JAVA: Main thread di Java - Revision history

Onnowpurbo at 03:46, 15 May 2022

2022-05-15T03:46:49Z

Onnowpurbo: /* Deadlocking with use of Main Thread(only single thread) */

2022-05-15T03:45:26Z

Deadlocking with use of Main Thread(only single thread)

Onnowpurbo: /* Cara Mengontrol Main thread */

2022-05-15T03:42:49Z

Cara Mengontrol Main thread

Onnowpurbo at 03:23, 15 May 2022

2022-05-15T03:23:32Z

Onnowpurbo at 03:19, 15 May 2022

2022-05-15T03:19:19Z

Onnowpurbo at 10:22, 11 May 2022

2022-05-11T10:22:50Z

Onnowpurbo at 10:20, 11 May 2022

2022-05-11T10:20:36Z

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Onnowpurbo: Created page with "Java provides built-in support for multithreaded programming. A multi-threaded program contains two or more parts that can run concurrently. Each part of such a program is cal..."

2022-05-09T04:29:21Z

Created page with "Java provides built-in support for multithreaded programming. A multi-threaded program contains two or more parts that can run concurrently. Each part of such a program is cal..."

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Java provides built-in support for multithreaded programming. A multi-threaded program contains two or more parts that can run concurrently. Each part of such a program is called a thread, and each thread defines a separate path of execution.
When a Java program starts up, one thread begins running immediately. This is usually called the main thread of our program because it is the one that is executed when our program begins.

There are certain properties associated with the main thread which are as follows:

It is the thread from which other “child” threads will be spawned.
Often, it must be the last thread to finish execution because it performs various shutdown actions
The flow diagram is as follows:

main thread in java

How to control Main thread

The main thread is created automatically when our program is started. To control it we must obtain a reference to it. This can be done by calling the method currentThread( ) which is present in Thread class. This method returns a reference to the thread on which it is called. The default priority of Main thread is 5 and for all remaining user threads priority will be inherited from parent to child.

Example

// Java program to control the Main Thread

// Importing required classes
import java.io.*;
import java.util.*;

// Class 1
// Main class extending thread class
public class Test extends Thread {

// Main driver method
public static void main(String[] args)
{

// Getting reference to Main thread
Thread t = Thread.currentThread();

// Getting name of Main thread
System.out.println("Current thread: "
+ t.getName());

// Changing the name of Main thread
t.setName("Geeks");
System.out.println("After name change: "
+ t.getName());

// Getting priority of Main thread
System.out.println("Main thread priority: "
+ t.getPriority());

// Setting priority of Main thread to MAX(10)
t.setPriority(MAX_PRIORITY);

// Print and display the main thread priority
System.out.println("Main thread new priority: "
+ t.getPriority());

for (int i = 0; i < 5; i++) {
System.out.println("Main thread");
}

// Main thread creating a child thread
Thread ct = new Thread() {
// run() method of a thread
public void run()
{

for (int i = 0; i < 5; i++) {
System.out.println("Child thread");
}
}
};

// Getting priority of child thread
// which will be inherited from Main thread
// as it is created by Main thread
System.out.println("Child thread priority: "
+ ct.getPriority());

// Setting priority of Main thread to MIN(1)
ct.setPriority(MIN_PRIORITY);

System.out.println("Child thread new priority: "
+ ct.getPriority());

// Starting child thread
ct.start();
}
}

// Class 2
// Helper class extending Thread class
// Child Thread class
class ChildThread extends Thread {

@Override public void run()
{

for (int i = 0; i < 5; i++) {

// Print statement whenever child thread is
// called
System.out.println("Child thread");
}
}
}
Output
Current thread: main
After name change: Geeks
Main thread priority: 5
Main thread new priority: 10
Main thread
Main thread
Main thread
Main thread
Main thread
Child thread priority: 10
Child thread new priority: 1
Child thread
Child thread
Child thread
Child thread
Child thread
Now let us discuss the relationship between the main() method and the main thread in Java. For each program, a Main thread is created by JVM(Java Virtual Machine). The “Main” thread first verifies the existence of the main() method, and then it initializes the class. Note that from JDK 6, main() method is mandatory in a standalone java application.

Deadlocking with use of Main Thread(only single thread)

We can create a deadlock by just using the Main thread, i.e. by just using a single thread.

Example

// Java program to demonstrate deadlock
// using Main thread

// Main class
public class GFG {

// Main driver method
public static void main(String[] args) {

// Try block to check for exceptions
try {

// Print statement
System.out.println("Entering into Deadlock");

// Joining the current thread
Thread.currentThread().join();

// This statement will never execute
System.out.println("This statement will never execute");
}

// Catch block to handle the exceptions
catch (InterruptedException e) {

// Display the exception along with line number
// using printStackTrace() method
e.printStackTrace();
}
}
}
Output:

Output explanation:
The statement “Thread.currentThread().join()”, will tell Main thread to wait for this thread(i.e. wait for itself) to die. Thus Main thread wait for itself to die, which is nothing but a deadlock.

==Referensi==

* https://www.geeksforgeeks.org/main-thread-java/

@@ Line 165: / Line 165: @@
 Output:
+[[File:Java-deadlock.png|center|300px|thumb]]
 Output explanation:

@@ Line 124: / Line 124: @@
 Hubungan antara metghod main() dan main thread di Java adalah sebagai berikut. Untuk setiap program, main thread dibuat oleh JVM (Java Virtual Machine). Thread "Main" pertama-tama memverifikasi keberadaan metode main(), dan kemudian menginisialisasi Class. Perhatikan bahwa dari JDK 6, metode main() adalah wajib dalam aplikasi java mandiri.
-==Deadlocking with use of Main Thread(only single thread)==
+==Deadlocking/kebuntuan dengan menggunakan Main Thread(hanya dengan menggunakan satu thread)==
-We can create a deadlock by just using the Main thread, i.e. by just using a single thread.
+Kita dapat membuat deadlock / kebuntuan hanya dengan menggunakan main thread, yaitu dengan hanya menggunakan satu thread.
 Contoh
@@ Line 171: / Line 169: @@
 Output explanation:
-The statement “Thread.currentThread().join()”, will tell Main thread to wait for this thread(i.e. wait for itself) to die. Thus Main thread wait for itself to die, which is nothing but a deadlock.
+Perintah "Thread.currentThread().join()", akan memberi tahu main thread untuk menunggu thread ini (yaitu menunggu dirinya sendiri) untuk selesai/mati. Jadi main thread menunggu dirinya sendiri untuk mati, yang tidak lain adalah jalan buntu.
 ==Referensi==
 * https://www.geeksforgeeks.org/main-thread-java/

@@ Line 13: / Line 13: @@
 ==Cara Mengontrol Main thread==
-The main thread is created automatically when our program is started. To control it we must obtain a reference to it. This can be done by calling the method currentThread( ) which is present in Thread class. This method returns a reference to the thread on which it is called. The default priority of Main thread is 5 and for all remaining user threads priority will be inherited from parent to child.
+Main thread dibuat secara otomatis ketika program kita dimulai. Untuk mengontrolnya kita harus mendapatkan referensi untuk itu. Ini dapat dilakukan dengan memanggil metode currentThread() yang ada di Thread Class. Method ini mengembalikan referensi ke thread yang dipanggil. Prioritas default dari main thread adalah 5 dan untuk semua prioritas user thread yang tersisa akan diwarisi dari parent ke child.
 Contoh
@@ Line 126: / Line 122: @@
   Child thread
-Now let us discuss the relationship between the main() method and the main thread in Java. For each program, a Main thread is created by JVM(Java Virtual Machine). The “Main” thread first verifies the existence of the main() method, and then it initializes the class. Note that from JDK 6, main() method is mandatory in a standalone java application.
+Hubungan antara metghod main() dan main thread di Java adalah sebagai berikut. Untuk setiap program, main thread dibuat oleh JVM (Java Virtual Machine). Thread "Main" pertama-tama memverifikasi keberadaan metode main(), dan kemudian menginisialisasi Class. Perhatikan bahwa dari JDK 6, metode main() adalah wajib dalam aplikasi java mandiri.
 ==Deadlocking with use of Main Thread(only single thread)==

@@ Line 1: / Line 1: @@
-Java provides built-in support for multithreaded programming. A multi-threaded program contains two or more parts that can run concurrently. Each part of such a program is called a thread, and each thread defines a separate path of execution.
+Java menyediakan dukungan bawaan untuk pemrograman multithread. Program multithread berisi dua atau lebih bagian yang dapat berjalan secara bersamaan. Setiap bagian dari program semacam itu disebut thread, dan setiap thread menentukan jalur eksekusi yang terpisah.
-There are certain properties associated with the main thread which are as follows:
+Ketika program Java dijalankan, satu thread segera mulai berjalan. Ini biasanya disebut main thread dari program kita karena ini adalah thread yang dieksekusi ketika program kita dimulai.
-[[File:Main-thread-in-java.jpeg|center|300px|thumb|main thread in java]]
+Flow Diagram adalah sebagai berikut:
+==Cara Mengontrol Main thread==
 The main thread is created automatically when our program is started. To control it we must obtain a reference to it. This can be done by calling the method currentThread( ) which is present in Thread class. This method returns a reference to the thread on which it is called. The default priority of Main thread is 5 and for all remaining user threads priority will be inherited from parent to child.

← Older revision		Revision as of 03:19, 15 May 2022
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	The flow diagram is as follows:		The flow diagram is as follows:

−	main thread in java	+
		+	[[File:Main-thread-in-java.jpeg\|center\|300px\|thumb\|main thread in java]]
		+