jps

jps(1)                                                                  jps(1)



NAME
       jps - Java Virtual Machine Process Status Tool

SYNOPSIS
       jps [ options ] [ hostid ]



PARAMETERS
       options
          Command-line options.

       hostid
          The  host identifier of the host for which the process report should
          be generated. The hostid may include optional components that  indi‐
          cate the communications protocol, port number, and other implementa‐
          tion specific data.

DESCRIPTION
       The jps tool lists  the  instrumented  HotSpot  Java  Virtual  Machines
       (JVMs)  on the target system. The tool is limited to reporting informa‐
       tion on JVMs for which it has the access permissions.

       If jps is run without specifying a hostid, it  will  look  for  instru‐
       mented  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 argu‐
       ments 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 per‐
       missions granted to the principal running the command. The command will
       only list the JVMs for which the principle has access rights as  deter‐
       mined 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.

OPTIONS
       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.

       -q Suppress  the output of the class name, JAR file name, and arguments
          passed to the main method, producing only a list of local VM identi‐
          fiers.

       -m Output  the  arguments  passed to the main method. The output may be
          null for embedded JVMs.

       -l Output the full package name for the application's main class or the
          full path name to the application's JAR file.

       -v Output the arguments passed to the JVM.

       -V Output  the  arguments passed to the JVM through the flags file (the
          .hotspotrc file or the file specified  by  the  -XX:Flags=
          argument).

       -Joption
          Pass  option  to  the  java  launcher  called  by  jps. For example,
          -J-Xms48m sets the startup memory to 48 megabytes. It  is  a  common
          convention  for  -J  to  pass options to the underlying VM executing
          applications written in Java.

   HOST IDENTIFIER
          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
             The communications protocol. If the protocol  is  omitted  and  a
             hostname  is  not  specified,  the default protocol is a platform
             specific, optimized, local protocol. If the protocol  is  omitted
             and a hostname is specified, then the default protocol is rmi.

          hostname
             A  hostname or IP address indicating the target host. If hostname
             is omitted, then the target host is the local host.

          port
             The default port for communicating with the remote server. If the
             hostname is omitted or the protocol specifies an optimized, local
             protocol, then port is ignored. Otherwise, treatment of the  port
             parameter  is implementation specific. For the default rmi proto‐
             col the port indicates the port number for the rmiregistry on the
             remote host. If port is omitted, and protocol indicates rmi, then
             the default rmiregistry port (1099) is used.

          servername
             The treatment of this parameter depends  on  the  implementation.
             For the optimized, local protocol, this field is ignored. For the
             rmi protocol, this parameter is a string representing the name of
             the  RMI  remote object on the remote host. See the -n option for
             the jstatd command.

OUTPUT FORMAT
       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.


EXAMPLES
       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 reg‐
       istry 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


SEE ALSO
          o java - the Java Application Launcher

          o jstat - the Java virtual machine Statistics Monitoring Tool

          o jstatd - the jstat daemon

          o rmiregistry - the Java Remote Object Registry


                                  06 Aug 2006                           jps(1)