jps(1)							      General Commands Manual							    jps(1)

NAME

       jps - Java Virtual Machine Process Status Tool

SYNOPSIS

       jps [options] [hostid]

DESCRIPTION

       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 typi-
       cally, but not necessarily, the operating system's process identifier for the JVM process. With no options, jps will list each Java  appli-
       cation'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 com-
       mand 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 or may not be available in future versions of the JDK.  It is not currently available on Widows
       98 and Windows ME platforms.

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 indicate the communications protocol, port number, and other implementation specific data.

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 identifiers.

       -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=<filename> argument).

       -Joption       Pass option to the java launcher called by javac. 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  opti-
		      mized,  local protocol, then port is ignored. Otherwise, treatment of the port parameter is implementation specific. For the
		      default rmi protocol the port indicates the port number for the rmiregistry on the remote host. If port is omitted, and pro-
		      tocol 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 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

SEE ALSO

       java(1) jstat(1) jstatd(1) rmiregistry(1)

								   13 June 2004 							    jps(1)