Question

Declare a class ComboLock that works like the combination lock in a school or gym locker..

The lock is constructed with a combination dial numbers between 0 and 39.

• The constructor sets the three "secret" numbers and the current position to 0.
• The reset method resets the dial so that it points to 0.
• The turnLeft and turnRight methods turn the dial by a given number of ticks to the left or right.
• The open method attempts to open the lock. The lock opens if the user first turned it right to the first number in the combination, then left to the second, and then right to the third. If the lock doesn't open, the lock is reset.
• The toString method should show current position of the lock's dial
• The getSolution method should return a String with the three "secret" numbers separated by spaces.
• The equals method should compare the three "secret" numbers of two locks (one the calling object, the other a parameter ComboLock object).

Here are the headings of the methods that should be included in your ComboLock class for this lab:

  public class ComboLock {
      . . .
      public ComboLock(int secret1, int secret2, int secret3) { ... }
      public void reset() { ... }
      public void turnLeft(int ticks) { ... }
      public void turnRight(int ticks) { ... }
            public boolean open() { ... }
      public String toString() { ... }
      public String getSolution() { ... }
      public boolean equals(ComboLock another){ ... }
  }  

You will need to determine the properties required to track the state of a ComboLock and how close a combination is to opening the lock.

Please remember to document your constants and methods using Javadoc-style comments and tags. Spend some time making your documentation useful, thorough, and easy to understand.

In a separate class, create a main method to test your class. Initialize a new ComboLock with combination 15 - 28 - 4. Demonstrate your ComboLock class by showing the results of the following attempts to open the lock:

• right 14, left 20 (34 ticks), right 4 (24 ticks)
• left 15, right 28, left 4
• right 15, left 28, right 8
• right 15, left 28
• right 15, left 28 (27 ticks), right 4 (16 ticks) - opens

Create another ComboLock object with a combination of your choice and demonstrate how it works, as well.

Finally compare the two locks using the equals method.

Answer 1

package mar10_20;
import java.util.Scanner;

/**
* A class to simulate a combination lock.
*/
public class ComboLock {
    int secret1, secret2, secret3;
    int dial = 0;
    int number1, number2, number3;
    int count = 0;

    public ComboLock() {
    }

    public ComboLock(int number1, int number2, int number3) {
        this.secret1 = number1;
        this.secret2 = number2;
        this.secret3 = number3;
    }

    public void setSecret1(int secret1) {
        this.secret1 = secret1;
    }

    public void setSecret2(int secret2) {
        this.secret2 = secret2;
    }

    public void setSecret3(int secret3) {
        this.secret3 = secret3;
    }

    public void reset() {
        this.dial = 0;
        this.number1 = 0;
        this.number2 = 0;
        this.number3 = 0;
        this.count = 0;
    }

    public void turnRight(int ticks) {
        this.dial = ticks;
        
        if (count == 0) {
            number1 = this.dial;
        }
        if (count == 2) {
            number3 = this.dial;
        }
        count++;
        
        if (count == 3) {
            count = 0;
        }
    }

    public void turnLeft(int ticks) {
        this.dial = ticks;
        if (count == 1) {
            number2 = this.dial;
            count++;
        }
    }

    public boolean open() {
        if (number1 == secret1 && number2 == secret2 && number3 == secret3) {
            return true;
        } else {
            return false;
        }
    }

    /**
     * Returns current value dial is pointing at
     *
     * @return value dial is pointing at currently
     */
    public int getCurrentNumber() {
        return dial;
    }
    
    public String toString() {
        return dial + "";
    }
    public String getSolution () {
        return secret1 + "-" + secret2 + "-" + secret3;
    }
    public boolean equals (ComboLock c) {
        return (secret1 == c.secret1) && (secret2 == c.secret2) && (secret3 == c.secret3);
    }

}


public class ComboLockDemo {

    public static void main(String[] args) {

        ComboLock clx = new ComboLock(15, 28, 4);
        clx.turnRight(14);
        clx.turnLeft(20);
        clx.turnRight(4);
        System.out.println(clx.open());
        
        clx.reset();
        clx.turnLeft(15);
        clx.turnRight(28);
        clx.turnLeft(4);
        System.out.println(clx.open());
        
        clx.reset();
        clx.turnRight(15);
        clx.turnLeft(28);
        clx.turnRight(8);
        System.out.println(clx.open());
        
        clx.reset();
        clx.turnRight(15);
        clx.turnLeft(28);
        System.out.println(clx.open());
        
        clx.reset();
        clx.turnRight(15);
        clx.turnLeft(28);
        clx.turnRight(4);
        System.out.println(clx.open());
        
    }

}

**************************************************

Thanks for your question. We try our best to help you with detailed answers, But in any case, if you need any modification or have a query/issue with respect to above answer, Please ask that in the comment section. We will surely try to address your query ASAP and resolve the issue.

Please consider providing a thumbs up to this question if it helps you. by Doing that, You will help other students, who are facing similar issue.