Java program on Command design pattern

Save each class in a separate file with the class name and execute the Main.java program. Some classes are not used in the main execution. In later versions of this design I will include them.

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package org.learn.designpatterns.command;

//This class(Main.java) is client part of command design pattern
public class Main {

    public static void main(String args[]) {
        CommandManager mgr = new CommandManager();
        // CommandManager is Invoker part of command design pattern
        Command tomcat = new TomcatStartCommand();
        // In TomcatStartCommand class I used Tomcat class. Here Tomcat class is
        // the receiver part of command design pattern
        Command serviceMix = new ServiceMixStartCommand();
        mgr.addCommand(tomcat);
        mgr.addCommand(serviceMix);
        mgr.runCommands();
    }

}
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package org.learn.designpatterns.command;

public interface Command {
   
    public void execute();

}
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package org.learn.designpatterns.command;

public class CommandException extends Exception {
   
    private String message;
   
    public CommandException(String message){
        super(message);
        this.message=message;
    }
   
    public CommandException(){
        super();
    }
   
    public void setMessage(String message){
        this.message = message;
    }
   
    public String getMessage(){
        return message;
    }
   
}
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package org.learn.designpatterns.command;

import java.util.ArrayList;

public class CommandManager {

    private List<Command> commandList = new ArrayList();

    public void runCommands() {
        for (Command c : commandList) {
            c.execute();
        }
    }

    public void addCommand(Command command) {
        commandList.add(command);
    }
}

class TomcatStartCommand implements Command {

    Tomcat tomcat = new Tomcat();

    @Override
    public void execute() {
        tomcat.startTomcat();
    }
}

class TomcatStopCommand implements Command {

    Tomcat tomcat = new Tomcat();

    @Override
    public void execute() {
        tomcat.stopTomcat();
    }
}

class ServiceMixStopCommand implements Command {
    ServiceMix serviceMix = new ServiceMix();

    @Override
    public void execute() {
        serviceMix.stopServiceMix();
    }

}

class ServiceMixStartCommand implements Command {
    ServiceMix serviceMix = new ServiceMix();

    @Override
    public void execute() {
        serviceMix.startServiceMix();
    }

}
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package org.learn.designpatterns.command;

public class ServiceMix {
   
    public boolean stopServiceMix(){
        System.out.println("Service Mix is stopped");
        return true;
    }
   
    public boolean startServiceMix(){
        System.out.println("Service Mix is started");
        return true;
    }

}
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package org.learn.designpatterns.command;

public class Status {
    private String status;

    public String getStatus() {
        return status;
    }

    public void setStatus(String status) {
        this.status = status;
    }
   
   
}
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package org.learn.designpatterns.command;

public class Tomcat {
   
    public boolean stopTomcat(){
        System.out.println("Tomcat Stopped");
        return true;
    }
   
    public boolean startTomcat(){
        System.out.println("Tomcat Started");
        return true;
    }

}
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