JAVA

java actionevent

public void actionPerformed(ActionEvent e) {
  
if(e.getSource()==button)  {
    button.setText("Button Clicked!");
  
}}

ActionEvent java swing

A semantic event which indicates that a component-defined action 
occurred. This high-level event is generated by a component 
(such as a Button) when the component-specific action occurs 
(such as being pressed). The event is passed to every ActionListener 
object that registered to receive such events using the component's 
addActionListener method.