jps [ options ] [ hostid ]
options
hostid
The jps tool lists the instrumented HotSpot Java Virtual Machines (JVMs) on the target system. The tool is limited to reporting information on JVMs for which it has the access permissions.
If jps is run without specifying a hostid, it will look for instrumented JVMs on the local host. If started with a hostid, it will look for JVMs on the indicated host, using the specified protocol and port. A jstatd process is assumed to be running on the target host.
The jps command will report the local VM identifier, or lvmid, for each instrumented JVM found on the target system. The lvmid is typically, but not necessarily, the operating system's process identifier for the JVM process. With no options, jps will list each Java application's lvmid followed by the short form of the application's class name or jar file name. The short form of the class name or JAR file name omits the class's package information or the JAR files path information.
The jps command uses the java launcher
to find the class name and arguments passed to the main
method.
If the target JVM is started with a custom launcher, the
class name (or JAR file name) and the arguments to the main
method will not be available. In this case, the jps command will
output the string Unknown for the class name or JAR file name and
for the arguments to the main method.
The list of JVMs produced by the jps command may be limited by the permissions granted to the principal running the command. The command will only list the JVMs for which the principle has access rights as determined by operating system specific access control mechanisms.
NOTE: This utility is unsupported and may not be available in future versions of the JDK. It is not currently available on Windows 98 and Windows ME platforms.
The jps command supports a number of options that modify the output of the command. These options are subject to change or removal in the future.
main
method, producing only
a list of local VM identifiers.
The host identifier, or hostid is a string that indicates the target system. The syntax of the hostid string largely corresponds to the syntax of a URI:
[protocol:][[//]hostname][:port][/servername]
protocol
hostname
port
servername
The output of the jps command follows the following pattern:
lvmid [ [ classname | JARfilename | "Unknown"] [ arg* ] [ jvmarg* ] ]
Where all output tokens are separated by white space. An arg that
includes embedded white space will introduce ambiguity when attempting to
map arguments to their actual positional parameters.
NOTE: You are advised not to write scripts to parse jps output since the format may change in
future releases. If you choose to write scripts that parse jps output, expect to modify them for future releases of this tool.
This section provides examples of the jps command.
Listing the instrumented JVMs on the local host:
jps
18027 Java2Demo.JAR
18032 jps
18005 jstat
Listing the instrumented JVMs on a remote host:
This example assumes that the jstat server and either the its internal RMI registry or a separate external rmiregistry process are running on the remote host on the default port (port 1099). It also assumes that the local host has appropriate permissions to access the remote host. This example also includes the -l option to output the long form of the class names or JAR file names.
jps -l remote.domain
3002 /opt/j2sdk1.5.0/demo/jfc/Java2D/Java2Demo.JAR
2857 sun.tools.jstatd.jstatd
Listing the instrumented JVMs on a remote host with a non-default port for the RMI registry
This example assumes that the jstatd server, with an internal RMI registry bound to port 2002, is running on the remote host. This example also uses the -m option to include the arguments passed to the main method of each of the listed Java applications.
jps -m remote.domain:2002
3002 /opt/j2sdk1.5.0/demo/jfc/Java2D/Java2Demo.JAR
3102 sun.tools.jstatd.jstatd -p 2002
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