Just Java™ 2

String Comparison

Just a reminder about String comparisons. Compare two Strings like this:

if ( s1.equals(s2) )

not like this:

if (s1 == s2)

The first compares string contents, the second, string addresses (this is another artifact of reference types, remember?). Failing to use equals() to compare two strings is probably the most common single mistake made by Java novices.

Tip: Using intern() on Strings

There is one exception to rule of comparing Strings by calling equals(). The exception has been put in place as a performance optimization. String has a method called intern(). You can call intern() on one of your strings, to put it into ...