Check out example codes for "java swing timer sleep". It will help you in understanding the concepts better.

Code Example 1

System.out.println("Hi");
//Now it will pause
try{
  Thread.sleep(5000)//Time in milliseconds->5000==5 seconds 
  //^freezes whole program for amount of time
  System.out.println("Hola");//Appears after 5 seconds
}
catch(InterruptedException e){
  System.err.println(e.getMessage());
}

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