Configurable back off for listener recovery

Prior to this commit, DefaultMessageListenerContainer was recovering on failure using a fixed time interval, potentially in an infinite way. This commit adds an extra "backoff" property to the container that permits to fine tune the recovery interval using a BackOff instance. FixedBackOff provides a fixed interval between two attempts and a maximum number of retries. ExponentialBackOff increases an initial interval until a maximum interval has been reached. A BackOff instance can return a special "STOP" time value that indicates that no further attemps should be made. DefaultMessageListenerContainer uses this value to stop the container. protected method "sleepInbetweenRecoveryAttempts" has been renamed to "applyBackOff" and now returns a boolean that indicate if the back off has been applied and a new attempt should now be made. Issue: SPR-11746
2014-05-09 10:17:32 +02:00
parent 97fb308b6b
commit 6a0483128a
11 changed files with 804 additions and 18 deletions
--- a/spring-core/src/test/java/org/springframework/util/ExponentialBackOffTests.java
+++ b/spring-core/src/test/java/org/springframework/util/ExponentialBackOffTests.java
@@ -0,0 +1,124 @@
+/*
+ * Copyright 2002-2014 the original author or authors.
+ *
+ * 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.springframework.util;
+
+import static org.junit.Assert.assertEquals;
+
+import org.junit.Rule;
+import org.junit.Test;
+import org.junit.rules.ExpectedException;
+
+/**
+ *
+ * @author Stephane Nicoll
+ */
+public class ExponentialBackOffTests {
+
+	@Rule
+	public final ExpectedException thrown = ExpectedException.none();
+
+	@Test
+	public void defaultInstance() {
+		ExponentialBackOff backOff = new ExponentialBackOff();
+		assertEquals(2000l, backOff.nextBackOff());
+		assertEquals(3000l, backOff.nextBackOff());
+		assertEquals(4500l, backOff.nextBackOff());
+	}
+
+	@Test
+	public void simpleIncrease() {
+		ExponentialBackOff backOff = new ExponentialBackOff(100L, 2.0);
+		assertEquals(100l, backOff.nextBackOff());
+		assertEquals(200l, backOff.nextBackOff());
+		assertEquals(400l, backOff.nextBackOff());
+		assertEquals(800l, backOff.nextBackOff());
+	}
+
+	@Test
+	public void fixedIncrease() {
+		ExponentialBackOff backOff = new ExponentialBackOff(100L, 1.0);
+		backOff.setMaxElapsedTime(300l);
+		assertEquals(100l, backOff.nextBackOff());
+		assertEquals(100l, backOff.nextBackOff());
+		assertEquals(100l, backOff.nextBackOff());
+		assertEquals(BackOff.STOP, backOff.nextBackOff());
+	}
+
+	@Test
+	public void maxIntervalReached() {
+		ExponentialBackOff backOff = new ExponentialBackOff(2000L, 2.0);
+		backOff.setMaxInterval(4000L);
+		assertEquals(2000l, backOff.nextBackOff());
+		assertEquals(4000l, backOff.nextBackOff());
+		assertEquals(4000l, backOff.nextBackOff()); // max reached
+		assertEquals(4000l, backOff.nextBackOff());
+	}
+
+	@Test
+	public void maxAttemptsReached() {
+		ExponentialBackOff backOff = new ExponentialBackOff(2000L, 2.0);
+		backOff.setMaxElapsedTime(4000L);
+		assertEquals(2000l, backOff.nextBackOff());
+		assertEquals(4000l, backOff.nextBackOff());
+		assertEquals(BackOff.STOP, backOff.nextBackOff()); // > 4 sec wait in total
+	}
+
+	@Test
+	public void resetInstance() {
+		ExponentialBackOff backOff = new ExponentialBackOff();
+		backOff.setInitialInterval(2000L);
+		backOff.setMultiplier(2.0);
+		backOff.setMaxElapsedTime(4000L);
+		assertEquals(2000l, backOff.nextBackOff());
+		assertEquals(4000l, backOff.nextBackOff());
+		assertEquals(BackOff.STOP, backOff.nextBackOff());
+
+		backOff.reset();
+
+		assertEquals(2000l, backOff.nextBackOff());
+		assertEquals(4000l, backOff.nextBackOff());
+		assertEquals(BackOff.STOP, backOff.nextBackOff());
+	}
+
+	@Test
+	public void invalidInterval() {
+		ExponentialBackOff backOff = new ExponentialBackOff();
+
+		thrown.expect(IllegalArgumentException.class);
+		backOff.setMultiplier(0.9);
+	}
+
+	@Test
+	public void maxIntervalReachedImmediately() {
+		ExponentialBackOff backOff = new ExponentialBackOff(1000L, 2.0);
+		backOff.setMaxInterval(50L);
+
+		assertEquals(50L, backOff.nextBackOff());
+		assertEquals(50L, backOff.nextBackOff());
+	}
+
+	@Test
+	public void toStringContent() {
+		ExponentialBackOff backOff = new ExponentialBackOff(2000L, 2.0);
+		assertEquals("ExponentialBackOff{currentInterval=n/a, multiplier=2.0}", backOff.toString());
+		backOff.nextBackOff();
+		assertEquals("ExponentialBackOff{currentInterval=2000ms, multiplier=2.0}", backOff.toString());
+		backOff.nextBackOff();
+		assertEquals("ExponentialBackOff{currentInterval=4000ms, multiplier=2.0}", backOff.toString());
+	}
+
+}
--- a/spring-core/src/test/java/org/springframework/util/FixedBackOffTests.java
+++ b/spring-core/src/test/java/org/springframework/util/FixedBackOffTests.java
@@ -0,0 +1,84 @@
+/*
+ * Copyright 2002-2014 the original author or authors.
+ *
+ * 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.springframework.util;
+
+import static org.junit.Assert.*;
+
+import org.junit.Test;
+
+/**
+ * @author Stephane Nicoll
+ */
+public class FixedBackOffTests {
+
+	@Test
+	public void defaultInstance() {
+		FixedBackOff backOff = new FixedBackOff();
+		for (int i = 0; i < 100; i++) {
+			assertEquals(FixedBackOff.DEFAULT_INTERVAL, backOff.nextBackOff());
+		}
+	}
+
+	@Test
+	public void noAttemptAtAll() {
+		FixedBackOff backOff = new FixedBackOff(100L, 0L);
+		assertEquals(BackOff.STOP, backOff.nextBackOff());
+	}
+
+	@Test
+	public void maxAttemptsReached() {
+		FixedBackOff backOff = new FixedBackOff(200L, 2);
+		assertEquals(200l, backOff.nextBackOff());
+		assertEquals(200l, backOff.nextBackOff());
+		assertEquals(BackOff.STOP, backOff.nextBackOff());
+	}
+
+	@Test
+	public void resetOnInstance() {
+		FixedBackOff backOff = new FixedBackOff(100L, 1);
+		assertEquals(100l, backOff.nextBackOff());
+		assertEquals(BackOff.STOP, backOff.nextBackOff());
+
+		backOff.reset();
+
+		assertEquals(100l, backOff.nextBackOff());
+		assertEquals(BackOff.STOP, backOff.nextBackOff());
+	}
+
+	@Test
+	public void liveUpdate() {
+		FixedBackOff backOff = new FixedBackOff(100L, 1);
+		assertEquals(100l, backOff.nextBackOff());
+
+		backOff.setInterval(200l);
+		backOff.setMaxAttempts(2);
+
+		assertEquals(200l, backOff.nextBackOff());
+		assertEquals(BackOff.STOP, backOff.nextBackOff());
+	}
+
+	@Test
+	public void toStringContent() {
+		FixedBackOff backOff = new FixedBackOff(200L, 10);
+		assertEquals("FixedBackOff{interval=200, currentAttempts=0, maxAttempts=10}", backOff.toString());
+		backOff.nextBackOff();
+		assertEquals("FixedBackOff{interval=200, currentAttempts=1, maxAttempts=10}", backOff.toString());
+		backOff.nextBackOff();
+		assertEquals("FixedBackOff{interval=200, currentAttempts=2, maxAttempts=10}", backOff.toString());
+	}
+
+}