }
  44 
  45     /**
  46      * Instantiates a new FileJcmdExecutor targeting the VM indicated by the given pid
  47      *
  48      * @param target Pid of the target VM
  49      */
  50     public FileJcmdExecutor(String target) {
  51         super(target);
  52     }
  53 
  54     protected List<String> createCommandLine(String cmd) throws CommandExecutorException {
  55         File cmdFile = createTempFile();
  56         writeCommandToTemporaryFile(cmd, cmdFile);
  57 
  58         return Arrays.asList(jcmdBinary, Integer.toString(pid),
  59                 "-f", cmdFile.getAbsolutePath());
  60     }
  61 
  62     private void writeCommandToTemporaryFile(String cmd, File cmdFile) {
  63         try (PrintWriter pw = new PrintWriter(cmdFile)) {
  64             pw.println(cmd);
  65         } catch (IOException e) {
  66             String message = "Could not write to file: " + cmdFile.getAbsolutePath();
  67             throw new CommandExecutorException(message, e);
  68         }
  69     }
  70 
  71     private File createTempFile() {
  72         try {
  73             File cmdFile = File.createTempFile("input", "jcmd");
  74             cmdFile.deleteOnExit();
  75             return cmdFile;
  76         } catch (IOException e) {
  77             throw new CommandExecutorException("Could not create temporary file", e);
  78         }
  79     }
  80 
  81 }