1 files changed, 25 insertions, 202 deletions
diff --git a/policy-core/src/main/java/org/onap/policy/drools/core/lock/PolicyResourceLockManager.java b/policy-core/src/main/java/org/onap/policy/drools/core/lock/PolicyResourceLockManager.java
index 0e73eac1..bbf7d229 100644
--- a/policy-core/src/main/java/org/onap/policy/drools/core/lock/PolicyResourceLockManager.java
+++ b/policy-core/src/main/java/org/onap/policy/drools/core/lock/PolicyResourceLockManager.java
@@ -20,213 +20,36 @@
 
 package org.onap.policy.drools.core.lock;
 
-import java.util.List;
-import java.util.function.Function;
-import java.util.function.Supplier;
-import org.onap.policy.drools.core.lock.PolicyResourceLockFeatureApi.OperResult;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
+import org.onap.policy.common.capabilities.Lockable;
+import org.onap.policy.common.capabilities.Startable;
 
 /**
- * Manager of resource locks. Checks for API implementers.
+ * Manager of resource locks.
  */
-public class PolicyResourceLockManager extends SimpleLockManager {
-
-    private static Logger logger = LoggerFactory.getLogger(PolicyResourceLockManager.class);
-
-    /**
-     * Used by junit tests.
-     */
-    protected PolicyResourceLockManager() {
-        super();
-    }
-
-    /**
-     * Get instance.
-     *
-     * @return the manager singleton
-     */
-    public static PolicyResourceLockManager getInstance() {
-        return Singleton.instance;
-    }
-
-    @Override
-    public boolean lock(String resourceId, String owner, int holdSec) {
-        if (resourceId == null) {
-            throw makeNullArgException(MSG_NULL_RESOURCE_ID);
-        }
-
-        if (owner == null) {
-            throw makeNullArgException(MSG_NULL_OWNER);
-        }
-
-
-        return doBoolIntercept(impl -> impl.beforeLock(resourceId, owner, holdSec), () -> {
-
-            // implementer didn't do the work - defer to the superclass
-            boolean locked = super.lock(resourceId, owner, holdSec);
-
-            doIntercept(false, impl -> impl.afterLock(resourceId, owner, locked));
-
-            return locked;
-        });
-    }
-
-    @Override
-    public boolean refresh(String resourceId, String owner, int holdSec) {
-        if (resourceId == null) {
-            throw makeNullArgException(MSG_NULL_RESOURCE_ID);
-        }
-
-        if (owner == null) {
-            throw makeNullArgException(MSG_NULL_OWNER);
-        }
-
-
-        return doBoolIntercept(impl -> impl.beforeRefresh(resourceId, owner, holdSec), () -> {
-
-            // implementer didn't do the work - defer to the superclass
-            boolean refreshed = super.refresh(resourceId, owner, holdSec);
-
-            doIntercept(false, impl -> impl.afterRefresh(resourceId, owner, refreshed));
-
-            return refreshed;
-        });
-    }
-
-    @Override
-    public boolean unlock(String resourceId, String owner) {
-        if (resourceId == null) {
-            throw makeNullArgException(MSG_NULL_RESOURCE_ID);
-        }
-
-        if (owner == null) {
-            throw makeNullArgException(MSG_NULL_OWNER);
-        }
-
-
-        return doBoolIntercept(impl -> impl.beforeUnlock(resourceId, owner), () -> {
-
-            // implementer didn't do the work - defer to the superclass
-            boolean unlocked = super.unlock(resourceId, owner);
-
-            doIntercept(false, impl -> impl.afterUnlock(resourceId, owner, unlocked));
-
-            return unlocked;
-        });
-    }
-
-    /**
-     * Is locked.
-     *
-     * @throws IllegalArgumentException if the resourceId is {@code null}
-     */
-    @Override
-    public boolean isLocked(String resourceId) {
-        if (resourceId == null) {
-            throw makeNullArgException(MSG_NULL_RESOURCE_ID);
-        }
-
-
-        return doBoolIntercept(impl -> impl.beforeIsLocked(resourceId), () ->
-
-           // implementer didn't do the work - defer to the superclass
-           super.isLocked(resourceId)
-        );
-    }
+public interface PolicyResourceLockManager extends Startable, Lockable {
 
     /**
-     *  Is locked by.
+     * Requests a lock on a resource. Typically, the lock is not immediately granted,
+     * though a "lock" object is always returned. Once the lock has been granted (or
+     * denied), the callback will be invoked to indicate the result.
      *
-     * @throws IllegalArgumentException if the resourceId or owner is {@code null}
-     */
-    @Override
-    public boolean isLockedBy(String resourceId, String owner) {
-        if (resourceId == null) {
-            throw makeNullArgException(MSG_NULL_RESOURCE_ID);
-        }
-
-        if (owner == null) {
-            throw makeNullArgException(MSG_NULL_OWNER);
-        }
-
-        return doBoolIntercept(impl -> impl.beforeIsLockedBy(resourceId, owner), () ->
-
-            // implementer didn't do the work - defer to the superclass
-            super.isLockedBy(resourceId, owner)
-        );
-    }
-
-    /**
-     * Applies a function to each implementer of the lock feature. Returns as soon as one
-     * of them returns a result other than <b>OPER_UNHANDLED</b>. If they all return
-     * <b>OPER_UNHANDLED</b>, then it returns the result of applying the default function.
+     * <p/>
+     * Notes:
+     * <dl>
+     * <li>The callback may be invoked <i>before</i> this method returns</li>
+     * <li>The implementation need not honor waitForLock={@code true}</li>
+     * </dl>
      *
-     * @param interceptFunc intercept function
-     * @param defaultFunc default function
-     * @return {@code true} if success, {@code false} otherwise
-     */
-    private boolean doBoolIntercept(Function<PolicyResourceLockFeatureApi, OperResult> interceptFunc,
-                    Supplier<Boolean> defaultFunc) {
-
-        OperResult result = doIntercept(OperResult.OPER_UNHANDLED, interceptFunc);
-        if (result != OperResult.OPER_UNHANDLED) {
-            return (result == OperResult.OPER_ACCEPTED);
-        }
-
-        return defaultFunc.get();
-    }
-
-    /**
-     * Applies a function to each implementer of the lock feature. Returns as soon as one
-     * of them returns a non-null value.
-     *
-     * @param continueValue if the implementer returns this value, then it continues to
-     *        check addition implementers
-     * @param func function to be applied to the implementers
-     * @return first non-null value returned by an implementer, <i>continueValue</i> if
-     *       they all returned <i>continueValue</i>
-     */
-    private <T> T doIntercept(T continueValue, Function<PolicyResourceLockFeatureApi, T> func) {
-
-        for (PolicyResourceLockFeatureApi impl : getImplementers()) {
-            try {
-                T result = func.apply(impl);
-                if (result != continueValue) {
-                    return result;
-                }
-
-            } catch (RuntimeException e) {
-                logger.warn("lock feature {} threw an exception", impl, e);
-            }
-        }
-
-        return continueValue;
-    }
-
-    // these may be overridden by junit tests
-
-    /**
-     * Get implementers.
-     *
-     * @return the list of feature implementers
-     */
-    protected List<PolicyResourceLockFeatureApi> getImplementers() {
-        return PolicyResourceLockFeatureApiConstants.getImpl().getList();
-    }
-
-    /**
-     * Initialization-on-demand holder idiom.
-     */
-    private static class Singleton {
-
-        private static final PolicyResourceLockManager instance = new PolicyResourceLockManager();
-
-        /**
-         * Not invoked.
-         */
-        private Singleton() {
-            super();
-        }
-    }
+     * @param resourceId identifier of the resource to be locked
+     * @param ownerKey information identifying the owner requesting the lock
+     * @param holdSec amount of time, in seconds, for which the lock should be held once
+     *        it has been granted, after which it will automatically be released
+     * @param callback callback to be invoked once the lock is granted, or subsequently
+     *        lost; must not be {@code null}
+     * @param waitForLock {@code true} to wait for the lock, if it is currently locked,
+     *        {@code false} otherwise
+     * @return a new lock
+     */
+    public Lock createLock(String resourceId, String ownerKey, int holdSec, LockCallback callback,
+                    boolean waitForLock);
 }