/*
* Copyright 2005-2006 Sun Microsystems, Inc. All Rights Reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Sun designates this
* particular file as subject to the "Classpath" exception as provided
* by Sun in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
* CA 95054 USA or visit www.sun.com if you need additional information or
* have any questions.
*/
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.PrintStream;
import java.lang.management.ManagementFactory;
import java.lang.reflect.Method;
import java.util.ArrayList;
import java.util.Arrays;
import sun.tools.attach.HotSpotVirtualMachine;
import com.sun.tools.attach.AttachNotSupportedException;
import com.sun.tools.attach.VirtualMachine;
import com.sun.tools.javac.code.Attribute.Array;
/*
* This class is the main class for the JStack utility. It parses its arguments
* and decides if the command should be executed by the SA JStack tool or by
* obtained the thread dump from a target process using the VM attach mechanism
*/
public class JStack
{
public static void main(String[] args) throws Exception
{
disableSystemExitCall();
final String stdoutRedirectFileName = System.getProperty("java.io.tmpdir")
+ File.separator +"jstacktrace.out.log";
final PrintStream originalOut = System.out;
boolean useSA = false;
boolean mixed = false;
boolean locks = false;
Runtime.getRuntime().addShutdownHook(new Thread()
{
public void run()
{
if(isStopping)
{
return;
}
JStack.isStopping = true;
isStopping = true;
for(int i = 0; i < 50; i++)
{
System.out.flush();
try
{
Thread.sleep(10);
} catch (InterruptedException e)
{
System.err.println(e.toString());
}
}
System.out.close();
System.setOut(originalOut);
String[] argsToJCallGrind = new String[2];
argsToJCallGrind[0] = stdoutRedirectFileName;
argsToJCallGrind[1] = loadedSA;
try
{
JCallGrind.main(argsToJCallGrind);
}
catch (IOException e)
{
e.printStackTrace();
System.err.println("ERROR : Please make sure the current dir is writeable");
}
}
});
if (args.length == 0)
{
usage(); // no arguments
}
Double samplesPerSecond = 0.2;
// Parse the options (arguments starting with "-" )
int optionCount = 0;
while (optionCount < args.length)
{
String arg = args[optionCount];
if (!arg.startsWith("-"))
{
break;
}
if (arg.equals("-F"))
{
useSA = true;
} else
{
if (arg.equals("-m"))
{
mixed = true;
}
else
{
if (arg.equals("-l"))
{
locks = true;
}
else if(arg.startsWith("-c"))
{
try
{
samplesPerSecond = Double.valueOf(arg.substring(2));
}
catch(Exception ex)
{
usage();
}
}
else
{
usage();
}
}
}
optionCount++;
}
// mixed stack implies SA tool
if (mixed)
{
useSA = true;
}
// Next we check the parameter count. If there are two parameters
// we assume core file and executable so we use SA.
int paramCount = args.length - optionCount;
if (paramCount == 0 || paramCount > 3)
{
usage();
}
if (paramCount == 3)
{
useSA = true;
}
else
{
// If we can't parse it as a pid then it must be debug server
if (!args[optionCount].matches("[0-9]+"))
{
useSA = true;
}
else
{
}
}
System.out.println("trace log is stored at : " + stdoutRedirectFileName);
System.out.println("press CTRL+C when you want to stop this session");
System.setOut(
new PrintStream(
new BufferedOutputStream(
new FileOutputStream(stdoutRedirectFileName))));
// now execute using the SA JStack tool or the built-in thread dumper
if (useSA)
{
// parameters (<pid> or <exe> <core>
String params[] = new String[paramCount];
for (int i = optionCount; i < args.length; i++)
{
params[i - optionCount] = args[i];
}
while(!isStopping)
{
runJStackTool(mixed, locks, params);
long miliseconds = Double.valueOf((Math.random()*2000 / samplesPerSecond)).longValue();
Thread.sleep(miliseconds);
}
} else
{
// pass -l to thread dump operation to get extra lock info
String pid = args[optionCount];
String params[];
if (locks)
{
params = new String[]
{ "-l" };
} else
{
params = new String[0];
}
while(!isStopping)
{
runThreadDump(pid, params);
long miliseconds = Double.valueOf((Math.random()*2000 / samplesPerSecond)).longValue();
Thread.sleep(miliseconds);
}
}
}
// SA JStack tool
private static void runJStackTool(boolean mixed, boolean locks,
String args[]) throws Exception
{
Class<?> cl = loadSAClass();
if (cl == null)
{
usage(); // SA not available
}
// JStack tool also takes -m and -l arguments
if (mixed)
{
args = prepend("-m", args);
}
if (locks)
{
args = prepend("-l", args);
}
Class[] argTypes = { String[].class };
Method m = cl.getDeclaredMethod("main", argTypes);
Object[] invokeArgs =
{ args };
// maskStderr();
try
{
m.invoke(null, invokeArgs);
}catch(Exception ex){}
// unMaskStderr();
}
// Returns sun.jvm.hotspot.tools.JStack if available, otherwise null.
private static Class loadSAClass()
{
//
// Attempt to load JStack class - we specify the system class
// loader so as to cater for development environments where
// this class is on the boot class path but sa-jdi.jar is on
// the system class path. Once the JDK is deployed then both
// tools.jar and sa-jdi.jar are on the system class path.
//
loadedSA = "true";
try
{
return Class.forName("sun.jvm.hotspot.tools.JStack", true,
ClassLoader.getSystemClassLoader());
} catch (Exception x)
{
// x.printStackTrace();
}
return null;
}
// Attach to pid and perform a thread dump
private static void runThreadDump(String pid, String args[])
throws Exception
{
VirtualMachine vm = null;
PrintStream originalErr = System.err;
try
{
// Work around the swallowed error when running on Linux
// which complains windows attacher could not be found
vm = VirtualMachine.attach(pid);
}
catch (Exception x)
{
String msg = x.getMessage();
if (msg != null)
{
System.err.println(pid + ": " + msg);
} else
{
x.printStackTrace();
}
if ((x instanceof AttachNotSupportedException)
&& (loadSAClass() != null))
{
System.err.println("The -F option can be used when the target "
+ "process is not responding");
}
System.exit(1);
}
// Cast to HotSpotVirtualMachine as this is implementation specific
// method.
InputStream in = ((HotSpotVirtualMachine) vm)
.remoteDataDump((Object[]) args);
// read to EOF and just print output
byte b[] = new byte[256];
int n;
do
{
n = in.read(b);
if (n > 0)
{
String s = new String(b, 0, n, "UTF-8");
System.out.print(s);
}
} while (n > 0);
in.close();
vm.detach();
}
// return a new string array with arg as the first element
private static String[] prepend(String arg, String args[])
{
String[] newargs = new String[args.length + 1];
newargs[0] = arg;
System.arraycopy(args, 0, newargs, 1, args.length);
return newargs;
}
// print usage message
private static void usage()
{
System.err.println("Usage:");
System.err.println(" java -jar JCallgrind.jar [-l] <pid>");
System.err.println(" (to connect to running process)");
if (loadSAClass() != null)
{
System.err.println(" java -jar JCallgrind.jar -F [-m] [-l] <pid>");
System.err.println(" (to connect to a hung process)");
System.err.println(" java -jar JCallgrind.jar [-m] [-l] <executable> <core>");
System.err.println(" (to connect to a core file)");
System.err
.println(" java -jar JCallgrind.jar [-m] [-l] [server_id@]<remote server IP or hostname>");
System.err.println(" (to connect to a remote debug server)");
}
System.err.println("");
System.err.println("Options:");
if (loadSAClass() != null)
{
System.err
.println(" -F to force a thread dump. Use when java -jar JCallgrind.jar <pid> does not respond"
+ " (process is hung)");
System.err
.println(" -m to print both java and native frames (mixed mode)");
}
System.err
.println(" -l long listing. Prints additional information about locks");
System.err.println(" -h or -help to print this help message");
System.exit(1);
}
public static boolean isStopping = false;
public static PrintStream stdErr = System.err;
public static void maskStderr()
{
System.setErr(new PrintStream(
new OutputStream(){
@Override
public void write(int b) throws IOException
{
// no action
}}
));
}
public static void unMaskStderr()
{
System.setErr(stdErr);
}
private static void disableSystemExitCall()
{
final SecurityManager securityManager = new SecurityManager() {
public void checkPermission(java.security.Permission permission) {
// Forbid only exit status 1
// If you want to forbid any kind of halt, just use "exitVM"
if (permission.getName().contains("exitVM.0")) {
throw new SecurityException(
"System.exit calls not allowed!");
}
}
};
System.setSecurityManager(securityManager);
}
private static String loadedSA = "false";
}