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 com.oracle.java.testlibrary.OutputAnalyzer;
27
28 import javax.management.*;
29 import javax.management.remote.JMXConnector;
30 import javax.management.remote.JMXConnectorFactory;
31 import javax.management.remote.JMXServiceURL;
32
33 import java.io.IOException;
34 import java.io.PrintWriter;
35 import java.io.StringWriter;
36
37 import java.lang.management.ManagementFactory;
38
39 import java.util.HashMap;
40
41 /**
42 * Executes Diagnostic Commands on the target VM (specified by a host/port combination or a full JMX Service URL) using
43 * the JMX interface. If the target is not the current VM, the JMX Remote interface must be enabled beforehand.
44 */
45 public class JMXExecutor extends CommandExecutor {
46
47 private final MBeanServerConnection mbs;
48
49 /**
50 * Instantiates a new JMXExecutor targeting the current VM
51 */
52 public JMXExecutor() {
53 super();
54 mbs = ManagementFactory.getPlatformMBeanServer();
55 }
56
57 /**
58 * Instantiates a new JMXExecutor targeting the VM indicated by the given host/port combination or a full JMX
59 * Service URL
60 *
61 * @param target a host/port combination on the format "host:port" or a full JMX Service URL of the target VM
62 */
63 public JMXExecutor(String target) {
64 String urlStr;
65
66 if (target.matches("^\\w[\\w\\-]*(\\.[\\w\\-]+)*:\\d+$")) {
67 /* Matches "hostname:port" */
68 urlStr = String.format("service:jmx:rmi:///jndi/rmi://%s/jmxrmi", target);
69 } else if (target.startsWith("service:")) {
70 urlStr = target;
71 } else {
72 throw new IllegalArgumentException("Could not recognize target string: " + target);
73 }
74
75 try {
76 JMXServiceURL url = new JMXServiceURL(urlStr);
77 JMXConnector c = JMXConnectorFactory.connect(url, new HashMap<>());
78 mbs = c.getMBeanServerConnection();
79 } catch (IOException e) {
80 throw new CommandExecutorException("Could not initiate connection to target: " + target, e);
81 }
82 }
83
84 protected OutputAnalyzer executeImpl(String cmd) throws CommandExecutorException {
85 String stdout = "";
86 String stderr = "";
87
88 String[] cmdParts = cmd.split(" ", 2);
89 String operation = commandToMethodName(cmdParts[0]);
90 Object[] dcmdArgs = produceArguments(cmdParts);
91 String[] signature = {String[].class.getName()};
92
93 ObjectName beanName = getMBeanName();
94
95 try {
96 stdout = (String) mbs.invoke(beanName, operation, dcmdArgs, signature);
97 }
98
99 /* Failures on the "local" side, the one invoking the command. */
100 catch (ReflectionException e) {
101 Throwable cause = e.getCause();
102 if (cause instanceof NoSuchMethodException) {
103 /* We want JMXExecutor to match the behavior of the other CommandExecutors */
104 String message = "Unknown diagnostic command: " + operation;
105 stderr = exceptionTraceAsString(new IllegalArgumentException(message, e));
106 } else {
107 rethrowExecutorException(operation, dcmdArgs, e);
108 }
109 }
110
111 /* Failures on the "local" side, the one invoking the command. */
112 catch (InstanceNotFoundException | IOException e) {
113 rethrowExecutorException(operation, dcmdArgs, e);
114 }
115
116 /* Failures on the remote side, the one executing the invoked command. */
117 catch (MBeanException e) {
118 stdout = exceptionTraceAsString(e);
119 }
120
121 return new OutputAnalyzer(stdout, stderr);
122 }
123
124 private void rethrowExecutorException(String operation, Object[] dcmdArgs,
125 Exception e) throws CommandExecutorException {
126 String message = String.format("Could not invoke: %s %s", operation,
127 String.join(" ", (String[]) dcmdArgs[0]));
128 throw new CommandExecutorException(message, e);
129 }
130
131 private ObjectName getMBeanName() throws CommandExecutorException {
132 String MBeanName = "com.sun.management:type=DiagnosticCommand";
133
134 try {
135 return new ObjectName(MBeanName);
136 } catch (MalformedObjectNameException e) {
137 String message = "MBean not found: " + MBeanName;
138 throw new CommandExecutorException(message, e);
139 }
140 }
141
142 private Object[] produceArguments(String[] cmdParts) {
143 Object[] dcmdArgs = {new String[0]}; /* Default: No arguments */
144
145 if (cmdParts.length == 2) {
146 dcmdArgs[0] = cmdParts[1].split(" ");
147 }
148 return dcmdArgs;
149 }
150
151 /**
152 * Convert from diagnostic command to MBean method name
153 *
154 * Examples:
155 * help --> help
156 * VM.version --> vmVersion
157 * VM.command_line --> vmCommandLine
158 */
159 private static String commandToMethodName(String cmd) {
160 String operation = "";
161 boolean up = false; /* First letter is to be lower case */
162
163 /*
164 * If a '.' or '_' is encountered it is not copied,
165 * instead the next character will be converted to upper case
166 */
167 for (char c : cmd.toCharArray()) {
168 if (('.' == c) || ('_' == c)) {
169 up = true;
170 } else if (up) {
171 operation = operation.concat(Character.toString(c).toUpperCase());
172 up = false;
173 } else {
174 operation = operation.concat(Character.toString(c).toLowerCase());
175 }
176 }
177
178 return operation;
179 }
180
181 private static String exceptionTraceAsString(Throwable cause) {
182 StringWriter sw = new StringWriter();
183 cause.printStackTrace(new PrintWriter(sw));
184 return sw.toString();
185 }
186
187 }