com.google.common.base

Class Enums

java.lang.Object

com.google.common.base.Enums

@GwtCompatible(emulated=true)
@Beta
public final class Enums
extends java.lang.Object

Utility methods for working with Enum instances.

Since:

9.0

Author:

Steve McKay

Method Summary

Methods

Modifier and Type	Method and Description
static java.lang.reflect.Field	getField(java.lang.Enum<?> enumValue) Returns the Field in which enumValue is defined.
static <T extends java.lang.Enum<T>> Optional<T>	getIfPresent(java.lang.Class<T> enumClass, java.lang.String value) Returns an optional enum constant for the given type, using Enum.valueOf(java.lang.Class<T>, java.lang.String).
static <T extends java.lang.Enum<T>> Function<java.lang.String,T>	valueOfFunction(java.lang.Class<T> enumClass) Returns a Function that maps an Enum name to the associated Enum constant.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

getField

@GwtIncompatible(value="reflection")
public static java.lang.reflect.Field getField(java.lang.Enum<?> enumValue)

Returns the Field in which enumValue is defined. For example, to get the Description annotation on the GOLF constant of enum Sport, use Enums.getField(Sport.GOLF).getAnnotation(Description.class).

Since:

12.0

valueOfFunction

public static <T extends java.lang.Enum<T>> Function<java.lang.String,T> valueOfFunction(java.lang.Class<T> enumClass)

Returns a Function that maps an Enum name to the associated Enum constant. The Function will return null if the Enum constant does not exist.

Parameters:

enumClass - the Class of the Enum declaring the constant values.

getIfPresent

public static <T extends java.lang.Enum<T>> Optional<T> getIfPresent(java.lang.Class<T> enumClass,
                                                     java.lang.String value)

Returns an optional enum constant for the given type, using Enum.valueOf(java.lang.Class<T>, java.lang.String). If the constant does not exist, Optional.absent() is returned. A common use case is for parsing user input or falling back to a default enum constant. For example, Enums.getIfPresent(Country.class, countryInput).or(Country.DEFAULT);

Since:

12.0