if和else陈述

Question

I'm trying to implement a toString method, and the output of the toString depends on the boolean variables. Below is my class and main.

public class Cell {

    public int addSpaces;
    boolean isEmpty;
    boolean isChute;
    boolean isLadder;

    public Cell() {
        addSpaces = 10; //I initialized addSpaces to 10 for testing purpose 
    }

    public boolean isChute() { //first boolean method
        if (addSpaces == -10) {
            return true;
        } else {
            return false;
        }
    }

    public boolean isLadder() {//second boolean method
        if (addSpaces == 10) {
            return true;
        } else {
            return false;
        }
    }

    public boolean isEmpty() { //third boolean method
        if (addSpaces == 0) {
            return true;
        } else {
            return false;
        }
    }

    public String toString() {
        String print;
        if (isChute = true) //if isChute is true return true.
        {
            print = "C10";       // toString output = "C10"
        } else if (isLadder = true) // if isLadder is true return true
        {
            print = "L10";          // toString output == "L10"
        } else {
            print = "---"; // else toString print output = "---"
        }
        return print;
    }

    public static void main(String[] arg) {
        Cell s = new Cell();

        System.out.println(s.addSpaces);
        System.out.println(s);
    }
}

Regardless of the input state of toString , I basically get the same output "C10".

Can someone tell me what I did wrong?

I'm new to this website so I appreciate any feedback for future reference. Thank you.

Answer 1

You've fallen into one of the languages "gotchas"

This...

if(isChute = true) //if isChute is true return true.
    print = "C10";       // toString output = "C10"
else if (isLadder = true) // if isLadder is true return true
    print = "L10";          // toString output == "L10"
else   
    print = "---"

is actually assigning true to isChute . You should be using == not =

Updated

A better approach would be...

if(isChute) //if isChute is true return true.
    print = "C10";       // toString output = "C10"
else if (isLadder) // if isLadder is true return true
    print = "L10";          // toString output == "L10"
else   
    print = "---"

If there are only two states that the object can be (either a chute or ladder), you could simply use

if(isChute) //if isChute is true return true.
    print = "C10";       // toString output = "C10"
else print = "L10";          // toString output == "L10"

If it can have more then 2 states then I would use an enum type instead.

Answer 2

isChute is assigned to true. So "C10" is being returned all the time by toString(). Change it

if(isChute){
    ...
}else if(isLadder){
    ...
}else{
    ..
}