From d935985ec1b541558864f146c4dd530571f09df4 Mon Sep 17 00:00:00 2001
From: Ganesh <ganesh.pagade@gmail.com>
Date: Sun, 11 Feb 2018 13:29:30 +0530
Subject: [PATCH] Priorityjobscheduler (#3583)

* priority based job execution in java

* minor fixes

* updated to use java 8 features

* fix need for type inference

* handle exception

* indentation

* handling exception generated during terminal of normal flow

* handling exception generated during terminal of normal flow

* added comment
---
 .../concurrent/prioritytaskexecution/Job.java        |  3 ++-
 .../prioritytaskexecution/PriorityJobScheduler.java  | 12 ++++++------
 .../PriorityJobSchedulerUnitTest.java                |  4 +++-
 3 files changed, 11 insertions(+), 8 deletions(-)

diff --git a/core-java-concurrency/src/main/java/com/baeldung/concurrent/prioritytaskexecution/Job.java b/core-java-concurrency/src/main/java/com/baeldung/concurrent/prioritytaskexecution/Job.java
index a70041ed7d..9900d1c63d 100644
--- a/core-java-concurrency/src/main/java/com/baeldung/concurrent/prioritytaskexecution/Job.java
+++ b/core-java-concurrency/src/main/java/com/baeldung/concurrent/prioritytaskexecution/Job.java
@@ -16,7 +16,8 @@ public class Job implements Runnable {
     @Override
     public void run() {
         try {
-            System.out.println("Job:" + jobName + " Priority:" + jobPriority);
+            System.out.println("Job:" + jobName + 
+              " Priority:" + jobPriority);
             Thread.sleep(1000);
         } catch (InterruptedException ignored) {
         }
diff --git a/core-java-concurrency/src/main/java/com/baeldung/concurrent/prioritytaskexecution/PriorityJobScheduler.java b/core-java-concurrency/src/main/java/com/baeldung/concurrent/prioritytaskexecution/PriorityJobScheduler.java
index 70fd1710c0..ba55696d5a 100644
--- a/core-java-concurrency/src/main/java/com/baeldung/concurrent/prioritytaskexecution/PriorityJobScheduler.java
+++ b/core-java-concurrency/src/main/java/com/baeldung/concurrent/prioritytaskexecution/PriorityJobScheduler.java
@@ -9,21 +9,21 @@ import java.util.concurrent.TimeUnit;
 public class PriorityJobScheduler {
 
     private ExecutorService priorityJobPoolExecutor;
-    private ExecutorService priorityJobScheduler;
-    private PriorityBlockingQueue<Runnable> priorityQueue;
+    private ExecutorService priorityJobScheduler = 
+      Executors.newSingleThreadExecutor();
+    private PriorityBlockingQueue<Job> priorityQueue;
 
     public PriorityJobScheduler(Integer poolSize, Integer queueSize) {
         priorityJobPoolExecutor = Executors.newFixedThreadPool(poolSize);
-        Comparator<? super Job> jobComparator = Comparator.comparing(Job::getJobPriority);
-        priorityQueue = new PriorityBlockingQueue<Runnable>(queueSize, 
-          (Comparator<? super Runnable>) jobComparator);
+        priorityQueue = new PriorityBlockingQueue<Job>(queueSize, 
+          Comparator.comparing(Job::getJobPriority));
 
-        priorityJobScheduler = Executors.newSingleThreadExecutor();
         priorityJobScheduler.execute(()->{
             while (true) {
                 try {
                     priorityJobPoolExecutor.execute(priorityQueue.take());
                 } catch (InterruptedException e) {
+                    // exception needs special handling
                     break;
                 }
             }
diff --git a/core-java-concurrency/src/test/java/com/baeldung/concurrent/prioritytaskexecution/PriorityJobSchedulerUnitTest.java b/core-java-concurrency/src/test/java/com/baeldung/concurrent/prioritytaskexecution/PriorityJobSchedulerUnitTest.java
index 902bada3a2..1e67fe45c1 100644
--- a/core-java-concurrency/src/test/java/com/baeldung/concurrent/prioritytaskexecution/PriorityJobSchedulerUnitTest.java
+++ b/core-java-concurrency/src/test/java/com/baeldung/concurrent/prioritytaskexecution/PriorityJobSchedulerUnitTest.java
@@ -30,7 +30,9 @@ public class PriorityJobSchedulerUnitTest {
         // delay to avoid job sleep (added for demo) being interrupted
         try {
             Thread.sleep(2000);
-        } catch (InterruptedException ignored) {
+        } catch (InterruptedException e) {
+            Thread.currentThread().interrupt();
+            throw new RuntimeException(e);
         }
         
         pjs.closeScheduler();