java.lang.management
Class MonitorInfo

java.lang.Object
  extended by java.lang.management.LockInfo
      extended by java.lang.management.MonitorInfo

public class MonitorInfo
extends LockInfo

Provides information on a monitor lock held by a thread. A monitor lock is obtained when a thread enters a synchronized block or method.

Since:
1.6

Constructor Summary
MonitorInfo(String className, int identityHashCode, int stackDepth, StackTraceElement stackFrame)
          Constructs a new MonitorInfo using the specified lock class name and identity hash code, and the given stack depth and frame.
 
Method Summary
static MonitorInfo from(CompositeData data)
           Returns a MonitorInfo instance using the values given in the supplied CompositeData object.
 int getLockedStackDepth()
          Returns the depth of the stack at which the lock was obtained.
 StackTraceElement getLockedStackFrame()
          Returns the stack frame at which the lock was obtained.
 
Methods inherited from class java.lang.management.LockInfo
getClassName, getIdentityHashCode, toString
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait
 

Constructor Detail

MonitorInfo

public MonitorInfo(String className,
                   int identityHashCode,
                   int stackDepth,
                   StackTraceElement stackFrame)
Constructs a new MonitorInfo using the specified lock class name and identity hash code, and the given stack depth and frame.

Parameters:
className - the class name of the lock object.
identityHashCode - the identity hash code of the lock object.
stackDepth - the depth of the stack at which the lock was obtained.
stackFrame - the frame of the stack at which the lock was obtained.
Throws:
IllegalArgumentException - if the stack depth and frame are inconsistent i.e. the frame is null but the depth is ≥ 0, or the frame is not null but the depth is < 0.
Method Detail

from

public static MonitorInfo from(CompositeData data)

Returns a MonitorInfo instance using the values given in the supplied CompositeData object. The composite data instance should contain the following attributes with the specified types:

NameType
classNamejava.lang.String
identityHashCodejava.lang.Integer
lockedStackDepthjava.lang.Integer
lockedStackFramejavax.management.openmbean.CompositeData

The stack trace is further described as:

NameType
classNamejava.lang.String
methodNamejava.lang.String
fileNamejava.lang.String
lineNumberjava.lang.Integer
nativeMethodjava.lang.Boolean

Parameters:
data - the composite data structure to take values from.
Returns:
a new instance containing the values from the composite data structure, or null if the data structure was also null.
Throws:
IllegalArgumentException - if the composite data structure does not match the structure outlined above.

getLockedStackDepth

public int getLockedStackDepth()
Returns the depth of the stack at which the lock was obtained. This works as an index into the array returned by ThreadInfo.getStackTrace().

Returns:
the depth of the stack at which the lock was obtained, or a negative number if this information is unavailable.

getLockedStackFrame

public StackTraceElement getLockedStackFrame()
Returns the stack frame at which the lock was obtained.

Returns:
the stack frame at which the lock was obtained, or null if this informati0on is unavailable.