Lock

The Lock activity is used to make a key in a space read-only. When a key is locked, only the lock owner can modify the data that is stored with that key.

The owner of the lock is the thread that created the lock. Locks are automatically cleared if the member that created them leaves the metaspace.
Note: Ensure that the numbers of Lock and Unlock operations for one tuple are consistent within a thread.

General

In the General tab, you can specify the activity name, a space connection, and whether to enable the Async Operation option.

The following table describes the fields in the General tab of the Lock activity:

Field Module Property? Description
Name No Specifies the name to be displayed as the label for the activity in the process.
Space Connection Yes Click the icon to select a space connection that defines how the application joins the space.

Tuples are locked in the space with the defined distribution role of the selected space connection.

If no matching space connections are found, click Create Shared Resource to create one. See Creating a Metaspace Connection for details.

Async Operation No Select this check box to enable the asynchronous operation. After this check box is selected, the SpaceResultHandler activity is triggered. This check box is not selected by default.

Description

In the Description tab, you can enter a short description for the Lock activity.

Advanced

In the Advanced tab, you can specify the advanced configurations.

The following table describes the fields in the Advanced tab of the Lock activity:

Field Module Property? Description
Lock Wait(milliseconds) Yes Specifies the amount of time in milliseconds the Lock operation waits for the lock to be cleared if the tuple has been locked.

The value of the Lock Wait(milliseconds) field overwrites the value in the Lock wait (milliseconds) field, which is specified in the Advanced tab of the Space shared resource. The default value of -2 or a null value indicates that the value set in the Lock wait (milliseconds) Lock field is not overwritten.

Forget Yes Indicates whether tuples are returned.
Note: If you select this check box, no tuples are returned. This check box is not selected by default.
Space Result Handler Key Yes Specifies the key of the SpaceResultHandler activity, which is used for the asynchronous operation.

This field is displayed only when you select the Async Operation check box in the General tab of the Lock activity.

Input

In the Input tab, you have to provide the key values of tuples to be locked in the space.
Note: You have to input all the keys specified in the space. Nullable keys are optional.

The following table describes the fields in the Input tab of the Lock activity:

Input Item Data Type Description
The following fields are the child fields of the LockOptions node.
lockWait Integer Indicates amount of time in milliseconds that a Lock operation waits for the lock to be cleared if the tuple has been locked. The value of the lockWait field overwrites the value in the Lock wait (milliseconds) field, which is specified in the Advanced tab of the Space shared resource.
Note: The default value of -2 or a null value indicates that the value set in the Lock wait (milliseconds) field is not overwritten.
isForget Boolean Specifies whether to return tuples in the Output tab. The value is true or false.
spaceResultHandlerKey String Indicates the key of the SpaceResultHandler activity, which is used for the asynchronous operation. The value of the spaceResultHandlerKey field overwrites the value in the Space Result Handler Key field, which is specified in the Advanced tab of the Lock activity.
Note: This field is displayed only when you select the Async Operation check box in the Configuration tab.
Closure Any of the following data types:
  • Boolean
  • Char
  • Short
  • Integer
  • Long
  • Float
  • Double
  • Blob
  • String
  • Datetime
Indicates the closed data transferred to the SpaceResultHandler activity during the asynchronous operation.

This field is displayed only when you select the Async Operation check box in the Configuration tab of the Lock activity.

Output

In the Output tab, you can find the operation results.

Note: If you select the Forget check box in the Advanced tab or set the value of the isForget field to true under the LockOptions node in the Input tab, no tuples are returned in the Output tab.

If you select the Async Operation check box in the Configuration tab, the Output tab is empty.

The following table describes the fields in the Output tab of the Lock activity:

Output Item Datatype Description
The ResultList node contains the following fields:
HasError Boolean Indicates whether the results have errors.
  • The value is true when one or more results have errors.
  • The value is false when no error occurs.
Result Any of the following data types:
  • Boolean
  • Char
  • Short
  • Integer
  • Long
  • Float
  • Double
  • Blob
  • String
  • Datetime
Indicates the results that contain the following items:
  • Status: the ActiveSpaces status code returned by TIBCO ActiveSpaces functions. See TIBCO ActiveSpaces Java API Reference for more information.
  • Tuple: This field lists tuples that have been locked in the associated space. A result can contain one tuple or none.
  • HasError: (Boolean value) The value of true indicates that an error is returned. The value of true indicates that no error is returned.
  • Error: The error returned by TIBCO ActiveSpaces during the tuple processing.

Fault

In the Fault tab, you can find the error code and error message of the Lock activity. See Error Codes for more detailed explanation of the errors.

The following table describes the errors in the Fault tab of the Lock activity:

Error Schema Element Datatype Description
msg String The TIBCO ActiveMatrix BusinessWorks Plug-in for ActiveSpaces error message.
msgCode String The TIBCO ActiveMatrix BusinessWorks Plug-in for ActiveSpaces error code.
ASStatus String The status code returned by TIBCO ActiveSpaces functions.

See TIBCO ActiveSpaces Java API Reference for more information.