Java Object 相等方法和布尔值

Question

I have the following code snippet

  format(Object obj) {
    if(obj.equals("false")) {
      buffer.append("No");
    } else {
      buffer.append("Yes");
    }
  }

When debugging, I verify that the value of obj variable is a Boolean object with the value "false", but the if clause always go to the Yes instruction. Can you help me understand why?

Answer 1

When you run obj.equals("false") you're trying to compare obj , a Boolean , with "false" , which is a String .

So you can try to first convert the Boolean to a string:

if(obj.toString().equals("false")){
    buffer.append("No");
} else {
    buffer.append("Yes");
}

Or, even better, as suggested by @Nexevis, you can compare obj directly to a Boolean :

if(obj.equals(false)){
    buffer.append("No");
} else {
    buffer.append("Yes");
}