graceful shutdown. #185

src/main/java/org/redisson/connection/MasterSlaveConnectionManager.java

@@ -46,6 +46,7 @@ import org.redisson.async.AsyncOperation;
 import org.redisson.async.SyncInterruptedOperation;
 import org.redisson.async.SyncOperation;
 import org.redisson.codec.RedisCodecWrapper;
+import org.redisson.misc.InfinitySemaphoreLatch;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -72,6 +73,8 @@ public class MasterSlaveConnectionManager implements ConnectionManager {
 
     private final HashedWheelTimer timer = new HashedWheelTimer();
 
+    private InfinitySemaphoreLatch latch = new InfinitySemaphoreLatch();
+
     protected RedisCodec codec;
 
     protected EventLoopGroup group;
@@ -124,6 +127,7 @@ public class MasterSlaveConnectionManager implements ConnectionManager {
 
     public <T> FutureListener<T> createReleaseWriteListener(final int slot,
                                     final RedisConnection conn, final Timeout timeout) {
+        latch.release();
         return new FutureListener<T>() {
             @Override
             public void operationComplete(io.netty.util.concurrent.Future<T> future) throws Exception {
@@ -135,6 +139,7 @@ public class MasterSlaveConnectionManager implements ConnectionManager {
 
     public <T> FutureListener<T> createReleaseReadListener(final int slot,
                                     final RedisConnection conn, final Timeout timeout) {
+        latch.release();
         return new FutureListener<T>() {
             @Override
             public void operationComplete(io.netty.util.concurrent.Future<T> future) throws Exception {
@@ -154,6 +159,11 @@ public class MasterSlaveConnectionManager implements ConnectionManager {
     }
 
     private <V, T> void writeAllAsync(final int slot, final AsyncOperation<V, T> asyncOperation, final AtomicInteger counter, final Promise<T> mainPromise, final int attempt) {
+        if (!latch.acquire()) {
+            mainPromise.setFailure(new IllegalStateException("Redisson is shutdown"));
+            return;
+        }
+
         final Promise<T> promise = getGroup().next().newPromise();
         final AtomicReference<RedisException> ex = new AtomicReference<RedisException>();
 
@@ -225,6 +235,11 @@ public class MasterSlaveConnectionManager implements ConnectionManager {
     }
 
     private <V, T> void writeAsync(final int slot, final AsyncOperation<V, T> asyncOperation, final Promise<T> mainPromise, final int attempt) {
+        if (!latch.acquire()) {
+            mainPromise.setFailure(new IllegalStateException("Redisson is shutdown"));
+            return;
+        }
+
         final Promise<T> promise = getGroup().next().newPromise();
         final AtomicReference<RedisException> ex = new AtomicReference<RedisException>();
 
@@ -290,6 +305,9 @@ public class MasterSlaveConnectionManager implements ConnectionManager {
     }
 
     private <V, R> R write(int slot, SyncInterruptedOperation<V, R> operation, int attempt) throws InterruptedException {
+        if (!latch.acquire()) {
+            return null;
+        }
         try {
             RedisConnection<Object, V> connection = connectionWriteOp(slot);
             try {
@@ -305,6 +323,7 @@ public class MasterSlaveConnectionManager implements ConnectionManager {
             } catch (InterruptedException e) {
                 throw e;
             } finally {
+                latch.release();
                 releaseWrite(slot, connection);
             }
         } catch (RedisConnectionException e) {
@@ -331,6 +350,9 @@ public class MasterSlaveConnectionManager implements ConnectionManager {
     }
 
     private <V, R> R write(int slot, SyncOperation<V, R> operation, int attempt) {
+        if (!latch.acquire()) {
+            return null;
+        }
         try {
             RedisConnection<Object, V> connection = connectionWriteOp(slot);
             try {
@@ -344,6 +366,7 @@ public class MasterSlaveConnectionManager implements ConnectionManager {
                 attempt++;
                 return write(slot, operation, attempt);
             } finally {
+                latch.release();
                 releaseWrite(slot, connection);
             }
         } catch (RedisConnectionException e) {
@@ -370,6 +393,10 @@ public class MasterSlaveConnectionManager implements ConnectionManager {
     }
 
     private <V, R> R read(int slot, SyncOperation<V, R> operation, int attempt) {
+        if (!latch.acquire()) {
+            return null;
+        }
+
         try {
             RedisConnection<Object, V> connection = connectionReadOp(slot);
             try {
@@ -383,6 +410,7 @@ public class MasterSlaveConnectionManager implements ConnectionManager {
                 attempt++;
                 return read(slot, operation, attempt);
             } finally {
+                latch.release();
                 releaseRead(slot, connection);
             }
         } catch (RedisConnectionException e) {
@@ -461,6 +489,11 @@ public class MasterSlaveConnectionManager implements ConnectionManager {
     }
 
     private <V, T> void readAsync(final int slot, final AsyncOperation<V, T> asyncOperation, final Promise<T> mainPromise, final int attempt) {
+        if (!latch.acquire()) {
+            mainPromise.setFailure(new IllegalStateException("Redisson is shutdown"));
+            return;
+        }
+
         final Promise<T> promise = getGroup().next().newPromise();
         final AtomicReference<RedisException> ex = new AtomicReference<RedisException>();
 
@@ -793,6 +826,7 @@ public class MasterSlaveConnectionManager implements ConnectionManager {
 
     @Override
     public void shutdown() {
+        latch.closeAndAwaitUninterruptibly();
         for (MasterSlaveEntry entry : entries.values()) {
             entry.shutdown();
         }

src/main/java/org/redisson/misc/InfinitySemaphoreLatch.java

@@ -0,0 +1,109 @@
+/**
+ * Copyright 2014 Nikita Koksharov, Nickolay Borbit
+ *
+ * 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.
+ */
+package org.redisson.misc;
+
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.atomic.AtomicInteger;
+import java.util.concurrent.locks.AbstractQueuedSynchronizer;
+
+/**
+ *
+ * Code parts from Manik Surtani (<a href="mailto:manik@jboss.org">manik@jboss.org</a>)
+ * @author Nikita Koksharov
+ */
+public class InfinitySemaphoreLatch extends AbstractQueuedSynchronizer {
+
+    private static final long serialVersionUID = 1744280161777661090l;
+
+    volatile boolean closed;
+    AtomicInteger sharedResources = new AtomicInteger();
+
+    // the following states are used in the AQS.
+    private static final int OPEN_STATE = 0;
+
+    public InfinitySemaphoreLatch() {
+        setState(OPEN_STATE);
+    }
+
+    @Override
+    public final int tryAcquireShared(int ignored) {
+        // return 1 if we allow the requestor to proceed, -1 if we want the
+        // requestor to block.
+        return getState() == OPEN_STATE ? 1 : -1;
+    }
+
+    @Override
+    public final boolean tryReleaseShared(int state) {
+        // used as a mechanism to set the state of the Sync.
+        setState(state);
+        return true;
+    }
+
+    public final boolean acquire() {
+        if (closed) {
+            return false;
+        }
+        releaseShared(sharedResources.incrementAndGet());
+        return true;
+    }
+
+    public final void release() {
+        // do not use setState() directly since this won't notify parked
+        // threads.
+        releaseShared(sharedResources.decrementAndGet());
+    }
+
+    public boolean isOpened() {
+        return getState() == OPEN_STATE;
+    }
+
+    // waiting for an open state
+    public final void closeAndAwaitUninterruptibly() {
+        closed = true;
+        try {
+            await();
+        } catch (InterruptedException e) {
+            Thread.currentThread().interrupt();
+        }
+    }
+
+    // waiting for an open state
+    public final void await() throws InterruptedException {
+        acquireSharedInterruptibly(1); // the 1 is a dummy value that is not
+                                       // used.
+    }
+
+    public final void awaitUninterruptibly() {
+        try {
+            await();
+        } catch (InterruptedException e) {
+            Thread.currentThread().interrupt();
+        }
+    }
+
+    public final boolean await(long time, TimeUnit unit) throws InterruptedException {
+        return tryAcquireSharedNanos(1, unit.toNanos(time)); // the 1 is a dummy
+                                                             // value that is
+                                                             // not used.
+    }
+
+    @Override
+    public String toString() {
+        int s = getState();
+        String q = hasQueuedThreads() ? "non" : "";
+        return "ReclosableLatch [State = " + s + ", " + q + "empty queue]";
+    }
+}

src/main/java/org/redisson/misc/ReclosableLatch.java

@@ -69,6 +69,7 @@ public class ReclosableLatch extends AbstractQueuedSynchronizer {
       return getState() == OPEN_STATE;
    }
 
+   // waiting for an open state
    public final void await() throws InterruptedException {
       acquireSharedInterruptibly(1); // the 1 is a dummy value that is not used.
    }