@SuppressWarnings("unchecked")
public static <T> T cast(Object obj, Class<T> clazz) throws Exception {
if (obj == null) {
return null;
}
TypeToken<T> type = TypeToken.of(clazz).wrap();
TypeToken<?> objType = TypeToken.of(obj.getClass()).wrap();
if (type.isAssignableFrom(objType)) {
return (T) obj;
}
if (TypeToken.of(List.class).isAssignableFrom(type) && objType.isArray()) {
List<Object> list = Arrays.asList((Object[]) obj);
return (T) list;
}
if (type.isArray() && TypeToken.of(List.class).isAssignableFrom(objType)) {
List<?> list = (List<?>) obj;
TypeToken<?> componentType = type.getComponentType();
Class<?> rawType;
if (componentType == null) {
rawType = Object.class;
} else {
rawType = componentType.getRawType();
}
Object[] array = (Object[]) Array.newInstance(rawType, list.size());
return (T) list.toArray(array);
}
if (clazz.isEnum()) {
return (T) Enum.valueOf((Class<? extends Enum>) clazz, obj.toString());
}
if (TypeToken.of(String.class).isAssignableFrom(type)) {
return (T) obj.toString();
}
if (TypeToken.of(Number.class).isAssignableFrom(type)) {
BigDecimal num = new BigDecimal(obj.toString());
if (TypeToken.of(Integer.class).isAssignableFrom(type)) {
return (T) Integer.valueOf(num.intValue());
}
if (TypeToken.of(Long.class).isAssignableFrom(type)) {
return (T) Long.valueOf(num.longValue());
}
if (TypeToken.of(Short.class).isAssignableFrom(type)) {
return (T) Short.valueOf(num.shortValue());
}
if (TypeToken.of(Byte.class).isAssignableFrom(type)) {
return (T) Byte.valueOf(num.byteValue());
}
if (TypeToken.of(Float.class).isAssignableFrom(type)) {
return (T) Float.valueOf(num.floatValue());
}
if (TypeToken.of(Double.class).isAssignableFrom(type)) {
return (T) Double.valueOf(num.doubleValue());
}
}
return null;
}
@Override
@SuppressWarnings("unchecked")
public boolean isValid(Object newValue) {
if (!type.isAssignableFrom(newValue.getClass())) return false;
return isValidValue((T) newValue);
}