java.lang
Class Class.MethodKey 
java.lang.Object
java.lang.Class.MethodKey
- Enclosing class:
- Class
- private static final class Class.MethodKey
- extends Object
|
Method Summary |
boolean |
equals(Object o)
Determine whether this Object is semantically equal
to another Object. |
int |
hashCode()
Get a value that represents this Object, as uniquely as
possible within the confines of an int. |
name
private String name
params
private Class[] params
returnType
private Class returnType
hash
private int hash
Class.MethodKey
Class.MethodKey(java.lang.reflect.Method m)
equals
public boolean equals(Object o)
- Description copied from class:
Object
- Determine whether this Object is semantically equal
to another Object.
There are some fairly strict requirements on this
method which subclasses must follow:
- It must be transitive. If
a.equals(b) and
b.equals(c), then a.equals(c)
must be true as well.
- It must be symmetric.
a.equals(b) and
b.equals(a) must have the same value.
- It must be reflexive.
a.equals(a) must
always be true.
- It must be consistent. Whichever value a.equals(b)
returns on the first invocation must be the value
returned on all later invocations.
a.equals(null) must be false.- It must be consistent with hashCode(). That is,
a.equals(b) must imply
a.hashCode() == b.hashCode().
The reverse is not true; two objects that are not
equal may have the same hashcode, but that has
the potential to harm hashing performance.
This is typically overridden to throw a ClassCastException
if the argument is not comparable to the class performing
the comparison, but that is not a requirement. It is legal
for a.equals(b) to be true even though
a.getClass() != b.getClass(). Also, it
is typical to never cause a NullPointerException.
In general, the Collections API (java.util) use the
equals method rather than the ==
operator to compare objects. However, java.util.IdentityHashMap
is an exception to this rule, for its own good reasons.
The default implementation returns this == o.
- Overrides:
equals in class Object
hashCode
public int hashCode()
- Description copied from class:
Object
- Get a value that represents this Object, as uniquely as
possible within the confines of an int.
There are some requirements on this method which
subclasses must follow:
- Semantic equality implies identical hashcodes. In other
words, if
a.equals(b) is true, then
a.hashCode() == b.hashCode() must be as well.
However, the reverse is not necessarily true, and two
objects may have the same hashcode without being equal.
- It must be consistent. Whichever value o.hashCode()
returns on the first invocation must be the value
returned on all later invocations as long as the object
exists. Notice, however, that the result of hashCode may
change between separate executions of a Virtual Machine,
because it is not invoked on the same object.
Notice that since hashCode is used in
java.util.Hashtable and other hashing classes,
a poor implementation will degrade the performance of hashing
(so don't blindly implement it as returning a constant!). Also,
if calculating the hash is time-consuming, a class may consider
caching the results.
The default implementation returns
System.identityHashCode(this)
- Overrides:
hashCode in class Object
JAVADOC |