1 import java.lang.reflect.Constructor; 2 import java.lang.reflect.InvocationTargetException; 3 import java.util.ArrayList; 4 import java.util.List; 5  6 import org.junit.Test; 7  8 public class Demo { 9 10     /**11      * 反射类的构造函数，创建类的对象12      * 13      * @param args14      * @throws ClassNotFoundException15      * @throws Exception16      * @throws IllegalAccessException17      * @throws InstantiationException18      * @throws IllegalArgumentException19      */20 21     // 反射构造函数：public Person()22     @Test23     public void test1() throws Exception {24 25         Class clazz = Class.forName("Person");26 27         Constructor c = clazz.getConstructor(null);28 29         Person p = (Person) c.newInstance(null);30 31         System.out.println(p.name);32 33     }34 35     // 反射构造函数：public Person(String name);36     @Test37     public void test2() throws Exception {38         Class clazz = Class.forName("Person");39 40         Constructor c = clazz.getConstructor(String.class);41 42         Person p = (Person) c.newInstance("xxxxx");43         44         System.out.println(p.name);45 46     }47     48     //public Person(String name,int password){}49     @Test50     public void test3() throws Exception {51         Class clazz = Class.forName("Person");52 53         Constructor c = clazz.getConstructor(String.class,int.class);54 55         Person p = (Person) c.newInstance("xxxxx",12);56         57         System.out.println(p.name);58 59     }60     61     //public Person(List list){}62     @Test63     public void test4() throws Exception {64         Class clazz = Class.forName("Person");65 66         Constructor c = clazz.getDeclaredConstructor(List.class);67         68         c.setAccessible(true);//暴力反射，设置可以访问私有69         70         Person p = (Person) c.newInstance(new ArrayList());71         72         System.out.println(p.name);73 74     }75     76     //创建对象的另一种方法77     @Test78     public void test5() throws Exception {79         Class clazz = Class.forName("Person");80       81         Person p = (Person) clazz.newInstance();82         83         System.out.println(p.name);84 85     }86 }

 1 import java.util.List; 2  3  4 public class Person { 5      6     public String name="hellowrold"; 7  8     public Person(){ 9         System.out.println("person");10     }11     12     public Person(String name){13         System.out.println("person :"+name);14     }15     16     public Person(String name,int password){17         System.out.println("person:"+name+password);18     }19     20     private Person(List list){21         System.out.println("list");22     }23 }