Apache 枚举工具类的源码的分析

Apache commons-lang报的枚举工具类的学习应用：

他提供的根据枚举的类方法如下逐个分析

备注咋Apache commons-lang中枚举对象（Enum是一个封装枚举类而非枚举类型）

 

public class EnumUtils {

    /**
     * Public constructor. This class should not normally be instantiated.
     * @since 2.0
     */
    public EnumUtils() {
      super();
    }

    /**

    * 根据枚举类和类型类型的名称（value）查找枚举
     * <p>Gets an <code>Enum</code> object by class and name.</p>
     *
     * @param enumClass  the class of the <code>Enum</code> to get
     * @param name  the name of the Enum to get, may be <code>null</code>
     * @return the enum object
     * @throws IllegalArgumentException if the enum class is <code>null</code>
     */
    public static Enum getEnum(Class enumClass, String name) {
        return Enum.getEnum(enumClass, name);
    }

    /**根据枚举类和枚举键查找
     * <p>Gets a <code>ValuedEnum</code> object by class and value.</p>
     *
     * @param enumClass  the class of the <code>Enum</code> to get
     * @param value  the value of the <code>Enum</code> to get
     * @return the enum object, or null if the enum does not exist
     * @throws IllegalArgumentException if the enum class is <code>null</code>
     */
    public static ValuedEnum getEnum(Class enumClass, int value) {
        return (ValuedEnum) ValuedEnum.getEnum(enumClass, value);
    }

    /**根据枚举类查找所有枚举类型的Map
     * <p>Gets the <code>Map</code> of <code>Enum</code> objects by
     * name using the <code>Enum</code> class.</p>
     *
     * <p>If the requested class has no enum objects an empty
     * <code>Map</code> is returned. The <code>Map</code> is unmodifiable.</p>
     *
     * @param enumClass  the class of the <code>Enum</code> to get
     * @return the enum object Map
     * @throws IllegalArgumentException if the enum class is <code>null</code>
     * @throws IllegalArgumentException if the enum class is not a subclass
     *  of <code>Enum</code>
     */
    public static Map getEnumMap(Class enumClass) {
        return Enum.getEnumMap(enumClass);
    }

    /**根据枚举类所有枚举类型集合
     * <p>Gets the <code>List</code> of <code>Enum</code> objects using
     * the <code>Enum</code> class.</p>
     *
     * <p>The list is in the order that the objects were created
     * (source code order).</p>
     *
     * <p>If the requested class has no enum objects an empty
     * <code>List</code> is returned. The <code>List</code> is unmodifiable.</p>
     *
     * @param enumClass  the class of the Enum to get
     * @return the enum object Map
     * @throws IllegalArgumentException if the enum class is <code>null</code>
     * @throws IllegalArgumentException if the enum class is not a subclass
     *  of <code>Enum</code>
     */
    public static List getEnumList(Class enumClass) {
        return Enum.getEnumList(enumClass);
    }

    /**
     * <p>Gets an <code>Iterator</code> over the <code>Enum</code> objects
     * in an <code>Enum</code> class.</p>
     *
     * <p>The iterator is in the order that the objects were created
     * (source code order).</p>
     *
     * <p>If the requested class has no enum objects an empty
     * <code>Iterator</code> is returned. The <code>Iterator</code>
     * is unmodifiable.</p>
     *
     * @param enumClass  the class of the <code>Enum</code> to get
     * @return an <code>Iterator</code> of the <code>Enum</code> objects
     * @throws IllegalArgumentException if the enum class is <code>null</code>
     * @throws IllegalArgumentException if the enum class is not a subclass of <code>Enum</code>
     */
    public static Iterator iterator(Class enumClass) {
        return Enum.getEnumList(enumClass).iterator();
    }
   
}