Updated readme file

README.md

@@ -13,20 +13,22 @@
 
 ## Features
 
-* A message can be delayed for an arbitrary period or delivered immediately.
-* Multiple messages can be consumed in parallel by different workers.
-* Message delivery: It's guaranteed that a message is consumed **at least once**.  (Message would be consumed by a worker more than once due to the failure in the underlying worker/restart-process etc, otherwise exactly one delivery)
-* Support Redis cluster
-* Queue metrics
-* Different Redis connection for application and worker
-* Web interface for queue management and queue statistics
-* Automatic message serialization and deserialization
-* Queue concurrency
-* Group level queue priority(weighted and strict)
-* Sub queue priority(weighted and strict)
-* Task execution back off, exponential and fixed back off (default fixed back off)
-* Callbacks for different actions
-* Events 1. Bootstrap event 2. Task execution event.
+* **Message Scheduling** : A message can be scheduled for any arbitrary period
+* **Competing Consumers** multiple messages can be consumed in parallel by different workers.
+* **Message delivery**: It's guaranteed that a message is consumed **at least once**.  (Message would be consumed by a worker more than once due to the failure in the underlying worker/restart-process etc, otherwise exactly one delivery)
+* **Redis cluster** : Redis cluster can be used with driver.
+* **Metrics** : In flight messages, waiting for consumption and delayed messages
+* **Web interface**:  a web interface to manage a queue and queue insights including latency
+* **Automatic message serialization and deserialization**
+* **Concurrency**: Concurrency of any queue can be configured
+* **Queue Priority** :
+    * Group level queue priority(weighted and strict)
+    * Sub queue priority(weighted and strict)
+* **Execution Backoff** : Exponential and fixed back off (default fixed back off)
+* **Callbacks** : Callbacks for dead letter queue, discard etc
+* **Events** 1. Bootstrap event 2. Task execution event.
+* **Unique message** : Unique message processing for a queue based on the message id
+* Separate Redis connection for Rqueue
 
 ## Getting Started
 

rqueue-core/src/main/java/com/github/sonus21/rqueue/exception/LockCanNotBeAcquired.java

@@ -16,6 +16,10 @@
 
 package com.github.sonus21.rqueue.exception;
 
+/**
+ * Whenever a Redis lock can not be acuired due to some other is holding lock then this error would
+ * be thrown. The application should retry once this error occurs.
+ */
 public class LockCanNotBeAcquired extends RuntimeException {
 
   private static final long serialVersionUID = 598739372785907190L;

rqueue-core/src/main/java/com/github/sonus21/rqueue/listener/RqueueExecutor.java

@@ -172,7 +172,7 @@ void start() {
     long maxProcessingTime = getMaxProcessingTime();
     long startTime = System.currentTimeMillis();
     int retryCount = getRetryCount();
-    int attempt = 0;
+    int attempt = 1;
     ExecutionStatus status;
     try {
       do {