Merge pull request #549 from HeartSaVioR/make_multi_in_pipeline_and_sync_work_smoothly

Fix multi in Pipeline and sync() - JedisDataException (fixes #547)

src/main/java/redis/clients/jedis/Pipeline.java

@@ -31,6 +31,12 @@ public class Pipeline extends MultiKeyPipelineBase {
 	    return values;
 	}
 
+	public void setResponseDependency(Response<?> dependency) {
+	    for (Response<?> response : responses) {
+		response.setDependency(dependency);
+	    }
+	}
+
 	public void addResponse(Response<?> response) {
 	    responses.add(response);
 	}
@@ -106,6 +112,7 @@ public class Pipeline extends MultiKeyPipelineBase {
     public Response<List<Object>> exec() {
 	client.exec();
 	Response<List<Object>> response = super.getResponse(currentMulti);
+	currentMulti.setResponseDependency(response);
 	currentMulti = null;
 	return response;
     }

src/main/java/redis/clients/jedis/Response.java

@@ -8,6 +8,8 @@ public class Response<T> {
     private boolean set = false;
     private Builder<T> builder;
     private Object data;
+    private Response<?> dependency = null;
+    private boolean requestDependencyBuild = false;
 
     public Response(Builder<T> b) {
 	this.builder = b;
@@ -19,22 +21,38 @@ public class Response<T> {
     }
 
     public T get() {
+	// if response has dependency response and dependency is not built,
+	// build it first and no more!!
+	if (!requestDependencyBuild && dependency != null && dependency.set
+		&& !dependency.built) {
+	    requestDependencyBuild = true;
+	    dependency.build();
+	}
 	if (!set) {
 	    throw new JedisDataException(
 		    "Please close pipeline or multi block before calling this method.");
 	}
 	if (!built) {
+	    build();
+	}
+	return response;
+    }
+
+    public void setDependency(Response<?> dependency) {
+	this.dependency = dependency;
+	this.requestDependencyBuild = false;
+    }
+
+    private void build() {
 	if (data != null) {
 	    if (data instanceof JedisDataException) {
 		throw new JedisDataException((JedisDataException) data);
 	    }
 	    response = builder.build(data);
 	}
-	    this.data = null;
+	data = null;
 	built = true;
     }
-	return response;
-    }
 
     public String toString() {
 	return "Response " + builder.toString();

src/test/java/redis/clients/jedis/tests/PipeliningTest.java

@@ -251,6 +251,27 @@ public class PipeliningTest extends Assert {
 
     }
 
+    @Test
+    public void multiWithSync() {
+	jedis.set("foo", "314");
+	jedis.set("bar", "foo");
+	jedis.set("hello", "world");
+	Pipeline p = jedis.pipelined();
+	Response<String> r1 = p.get("bar");
+	p.multi();
+	Response<String> r2 = p.get("foo");
+	p.exec();
+	Response<String> r3 = p.get("hello");
+	p.sync();
+	
+	// before multi
+	assertEquals("foo", r1.get());
+	// It should be readable whether exec's response was built or not
+	assertEquals("314", r2.get());
+	// after multi
+	assertEquals("world", r3.get());
+    }
+
     @Test
     public void testDiscardInPipeline() {
 	Pipeline pipeline = jedis.pipelined();