Feature - setIfExists method added to RBucket, RBucketRx, RBucketReactive interfaces. #2817

redisson/src/main/java/org/redisson/RedissonBucket.java

@@ -175,7 +175,7 @@ public class RedissonBucket<V> extends RedissonExpirable implements RBucket<V> {
         if (value == null) {
             throw new IllegalArgumentException("Value can't be null");
         }
-        return commandExecutor.writeAsync(getName(), codec, RedisCommands.SETPXNX, getName(), encode(value), "PX", timeUnit.toMillis(timeToLive), "NX");
+        return commandExecutor.writeAsync(getName(), codec, RedisCommands.SET_BOOLEAN, getName(), encode(value), "PX", timeUnit.toMillis(timeToLive), "NX");
     }
 
     @Override
@@ -188,6 +188,41 @@ public class RedissonBucket<V> extends RedissonExpirable implements RBucket<V> {
         return get(trySetAsync(value));
     }
 
+    @Override
+    public boolean setIfExists(V value) {
+        return get(setIfExistsAsync(value));
+    }
+
+    @Override
+    public RFuture<Boolean> setIfExistsAsync(V value) {
+        if (value == null) {
+            return commandExecutor.evalWriteAsync(getName(), codec, RedisCommands.EVAL_BOOLEAN,
+                  "local currValue = redis.call('get', KEYS[1]); " +
+                        "if currValue ~= false then " +
+                            "redis.call('del', KEYS[1]); " +
+                            "return 1;" +
+                        "end;" +
+                        "return 0; ",
+                    Collections.singletonList(getName()));
+        }
+
+        return commandExecutor.writeAsync(getName(), codec, RedisCommands.SET_BOOLEAN, getName(), encode(value), "XX");
+    }
+
+    @Override
+    public boolean setIfExists(V value, long timeToLive, TimeUnit timeUnit) {
+        return get(setIfExistsAsync(value, timeToLive, timeUnit));
+    }
+
+    @Override
+    public RFuture<Boolean> setIfExistsAsync(V value, long timeToLive, TimeUnit timeUnit) {
+        if (value == null) {
+            throw new IllegalArgumentException("Value can't be null");
+        }
+
+        return commandExecutor.writeAsync(getName(), codec, RedisCommands.SET_BOOLEAN, getName(), encode(value), "PX", timeUnit.toMillis(timeToLive), "XX");
+    }
+
     @Override
     public RFuture<V> getAndSetAsync(V value, long timeToLive, TimeUnit timeUnit) {
         return commandExecutor.evalWriteAsync(getName(), codec, RedisCommands.EVAL_OBJECT,

redisson/src/main/java/org/redisson/api/RBucket.java

@@ -67,6 +67,26 @@ public interface RBucket<V> extends RExpirable, RBucketAsync<V> {
      */
     boolean trySet(V value, long timeToLive, TimeUnit timeUnit);
 
+    /**
+     * Sets value only if it's already exists.
+     *
+     * @param value - value to set
+     * @return {@code true} if successful, or {@code false} if
+     *         element wasn't set
+     */
+    boolean setIfExists(V value);
+
+    /**
+     * Sets value only if it's already exists.
+     *
+     * @param value - value to set
+     * @param timeToLive - time to live interval
+     * @param timeUnit - unit of time to live interval
+     * @return {@code true} if successful, or {@code false} if
+     *         element wasn't set
+     */
+    boolean setIfExists(V value, long timeToLive, TimeUnit timeUnit);
+
     /**
      * Atomically sets the value to the given updated value
      * only if serialized state of the current value equals 

redisson/src/main/java/org/redisson/api/RBucketAsync.java

@@ -67,6 +67,26 @@ public interface RBucketAsync<V> extends RExpirableAsync {
      */
     RFuture<Boolean> trySetAsync(V value, long timeToLive, TimeUnit timeUnit);
 
+    /**
+     * Sets value only if it's already exists.
+     *
+     * @param value - value to set
+     * @return {@code true} if successful, or {@code false} if
+     *         element wasn't set
+     */
+    RFuture<Boolean> setIfExistsAsync(V value);
+
+    /**
+     * Sets value only if it's already exists.
+     *
+     * @param value - value to set
+     * @param timeToLive - time to live interval
+     * @param timeUnit - unit of time to live interval
+     * @return {@code true} if successful, or {@code false} if
+     *         element wasn't set
+     */
+    RFuture<Boolean> setIfExistsAsync(V value, long timeToLive, TimeUnit timeUnit);
+
     /**
      * Atomically sets the value to the given updated value
      * only if serialized state of the current value equals 

redisson/src/main/java/org/redisson/api/RBucketReactive.java

@@ -15,10 +15,10 @@
  */
 package org.redisson.api;
 
-import java.util.concurrent.TimeUnit;
-
 import reactor.core.publisher.Mono;
 
+import java.util.concurrent.TimeUnit;
+
 
 /**
  * Reactive implementation of object holder. Max size of object is 512MB
@@ -56,6 +56,26 @@ public interface RBucketReactive<V> extends RExpirableReactive {
      */
     Mono<Boolean> trySet(V value, long timeToLive, TimeUnit timeUnit);
 
+    /**
+     * Sets value only if it's already exists.
+     *
+     * @param value - value to set
+     * @return {@code true} if successful, or {@code false} if
+     *         element wasn't set
+     */
+    Mono<Boolean> setIfExists(V value);
+
+    /**
+     * Sets value only if it's already exists.
+     *
+     * @param value - value to set
+     * @param timeToLive - time to live interval
+     * @param timeUnit - unit of time to live interval
+     * @return {@code true} if successful, or {@code false} if
+     *         element wasn't set
+     */
+    Mono<Boolean> setIfExists(V value, long timeToLive, TimeUnit timeUnit);
+
     /**
      * Atomically sets the value to the given updated value
      * only if serialized state of the current value equals 

redisson/src/main/java/org/redisson/api/RBucketRx.java

@@ -15,12 +15,12 @@
  */
 package org.redisson.api;
 
-import java.util.concurrent.TimeUnit;
-
 import io.reactivex.Completable;
 import io.reactivex.Maybe;
 import io.reactivex.Single;
 
+import java.util.concurrent.TimeUnit;
+
 
 /**
  * Reactive implementation of object holder. Max size of object is 512MB
@@ -58,6 +58,26 @@ public interface RBucketRx<V> extends RExpirableRx {
      */
     Single<Boolean> trySet(V value, long timeToLive, TimeUnit timeUnit);
 
+    /**
+     * Sets value only if it's already exists.
+     *
+     * @param value - value to set
+     * @return {@code true} if successful, or {@code false} if
+     *         element wasn't set
+     */
+    Single<Boolean> setIfExists(V value);
+
+    /**
+     * Sets value only if it's already exists.
+     *
+     * @param value - value to set
+     * @param timeToLive - time to live interval
+     * @param timeUnit - unit of time to live interval
+     * @return {@code true} if successful, or {@code false} if
+     *         element wasn't set
+     */
+    Single<Boolean> setIfExists(V value, long timeToLive, TimeUnit timeUnit);
+
     /**
      * Atomically sets the value to the given updated value
      * only if serialized state of the current value equals 

redisson/src/main/java/org/redisson/client/protocol/RedisCommands.java

@@ -299,7 +299,7 @@ public interface RedisCommands {
     RedisCommand<Object> GETSET = new RedisCommand<Object>("GETSET");
     RedisCommand<Void> SET = new RedisCommand<Void>("SET", new VoidReplayConvertor());
     RedisCommand<Void> APPEND = new RedisCommand<Void>("APPEND", new VoidReplayConvertor());
-    RedisCommand<Boolean> SETPXNX = new RedisCommand<Boolean>("SET", new BooleanNotNullReplayConvertor());
+    RedisCommand<Boolean> SET_BOOLEAN = new RedisCommand<Boolean>("SET", new BooleanNotNullReplayConvertor());
     RedisCommand<Boolean> SETNX = new RedisCommand<Boolean>("SETNX", new BooleanReplayConvertor());
     RedisCommand<Void> PSETEX = new RedisCommand<Void>("PSETEX", new VoidReplayConvertor());
 

redisson/src/test/java/org/redisson/RedissonBucketTest.java

@@ -216,6 +216,23 @@ public class RedissonBucketTest extends BaseTest {
         assertThat(r1.isExists()).isFalse();
     }
 
+    @Test
+    public void testSetIfExists() throws InterruptedException {
+        RBucket<String> r1 = redisson.getBucket("test1");
+        assertThat(r1.setIfExists("0")).isFalse();
+        assertThat(r1.isExists()).isFalse();
+        r1.set("1");
+        assertThat(r1.setIfExists("2")).isTrue();
+        assertThat(r1.get()).isEqualTo("2");
+
+        RBucket<String> r2 = redisson.getBucket("test2");
+        r2.set("1");
+        assertThat(r2.setIfExists("2", 1, TimeUnit.SECONDS)).isTrue();
+        assertThat(r2.get()).isEqualTo("2");
+        Thread.sleep(1000);
+        assertThat(r2.isExists()).isFalse();
+    }
+
     @Test
     public void testTrySet() {
         RBucket<String> r1 = redisson.getBucket("testTrySet");