Object.equals
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public boolean equals( Object obj )
Parameters
- obj
- the reference object with which to compare.
Returns
true if this object is the same as the obj
argument; false otherwise.
Description
Compares two Objects for equality.
The equals method implements an equivalence relation:
- It is reflexive: for any reference value x,
x.equals(x) should return true.
- It is symmetric: for any reference values x and
y, x.equals(y) should return
true if and only if y.equals(x) returns
true.
- It is transitive: for any reference values x,
y, and z, if x.equals(y)
returns true and y.equals(z) returns
true, then x.equals(z) should return
true.
- It is consistent: for any reference values x
and y, multiple invocations of x.equals(y)
consistently return true or consistently return
false.
- For any reference value x, x.equals(null)
should return false.
The equals method for class Object implements the most
discriminating possible equivalence relation on objects; that is,
for any reference values x and y, this
method returns true if and only if x and
y refer to the same object (x==y has the
value true).
See Also
hashCode, Hashtable