rspec/rules/S1157/java/rule.adoc

== Why is this an issue?

Using `toLowerCase()` or `toUpperCase()` to make case insensitive comparisons is inefficient because it requires the creation of temporary, intermediate `String` objects.


=== Noncompliant code example

[source,java,diff-id=1,diff-type=noncompliant]
----
private void compareStrings(String foo, String bar){
    boolean result1 = foo.toUpperCase().equals(bar);               // Noncompliant
    boolean result2 = foo.equals(bar.toUpperCase());               // Noncompliant
    boolean result3 = foo.toLowerCase().equals(bar.toLowerCase()); // Noncompliant
}
----


=== Compliant solution

[source,java,diff-id=1,diff-type=compliant]
----
private void compareStrings(String foo, String bar){
    boolean result1 = foo.equalsIgnoreCase(bar);                    // Compliant
}
----


=== Exceptions

No issue will be raised when a locale is specified because the result could be different from `equalsIgnoreCase()`. (e.g.: using the Turkish locale)

[source,java]
----
private void compareStrings(String foo, String bar, java.util.Locale locale){
    boolean result1 = foo.toUpperCase(locale).equals(bar);         // Compliant
}
----


ifdef::env-github,rspecator-view[]

'''
== Implementation Specification
(visible only on this page)

=== Message

Replace "[toUpperCase()|toLowerCase()]" and "equals()" calls with a single call to "equalsIgnoreCase()".


'''
== Comments And Links
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=== on 29 Jul 2013, 14:10:11 Dinesh Bolkensteyn wrote:
This one is interesting, I made the mistake a few times I think ;-)

=== on 29 Jul 2013, 14:10:24 Dinesh Bolkensteyn wrote:
Implemented by \http://jira.codehaus.org/browse/SONARJAVA-245

=== on 29 Jul 2013, 23:56:51 Ann Campbell wrote:
Dinesh went a lot of rounds on this one. It'll probably kill him that I still made a change.

=== on 30 Jul 2013, 08:21:27 Dinesh Bolkensteyn wrote:
Not at all Ann ;-) I didn't yet commit the implementation, so your change did not take any additional effort to apply! Thanks!

=== on 31 Jul 2013, 00:10:00 Ann Campbell wrote:
Sorry Dinesh, but I missed a spot yesterday. :-(

=== on 7 Aug 2013, 05:52:30 Dinesh Bolkensteyn wrote:
Thanks, I've just applied your changes!

endif::env-github,rspecator-view[]