Comparison operation has a lower priority than that of the concatenation operation.

System.out.println("Result: " + s1 == s2); 
// Evaluation flow: 
// "Result: " + s1 == s2 
// "Result: " + "str" == "str"  
// ("Result: " + "str") == "str" 
// "Result: str" == "str" 
// false