The lock facility allows resource adaptors to obtain transaction-based distributed locks.

In order to use the lock facility, one must obtain:

  • a reference to the LockFacility itself; and

  • a reference to the SLEE Transaction Manager, as all locks must be obtained from within a transaction.

The following code fragment illustrates how you can obtain these references in a resource adaptor:

package ...

import javax.slee.resource.ConfigProperties;
import javax.slee.resource.ResourceAdaptor;
import javax.slee.resource.ResourceAdaptorContext;
import javax.slee.transaction.SleeTransactionManager;
import com.opencloud.rhino.facilities.lock.LockFacility;

public class FooResourceAdaptor implements ResourceAdaptor {
    public void setResourceAdaptorContext(ResourceAdaptorContext context) {
        // save context ref
        this.context = context;

        // ...

    public void raConfigure(ConfigProperties configProps) {
        // get refs to transaction manager and lock facility
        txManager = context.getSleeTransactionManager();
        lockFacility = (LockFacility)configProps.getProperty(LockFacility.CONFIG_PROPERTY_NAME).getValue();

        // ...

    // ...

    private ResourceAdaptorContext context;
    private SleeTransactionManager txManager;
    private LockFacility lockFacility;

With these references, one can then proceed to acquire locks as necessary. For example:

private void doSomeWorkThatRequiresALock() {
    // start a transaction
    SleeTransaction tx = txManager.beginSleeTransaction();
    try {
        // acquire exclusive lock

        // do the work
        // ...

        // successfully completed work - commit transaction
        // automatically causes the lock to be released
        tx = null;
    catch (Exception e) {
        if (tx != null) {
            // failed to complete work - rollback transaction
            // automatically causes the lock to be released
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