Bug ID: JDK-8223112 Clarify operational semantics of java.util.Objects.equals()

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JDK 13
13 b20Fixed

ADDITIONAL SYSTEM INFORMATION :
not OS / runtime specific issue.

A DESCRIPTION OF THE PROBLEM :
In Objects.equals(myObject1, myObject2), if myObject2 is null and if myObject1.equals() doesn't handle null check, nullPointerException will be thrown. 

JavaDoc says, false will be returned if either of the parameter is null but it is not handled for second parameter.


FREQUENCY : always

URL: http://hg.openjdk.java.net/jdk/jdk/rev/90855d9c3c39 User: darcy Date: 2019-05-03 16:26:09 +0000
03-05-2019
Exact implementation used for Objects.equals discussed in review thread: http://mail.openjdk.java.net/pipermail/core-libs-dev/2009-September/002580.html
02-05-2019
Review thread: http://mail.openjdk.java.net/pipermail/core-libs-dev/2019-May/060000.html
02-05-2019
The assumption is that every implementation of equals(null) should be handled by the class itself.
30-04-2019
As per the documentation at https://docs.oracle.com/en/java/javase/12/docs/api/java.base/java/util/Objects.html#equals(java.lang.Object,java.lang.Object) : "if exactly one argument is null, false is returned. " As per the implementation, if the first argument is null , it will return false otherwise it is delegated to the equals() method of the first argument .The result is then dependent on whether the equals() method of the first argument follows the contract properly or not. As such the documentation should not guarantee that if any of the arguments is null, false will be returned .
30-04-2019

CSR :	JDK-8223265 - Clarify operational semantics of java.util.Objects.equals()
Duplicate :	JDK-8196069 - Misleading documentation of Objects.equals
Relates :	JDK-6797535 - Add shared two argument static equals method to the platform
Relates :	JDK-8283762 - Modify if (e1 == null) to if (e1 == null \|\| e2 == null) in "deepEquals" method of Arrays.java
Relates :	JDK-8196069 - Misleading documentation of Objects.equals