Reflection——利用反射调用构造函数和私有字段

TwoString.java

 

public class TwoString {private String m_s1, m_s2;public String getM_s1() {return m_s1;}public void setM_s1(String m_s1) {this.m_s1 = m_s1;}public String getM_s2() {return m_s2;}public void setM_s2(String m_s2) {this.m_s2 = m_s2;}public TwoString(String s1, String s2) {m_s1 = s1;m_s2 = s2;}}

 

 

ReflectConstructor.java

 

import java.lang.reflect.*;public class ReflectConstructor {public static void main(String[] args) throws Exception {Class[] types = new Class[] { String.class, String.class };Constructor<TwoString> cons = TwoString.class.getConstructor(types);Object[] args1 = new Object[] { "a", "b" };TwoString ts = cons.newInstance(args1);Field field = TwoString.class.getDeclaredField("m_s1");field.setAccessible(true);System.out.println(field.get(ts));}}