【HotSpot】 jps

jps(1)                         General Commands Manual                         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 indicate  the
             communications  protocol, port number, and other implementation specific
             data.

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 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 sys‐
       tem 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  plat‐
       forms.

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=<filename> argu‐
             ment).

          -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, opti‐
             mized, 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  host‐
             name  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 protocol the port indicates
             the port number for the rmiregistry on the remote host. If port is omit‐
             ted,  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(1) 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 for‐
       mat 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/jdk1.7.0/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/jdk1.7.0/demo/jfc/Java2D/Java2Demo.JAR

       3102 sun.tools.jstatd.jstatd -p 2002

SEE ALSO
          o java(1) - the Java Application Launcher

          o jstat(1) - the Java virtual machine Statistics Monitoring Tool

          o jstatd(1) - the jstat daemon

          o rmiregistry(1) - the Java Remote Object Registry

                                     18 Jul 2013                               jps(1)