| public boolean equals(Object arg) Overrides java.lang.Object.equals.
Doc from java.lang.Object.equals.
Indicates whether some other object is "equal to" this one.
The equals method implements an equivalence relation
on non-null object references:
- It is reflexive: for any non-null reference value
x, x.equals(x) should return
true.
- It is symmetric: for any non-null 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 non-null 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 non-null reference values
x and y, multiple invocations of
x.equals(y) consistently return true
or consistently return false, provided no
information used in equals comparisons on the
objects is modified.
- For any non-null reference value
x,
x.equals(null) should return false.
An equivalence relation partitions the elements it operates on
into equivalence classes; all the members of an
equivalence class are equal to each other. Members of an
equivalence class are substitutable for each other, at least
for some purposes.
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