In C or C++, we cannot create random float directly. We can create random floats using some trick. We will create two random integer values, then divide them to get random float value.Sometimes it may generate an integer quotient, so to reduce the probability of that, we are multiplying the ... Read More

To get directories from JFileChoose, use the mode setFileSelectionMode −JFileChooser file = new JFileChooser(); file.setFileSelectionMode(JFileChooser.DIRECTORIES_ONLY);The following is an example to get Directories from JFileChooser −Exampleimport javax.swing.JFileChooser; public class SwingDemo {    public static void main(String[] args) {       JFileChooser file = new JFileChooser(); file.setMultiSelectionEnabled(false);         ... Read More

Here we will see how to sleep for x (given by user) milliseconds in C++ program.To do this thing we can use different libraries. But here we are using the clock() function. The clock() will return the current CPU time. Here we will try to find the ending time from ... Read More

To create a JFrame with no border and title bar, use setUndecorated() −JFrame frame = new JFrame(); frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); frame.setPreferredSize(new Dimension(400, 300)); frame.setUndecorated(true);The following is an example to create JFrame with no border and title bar −Exampleimport java.awt.Dimension; import java.awt.event.ActionEvent; import javax.swing.AbstractAction; import javax.swing.JButton; import javax.swing.JFrame; import javax.swing.JLabel; import javax.swing.JPanel; public ... Read More

To add background image to JFrame, use the getImage() method of the Image class −Image img = Toolkit.getDefaultToolkit().getImage("E:\rahul.jpg");Now, draw the image −public void paintComponent(Graphics g) {    super.paintComponent(g);    g.drawImage(img, 0, 0, null); }The following is an example to add Background Image to JFrame −Exampleimport java.awt.Graphics; import java.awt.Image; import java.awt.Toolkit; ... Read More

To select the second index, use the setSelectedIndex() method −JList new JList(sports); list.setSelectedIndex(2);The following is an example to select the second index in Java JList −Examplepackage my; import java.awt.event.*; import java.awt.*; import javax.swing.*; class SwingDemo extends JFrame {    static JFrame frame;    static JList list;    public static void ... Read More

To get JFrame window size information, you can use the following −environment.getMaximumWindowBounds();For Screen Size −config.getBounds()For Frame Size −frame.getSize());The following is an example to get JFrame window size information −Exampleimport java.awt.GraphicsConfiguration; import java.awt.GraphicsDevice; import java.awt.GraphicsEnvironment; import java.awt.Rectangle; import javax.swing.JFrame; public class SwingDemo {    public static void main(String[] args) {   ... Read More

To set default button for JFrame, use the setDefaultButton() method −JFrame frame = new JFrame(); frame.getRootPane().setDefaultButton(button);The following is an example to set default button for JFrame −Exampleimport java.awt.event.ActionEvent; import java.awt.event.ActionListener; import java.awt.event.KeyEvent; import javax.swing.JButton; import javax.swing.JFrame; public class SwingDemo {    public static void main(String args[]) {       ... Read More

At first, set an undecorated frame −setUndecorated(true);Now draw a border −getRootPane().setBorder (.createMatteBorder(3, 3, 3, 3, Color.ORANGE));The following is an example to draw a border around an undecorated JFrame −Exampleimport java.awt.BorderLayout; import java.awt.Color; import java.awt.Dimension; import javax.swing.BorderFactory; import javax.swing.JFrame; import javax.swing.JLabel; public class SwingDemo extends JFrame {    JLabel label = ... Read More

We can get the memory usage like virtual memory usage or resident set size etc. at run time. To get them we can use some system libraries. This process depends on operating systems. For this example, we are using Linux operating system.So here we will see how to get the ... Read More