注意:int.class不等于Integer.class 问题:因此此处调用Person p = createPerson(Person.class,3,"nilu");会找不到对应构造函数,因为它找的是传入Integer与String的构造函数,如何解决?//junit测试函数@Testpublic void test() throws ClassNotFoundException, SecurityException, NoSuchMethodException, IllegalArgumentException, InstantiationException, IllegalAccessException, InvocationTargetException {Person p = createPerson(Person.class,3,"nilu");p.eat();}public <T> T createPerson(Class<T> clazz, Object ...args) throws SecurityException, NoSuchMethodException, IllegalArgumentException, InstantiationException, IllegalAccessException, InvocationTargetException {final List<Class> list = new ArrayList<Class>();for(Object obj : args) {list.add(obj.getClass());}Class []_args = new Class[args.length];list.toArray(_args);list.clear();Constructor<T> constructor = clazz.getConstructor(_args);T t = constructor.newInstance(args);return t;}类:public class Person {private String name;private int age;public Person() {this.age = 18;this.name = "default name";System.out.println("Person constructor");}public Person(String name) {this.name = name;System.out.println("Person name : " + name);}public Person(int age, String name) {this.age = age;this.name = name;System.out.println("Person name : " + name);System.out.println("Person age : " + age);}}=======================================================================问题描述补充:Constructor<T> constructor = clazz.getConstructor(_args);这一行 根据_args是哪些.class 会决定得到哪个构造函数,这里实际得到的是Integer.class与String.class;然而Person(int age, String name)实际要的是int.class与String.class;这是由于调用createPerson时候,3这个int被自动装箱了,变成了Integer,因此程序会报错提示味找到构造函数createPerson(Integer,String)
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