java.lang
public abstract class Enum<T extends Enum<T>> extends Object implements Comparable<T>, Serializable
Modifier | Constructor and Description |
---|---|
protected |
Enum(String name,
int ordinal)
This constructor is used by the compiler to create enumeration constants.
|
Modifier and Type | Method and Description |
---|---|
protected Object |
clone()
Cloning of enumeration constants is prevented, to maintain their
singleton status.
|
int |
compareTo(T e)
Returns an integer which represents the relative ordering of this
enumeration constant.
|
boolean |
equals(Object o)
Returns true if this enumeration is equivalent to the supplied object,
o . |
protected void |
finalize()
Enumerations can not have finalization methods.
|
Class<T> |
getDeclaringClass()
Returns the type of this enumeration constant.
|
int |
hashCode()
Returns the hash code of this constant.
|
String |
name()
Returns the name of this enumeration constant.
|
int |
ordinal()
Returns the number of this enumeration constant, which represents
the order in which it was originally declared, starting from zero.
|
String |
toString()
Returns a textual representation of this enumeration constant.
|
static <S extends Enum<S>> |
valueOf(Class<S> etype,
String s)
Returns an Enum for a enum class given a description string of
the enum constant.
|
public static <S extends Enum<S>> S valueOf(Class<S> etype, String s)
NullPointerException
- when etype or s are null.IllegalArgumentException
- when there is no value s in
the enum etype.public final boolean equals(Object o)
o
. Only one instance of an enumeration constant exists,
so the comparison is simply done using ==
.equals
in class Object
o
- the object to compare to this.this == o
.Object.hashCode()
public final int hashCode()
hashCode
in class Object
Object.equals(Object)
,
System.identityHashCode(Object)
public String toString()
toString
in class Object
Object.getClass()
,
Object.hashCode()
,
Class.getName()
,
Integer.toHexString(int)
public final int compareTo(T e)
compareTo
in interface Comparable<T extends Enum<T>>
e
- the enumeration constant to compare.e.ordinal < this.ordinal
,
zero if e.ordinal == this.ordinal
and a positive
integer if e.ordinal > this.ordinal
.ClassCastException
- if e
is not an enumeration
constant of the same class.protected final Object clone() throws CloneNotSupportedException
clone
in class Object
CloneNotSupportedException
- as enumeration constants can't be
cloned.Cloneable
public final String name()
public final int ordinal()
public final Class<T> getDeclaringClass()
protected final void finalize()
finalize
in class Object
System.gc()
,
System.runFinalizersOnExit(boolean)
,
java.lang.ref