jcmd-java-1 (1) - Linux Manuals

Name

jcmd - Sends diagnostic command requests to a running Java Virtual Machine

SYNOPSIS

jcmd [ options ]
jcmd [ pid | main-class ] PerfCounter.print
jcmd [ pid | main-class ] command [arguments]
jcmd [ pid | main-class ] -f file

options

The command-line options. See Options.

pid

Identifies the process that receives the diagnostic command requests. The process must be a Java process. To get a list of Java processes running on a machine, use jps(1) or jcmd(1).

main-class

The main class of the process that receives the diagnostic command requests. When matching processes, any process whose main class name contains the specified string as a substring is matched. If several running Java processes share the same main class, then the diagnostic command request is sent to all these processes. To get a list of Java processes running on a machine, use jps(1) or jcmd(1).

command [arguments]

The main class of the process that receives the diagnostic command requests. When matching processes, any process whose main class name contains the specified string as a substring is matched. If several running Java processes share the same main class, then the diagnostic command request is sent to all these processes. To get a list of Java processes running on a machine, use jps(1) or jcmd(1).

Perfcounter.print

Print the performance counters available on the targeted Java processes. The list of performance counters might vary with the Java process.

-f file

Read commands from file and call them on the targeted Java processes. In file, each command must be written on a single line. Lines starting with # are ignored. Processing of file ends when all lines have been called or when a line containing the stop keyword is read.

DESCRIPTION

jcmd is a utility to send diagnostic command requests to a Java Virtual Machine supporting this feature.

Used without arguments or with the -l option, jcmd prints the list of running Java processes with their process ID, their main class and their command-line arguments.

When a process ID is specified on the command line, jcmd sends the diagnostic command request to the process with this ID.

When a main class is specified on the command line, jcmd sends the diagnostic command request to all Java processes for which the command-line argument is a substring of the Java process' main class.

With the PerfCounter.print argument, jcmd prints the performance counters available on the targeted Java processes.

With the -f option, jcmd sends to the targeted Java processes the diagnostic commands stored in the specified file.

OPTIONS

Options are mutually exclusive. Options, when used, must immediately follow the command name.

-l

Prints the list of running Java processes with their process IDs, their main classes, and their command-line arguments.

-h

Prints a help message.

-help

Prints a help message.