[java design pattern] command pattern

Step 1: Establish a requester (commander) interface to encapsulate command execution

public interface Command {
    public void  exe();
}

Step 2: Create an interface implementation class, save the receiver instance, and rewrite the execution method of the command interface 

public class MyCommand implements Command {

	private Receiver receiver;
	
	public MyCommand(Receiver receiver) {
		this.receiver=receiver;
	}
	
	@Override
	public void exe() {
        receiver.action();
	}

}

Step 3: Command the receiver Receiver

public class Receiver {
    public void action() {
    	System.out.println("Command received");
    }
}

Step 4: Create the invoker Invoker 

public class Invoker {
   private Command command;
   public Invoker(Command command) {
	   this.command=command;
   }
   
   public void action() {
	   command.exe();
   }
}

Step 5: Test

public class Test {
      public static void main(String[] args) {
		Receiver receiver=new Receiver();
		Command command=new MyCommand(receiver);
		Invoker invoker=new Invoker(command);
		invoker.action();
		
	}
}