DATAREDIS-872 - Polishing.

Create unit tests for RedisAtomic counter initialization. Refactor setIfAbsent(…) method to initializeIfAbsent() to not expose additional API methods.

Original pull request: #367.

src/main/java/org/springframework/data/redis/support/atomic/RedisAtomicDouble.java

@@ -91,7 +91,7 @@ public class RedisAtomicDouble extends Number implements Serializable, BoundKeyO
 		this.operations = generalOps.opsForValue();
 
 		if (initialValue == null) {
-			setIfAbsent(0);
+			initializeIfAbsent();
 		} else {
 			set(initialValue);
 		}
@@ -135,12 +135,16 @@ public class RedisAtomicDouble extends Number implements Serializable, BoundKeyO
 		this.operations = generalOps.opsForValue();
 
 		if (initialValue == null) {
-			setIfAbsent(0);
+			initializeIfAbsent();
 		} else {
 			set(initialValue);
 		}
 	}
 
+	private void initializeIfAbsent() {
+		operations.setIfAbsent(key, (double) 0);
+	}
+
 	/**
 	 * Get the current value.
 	 *
@@ -165,16 +169,6 @@ public class RedisAtomicDouble extends Number implements Serializable, BoundKeyO
 		operations.set(key, newValue);
 	}
 
-	/**
-	 * Sets to the given value, only if {@code key} does not exist.
-	 *
-	 * @param newValue the new value.
-	 * @return true if successful. False return indicates that {@code key} already existed.
-	 */
-	public Boolean setIfAbsent(double newValue) {
-		return operations.setIfAbsent(key, newValue);
-	}
-
 	/**
 	 * Set to the given value and return the old value.
 	 *

src/main/java/org/springframework/data/redis/support/atomic/RedisAtomicInteger.java

@@ -114,7 +114,7 @@ public class RedisAtomicInteger extends Number implements Serializable, BoundKey
 		this.operations = generalOps.opsForValue();
 
 		if (initialValue == null) {
-			setIfAbsent(0);
+			initializeIfAbsent();
 		} else {
 			set(initialValue);
 		}
@@ -133,12 +133,16 @@ public class RedisAtomicInteger extends Number implements Serializable, BoundKey
 		this.operations = generalOps.opsForValue();
 
 		if (initialValue == null) {
-			setIfAbsent(0);
+			initializeIfAbsent();
 		} else {
 			set(initialValue);
 		}
 	}
 
+	private void initializeIfAbsent() {
+		operations.setIfAbsent(key, 0);
+	}
+
 	/**
 	 * Get the current value.
 	 *
@@ -163,16 +167,6 @@ public class RedisAtomicInteger extends Number implements Serializable, BoundKey
 		operations.set(key, newValue);
 	}
 
-	/**
-	 * Sets to the given value, only if {@code key} does not exist.
-	 *
-	 * @param newValue the new value.
-	 * @return true if successful. False return indicates that {@code key} already existed.
-	 */
-	public Boolean setIfAbsent(int newValue) {
-		return operations.setIfAbsent(key, newValue);
-	}
-
 	/**
 	 * Set to the given value and return the old value.
 	 *

src/main/java/org/springframework/data/redis/support/atomic/RedisAtomicLong.java

@@ -92,7 +92,7 @@ public class RedisAtomicLong extends Number implements Serializable, BoundKeyOpe
 		this.operations = generalOps.opsForValue();
 
 		if (initialValue == null) {
-			setIfAbsent(0);
+			initializeIfAbsent();
 		} else {
 			set(initialValue);
 		}
@@ -140,12 +140,16 @@ public class RedisAtomicLong extends Number implements Serializable, BoundKeyOpe
 		this.operations = generalOps.opsForValue();
 
 		if (initialValue == null) {
-			setIfAbsent(0);
+			initializeIfAbsent();
 		} else {
 			set(initialValue);
 		}
 	}
 
+	private void initializeIfAbsent() {
+		operations.setIfAbsent(key, (long) 0);
+	}
+
 	/**
 	 * Get the current value.
 	 *
@@ -170,16 +174,6 @@ public class RedisAtomicLong extends Number implements Serializable, BoundKeyOpe
 		operations.set(key, newValue);
 	}
 
-	/**
-	 * Sets to the given value, only if {@code key} does not exist.
-	 *
-	 * @param newValue the new value.
-	 * @return true if successful. False return indicates that {@code key} already existed.
-	 */
-	public Boolean setIfAbsent(long newValue) {
-		return operations.setIfAbsent(key, newValue);
-	}
-
 	/**
 	 * Set to the given value and return the old value.
 	 *