Class MonitorInfo

java.lang.Object

java.lang.management.LockInfo

java.lang.management.MonitorInfo

public class MonitorInfo extends LockInfo

Information about an object monitor lock. An object monitor is locked when entering a synchronization block or method on that object.

MXBean Mapping

MonitorInfo is mapped to a CompositeData with attributes as specified in the from method.

Since:: 1.6

Constructor Summary

Constructor	Description
`MonitorInfo(String className, int identityHashCode, int stackDepth, StackTraceElement stackFrame)`	Construct a `MonitorInfo` object.

Method Summary

Modifier and Type	Method	Description
`static MonitorInfo`	`from(CompositeData cd)`	Returns a `MonitorInfo` object represented by the given `CompositeData`.
`int`	`getLockedStackDepth()`	Returns the depth in the stack trace where the object monitor was locked.
`StackTraceElement`	`getLockedStackFrame()`	Returns the stack frame that locked the object monitor.

Methods declared in class LockInfo

getClassName, getIdentityHashCode, toString

Modifier and Type	Method	Description
`String`	`getClassName()`	Returns the fully qualified name of the class of the lock object.
`int`	`getIdentityHashCode()`	Returns the identity hash code of the lock object returned from the `System.identityHashCode(Object)` method.
`String`	`toString()`	Returns a string representation of a lock.

Methods declared in class Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Modifier and Type	Method	Description
`protected Object`	`clone()`	Creates and returns a copy of this object.
`boolean`	`equals(Object obj)`	Indicates whether some other object is "equal to" this one.
`protected void`	`finalize()`	Deprecated, for removal: This API element is subject to removal in a future version. Finalization is deprecated and subject to removal in a future release.
`final Class<?>`	`getClass()`	Returns the runtime class of this `Object`.
`int`	`hashCode()`	Returns a hash code value for this object.
`final void`	`notify()`	Wakes up a single thread that is waiting on this object's monitor.
`final void`	`notifyAll()`	Wakes up all threads that are waiting on this object's monitor.
`final void`	`wait()`	Causes the current thread to wait until it is awakened, typically by being notified or interrupted.
`final void`	`wait(long timeoutMillis)`	Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.
`final void`	`wait(long timeoutMillis, int nanos)`	Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.

Constructor Details

MonitorInfo

public MonitorInfo(String className, int identityHashCode, int stackDepth, StackTraceElement stackFrame)

Construct a MonitorInfo object.

Parameters:: className - the fully qualified name of the class of the lock object.; identityHashCode - the identity hash code of the lock object.; stackDepth - the depth in the stack trace where the object monitor was locked.; stackFrame - the stack frame that locked the object monitor.
Throws:: IllegalArgumentException - if stackDepth ≥ 0 but stackFrame is null, or stackDepth < 0 but stackFrame is not null.

Method Details

getLockedStackDepth

public int getLockedStackDepth()

Returns the depth in the stack trace where the object monitor was locked. The depth is the index to the StackTraceElement array returned in the ThreadInfo.getStackTrace() method.

Returns:: the depth in the stack trace where the object monitor was locked, or a negative number if not available.

getLockedStackFrame

public StackTraceElement getLockedStackFrame()

Returns the stack frame that locked the object monitor.

Returns:: StackTraceElement that locked the object monitor, or null if not available.

from

public static MonitorInfo from(CompositeData cd)

Returns a MonitorInfo object represented by the given CompositeData. The given CompositeData must contain the following attributes as well as the attributes specified in the mapped type for the LockInfo class:

The attributes and their types the given CompositeData contains
Attribute Name	Type
lockedStackFrame	`CompositeData` for `StackTraceElement` as specified in `ThreadInfo.from(CompositeData)` method.
lockedStackDepth	`java.lang.Integer`

Parameters:: cd - CompositeData representing a MonitorInfo
Returns:: a MonitorInfo object represented by cd if cd is not null; null otherwise.
Throws:: IllegalArgumentException - if cd does not represent a MonitorInfo with the attributes described above.

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