1 /*
2 * Copyright (c) 2006, 2013, 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. Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26 package sun.tools.jinfo;
27
28 import java.lang.reflect.Method;
29 import java.util.Arrays;
30 import java.io.IOException;
31 import java.io.InputStream;
32
33 import com.sun.tools.attach.VirtualMachine;
34
35 import sun.tools.attach.HotSpotVirtualMachine;
36
37 /*
38 * This class is the main class for the JInfo utility. It parses its arguments
39 * and decides if the command should be satisfied using the VM attach mechanism
40 * or an SA tool.
41 */
42 public class JInfo {
43
44 public static void main(String[] args) throws Exception {
45 if (args.length == 0) {
46 usage(1); // no arguments
47 }
48
49 // First determine if we should launch SA or not
50 boolean useSA = false;
51 if (args[0].equals("-F")) {
52 // delete the -F
53 args = Arrays.copyOfRange(args, 1, args.length);
54 useSA = true;
55 } else if (args[0].equals("-flags")
56 || args[0].equals("-sysprops"))
57 {
58 if (args.length == 2) {
59 if (!args[1].matches("[0-9]+")) {
60 // If args[1] doesn't parse to a number then
61 // it must be the SA debug server
62 // (otherwise it is the pid)
63 useSA = true;
64 }
65 }
66 if (args.length == 3) {
67 // arguments include an executable and a core file
68 useSA = true;
69 }
70 } else if (!args[0].startsWith("-")) {
71 if (args.length == 2) {
72 // the only arguments are an executable and a core file
73 useSA = true;
74 }
75 } else if (args[0].equals("-h")
76 || args[0].equals("-help")) {
77 usage(0);
78 }
79
80 if (useSA) {
81 // SA only supports -flags or -sysprops
82 if (args[0].startsWith("-")) {
83 if (!(args[0].equals("-flags") || args[0].equals("-sysprops"))) {
84 usage(1);
85 }
86 }
87
88 // invoke SA which does it's own argument parsing
89 runTool(args);
90
91 } else {
92 // Now we can parse arguments for the non-SA case
93 String pid = null;
94
95 switch(args[0]) {
96 case "-flag":
97 if (args.length != 3) {
98 usage(1);
99 }
100 String option = args[1];
101 pid = args[2];
102 flag(pid, option);
103 break;
104 case "-flags":
105 if (args.length != 2) {
106 usage(1);
107 }
108 pid = args[1];
109 flags(pid);
110 break;
111 case "-sysprops":
112 if (args.length != 2) {
113 usage(1);
114 }
115 pid = args[1];
116 sysprops(pid);
117 break;
118 case "-help":
119 case "-h":
120 usage(0);
121 default:
122 if (args.length == 1) {
123 // no flags specified, we do -sysprops and -flags
124 pid = args[0];
125 sysprops(pid);
126 System.out.println();
127 flags(pid);
128 } else {
129 usage(1);
130 }
131 }
132 }
133 }
134
135 // Invoke SA tool with the given arguments
136 private static void runTool(String args[]) throws Exception {
137 String tool = "sun.jvm.hotspot.tools.JInfo";
138 // Tool not available on this platform.
139 Class<?> c = loadClass(tool);
140 if (c == null) {
141 usage(1);
142 }
143
144 // invoke the main method with the arguments
145 Class<?>[] argTypes = { String[].class } ;
146 Method m = c.getDeclaredMethod("main", argTypes);
147
148 Object[] invokeArgs = { args };
149 m.invoke(null, invokeArgs);
150 }
151
152 // loads the given class using the system class loader
153 private static Class<?> loadClass(String name) {
154 //
155 // We specify the system class loader so as to cater for development
156 // environments where this class is on the boot class path but sa-jdi.jar
157 // is on the system class path. Once the JDK is deployed then both
158 // tools.jar and sa-jdi.jar are on the system class path.
159 //
160 try {
161 return Class.forName(name, true,
162 ClassLoader.getSystemClassLoader());
163 } catch (Exception x) { }
164 return null;
165 }
166
167 private static void flag(String pid, String option) throws IOException {
168 HotSpotVirtualMachine vm = (HotSpotVirtualMachine) attach(pid);
169 String flag;
170 InputStream in;
171 int index = option.indexOf('=');
172 if (index != -1) {
173 flag = option.substring(0, index);
174 String value = option.substring(index + 1);
175 in = vm.setFlag(flag, value);
176 } else {
177 char c = option.charAt(0);
178 switch (c) {
179 case '+':
180 flag = option.substring(1);
181 in = vm.setFlag(flag, "1");
182 break;
183 case '-':
184 flag = option.substring(1);
185 in = vm.setFlag(flag, "0");
186 break;
187 default:
188 flag = option;
189 in = vm.printFlag(flag);
190 break;
191 }
192 }
193
194 drain(vm, in);
195 }
196
197 private static void flags(String pid) throws IOException {
198 HotSpotVirtualMachine vm = (HotSpotVirtualMachine) attach(pid);
199 InputStream in = vm.executeJCmd("VM.flags");
200 System.out.println("VM Flags:");
201 drain(vm, in);
202 }
203
204 private static void sysprops(String pid) throws IOException {
205 HotSpotVirtualMachine vm = (HotSpotVirtualMachine) attach(pid);
206 InputStream in = vm.executeJCmd("VM.system_properties");
207 System.out.println("Java System Properties:");
208 drain(vm, in);
209 }
210
211 // Attach to <pid>, exiting if we fail to attach
212 private static VirtualMachine attach(String pid) {
213 try {
214 return VirtualMachine.attach(pid);
215 } catch (Exception x) {
216 String msg = x.getMessage();
217 if (msg != null) {
218 System.err.println(pid + ": " + msg);
219 } else {
220 x.printStackTrace();
221 }
222 System.exit(1);
223 return null; // keep compiler happy
224 }
225 }
226
227 // Read the stream from the target VM until EOF, then detach
228 private static void drain(VirtualMachine vm, InputStream in) throws IOException {
229 // read to EOF and just print output
230 byte b[] = new byte[256];
231 int n;
232 do {
233 n = in.read(b);
234 if (n > 0) {
235 String s = new String(b, 0, n, "UTF-8");
236 System.out.print(s);
237 }
238 } while (n > 0);
239 in.close();
240 vm.detach();
241 }
242
243
244 // print usage message
245 private static void usage(int exit) {
246
247 Class<?> c = loadClass("sun.jvm.hotspot.tools.JInfo");
248 boolean usageSA = (c != null);
249
250 System.err.println("Usage:");
251 if (usageSA) {
252 System.err.println(" jinfo [option] <pid>");
253 System.err.println(" (to connect to a running process)");
254 System.err.println(" jinfo -F [option] <pid>");
255 System.err.println(" (to connect to a hung process)");
256 System.err.println(" jinfo [option] <executable> <core>");
257 System.err.println(" (to connect to a core file)");
258 System.err.println(" jinfo [option] [server_id@]<remote server IP or hostname>");
259 System.err.println(" (to connect to remote debug server)");
260 System.err.println("");
261 System.err.println("where <option> is one of:");
262 System.err.println(" for running processes:");
263 System.err.println(" -flag <name> to print the value of the named VM flag");
264 System.err.println(" -flag [+|-]<name> to enable or disable the named VM flag");
265 System.err.println(" -flag <name>=<value> to set the named VM flag to the given value");
266 System.err.println(" for running or hung processes and core files:");
267 System.err.println(" -flags to print VM flags");
268 System.err.println(" -sysprops to print Java system properties");
269 System.err.println(" <no option> to print both VM flags and system properties");
270 System.err.println(" -h | -help to print this help message");
271 } else {
272 System.err.println(" jinfo <option> <pid>");
273 System.err.println(" (to connect to a running process)");
274 System.err.println("");
275 System.err.println("where <option> is one of:");
276 System.err.println(" -flag <name> to print the value of the named VM flag");
277 System.err.println(" -flag [+|-]<name> to enable or disable the named VM flag");
278 System.err.println(" -flag <name>=<value> to set the named VM flag to the given value");
279 System.err.println(" -flags to print VM flags");
280 System.err.println(" -sysprops to print Java system properties");
281 System.err.println(" <no option> to print both VM flags and system properties");
282 System.err.println(" -h | -help to print this help message");
283 }
284
285 System.exit(exit);
286 }
287 }