Comparing two strings within if statement

Question

I have the following code:

String tmp = "cif";
String control = tmp.substring(1);


if(control == "if") {

append = "if( ";

}

However, despite control being "if", the test will still fail. Any solutions?

check this out http://stackoverflow.com/questions/513832/how-do-i-compare-strings-in-java — William Kinaan, Apr 13 '13 at 20:42

score 5 · Answer 1 · answered Apr 13 '13 at 20:40

5

== compares object references whereas .equals() compares actual value

if(control.equals("if") {
   append = "if( ";
}

answered Apr 13 '13 at 20:40

Adil Shaikh

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score 2 · Answer 2 · answered Apr 13 '13 at 20:40

2

For string compare use equals()

answered Apr 13 '13 at 20:40

Joan

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score 2 · Answer 3 · edited Apr 13 '13 at 20:43

2

The "==" operator will compare the memory address of two strings, not their values. You need to use equals(). In your case, do something like "if".equals(control);.

edited Apr 13 '13 at 20:43

Vitaly

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answered Apr 13 '13 at 20:41

kronion

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score 1 · Answer 4 · answered Apr 13 '13 at 20:51

1

String tmp = "cif";
String control = tmp.substring(1);

if(control.equals("if")) {
   append = "if( ";
}

answered Apr 13 '13 at 20:51

gkiko

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score 0 · Answer 5 · edited Apr 13 '13 at 20:48

0

You cannot compare Strings via the == operator as Strings are objects.

Being objects, it does give the extra functionality of them having various methods inside of their classes. One such method which may come in handy is the equals() method.

The code you will therefore want would be:

String tmp = "cif";
String control = tmp.substring(1);

if("if".equals(control) {

...

edited Apr 13 '13 at 20:48

Vitaly

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answered Apr 13 '13 at 20:43

Mike

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Comparing two strings within if statement

5 Answers5