Thread: Why it is not coming out of while loop, when 'a' = 'b'?

public class App {
public static void main(String[] args) throws Exception {
String a = "";
String b = "Stop";
int i = 1;

while (a!=b) {
System.out.println("Its running");
a = a+(b.charAt(i-1));
i++;
}
}
}

In Java, when comparing strings with != or == operators, you're actually comparing references, not the content of the strings themselves. Even if the content of a and b is the same, the references may not be equal, which is why your loop doesn't terminate when a becomes equal to b.

To compare the content of strings, you should use the equals() method. while (!a.equals(b))