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# Java SE 6 Monitoring and Management Enhancements

## Monitoring and Management API Enhancements

> The Java Platform, Standard Edition (Java SE) provides an API to allow you to monitor and manage the Java Virtual Machine (Java VM) and other applications, in the package java.lang.management.

> The Java SE 6 platform includes the following enhancements to this API.

> - Support for `java.util.concurrent` locks has been added.

>   The `ThreadMXBean.getThreadInfo` methods have been enhanced to report the java.util.concurrent.locks.AbstractOwnableSynchronizer that a thread is waiting to acquire. The Java 2 Platform, Standard Edition (J2SE) 5.0 only reported an object monitor that a thread was blocked from entering or waiting to acquire.

>   In addition, the following new methods have been added in the ThreadMXBean interface:

> - isObjectMonitorUsageSupported()
> - isSynchronizerUsageSupported()
> - findDeadlockedThreads()
> - New classes and methods for obtaining the list of locks owned by a thread and to report which stack frame locked a monitor have been added to the `java.lang.management` package.
>   - New LockInfo class.
>   - New MonitorInfo class.
>   - New ThreadInfo methods getLockInfo(), getLockedMonitors() and getLockedSynchronizers().
>   - New ThreadMXBean methods dumpAllThreads() and getThreadInfo(long[] ids, boolean lockedMonitor, boolean lockedSynchronizers)
> - A new method, getSystemLoadAverage(), has been added to OperatingSystemMXBean to return the system load average.

## JConsole Enhancements

> The Java SE platform provides a graphical monitoring tool called JConsole. The JConsole tool implements the Java Management Extensions (JMX) API and enables you to monitor the performance of a Java VM and any instrumented applications. Introduced in J2SE 5.0, JConsole became an officially supported feature of Java SE 6.

> Some of the enhancements that have been made to the JConsole tool between these two releases are as follows.

> - JConsole Plugin support, that allows you to build your own plug-ins to run with JConsole, for example, to add a custom tab for accessing your applications' MBeans.
> - Dynamic attach capability, allowing you to connect JConsole to any application that supports the dynamic Attach API, that was also added in Java SE 6.
> - Enhanced user interface that makes data more easily accessible.
> - New Overview and VM Summary tabs, for a better presentation of general information about your Java VM.
> - The HotSpot Diagnostic MBean, which provides an API to request heap dump at runtime and also change the setting of certain VM options.
> - Improved presentation of MBeans, to make it easier to access your MBeans' operations and attributes.

## Out-of-the-Box Remote Management Enhancements

> The Java Java VM has built-in instrumentation that enables you to monitor and manage it using the JMX technology. These built-in management utilities are often referred to as out-of-the-box management tools for the Java VM. The following enhancement has been made to the out-of-the-box management utilities in this release.

> - The remote method invocation (RMI) registry has been secured using the secure sockets layer (SSL). A new management property, `com.sun.management.jmxremote.registry.ssl`, has been added to enable the use of a SSL-enabled RMI registry so that only legimate clients with the appropriate SSL certificates can obtain the connector stub.

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