java反射调用实例代码

package com.test.refelect; import java.io.ObjectInputStream.GetField; import java.lang.reflect.Constructor; import java.lang.reflect.Field; import java.lang.reflect.InvocationTargetException; import java.lang.reflect.Method; public class TestRefelect { public static void main(String[] args) throws Exception { Class clazz = Class.forName("com.test.refelect.People"); // Class clazz = new People().getClass(); // Class clazz = People.class; People people = (People) clazz.newInstance(); Method method = clazz.getDeclaredMethod("say",null);//得到私有的方法 //需要设置accessible为true否则会抛出 //can not access a member of class com.test.refelect.People with modifiers "private" // method.setAccessible(true); // method.invoke(people, null); //----------------------------------------------- @SuppressWarnings("unchecked") // Method method = clazz.getMethod("setName",String.class);//由于setName是公有的方法，所以这里调用getMethod方法 // method.invoke(people,(Object)(new String("小明"))); // System.out.println(people.getName()); // //------------------------------------------------ // method = clazz.getDeclaredMethod("say",null); // method.setAccessible(true); // method.invoke(people, null); // //--------------------------------------------- // Constructor constructor = clazz.getConstructor(String.class,int.class,String[].class);//这里需要传入参数的类型 // //这里需要将所有的参数转换成Object类型 // People people2 = (People) constructor.newInstance(new Object[]{"xiaoming",22,new String[]{"china","shanxi","xi'an"}}); // // System.out.println(people2.getName()+people2.getAge()+people2.getAddress()[0]+people2.getAddress()[1]+people2.getAddress()[2]); // //-------------------------------------------- // Field field = clazz.getDeclaredField("testChangeString"); // field.setAccessible(true); // // field.set(people,field.get(people).toString().replace('a','b')); // System.out.println(field.get(people).toString()); // // //----------------------------------------------- Field fruitField = clazz.getDeclaredField("fruit"); fruitField.setAccessible(true); fruitField.set(people,"apple"); System.out.println(fruitField.get(people)); method = clazz.getMethod("setFruit",String.class); method.invoke(people,"banbanba"); System.out.println(clazz.getMethod("getFruit",null).invoke(people, null)); method = clazz.getDeclaredMethod("say",null); method.setAccessible(true); method.invoke(people,null); // // // //-------------------------------------------------------- // // method = clazz.getDeclaredMethod("test",String.class,int.class); // method.setAccessible(true); // method.invoke(people, new Object[]{"testsdf",22}); } }