JFrame:setSize(int width, int height)

JFrame:setSize(int width, int height)

JFrame:setSize(int width, int height)  is a method that is used to set JFrame size.This method takes two integers which represent height and width.Other JFrame methods are setLocation,setJMenuBar etc.
Also JFrame window can implement WindowListener interface.

JFrame:setSize(int width, int height) Example

[

import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Font;

import javax.swing.JPanel;
import javax.swing.JFrame;


public class JFrameSetSize  extends JPanel{

    public void paint(Graphics g)
    {
        Dimension d=this.getPreferredSize();
        int fontSize=15;
        Font f=new Font("TmesRoman",Font.BOLD,fontSize);
        g.setFont(f);
        g.setColor(Color.BLUE);
        g.drawString("I love Programming in Java", 20, 20);

    }

    public static void main(String[] args) {
        JFrame f = new JFrame("JFrame:setSize(int width, int height)");
        f.getContentPane().add(new JFrameSetSize());

        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        f.setSize(300,300);
        f.setLocationRelativeTo(null);
        f.setVisible(true);

    }

}

]

Code Explanation

• Code [JFrame f = new JFrame("JFrame:setSize(int width, int height)");] creates a new JFrame window with a tittle.
• [ f.getContentPane().add(new JFrameSetSize());]-adds JPanel contents to the JFrame.
• [ f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);]-sets Default close operation when the close button is clicked.
• [f.setSize(300,300);]-sets JFrame window size.
• [f.setLocationRelativeTo(null);]-positions JFrame window at the center of the screen.
• [f.setVisible(true);]-makes the window visible.

Setting JFrame Window size using Dimension class.

[

import java.awt.Color;
import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Font;

import javax.swing.JPanel;
import javax.swing.JFrame;


public class JFrameSetSize  extends JPanel{

    public void paint(Graphics g)
    {
        Dimension d=this.getPreferredSize();
        int fontSize=15;
        Font f=new Font("TmesRoman",Font.BOLD,fontSize);
        g.setFont(f);
        g.setColor(Color.BLUE);
        g.draw3DRect(100, 100,100, 100, false);
    }

    public static void main(String[] args) {
        JFrame f = new JFrame("JFrame:setSize(int width, int height)");
        f.getContentPane().add(new JFrameSetSize());

        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        f.setSize(new Dimension(400,400));
        f.setLocationRelativeTo(null);
        f.setVisible(true);

    }

}

]

Output

Code Explanation

Above class extends JPanel Swing component and that the reason why we can access [public void paint(Graphics g)] method.

Below code creates a 3D rectangle object.

[public void paint(Graphics g)

    {
        Dimension d=this.getPreferredSize();
        int fontSize=15;
        Font f=new Font("TmesRoman",Font.BOLD,fontSize);
        g.setFont(f);
        g.setColor(Color.BLUE);
        g.draw3DRect(100, 100,100, 100, false);

    }]

[f.setSize(new Dimension(400,400));]-sets JFrame window size using Dimension class.