[Scheduler Pattern] (Fix) check style problems

scheduler/src/main/java/com/iluwatar/scheduler/FirstComeFirstServedScheduler.java

@@ -5,6 +5,7 @@
 import java.util.LinkedList;
 import java.util.Queue;
 
+/**Tasks are scheduled in the order they arrive. */
 public class FirstComeFirstServedScheduler implements TaskScheduler, PropertyChangeListener {
   private final Queue<Task> taskQueue = new LinkedList<>();
 
@@ -17,7 +18,9 @@ public void scheduleTask(Task task) {
   @Override
   public void update(int deltaTime) {
     Task task = taskQueue.peek();
-    if (task == null) return;
+    if (task == null) {
+      return;
+    }
     task.execute(deltaTime);
   }
 

scheduler/src/main/java/com/iluwatar/scheduler/PriorityScheduler.java

@@ -5,12 +5,14 @@
 import java.util.PriorityQueue;
 import java.util.Queue;
 
+/** Tasks with higher priority values are executed before tasks with lower priority values. */
 public class PriorityScheduler implements TaskScheduler, PropertyChangeListener {
   private final Queue<Task> taskQueue =
       new PriorityQueue<>(
           (task1, task2) -> {
-            if (task2.getPriority() != task1.getPriority())
+            if (task2.getPriority() != task1.getPriority()) {
               return task2.getPriority() - task1.getPriority();
+            }
             return task1.getId() - task2.getId(); // lower id (earlier task) has higher priority
           });
 
@@ -23,7 +25,9 @@ public void scheduleTask(Task task) {
   @Override
   public void update(int deltaTime) {
     Task task = taskQueue.peek();
-    if (task == null) return;
+    if (task == null) {
+      return;
+    }
     task.execute(deltaTime);
   }
 

scheduler/src/main/java/com/iluwatar/scheduler/RoundRobinScheduler.java

@@ -3,6 +3,10 @@
 import java.util.LinkedList;
 import java.util.Queue;
 
+/**
+ * Round Robin technique. Tasks are executed in a cyclic order, with each task getting a fixed time
+ * quantum for execution.
+ */
 public class RoundRobinScheduler implements TaskScheduler {
   private final Queue<Task> taskQueue = new LinkedList<>();
 
@@ -14,8 +18,12 @@ public void scheduleTask(Task task) {
   @Override
   public void update(int deltaTime) {
     Task task = taskQueue.poll();
-    if (task == null) return;
+    if (task == null) {
+      return;
+    }
     task.execute(deltaTime);
-    if (!task.isComplete()) taskQueue.add(task);
+    if (!task.isComplete()) {
+      taskQueue.add(task);
+    }
   }
 }

scheduler/src/main/java/com/iluwatar/scheduler/ShortestRemainingTimeFirstScheduler.java

@@ -1,15 +1,16 @@
 package com.iluwatar.scheduler;
 
-import java.util.Comparator;
 import java.util.PriorityQueue;
 import java.util.Queue;
 
+/** The task with the shortest remaining execution time is given priority. */
 public class ShortestRemainingTimeFirstScheduler implements TaskScheduler {
   private final Queue<Task> taskQueue =
       new PriorityQueue<>(
           (task1, task2) -> {
-            if (task2.getRemainingTime() != task1.getRemainingTime())
+            if (task2.getRemainingTime() != task1.getRemainingTime()) {
               return task1.getRemainingTime() - task2.getRemainingTime();
+            }
             return task1.getId() - task2.getId(); // lower id (earlier task) has higher priority
           });
 
@@ -21,8 +22,12 @@ public void scheduleTask(Task task) {
   @Override
   public void update(int deltaTime) {
     Task task = taskQueue.poll();
-    if (task == null) return;
+    if (task == null) {
+      return;
+    }
     task.execute(deltaTime);
-    if (!task.isComplete()) taskQueue.add(task);
+    if (!task.isComplete()) {
+      taskQueue.add(task);
+    }
   }
 }

scheduler/src/main/java/com/iluwatar/scheduler/Simulator.java

@@ -20,6 +20,10 @@ public class Simulator implements PropertyChangeListener {
   private final LinkedHashMap<Integer, Integer> taskCompletedOrder = new LinkedHashMap<>();
   private int elapsedTime = 0;
 
+  /**
+   * Simulate scheduler schedule tasks, then return a LinkedHashMap present the completed order of
+   * tasks, which map task id to the time it completed.
+   */
   public LinkedHashMap<Integer, Integer> simulate() {
     while (elapsedTime < simulateTime) {
       if (tasks.containsKey(elapsedTime)) {

scheduler/src/main/java/com/iluwatar/scheduler/Task.java

@@ -4,6 +4,7 @@
 import lombok.Getter;
 import lombok.RequiredArgsConstructor;
 
+/** Task that need to be scheduled. */
 @Getter
 @RequiredArgsConstructor
 public class Task {
@@ -15,17 +16,24 @@ public class Task {
   /** The priority of the task. The higher the number, the higher the priority. */
   private int priority = 0;
 
+  /** The time that the task run. */
   private int elapsedTime = 0;
+
+  /** Whether the task is completed. */
   private boolean complete = false;
 
+  /** Create a task with id, total execution time and priority. */
   public Task(int id, int totalExecutionTime, int priority) {
     this.id = id;
     this.totalExecutionTime = totalExecutionTime;
     this.priority = priority;
   }
 
+  /** Execute the task for a given number of seconds. */
   public void execute(int seconds) {
-    if (complete) throw new IllegalStateException("Task already completed");
+    if (complete) {
+      throw new IllegalStateException("Task already completed");
+    }
 
     elapsedTime += seconds;
 

scheduler/src/main/java/com/iluwatar/scheduler/TaskScheduler.java

@@ -1,10 +1,10 @@
 package com.iluwatar.scheduler;
 
-
+/** The scheduler is responsible for scheduling tasks. */
 public interface TaskScheduler {
-  /** Add task to the scheduler */
+  /** Add task to the scheduler. */
   void scheduleTask(Task task);
 
-  /** Update to execute scheduled tasks */
+  /** Update to execute scheduled tasks. */
   void update(int deltaTime);
 }