Java example source code file (jcmd.1)

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The jcmd.1 Java example source code

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.\"     Arch: generic
.\"     Software: JDK 8
.\"     Date: 21 November 2013
.\"     SectDesc: Troubleshooting Tools
.\"     Title: jcmd.1
.\"
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.TH jcmd 1 "21 November 2013" "JDK 8" "Troubleshooting Tools"
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.SH NAME    
jcmd \- Sends diagnostic command requests to a running Java Virtual Machine (JVM)\&.
.SH SYNOPSIS    
.sp     
.nf     

\fBjcmd\fR [\fB\-l\fR|\fB\-h\fR|\fB\-help\fR]
.fi     
.nf     

\fBjcmd\fR \fIpid\fR|\fImain\-class\fR \fBPerfCounter\&.print\fR
.fi     
.nf     

\fBjcmd\fR \fIpid\fR|\fImain\-class\fR \fB\-f\fR \fIfilename\fR
.fi     
.nf     

\fBjcmd\fR \fIpid\fR|\fImain\-class\fR \fIcommand\fR[ \fIarguments\fR]
.fi     
.sp     
.SH DESCRIPTION    
The \f3jcmd\fR utility is used to send diagnostic command requests to the JVM\&. It must be used on the same machine on which the JVM is running, and have the same effective user and group identifiers that were used to launch the JVM\&.
.PP
\fINote:\fR To invoke diagnostic commands from a remote machine or with different identiers, you can use the \f3com\&.sun\&.management\&.DiagnosticCommandMBean\fR interface\&. For more information about the \f3DiagnosticCommandMBean\fR interface, see the API documentation at http://download\&.java\&.net/jdk8/docs/jre/api/management/extension/com/sun/management/DiagnosticCommandMBean\&.html
.PP
If you run \f3jcmd\fR without arguments or with the \f3-l\fR option, it prints the list of running Java process identifiers with the main class and command-line arguments that were used to launch the process\&. Running \f3jcmd\fR with the \f3-h\fR or \f3-help\fR option prints the tool\(cqs help message\&.
.PP
If you specify the processes identifier (\fIpid\fR) or the main class (\fImain-class\fR) as the first argument, \f3jcmd\fR sends the diagnostic command request to the Java process with the specified identifier or to all Java processes with the specified name of the main class\&. You can also send the diagnostic command request to all available Java processes by specifying \f30\fR as the process identifier\&. Use one of the following as the diagnostic command request:
.TP     
Perfcounter\&.print
Prints the performance counters available for the specified Java process\&. The list of performance counters might vary with the Java process\&.
.TP
-f \fIfilename\fR
.br
The name of the file from which to read diagnostic commands and send them to the specified Java process\&. Used only with the \f3-f\fR option\&. Each command in the file must be written on a single line\&. Lines starting with a number sign (\f3#\fR) are ignored\&. Processing of the file ends when all lines have been read or when a line containing the \f3stop\fR keyword is read\&.
.TP     
\fIcommand\fR [\fIarguments\fR]
The command to be sent to the specified Java process\&. The list of available diagnostic commands for a given process can be obtained by sending the \f3help\fR command to this process\&. Each diagnostic command has its own set of arguments\&. To see the description, syntax, and a list of available arguments for a command, use the name of the command as the argument for the \f3help\fR command\&.

\fINote:\fR If any arguments contain spaces, you must surround them with single or double quotation marks (\f3\&'\fR or \f3"\fR)\&. In addition, you must escape single or double quotation marks with a backslash (\f3\e\fR) to prevent the operating system shell from processing quotation marks\&. Alternatively, you can surround these arguments with single quotation marks and then with double quotation marks (or with double quotation marks and then with single quotation marks)\&.
.SH OPTIONS    
Options are mutually exclusive\&.
.TP
-f \fIfilename\fR
.br
Reads commands from the specified file\&. This option can be used only if you specify the process identifier or the main class as the first argument\&. Each command in the file must be written on a single line\&. Lines starting with a number sign (\f3#\fR) are ignored\&. Processing of the file ends when all lines have been read or when a line containing the \f3stop\fR keyword is read\&.
.TP
-h, -help
.br
Prints a help message\&.
.TP
-l
.br
Prints the list of running Java processes identifiers with the main class and command-line arguments\&.
.SH SEE\ ALSO    
.TP 0.2i    
\(bu
jps(1)
.RE
.br
'pl 8.5i
'bp