add no locking feature

It provides an interface to applications for locking
purposes that always succeeds.  It does not deny
acquiring resource locks.

Issue-ID: POLICY-3114
Signed-off-by: jhh <jorge.hernandez-herrero@att.com>
Change-Id: I6aebb5f40e4176e0ff7b0e6c6d4042a79dd0b7a3
Signed-off-by: jhh <jorge.hernandez-herrero@att.com>

2 files changed, 97 insertions, 0 deletions

diff --git a/feature-no-locking/src/main/java/org/onap/policy/no/locking/NoLockManager.java b/feature-no-locking/src/main/java/org/onap/policy/no/locking/NoLockManager.java
new file mode 100644
index 00000000..1fa44391
--- /dev/null
+++ b/feature-no-locking/src/main/java/org/onap/policy/no/locking/NoLockManager.java
@@ -0,0 +1,96 @@
+/*
+ * ============LICENSE_START=======================================================
+ * ONAP
+ * ================================================================================
+ * Copyright (C) 2021 AT&T Intellectual Property. All rights reserved.
+ * ================================================================================
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ * ============LICENSE_END=========================================================
+ */
+
+package org.onap.policy.no.locking;
+
+import java.util.Properties;
+import lombok.NoArgsConstructor;
+import lombok.ToString;
+import org.onap.policy.drools.core.lock.AlwaysSuccessLock;
+import org.onap.policy.drools.core.lock.Lock;
+import org.onap.policy.drools.core.lock.LockCallback;
+import org.onap.policy.drools.core.lock.PolicyResourceLockManager;
+import org.onap.policy.drools.features.PolicyEngineFeatureApi;
+import org.onap.policy.drools.system.PolicyEngine;
+
+/**
+ * In contrast with other implementations the no-lock manager provides non-synchronized access
+ * to resources.
+ */
+
+@NoArgsConstructor
+@ToString
+public class NoLockManager implements PolicyResourceLockManager, PolicyEngineFeatureApi {
+
+    protected static final int SEQNO = 2000;
+
+    @Override
+    public Lock createLock(String resourceId, String ownerKey, int holdSec,
+            LockCallback callback, boolean waitForLock) {
+        AlwaysSuccessLock successLock =  new AlwaysSuccessLock(resourceId, ownerKey, holdSec, callback);
+        successLock.notifyAvailable();
+        return successLock;
+    }
+
+    @Override
+    public boolean lock() {
+        return true;
+    }
+
+    @Override
+    public boolean unlock() {
+        return true;
+    }
+
+    @Override
+    public boolean isLocked() {
+        return false;
+    }
+
+    @Override
+    public boolean start() {
+        return true;
+    }
+
+    @Override
+    public boolean stop() {
+        return true;
+    }
+
+    @Override
+    public void shutdown() {
+        // nothing to do
+    }
+
+    @Override
+    public boolean isAlive() {
+        return true;
+    }
+
+    @Override
+    public int getSequenceNumber() {
+        return SEQNO;
+    }
+
+    @Override
+    public PolicyResourceLockManager beforeCreateLockManager(PolicyEngine engine, Properties properties) {
+        return this;
+    }
+}
diff --git a/feature-no-locking/src/main/resources/META-INF.services/org.onap.policy.drools.features.PolicyEngineFeatureApi b/feature-no-locking/src/main/resources/META-INF.services/org.onap.policy.drools.features.PolicyEngineFeatureApi
new file mode 100644
index 00000000..e8a5d79f
--- /dev/null
+++ b/feature-no-locking/src/main/resources/META-INF.services/org.onap.policy.drools.features.PolicyEngineFeatureApi
@@ -0,0 +1 @@
+org.onap.policy.no.locking.NoLockManager
\ No newline at end of file