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| From | Alex J <vstrength@gmail.com> |
| Newsgroups | comp.lang.java.programmer |
| Subject | The behavior of "equals" method of Arrays.asList() implementation |
| Date | Tue, 28 Jun 2011 02:19:02 -0700 (PDT) |
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Basically I wonder if it is safe to use equals for collections (and junit's assertEquals in particular which in fact results in the *.equals invocation). One of collection instances I am working with is returned from Arrays.asList(..) method invocation. Sun JDK sources defines no equals method for java.util.Arrays.ArrayList inner class so I guess it is not safe to compare collections in that way. Surprisingly, equals called from Arrays.ArrayList "magically" (I can't find another word) checks the elements in the collection! I tried to walk throug the sources by using "step into" in the debugger, but it mysteriously transfer control to the equals method of my class (and yes, I have JDK sources attached, e.g. I can walk through implementation of certain String method). So the first question is: whether it is safe to use equals for *all* the JDK's collections? The second question is whether JVM adds "hidden" implementation in certain places and Arrays helper List implementation is one of those, so I may expect Arrays.asList(...) implementation behave in the same way on different JDKs? Thanks in advance!
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The behavior of "equals" method of Arrays.asList() implementation Alex J <vstrength@gmail.com> - 2011-06-28 02:19 -0700
Re: The behavior of "equals" method of Arrays.asList() implementation Eric Sosman <esosman@ieee-dot-org.invalid> - 2011-06-28 07:08 -0400
Re: The behavior of "equals" method of Arrays.asList() implementation Lew <noone@lewscanon.com> - 2011-06-28 07:29 -0400
Re: The behavior of "equals" method of Arrays.asList() implementation Roedy Green <see_website@mindprod.com.invalid> - 2011-06-28 10:04 -0700
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