Thread: Java Programming: Learning the roots

Books:

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Java PDF Book

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Tutorials/Snippets:

Tuts For JAVA SE


Resources:

Tools by oracle

Programs Built For Coding Purposes:
Eclipse
IntelliJ
NetBeans
NotePad++


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DreamInCode(DIC for Short)
Java Programming Forums



Some Basic Coding And Understanding:
(Using the 2 Class Method)



Class1.java

Code:

import javax.swing.JFrame;

public class Class1 {

	public static void main(String[] args) {
		
		Class2 mainframe = new Class2();
		mainframe.setSize(420,315);
		mainframe.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		mainframe.setResizable(false);
		mainframe.setVisible(true);

		
	}

}

Spoiler for Explaining Class1.java:

import javax.swing.JFrame;
Calling Form Java's Api Rather Than Writing 20+ Lines of Code, Import are time savers.

public class Class1 {
Name of the class: The Class is Public.

public static void main(String[] args) {

The method is public because it be accessible to the JVM to begin execution of the program.

It is Static because it be available for execution without an object instance. you may know that you need an object instance to invoke any method. So you cannot begin execution of a class without its object if the main method was not static.

It returns only a void because, once the main method execution is over, the program terminates. So there can be no data that can be returned by the Main method

The last parameter is String args[]. This is used to signify that the user may opt to enter parameters to the java program at command line. We can use both String[] args or String args[]. The Java compiler would accept both forms.

Class2 mainframe = new Class2();
The information that you will be putting onto the jframe will come from class2.java.

mainframe.setSize(420,315);
JFrame Size.

mainframe.setDefaultCloseOperation(JFrame.EXIT_ON_ CLOSE);
Closes The Jframe When you exit, Rather than leaving it running in the background.

mainframe.setResizable(false);
JFrame cannot be pulled to be resized.

mainframe.setVisible(true);
The JFrame is Visible.


}
ends public static void main(String[] args).

}
ends public class Class1

Class2.java

Code:

import java.awt.FlowLayout;
import javax.swing.JFrame;



public class Class2 extends JFrame {
	
	
	public Class2(){

		super("");
		setLayout( new FlowLayout());
		
        
	}
}

Spoiler for Explaining Class2.java:

import java.awt.FlowLayout;
import javax.swing.JFrame;
Calling Form Java's Api Rather Than Writing 20+ Lines of Code, Import are time savers.


public class Class2 extends JFrame {

The Class is public: The Class name is Class2, It extends JFrame (As in: It is like saying "Hey, Put this crap on the Jframe that It wants you to do in class1.java")


public Class2(){
Class is public: The Class name is Class2, You will begin coding after her, For the line above is the add the imports that you want to be on the Jframe.

super("");
The JFrames Title, The title has to be the the quotation marks. Ex. super("Rune-Server");
setLayout( new FlowLayout());
Send the title Left to right.


}
ends public Class2().
}
ends public class Class2 extends JFrame.

Assuming You have a basic knowledge Of Java, Lets Get to a little programming, In This Part of The tutorial i will be teaching you how to make a simple Calculator that the problem displays into a jframe.

Class1.java Will Stay The Same: Don't Edit it threw out this part of the tutorial



Class2.java

Code:

import java.awt.FlowLayout;
import java.util.*;
import javax.swing.JFrame;
import javax.swing.JLabel;



public class Class2 extends JFrame {
	
	private JLabel sum2;
	Scanner input = new Scanner (System.in);
	
    int num1 = 0;
    int num2 = 0;
	  int sum = num1 + num2;
	
	public Class2(){

		super("");
		setLayout( new FlowLayout());
		
		System.out.printf("First Number:");
		num1 = input.nextInt();
		System.out.printf("Second Number:");
		num2 = input.nextInt();
		sum = num1 + num2;
		
		sum2 = new JLabel(""+num1+" + "+num2+" = "+sum);
		add(sum2);
		
        
        
	}
}

Spoiler for Explaining Class2.java Update:

Code:

import java.util.*;
Imports Everything for the API For Util.

import javax.swing.JLabel;
Imports JLabel, So words can be Printed Onto A JFrame.



	
	private JLabel sum2;
This JLabel can only be used in class2.java, The JLabel's name is sum2.

	Scanner input = new Scanner (System.in);
Scans for the number they will be put in to add up your sum.
	
    int num1 = 0;
Number 1.
    int num2 = 0;
Number 2.

	  int sum = num1 + num2;
Number 1 + Number 2 = Sum.
		
                System.out.printf("First Number:");
Displays "First Number:"

		num1 = input.nextInt();
Adds the 1st Number To The int num1.

		System.out.printf("Second Number:");
Displays "Second Number:"

		num2 = input.nextInt();
Adds the 2ed Number To The int num2.

		sum = num1 + num2;
Combines/Adds Number 1 with number 2. 
(Final Product, Adds the number that have been recently added in, if this is not here the sum will be 0.)
		
		sum2 = new JLabel(""+num1+" + "+num2+" = "+sum);
Tells the JLabel to print Number 1 + Number 2 = Sum.

		add(sum2);
Add the JLabel To The Jframe.

Class1.java

Code:

import javax.swing.JFrame;
public class Class1 {

	public static void main(String[] args) {
	Class2 mainframe = new Class2();
	mainframe.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
	mainframe.setSize(250,120);
	mainframe.setVisible(true);
	mainframe.setResizable(false);

	}

}

Class2.java

Code:

import java.awt.FlowLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JTextField;


public class Class2 extends JFrame {
	
	private JLabel username;
	private JTextField username2;
	private JLabel password;
	private JTextField password2;
	private JButton login;
	
	public Class2(){
		super("Dashboard");
		setLayout( new FlowLayout());
		
		
		username = new JLabel ("Username: ");
		add(username);
		
		username2 = new JTextField("",12);
		add(username2);
		
		password = new JLabel ("Password: ");
		add(password);
		
		password2 = new JTextField("",12);
		add(password2);
		
		login = new JButton (" Login ");
		add(login, FlowLayout.TRAILING);
		
		login.addActionListener(new ActionListener() {
			public void actionPerformed(ActionEvent event) {
		
		if(username2.getText().equals("Kevin") && password2.getText().equals("IDK"))
		System.out.println("Welcome Kevin!");
		
		else if(username2.getText().equals("Rune-Server") && password2.getText().equals("Baws"))
		System.out.println("Well isnt that just Baws.");
		
		else{
		System.out.println("Username or password incorrect.");
		
	}
		}
		});
}
}

Hope you can learn something from this, If you have any questions: Reply Below or send me a Pm. Thanks.