Package eu.simuline.util
Class SoftEnum<E extends SoftEnum<E>>
- java.lang.Object
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- eu.simuline.util.SoftEnum<E>
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- Type Parameters:
E- The enum type subclass
- All Implemented Interfaces:
Serializable,Comparable<E>
public abstract class SoftEnum<E extends SoftEnum<E>> extends Object implements Comparable<E>, Serializable
This class is inspired byEnumand is intended as common base class of classes we shall call 'soft enums'. While soft enums are ordinary classes and lack all support special to enumeration types, they are also not subject to the restrictions that come with them.It is the programmer who is responsible for implementing soft enums in a proper way.
As enumeration types are implicitely final subclasses of
Enum, 'soft enums' are derived fromSoftEnumand shall be final except if constants overwrite methods. A 'soft enum' shall have no instances other than those defined by its enum constants. 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 set and map implementations are available.
- Since:
- 1.5
- Author:
- Josh Bloch, Neal Gafter
- See Also:
Class.getEnumConstants(),EnumSet,EnumMap, Serialized Form
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Field Summary
Fields Modifier and Type Field Description private StringnameThe name of this enum constant, as declared in the enum declaration.private intordinalThe ordinal of this enumeration constant (its position in the enum declaration, where the initial constant is assigned an ordinal of zero).private static longserialVersionUID
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Method Summary
All Methods Instance Methods Concrete Methods Modifier and Type Method Description SoftEnum<E>clone()Throws CloneNotSupportedException.intcompareTo(E obj)Compares this enum with the specified object for order.booleanequals(Object other)Returns true if the specified object is equal to this enum constant.Class<?>getDeclaringClass()Returns the Class object corresponding to this enum constant's enum type.inthashCode()Returns a hash code for this enum constant.Stringname()Returns the name of this enum constant, exactly as declared in its enum declaration.intordinal()Returns the ordinal of this enumeration constant (its position in its enum declaration, where the initial constant is assigned an ordinal of zero).private voidreadObject(ObjectInputStream stream)Prevent default deserialization.private voidreadObjectNoData()StringtoString()Returns the name of this enum constant, as contained in the declaration.
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Field Detail
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serialVersionUID
private static final long serialVersionUID
- See Also:
- Constant Field Values
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name
private final String name
The name of this enum constant, as declared in the enum declaration. Most programmers should use thetoString()method rather than accessing this field.
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ordinal
private final int ordinal
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Constructor Detail
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SoftEnum
protected SoftEnum(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.ordinal- - The ordinal of this enumeration constant (its position in the enum declaration, where the initial constant is assigned an ordinal of zero).
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Method Detail
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name
public final String name()
Returns the name of this enum constant, exactly as declared in its enum declaration. Most programmers should use thetoString()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
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ordinal
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 asEnumSetandEnumMap.- Returns:
- the ordinal of this enumeration constant
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toString
public final 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.
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equals
public final boolean equals(Object other)
Returns true if the specified object is equal to this enum constant.
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hashCode
public final int hashCode()
Returns a hash code for this enum constant.
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clone
public final SoftEnum<E> clone() throws CloneNotSupportedException
Throws CloneNotSupportedException. This guarantees that enums are never cloned, which is necessary to preserve their "singleton" status.- Overrides:
clonein classObject- Returns:
- (never returns)
- Throws:
CloneNotSupportedException
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compareTo
public final int compareTo(E obj)
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.- Specified by:
compareToin interfaceComparable<E extends SoftEnum<E>>
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getDeclaringClass
public final Class<?> 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 theObject.getClass()method for enum constants with constant-specific class bodies.)- Returns:
- the Class object corresponding to this enum constant's enum type
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readObject
private void readObject(ObjectInputStream stream) throws IOException, ClassNotFoundException
Prevent default deserialization.- Throws:
IOExceptionClassNotFoundException
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readObjectNoData
private void readObjectNoData() throws ObjectStreamException- Throws:
ObjectStreamException
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