02. Save Records in Parallel

src/main/java/Service/StudentService.java

@@ -12,6 +12,7 @@ public class StudentService {
         } catch (InterruptedException e) {
             throw new RuntimeException(e);
         }
+        System.out.println("Student "+ std.getName()+ " is saved.");
         return UUID.randomUUID().toString();
     }
 }

src/main/java/StudentThread.java

+import Resource.Student;
+import Service.StudentService;
+
+public class StudentThread extends Thread {
+
+    private Student student;
+    private StudentService studentService;
+
+    public StudentThread(Student student, StudentService studentService) {
+        this.student = student;
+        this.studentService = studentService;
+    }
+
+    @Override
+    public void run() {
+        System.out.println("Name of current Thread: "+Thread.currentThread().getName());
+        studentService.saveStudent(student);
+    }
+}

src/main/java/Threads.java

-public class Threads {
-}

src/test/java/ThreadTest.java

@@ -2,6 +2,9 @@ import Resource.Student;
 import Service.StudentService;
 import junit.framework.TestCase;
 
+import java.util.ArrayList;
+import java.util.List;
+
 public class ThreadTest extends TestCase {
 
     public void testStudent() {
@@ -17,4 +20,73 @@ public class ThreadTest extends TestCase {
         System.out.println("Execution Time: " + execTime + " ms");
 
     }
+
+    public void testStudentThread() {
+        long start = System.currentTimeMillis();
+
+        System.out.println("Name of current Thread: "+Thread.currentThread().getName());
+
+        StudentService studentService = new StudentService();
+        Student std = new Student("student");
+
+        StudentThread studentThread = new StudentThread(std, studentService);
+        studentThread.setName("myThread");
+        studentThread.start(); // start thread
+//        studentThread.run(); // treat as a simple object not as a thread
+        try {
+            studentThread.join();
+        } catch (InterruptedException e) {
+            throw new RuntimeException(e);
+        }
+        long execTime = System.currentTimeMillis() - start;
+        System.out.println("Execution Time: " + execTime + " ms");
+    }
+
+    public void testStudentsThreads(){
+        long start = System.currentTimeMillis();
+
+        StudentService studentService = new StudentService();
+
+        for (int i=1;i<=10;++i){
+
+            Student std = new Student("student "+i);
+            StudentThread studentThread = new StudentThread(std, studentService);
+            studentThread.setName("myThread-"+i);
+            studentThread.start(); // start thread
+            //        studentThread.run(); // treat as a simple object not as a thread
+            try {
+                studentThread.join(); //wait thread to complete
+            } catch (InterruptedException e) {
+                throw new RuntimeException(e);
+            }
+        }
+        long execTime = System.currentTimeMillis() - start;
+        System.out.println("Execution Time: " + execTime + " ms");
+    }
+
+    public void testStudentThreadsPP(){
+        long start = System.currentTimeMillis();
+
+        StudentService studentService = new StudentService();
+        List<StudentThread> studentThreads = new ArrayList<>();
+        for (int i=1;i<=10;++i){
+
+            Student std = new Student("student "+i);
+            StudentThread studentThread = new StudentThread(std, studentService);
+            studentThread.setName("myThread-"+i);
+            studentThread.start(); // start thread
+            studentThreads.add(studentThread);
+            //        studentThread.run(); // treat as a simple object not as a thread
+        }
+
+        studentThreads.forEach(e -> {
+            try {
+                e.join(); //wait thread to complete
+            } catch (InterruptedException ex) {
+                throw new RuntimeException(ex);
+            }
+        });
+        long execTime = System.currentTimeMillis() - start;
+        System.out.println("Execution Time: " + execTime + " ms");
+    }
 }