Here you can find the source of isBasicType(Class> clazz)
public static boolean isBasicType(Class<?> clazz)
//package com.java2s; //License from project: Apache License import java.util.*; public class Main { public static boolean isBasicType(Class<?> clazz) { return !Collection.class.isAssignableFrom(clazz) && (clazz.equals(Integer.class) || clazz.equals(Integer.TYPE) || clazz.equals(Long.class) || clazz.equals(Long.TYPE) || clazz.equals(Boolean.class) || clazz.equals(Boolean.TYPE) || clazz.equals(Float.class) || clazz.equals(Float.TYPE) || clazz.equals(Double.class) || clazz.equals(Double.TYPE) || clazz.equals(Byte.class) || clazz.equals(Byte.TYPE) || clazz.equals(String.class) || Date.class .isAssignableFrom(clazz)); }// www .j a va2 s .c om }