Monitoring Tools

Java VisualVM

Java VisualVM is a new monitoring and profiling tool for troubleshooting Java applications It incorporates various technologies, including jvmstat and JMX, as well as CPU and memory profiling, to provide one easy-to-use integrated visualization tool 

Developers can rapidly create their own extensions using a public API, and may share them with the community on a central repository

Display local and remote Java applications

Display application configuration and runtime environment

Monitor application memory consumption and runtime behavior

Monitor application threads

Profile application performance or analyze memory allocation (Local applications only)

Create and display thread dumps

Create and browse heap dumps

Analyze core dumps

Analyze applications offline

Get additional plugins contributed by the community

Write and share your own plugins

JConsole

Launch a GUI to monitor and manage Java applications and Java VMs on a local or remote machine

Connection to Java process, host, or JMX agent

Graphical overview of CPU usage, heap memory, threads, classes

Summary of key data, for example, uptime, compilation time, objects pending finalization, and more

Memory statistics, including garbage collection

Request garbage collection

Thread statistics

Deadlock detection

Class statistics

Tree structure of all platform and application MBeans

Set the value of an MBean attribute

Invoke operation on an MBean, for example, perform a heap dump

Subscribe to notification for an MBean

Information about the virtual machine, the compiler, the operating system

Pass flags to VM on which JConsole is running

jps

List instrumented Java virtual machines

jstat

Display performance statistics for an instrumented Java VM:

Behavior of the class loader

Behavior of the HotSpot Just-in-Time compiler, totals and by method

Behavior of the GC heap

Behavior and sizes of the generation areas

jstatd

Monitor for creation and termination of instrumented HotSpot Java VMs

Provide an interface for remote monitoring tools to attach to Java VMs

Debugging Tools
HPROF profiler
Writes class profiling information to a file or a socket, in ASCII or binary.
Heap allocation profiling.
Heap dump.
CPU usage - for threads, methods.
Monitor contention profiling.
To invoke the HPROF tool: java -agentlib:hprof ToBeProfiledClass
To print the complete list of options: java -agentlib:hprof=help
jdb
Launch a simple interactive command-line debugger.
Display Java objects and primitive values.
List currently running threads.
Dump the current thread stack.
Set breakpoints.
Step through execution.
Examine exceptions.
jhat
Parse a binary heap dump, launch a web browser, and present standard queries.
Execute standard queries, for example, classes, objects, class instances, reference chains from object rootset, reachable objects, and more.
Turn on or off object allocation tracking.
Turn on or off object reference tracking.
Specify objects to exclude from "reachable objects" query.
Pass flags to the Java VM on which jhat is running.
Develop custom queries with buit-in Object Query Language.
Compare objects in two dumps.
jinfo
Print command line flags and system properties for a running process, from a core file, or for a remote debug server.
Dynamically set, unset, or change the value of certain Java VM flags for a process.
jmap
Print shared object mappings for a process, a core file, or a remote debug server.
Dump the Java heap (all objects or only live objects) of a process, a core file, or a remote debug server in binary format to a file.
Force the Java heap dump of a process if the process does not respond.
Print a heap summary for a process, a core file, or a remote debug server.
Print a histogram (all objects or only live objects) of a process, a core file, or a remote debug server.
Print information on objects awaiting finalization.
Print class loader statistics of the permanent generation.
Pass flags to the VM.
jsadebugd
Serviceability Agent Debug Daemon, which acts as debug server.
Attach to a Java process or a core file.
Remote clients can attach to the server using RMI.
jstack
Print stack traces of threads for a process, core file, or remote debug server
Print information about concurrent locks for a process, core file, or remote debug serverForce the stack dump for a process if the process does not respond

Scripting Tools

jrunscript

Command-line script shell: Evaluate or execute a script in interactive or batch mode.

Pass flag to the VM.

Set Java system properties.