| java.lang.Object | |
| ↳ | java.lang.Enum<E extends java.lang.Enum<E>> |
 Known Direct Subclasses
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Class Overview
This is the common base class of all Java language enumeration types.
Summary
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Enum(String name, int ordinal)
Sole constructor.
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| Public Methods | |||||||||||
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| final int |
compareTo(E e)
Compares this enum with the specified object for order.
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| final boolean |
equals(Object other)
Returns true if the specified object is equal to this enum constant.
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| final Class<E> |
getDeclaringClass()
Returns the Class object corresponding to this enum constant's enum type.
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| final int |
hashCode()
Returns a hash code for this enum constant.
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| final String |
name()
Returns the name of this enum constant, exactly as declared in its enum
declaration.
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| final int |
ordinal()
Returns the ordinal of this enumeration constant (its position in its enum
declaration, where the initial constant is assigned an ordinal of zero).
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| String |
toString()
Returns the name of this enum constant, as contained in the declaration.
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| static <T extends Enum<T>> T |
valueOf(Class<T> enumType, String name)
Returns the enum constant of the specified enum type with the specified name.
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| Protected Methods | |||||||||||
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| Object |
clone()
Throws CloneNotSupportedException.
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[Expand]
Inherited Methods | |||||||||||
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From class
java.lang.Object
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From interface
java.lang.Comparable
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Protected Constructors
protected Enum (String name, int ordinal)
Sole constructor. Programmers cannot invoke this constructor. It is for use by code emitted by the compiler in response to enum type declarations.
Parameters
| name | the name of this enum constant, which is the identifier used to declare it. |
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| ordinal | the ordinal of this enumeration constant (its position in the enum declaration, where the initial constant is assigned an ordinal of zero). |
Public Methods
public final int compareTo (E e)
Compares this enum with the specified object for order. Returns a negative integer, zero, or a positive integer as this object is less than, equal to, or greater than the specified object. Enum constants are only comparable to other enum constants of the same enum type. The natural order implemented by this method is the order in which the constants are declared.
public final boolean equals (Object other)
Returns true if the specified object is equal to this enum constant.
Parameters
| other | the object to be compared for equality with this object. |
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Returns
- true if the specified object is equal to this enum constant.
public final Class<E> getDeclaringClass ()
Returns the Class object corresponding to this enum constant's enum type. Two
enum constants e1 and e2 are of the same enum type if and only if
e1.getDeclaringClass() == e2.getDeclaringClass(). (The value returned by this
method may differ from the one returned by the getClass() method
for enum constants with constant-specific class bodies.)
Returns
- the
Classobject corresponding to this enum constant's enum type
public final int hashCode ()
Returns a hash code for this enum constant.
Returns
- a hash code for this enum constant.
public final String name ()
Returns the name of this enum constant, exactly as declared in its enum
declaration.
Most programmers should use the toString() method in preference to
this one, as the toString method may return a more user-friendly name.
This method is designed primarily for use in specialized situations where
correctness depends on getting the exact name, which will not vary from
release to release.
Returns
- the name of this enum constant
public final int ordinal ()
Returns the ordinal of this enumeration constant (its position in its enum declaration, where the initial constant is assigned an ordinal of zero). Most programmers will have no use for this method. It is designed for use by sophisticated enum-based data structures, such as java.util.EnumSet and java.util.EnumMap.
Returns
- the ordinal of this enumeration constant
public String toString ()
Returns the name of this enum constant, as contained in the declaration. This method may be overridden, though it typically isn't necessary or desirable. An enum type should override this method when a more "programmer-friendly" string form exists.
Returns
- the name of this enum constant
public static T valueOf (Class<T> enumType, String name)
Returns the enum constant of the specified enum type with the specified name. The name must match exactly an identifier used to declare an enum constant in this type. (Extraneous whitespace characters are not permitted.)
Parameters
| enumType | the Class object of the enum type from which to return a
constant |
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| name | the name of the constant to return |
Returns
- the enum constant of the specified enum type with the specified name
Throws
| IllegalArgumentException | if the specified enum type has no constant with the specified name, or the specified class object does not represent an enum type |
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| NullPointerException | if enumType or name is null |
Protected Methods
protected Object clone ()
Throws CloneNotSupportedException. This guarantees that enums are never cloned, which is necessary to preserve their "singleton" status.
Returns
- (never returns)
Throws
| CloneNotSupportedException |
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