toLowerCase() strange behaviour

Question

toLowerCase() converts the string to lowercase but when i use it in a logic it gives bizarre results. I can do the logic in some other way without even using toLowerCase() but please tell me what's wrong here

char gender = 'M';
System.out.println((gender+"").toLowerCase());          //prints "m"
System.out.println((gender+"").toLowerCase()=="m");     //false

if ((gender+"").toLowerCase()=="m") {
    System.out.println("if it went through loop");
}

Strange part is that you are using == for string comparison instead of equals method — Juned Ahsan, Jan 09 '14 at 11:48
System.out.println((gender+"").toLowerCase().equals("m")) should be used — Kamlesh Arya, Jan 09 '14 at 11:48
Or `if ((gender+"").toLowerCase().intern()=="m") { System.out.println("if it went through loop"); }` (I don't recommend it). — user2336315, Jan 09 '14 at 11:49

score 3 · Accepted Answer · answered Jan 09 '14 at 11:48

3

Use if ((gender+"").toLowerCase().equals("m")). You should not use == operator to compare the value of String. Use equals() method instead. Learn how the comparison of strings with equals and assignment operator

answered Jan 09 '14 at 11:48

Prasad Kharkar

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thanx, i am new to java just recently started – user3177212 Jan 09 '14 at 11:51
@user3177212 No issues :) I've made these mistakes too :). You'll get good info in the link. – Prasad Kharkar Jan 09 '14 at 11:52
oo i should have seen compare strings question i thought there was something wrong with toLowerCase, l'll delete the question – user3177212 Jan 09 '14 at 11:58
@user3177212. You don't have to delete the question. It can be useful for others. – Prasad Kharkar Jan 10 '14 at 03:25

toLowerCase() strange behaviour

1 Answers1