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abstract public class: Enum [javadoc | source]

All Implemented Interfaces:
    Comparable, java$io$Serializable

This is the common base class of all Java language enumeration types. More information about enums, including descriptions of the implicitly declared methods synthesized by the compiler, can be found in section 8.9 of The Java™ Language Specification.

Note that when using an enumeration type as the type of a set or as the type of the keys in a map, specialized and efficient {@linkplain java.util.EnumSet set} and {@linkplain java.util.EnumMap map} implementations are available.

 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.
    name - - The name of this enum constant, which is the identifier used to declare it.
    ordinal - - The ordinal of this enumeration constant (its position in the enum declaration, where the initial constant is assigned an ordinal of zero).
Method from java.lang.Enum Summary:
clone,   compareTo,   equals,   finalize,   getDeclaringClass,   hashCode,   name,   ordinal,   toString,   valueOf
Methods from java.lang.Object:
clone,   equals,   finalize,   getClass,   hashCode,   notify,   notifyAll,   toString,   wait,   wait,   wait
Method from java.lang.Enum Detail:
 protected final Object clone() throws CloneNotSupportedException 
    Throws CloneNotSupportedException. This guarantees that enums are never cloned, which is necessary to preserve their "singleton" status.
 public final int compareTo(E o) 
    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.
 protected final  void finalize() 
    enum classes cannot have finalize methods.
 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 Object#getClass method for enum constants with constant-specific class bodies.)
 public final int hashCode() 
    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.
 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 .
 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.
 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.)

    Note that for a particular enum type {@code T}, the implicitly declared {@code public static T valueOf(String)} method on that enum may be used instead of this method to map from a name to the corresponding enum constant. All the constants of an enum type can be obtained by calling the implicit {@code public static T[] values()} method of that type.