cjmx is a command line JMX client intended to be used when graphical tools (e.g., JConsole, VisualVM) are unavailable. Additionally, cjmx intends to be useful in scripting environments.
cjmx is available on Maven Central using groupId com.gihub.cjmx and artifactId cjmx_2.9.2 or cjmx_2.10. An executable JAR is published using the app classifier.
- cjmx artifacts on Maven Central: http://search.maven.org/#search%7Cga%7C1%7Cg%3A%22com.github.cjmx%22
- Executable JAR using Scala 2.9.2: http://search.maven.org/remotecontent?filepath=com/github/cjmx/cjmx_2.9.2/1.0.0-M2/cjmx_2.9.2-1.0.0-M2-app.jar
- Executable JAR using Scala 2.10: http://search.maven.org/remotecontent?filepath=com/github/cjmx/cjmx_2.10/1.0.0-M2/cjmx_2.10-1.0.0-M2-app.jar
To build, run ./sbt publish-local. This will build target/cjmx.jar and install a copy to your local ivy cache.
Note: cjmx is currently cross compiled for both Scala 2.9.2 and 2.10. The 2.10 version depends on SBT 0.13 JARs, which are not available on public Maven or Ivy repositories.
To build the 2.10 version, you must first run sbt publish-local from a local checkout of SBT on branch 0.13. To only build the 2.9.2 version, run ++ 2.9.2 from the sbt
prompt before running publish-local.
Launching cjmx is done via:
java -cp $JAVA_HOME/lib/tools.jar:cjmx.jar cjmx.Main [PID]
Or, if tools.jar is on the classpath already (e.g., Apple JVM):
java -jar cjmx.jar [PID]
If a PID is specified on the command line, cjmx will attempt to connect to the local JVM with that PID; otherwise, cjmx starts in a disconnected state.
Once cjmx starts, a prompt will appear. Cjmx makes heavy use of tab completion, enabling exploration of the MBean tree. For example:
java -jar cjmx.jar 1234
> <TAB>
disconnect exit describe names select
> names 'java.<TAB>
java.lang: java.util.logging:
> describe -d 'java.lang:type=
* <value> ClassLoading Compilation
GarbageCollector Memory MemoryManager MemoryPool
OperatingSystem Runtime Threading
> names 'java.lang:type=*'
java.lang:type=ClassLoading
java.lang:type=Compilation
java.lang:type=Memory
java.lang:type=OperatingSystem
java.lang:type=Runtime
java.lang:type=Threading
> describe -d 'java.lang:type=Memory'
Object name: java.lang:type=Memory
----------------------------------
Description: Information on the management interface of the MBean
Attributes:
Verbose: boolean
Description: Verbose
ObjectPendingFinalizationCount: int
Description: ObjectPendingFinalizationCount
HeapMemoryUsage: CompositeData
Description: HeapMemoryUsage
NonHeapMemoryUsage: CompositeData
Description: NonHeapMemoryUsage
Operations:
gc(): void
Description: gc
Notifications:
javax.management.Notification
Description: MEMORY NOTIFICATION
Notification types:
java.management.memory.threshold.exceeded
java.management.memory.collection.threshold.exceeded
> mbeans 'java.lang:type=Memory' select *
java.lang:type=Memory
---------------------
Verbose: false
ObjectPendingFinalizationCount: 0
HeapMemoryUsage:
committed: 110432256
init: 0
max: 2130051072
used: 63307880
NonHeapMemoryUsage:
committed: 140849152
init: 24317952
max: 318767104
used: 121815008
Alternatively, cjmx can run a series of commands and then terminate. This is done by specifying each command as a program argument. For example:
java -jar cjmx.jar 1234 "describe 'java.lang:type=Memory'" "mbeans 'java.lang:type=Memory' select *"
Object name: java.lang:type=Memory
----------------------------------
Description: Information on the management interface of the MBean
Attributes:
Verbose: boolean
ObjectPendingFinalizationCount: int
HeapMemoryUsage: CompositeData
NonHeapMemoryUsage: CompositeData
Operations:
gc(): void
Notifications:
javax.management.Notification
java.lang:type=Memory
---------------------
Verbose: false
ObjectPendingFinalizationCount: 0
HeapMemoryUsage:
committed: 110432256
init: 0
max: 2130051072
used: 76943832
NonHeapMemoryUsage:
committed: 140980224
init: 24317952
max: 318767104
used: 122049448
All commands have help information available by typing "help" in the console.