Here you can find the source of isComposite(Class> cls)
public static boolean isComposite(Class<?> cls)
//package com.java2s; //License from project: Open Source License import java.util.*; public class Main { public static boolean isComposite(Class<?> cls) { return isArray(cls) || isCollection(cls); }/* w ww . j a v a2s.c om*/ public static <T> boolean isArray(Class<T> cls) { return cls.isArray(); } public static <T> boolean isCollection(Class<T> cls) { return Collection.class.isAssignableFrom(cls); } }