A JPanel is a subclass of JComponent class and it is an invisible component in Java. The FlowLayout is a default layout for a JPanel. We can add most of the components like buttons, text fields, labels, tables, lists, trees,  etc. to a JPanel.We can also add multiple sub-panels to the main panel using the add() method of Container class.Syntaxpublic Component add(Component comp)Exampleimport java.awt.*; import javax.swing.*; public class MultiPanelTest extends JFrame {    private JPanel mainPanel, subPanel1, subPanel2;    public MultiPanelTest() {       setTitle("MultiPanel Test");       mainPanel = new JPanel(); // main panel       mainPanel.setLayout(new GridLayout(3, 1));       mainPanel.add(new JLabel("Main ... Read More

Generics is a concept in Java where you can enable a class, interface and, method, accept all (reference) types as parameters. In other words it is the concept which enables the users to choose the reference type that a method, constructor of a class accepts, dynamically. By defining a class as generic you are making it type-safe i.e. it can act up on any datatype.To define a generic class you need to specify the type parameter you are using in the angle brackets “” after the class name and you can treat this as datatype of the instance variable an ... Read More

Whenever you want to restrict the type parameter to subtypes of a particular class you can use the bounded type parameter. If you just specify a type (class) as bounded parameter, only sub types of that particular class are accepted by the current generic class. These are known as bounded-types in generics in Java.Defining bounded-types for classYou can declare a bound parameter just by extending the required class with the type-parameter, within the angular braces as −class Sample ExampleIn the following Java example the generic class Sample restricts the type parameter to the sub classes of the Number classes using ... Read More

Whenever you want to restrict the type parameter to subtypes of a particular class you can use the bounded type parameter. If you just specify a type (class) as bounded parameter, only sub types of that particular class are accepted by the current generic class.You can declare a bound parameter just by extending the required class with the type-parameter, within the angular braces as −class Sample Example Live DemoIn the following Java example the generic class Sample restricts the type parameter to the sub classes of the Number classes using the bounded parameter.class Sample {    T data;    Sample(T data){ ... Read More

Generics is a concept in Java where you can enable a class, interface and, method, accept all (reference) types as parameters. In other words it is the concept which enables the users to choose the reference type that a method, constructor of a class accepts, dynamically. By defining a class as generic you are making it type-safe i.e. it can act up on any datatype.To define a generic class you need to specify the type parameter you are using in the angle brackets “” after the class name and you can treat this as datatype of the instance variable an ... Read More

Arrays in Java are used to store homogeneous datatypes, where generics allow users to dynamically choose the type (class) that a method, constructor of a class accepts, dynamically.By defining a class generic you are making it type-safe i.e. it can act up on any datatype. To understand generics let us consider an example −Example Live Democlass Student{    T age;    Student(T age){       this.age = age;    }    public void display() {       System.out.println("Value of age: "+this.age);    } } public class GenericsExample {    public static void main(String args[]) {       Student ... Read More

Generics is a concept in Java where you can enable a class, interface and, method, accept all (reference) types as parameters. In other words it is the concept which enables the users to choose the reference type that a method, constructor of a class accepts, dynamically. By defining a class as generic you are making it type-safe i.e. it can act up on any datatype.To define a generic class you need to specify the type parameter you are using in the angle brackets “” after the class name and you can treat this as datatype of the instance variable an ... Read More

Similar to generic classes you can also define generic methods in Java. These methods use their own type parameters. Just like local variables, the scope of the type parameters of the methods lies within the method.While defining a generic method you need to specify the type parameter within the angle brackets (< T >). This should be placed before the method's return type.You can have multiple type parameters separated by commas. A type parameter, also known as a type variable, is an identifier that specifies a generic type name.The type parameters can be used to declare the return type and ... Read More

Generics is a concept in Java where you can enable a class, interface and, method, accept all (reference) types as parameters. In other words it is the concept which enables the users to choose the reference type that a method, constructor of a class accepts, dynamically. By defining a class as generic you are making it type-safe i.e. it can act up on any datatype.To define a generic class you need to specify the type parameter you are using in the angle brackets “” after the class name and you can treat this as datatype of the instance variable an ... Read More

Generics is a concept in Java where you can enable a class, interface and, method, accept all (reference) types as parameters. In other words it is the concept which enables the users to choose the reference type that a method, constructor of a class accepts, dynamically. By defining a class as generic you are making it type-safe i.e. it can act up on any datatype.To define a generic class you need to specify the type parameter you are using in the angle brackets “” after the class name and you can treat this as datatype of the instance variable an ... Read More