+ remove unused internal class

spring-data-redis/src/main/java/org/springframework/data/keyvalue/redis/support/atomic/CASUtils.java

@@ -1,73 +0,0 @@
-/*
- * Copyright 2011 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.data.keyvalue.redis.support.atomic;
-
-import java.util.Collections;
-import java.util.concurrent.Callable;
-
-import org.springframework.data.keyvalue.redis.core.RedisOperations;
-import org.springframework.data.keyvalue.redis.core.SessionCallback;
-
-/**
- * Check-And-Set (CAS) utility. Performs the CAS loop until successful pattern using
- * Redis watch/exec operations. 
- * 
- * The given callback can contain one or multiple reads followed by a multi call
- * and one or multiple writes:
- * 
- * <pre>
- * return CASUtils.execute(ops, key, new Callable<Integer>() {
- *  @Override
- *  public Integer call() throws Exception {
- *    // check
- *    int value = get();
- *    // start MULTI
- *    ops.multi();
- *    // set
- *    ops.increment(key, 1);
- *    return value;
- *  }
- * });
- * </pre>
- * 
- * @author Costin Leau
- */
-abstract class CASUtils {
-
-	public static <T, K, V> T execute(final RedisOperations<K, V> ops, final K key, final Callable<T> callback) {
-		return ops.execute(new SessionCallback<T>() {
-			@SuppressWarnings("unchecked")
-			@Override
-			public T execute(RedisOperations operations) {
-				try {
-					for (;;) {
-						operations.watch(Collections.singleton(key));
-						T result = callback.call();
-						if (operations.exec() != null) {
-							return result;
-						}
-					}
-				} catch (Exception ex) {
-					// includes DataAccessException
-					if (ex instanceof RuntimeException) {
-						throw (RuntimeException) ex;
-					}
-					throw new RuntimeException("Callback threw exception", ex);
-				}
-			}
-		});
-	}
-}