BackOff abstraction lives in util.backoff subpackage now

Issue: SPR-11746

spring-core/src/main/java/org/springframework/util/backoff/BackOff.java

@@ -14,7 +14,7 @@
  * limitations under the License.
  */
 
-package org.springframework.util;
+package org.springframework.util.backoff;
 
 /**
  * Provide a {@link BackOffExecution} that indicates the rate at which
@@ -23,23 +23,21 @@ package org.springframework.util;
  * <p>Users of this interface are expected to use it like this:
  *
  * <pre class="code">
- * {@code
+ * BackOffExecution exec = backOff.start();
  *
- *  BackOffExecution exec = backOff.start();
- *
- *  // In the operation recovery/retry loop:
- *  long waitInterval = exec.nextBackOffMillis();
- *  if (waitInterval == BackOffExecution.STOP) {
- *    // do not retry operation
- *  }
- *  else {
- *    // sleep, e.g. Thread.sleep(waitInterval)
- *    // retry operation
- *  }
+ * // In the operation recovery/retry loop:
+ * long waitInterval = exec.nextBackOffMillis();
+ * if (waitInterval == BackOffExecution.STOP) {
+ *     // do not retry operation
+ * }
+ * else {
+ *     // sleep, e.g. Thread.sleep(waitInterval)
+ *     // retry operation
+ * }
  * }</pre>
  *
- * Once the underlying operation has completed successfully, the execution
- * instance can be simply discarded.
+ * Once the underlying operation has completed successfully,
+ * the execution instance can be simply discarded.
  *
  * @author Stephane Nicoll
  * @since 4.1

spring-core/src/main/java/org/springframework/util/backoff/BackOffExecution.java

@@ -14,7 +14,7 @@
  * limitations under the License.
  */
 
-package org.springframework.util;
+package org.springframework.util.backoff;
 
 /**
  * Represent a particular back-off execution.
@@ -23,7 +23,7 @@ package org.springframework.util;
  *
  * @author Stephane Nicoll
  * @since 4.1
- * @see org.springframework.util.BackOff
+ * @see BackOff
  */
 public interface BackOffExecution {
 

spring-core/src/main/java/org/springframework/util/backoff/ExponentialBackOff.java

@@ -14,7 +14,7 @@
  * limitations under the License.
  */
 
-package org.springframework.util;
+package org.springframework.util.backoff;
 
 /**
  * Implementation of {@link BackOff} that increases the back off period for each
@@ -184,7 +184,7 @@ public class ExponentialBackOff implements BackOff {
 		@Override
 		public long nextBackOff() {
 			if (currentElapsedTime >= maxElapsedTime) {
-				return BackOffExecution.STOP;
+				return STOP;
 			}
 
 			long nextInterval = computeNextInterval();

spring-core/src/main/java/org/springframework/util/backoff/FixedBackOff.java

@@ -14,7 +14,7 @@
  * limitations under the License.
  */
 
-package org.springframework.util;
+package org.springframework.util.backoff;
 
 /**
  * A simple {@link BackOff} implementation that provides a fixed interval
@@ -102,7 +102,7 @@ public class FixedBackOff implements BackOff {
 				return getInterval();
 			}
 			else {
-				return BackOffExecution.STOP;
+				return STOP;
 			}
 		}
 

spring-core/src/main/java/org/springframework/util/backoff/package-info.java

@@ -0,0 +1,8 @@
+
+/**
+ *
+ * A generic back-off abstraction.
+ *
+ */
+package org.springframework.util.backoff;
+