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Java Generics 问题:类型参数 E 不受其约束
原标题:Java Generics Question: type parameter E is not within its bound

i 先询问一般情况。 我完全没有这样做。 编辑告诉我:<代码>参数E不属于其约束范围。 我在理解汇编者错误方面通常没有问题,但这是一个很trick的问题。 也许我对一般知识的了解需要改进。 谁能告诉我什么错误?

public static <E extends Enum & StringConvertableEnum<E>> Map<String, E> map(Class<E> enumClass) {
    Map<String, E> mapping = new HashMap<String, E>();

    EnumSet<E> set = EnumSet.allOf(enumClass);

    for(E enumConstant : set) {
        mapping.put(enumConstant.getStringValue(), enumConstant);
    }

    return mapping;
}

这是<代码>的定义。 StringConvertableEnum:

public interface StringConvertableEnum<E extends Enum> {
    public E getEnumFromStringValue(String string);
    public String getStringValue();
}
问题回答

页: 1 Eext Enum<E>

我的全文是:

public static <E extends Enum<E> & StringConvertableEnum<E>> Map<String, E> map(Class<E> enumClass) {




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