toString and booleans

Question

I am making a class for a lightbulb and I have to have it be on/off state whether it's burntout or not, and its color. For whatever reason I get the right things to switch but, my toString prints the wrong answer and I cannot figure out why. I am not used to working with booleans and so my code may not support my logic. Can someone help?

Here is the code:

public class Light
{
 // Variables that will be initialized in the Light constructors.

 private boolean on;
 private boolean burntOut;
 private String color = "";

 // Default constructor that sets the bulb to on, not burnt out, and "white".

 public Light()
 {
  on= true;
  burntOut = false;
  color = "white";
 }

 // This constructor sets the variable "on" to the parameter o. The burntOut
 // variable is set to the parameter b. If burntOut
 // is true, on is set to false, no matter what value is stored in o.
 // The color variable is set to the parameter c only if c is "red", "green"
 // or "blue". The constructor ignores the case of the value in c. If c holds
 // any value other than "red", "green" or "blue", the constructor sets
 // color to "white".

 public Light(boolean o, boolean b, String c)
 {
on = o;
burntOut=b;
  if(burntOut=true){
    on = false;
  }
  else{
    on= o;
  }
  if(c.equalsIgnoreCase("red")){
    color = "red"; 
  }
  if(c.equalsIgnoreCase("blue")){
    color = "blue";
  }
  if (c.equalsIgnoreCase("green")){
    color="green";
  }
  else {
    color = "white";
  }

 }

 // The toString method returns a String with the Light in the format:
 // off red    burnt out
 // on green    not burnt out
 //
 // Notice there is one space between "off"/"on" and the value for color,
 // and a tab before the "burnt out" or "not burnt out".

 public String toString()
 {
  String x ="";
       if(on = true){
         x+="on" + " ";
       }
       if(on = false){
         x+= "off" + " ";
       }

       x+= color;

       if (burntOut = false){
         x+="\t" + "not burnt out";
       }
       if(burntOut = true){
         x+= "\t" + "burnt out";
       }


  return x;
 }

And here is a test the project is allowing me to run to show my results:

> run Light

1. Test Light() * PASS: on is set correctly (true) PASS: burntOut is set correctly (false) PASS: color is set correctly (white) * FAIL: toString does not work as expected (on white burnt out)

Test Light(boolean b, boolean o, String c) * PASS: on is set correctly (false) PASS: burntOut is set correctly (true) PASS: color is set correctly (green) * FAIL: toString does not work as expected (on green burnt out)

This is where you making mistake, if(burntOut=true){ on = false; } should be if(burntOut == true){ on = false; } Check every step proper. — Kishan Bheemajiyani, Feb 08 '16 at 15:44

score 0 · Accepted Answer · answered Feb 08 '16 at 15:40

0

This:

if(on = true){

You're not comparing, you're assigning the value. To compare, use ==:

if(on == true){

Or, even simpler:

if(on){

(Note: There are several places in your code which have this error. This is illustrating only one of them. Fix the others accordingly as well.)

answered Feb 08 '16 at 15:40

David

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That is correct. +1 for that. – Kishan Bheemajiyani Feb 08 '16 at 15:44
this makes so much sense thank you for reminding of such a simple rule! – Bob D Feb 08 '16 at 15:45
@BobD: One thing that might help as you move forward is to consider the semantic names of your variables. For example, if the variable `on` is called something like `isOn` then the code might be something like: `if (this.isOn)` which reads semantically very clearly as "if this is on". – David Feb 08 '16 at 15:46

toString and booleans

1 Answers1