Path: csiph.com!v102.xanadu-bbs.net!xanadu-bbs.net!news.glorb.com!news-out.readnews.com!transit4.readnews.com!news-out.news.tds.net!newsreading01.news.tds.net!53ab2750!not-for-mail From: "Eric Sosman" Subject: Re: default equals function? Message-ID: <50254C52.56583.calajapr@time.synchro.net> X-Comment-To: bob smith Newsgroups: comp.lang.java.programmer In-Reply-To: <50254C51.56582.calajapr@time.synchro.net> References: <50254C51.56582.calajapr@time.synchro.net> X-FTN-AREA: COMP.LANG.JAVA.PROGRAMMER X-FTN-MSGID: 1:261/38 192fccbb X-FTN-REPLY: 1:261/38 87f62330 Content-Type: text/plain; charset=IBM437 Content-Transfer-Encoding: 8bit X-Gateway: time.synchro.net [Synchronet 3.16a-Win32 NewsLink 1.98] Lines: 39 Date: Fri, 10 Aug 2012 18:39:03 GMT NNTP-Posting-Host: 69.21.70.65 X-Complaints-To: news@tds.net X-Trace: newsreading01.news.tds.net 1344623943 69.21.70.65 (Fri, 10 Aug 2012 13:39:03 CDT) NNTP-Posting-Date: Fri, 10 Aug 2012 13:39:03 CDT Organization: tds.net Xref: csiph.com comp.lang.java.programmer:17637 To: bob smith From: Eric Sosman On 8/9/2012 5:58 PM, bob smith wrote: > Let's say I have a class like this: > > public class Kern_Pair { > int letter1, letter2; > > } > > Can someone tell me how the default equals function will behave? > > like > > kernpair1.equals(kernpair2) > > ? Teachable Moment. The Kern_Pair class has no equals() method of its own, so it inherits equals() from the nearest superclass that has one. Walk up the class inheritance tree to find the nearest ancestor with an equals(). The class inheritance tree for Kern_Pair is fairly short: Its immediate superclass is Object (because you didn't say "extends SomethingElse"), so the equals() method for Kern_Pair *is* the equals() method of Object. Now all you need to do is go to the Javadoc and study what Object's equals() will do. -- Eric Sosman esosman@ieee-dot-org.invalid --- BBBS/Li6 v4.10 Dada-1 * Origin: Prism bbs (1:261/38) --- Synchronet 3.16a-Win32 NewsLink 1.98 Time Warp of the Future BBS - telnet://time.synchro.net:24