In a typical JVM, there are many String objects.  And among those String objects there are likely to be some with the same contents.  That is, with char[] values that hold the same characters.  If we could have equivalent char[] values point to just one instance of the char[], we could save the space occupied by the other copies.  This RFE covers an investigation of how much space could be saved, what benefit that would be, and possible alternatives for canonicalizing such char[]'s.