Types.java 文件源码

public static Class<?> getRawType(Type type) {
  if (type instanceof Class<?>) {
    // type is a normal class.
    return (Class<?>) type;

  } else if (type instanceof ParameterizedType) {
    ParameterizedType parameterizedType = (ParameterizedType) type;

    // I'm not exactly sure why getRawType() returns Type instead of Class. Neal isn't either but
    // suspects some pathological case related to nested classes exists.
    Type rawType = parameterizedType.getRawType();
    return (Class<?>) rawType;

  } else if (type instanceof GenericArrayType) {
    Type componentType = ((GenericArrayType) type).getGenericComponentType();
    return Array.newInstance(getRawType(componentType), 0).getClass();

  } else if (type instanceof TypeVariable) {
    // We could use the variable's bounds, but that won't work if there are multiple. having a raw
    // type that's more general than necessary is okay.
    return Object.class;

  } else if (type instanceof WildcardType) {
    return getRawType(((WildcardType) type).getUpperBounds()[0]);

  } else {
    String className = type == null ? "null" : type.getClass().getName();
    throw new IllegalArgumentException("Expected a Class, ParameterizedType, or "
        + "GenericArrayType, but <" + type + "> is of type " + className);
  }
}