Java Utililty Methods Reflection Generic Type from Class

List of utility methods to do Reflection Generic Type from Class

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Description

The list of methods to do Reflection Generic Type from Class are organized into topic(s).

Method

ClassgetGenericClass(final Class class1)
get Generic Class 
final Type type = class1.getGenericSuperclass();
return getGenericClass(type);
ClassgetGenericClass(final Class parametrizedClass, int pos)
get Generic Class 
final ParameterizedType pType = (ParameterizedType) parametrizedClass.getGenericSuperclass();
final TypeVariable tv = (TypeVariable) pType.getActualTypeArguments()[pos];
if (tv.getBounds()[0] instanceof ParameterizedType) {
    return (Class<T>) ((ParameterizedType) tv.getBounds()[0]).getRawType();
} else {
    return (Class<T>) tv.getBounds()[0];
ClassgetGenericClass(final Class parametrizedClass, int pos)
get Generic Class 
return (Class<T>) ((ParameterizedType) parametrizedClass.getGenericSuperclass())
        .getActualTypeArguments()[pos];
ClassgetGenericClass(final Method method)
get Generic Class 
final Type returnType = method.getGenericReturnType();
return getActualType(returnType, 0);
ClassgetGenericClass(Object o)
get Generic Class 
ParameterizedType parameterizedType = (ParameterizedType) o.getClass().getGenericSuperclass();
return (Class) parameterizedType.getActualTypeArguments()[0];
ClassgetGenericClass(Object object, int index)
get Generic Class 
ParameterizedType genericSuperclass = getParameterizedType(object.getClass());
if (genericSuperclass == null) {
    return String.class;
Class<?> rawType = getRawType(genericSuperclass.getActualTypeArguments()[index]);
if (rawType == null) {
    return String.class;
return rawType;
ClassgetGenericClass(Object source, ParameterizedType type)
Try to extract the generic type of the given ParameterizedType used in the given source object. 
Type type1 = type.getActualTypeArguments()[0];
if (type1 instanceof ParameterizedType) {
    return (Class) ((ParameterizedType) type1).getRawType();
} else if (type1 instanceof TypeVariable) {
    if (source.getClass().getGenericSuperclass() instanceof ParameterizedType) {
        return (Class) ((ParameterizedType) source.getClass().getGenericSuperclass())
                .getActualTypeArguments()[0];
    } else {
...
ClassgetGenericClass(Type type)
get Generic Class 
return getGenericClass(type, 0);
TypegetGenericClassByIndex(Type genericType, int index)
Get parameterized type 
Type clazz = null;
if (genericType instanceof ParameterizedType) {
    ParameterizedType t = (ParameterizedType) genericType;
    Type[] types = t.getActualTypeArguments();
    clazz = types[index];
return clazz;
TypegetGenericClassType(Class clazz, Class filterClass)
Extract the real Type from the passed class. 
for (Type type : clazz.getGenericInterfaces()) {
    if (type == filterClass) {
        return type;
    } else if (type instanceof ParameterizedType) {
        ParameterizedType pType = (ParameterizedType) type;
        if (filterClass.isAssignableFrom((Class) pType.getRawType())) {
            return type;
return null;