To set the margins i.e. row and columns margins between cells of a table, use the setIntercellSpacing() method −Dimension dim = new Dimension(50, 2); table.setIntercellSpacing(new Dimension(dim));Above, we have used the Dimension class −The following is an example to set margins between cells of a JTable cell −Examplepackage my; import java.awt.Dimension; import javax.swing.JFrame; import javax.swing.JPanel; import javax.swing.JRootPane; import javax.swing.JScrollPane; import javax.swing.JTable; import javax.swing.table.DefaultTableModel; public class SwingDemo {    public static void main(String[] argv) throws Exception {       JFrame frame = new JFrame("Demo");       JPanel panel = new JPanel();       String data[][] = {     ... Read More

To display both horizontal and vertical grid lines in a table, use the setShowGrid() method and set it to true − The setShowGrid() method is used in graphical user interfaces or data visualization tools to control the visibility of grid lines in a component, like a chart or a table. table.setShowGrid(true); JTable is a class in the Java Swing library, part of the JFC(Java Foundation Classes). It creates and manages tables in a GUI(graphical user interface) application. Syntax void setShowGrid(boolean showGrid) Parameter showGrid: A boolean that determines grid line visibility for both horizontal and vertical lines is true ... Read More

To set the grid color of a table, use the setGridColor() method.table.setGridColor(Color.yellow);Above, we have used the Color class to set the color.The following is an example to set the grid color of a table −Examplepackage my; import java.awt.Color; import javax.swing.BorderFactory; import javax.swing.JFrame; import javax.swing.JPanel; import javax.swing.JScrollPane; import javax.swing.JTable; import javax.swing.border.TitledBorder; public class SwingDemo {    public static void main(String[] args) {       JFrame frame = new JFrame();       JPanel panel = new JPanel();       panel.setBorder(BorderFactory.createTitledBorder(          BorderFactory.createEtchedBorder(), "ODI Rankings", TitledBorder.CENTER, TitledBorder.TOP));       String[][] rec = {       ... Read More

At first, set the setShowGrid() to FALSE to disable all the grid lines. To display only horizontal grid lines in a table, set the method setShowHorizontalLines() to TRUE. Let us first create a table with rows and columns −String[][] rec = {    { "1", "Steve", "AUS" },    { "2", "Virat", "IND" },    { "3", "Kane", "NZ" },    { "4", "David", "AUS" },    { "5", "Ben", "ENG" },    { "6", "Eion", "ENG" }, }; String[] header = { "Rank", "Player", "Country" }; JTable table = new JTable(rec, header);Now, display only horizontal grid lines −table.setShowGrid(false); table.setShowHorizontalLines(true);The following ... Read More

At first, set the setShowGrid() to FALSE to disable all the grid lines. To display only vertical grid lines in a table, set the method setShowVerticalLines() to TRUE. Let us first create a table with rows and columns −String[][] rec = {    { "1", "Steve", "AUS" },    { "2", "Virat", "IND" },    { "3", "Kane", "NZ" },    { "4", "David", "AUS" },    { "5", "Ben", "ENG" },    { "6", "Eion", "ENG" }, }; String[] header = { "Rank", "Player", "Country" }; JTable table = new JTable(rec, header);Now, display only vertical grid lines −table.setShowGrid(false); table.setShowVerticalLines(true);The ... Read More

Let’s say the following is our table −String[][] rec = {    { "1", "Steve", "AUS" },    { "2", "Virat", "IND" },    { "3", "Kane", "NZ" },    { "4", "David", "AUS" },    { "5", "Ben", "ENG" },    { "6", "Eion", "ENG" }, }; String[] header = { "Rank", "Player", "Country" }; JTable table = new JTable(rec, header);Prevent displaying grid lines −table.setShowGrid(false);The following is an example to prevent displaying grid lines −Examplepackage my; import java.awt.Color; import javax.swing.BorderFactory; import javax.swing.JFrame; import javax.swing.JPanel; import javax.swing.JScrollPane; import javax.swing.JTable; import javax.swing.border.TitledBorder; public class SwingDemo {    public static void main(String[] ... Read More

To expand JTree row to display all the nodes and child nodes, use the expandRow() method in Java. At first, create a node −DefaultMutableTreeNode node = new DefaultMutableTreeNode("Project");Now, add nodes to the node created above −DefaultMutableTreeNode node1 = new DefaultMutableTreeNode("App"); DefaultMutableTreeNode node2 = new DefaultMutableTreeNode("Website"); DefaultMutableTreeNode node3 = new DefaultMutableTreeNode("WebApp"); node.add(node1); node.add(node2); node.add(node3);Now, create more nodes and set them as child nodes for the nodes we creted above −DefaultMutableTreeNode one = new DefaultMutableTreeNode("Learning website"); DefaultMutableTreeNode two = new DefaultMutableTreeNode("Business website"); DefaultMutableTreeNode three = new DefaultMutableTreeNode("News publishing website"); DefaultMutableTreeNode four = new DefaultMutableTreeNode("Android app"); DefaultMutableTreeNode five = new DefaultMutableTreeNode("iOS app"); DefaultMutableTreeNode ... Read More

To create a Titleless and Borderless JFrame, use the setUndecorated() method and set it to TRUE −JFrame frame = new JFrame("Register!"); frame.setUndecorated(true);The following is an example to create a titleless and borderless JFrame −Examplepackage my; import java.awt.GridLayout; import javax.swing.JFrame; import javax.swing.JLabel; import javax.swing.JPasswordField; import javax.swing.JTextField; import javax.swing.SwingConstants; public class SwingDemo {    public static void main(String[] args) throws Exception {       JFrame frame = new JFrame("Register!");       JLabel label1, label2, label3;       frame.setLayout(new GridLayout(2, 2));       label1 = new JLabel("Id", SwingConstants.CENTER);       label2 = new JLabel("Age", SwingConstants.CENTER);       ... Read More

A static variable gets created at the time of class loading even before the execution of a static block and the purpose of the static block is to assign value to the static variables. A static variable stores a value that is shared between all instances of the class it is defined in and a static block is a section of code that gets executed when class is first loaded. If we want any logic that needs to be executed at the time of class loading that logic needs to place inside the static block so that it will be executed ... Read More

The error that occurs at runtime after successful compilation of the Java program is called a runtime error or unchecked exception. It disrupts the normal flow of a program’s execution and terminates the program abruptly.These errors are not detected by the compiler but by JVM. The runtime errors in Java are represented by a class called RuntimeException. In this article, we are going to learn what RuntimeException is and its common types. Also, we will discuss how to handle RuntimeException in Java. What is RuntimeException in Java? In Java, the RuntimeException of the java.lang package is a parent class of ... Read More