Method and apparatus for locking objects using shared locks

An object-based computing system, the object-based computing system comprising:

• a memory, the memory including a plurality of address locations;
• at least one thread;
• a plurality of objects, the plurality of objects including at least one object which is accessible to the at least one thread, wherein each of the plurality of objects is associated with a corresponding address of the plurality of address locations;
• at least one lock, the at least one lock being accessible to the at least one object and being held by at least one locking thread, wherein the at least one lock can be released such that the object is not locked by any locking thread in response to a determination that the at least one locking thread is the same thread as the at least one thread;
• and
• a data structure, the data structure being arranged to associate the at least one lock with at least one corresponding address location selected from the plurality of address locations, wherein the data structure is arranged to be accessed by the at least one thread using a first value associated with the at least one object to identify the at least one lock.

A computer product for acquiring access to an object in an object-based system, the computer product comprising:

• computer code for providing a thread that attempts to acquire access to an object;
• computer code for identifying a memory address value associated with the object;
• computer code for identifying a first synchronization construct that is suitable for use in granting access to the object, wherein the first synchronization construct is identified using at least part of the memory address value;
• computer code for determining when the first synchronization construct is available;
• computer code for, when the first synchronization construct is unavailable, determining whether the thread that is attempting to acquire access to the object is already associated with the object;
• computer code for, when the thread that is attempting to acquire access to the object is already associated with the object, releasing the association such that the thread is not associated with the object;
• computer code fur associating the first synchronization construct with the object when it is determined that the first synchronization construct is available;
• and
• a computer-readable medium that stores the computer codes.

A data structure for use in a multi-threaded, object-based computing system, the data structure being arranged to be stored in a memory of the computing system, the data structure comprising:

• a plurality of index values;
• and
• a plurality of lock identifiers, each lock identifier included in the plurality of lock identifiers being arranged to identify an associated lock in the computing system, wherein the plurality of lock identifiers are associated with corresponding index values included in the plurality of index values;
• wherein the associated lock is held by a thread, and the associated lock can be released such that an object associated with the lock is not locked by any lock held by a thread in response to a determination that a requesting thread is also the thread that is holding the associated lock.

A computer-implemented method for acquiring access to an object in an object-based system, the method comprising:

• providing a thread that attempts to acquire access to an object;
• identifying a memory address value associated with the object;
• identifying a first synchronization construct that is suitable for use in granting access to the object;
• determining that the first synchronization construct is unavailable;
• when it is determined that the first synchronization construct is unavailable, determining that the thread that is attempting to acquire access to the object is already associated with the object;
• and
• when it is determined that the thread that is attempting to acquire access to the object is already associated with the object, releasing the association such that the thread is not associated with the object.

A computer program product for acquiring access to an object in an object-based system, the computer program product comprising:

• computer code for providing a thread that attempts to acquire access to an object;
• computer code for identifying a memory address value associated with the object;
• computer code for identifying a first synchronization construct that is suitable for use in granting access to the object, wherein the first synchronization construct is identified using at least part of the memory address value;
• computer code for determining whether the first synchronization construct is unavailable;
• computer code for, when it is determined that the first synchronization construct is unavailable, determining whether the thread that is attempting to acquire access to the object is already associated with the object;
• computer code for, when it is determined that the thread that is attempting to acquire access to the object is already associated with the object, releasing the association such that the thread is not associated with the object;
• and
• a computer-readable medium that stores the computer codes.