import java.lang.reflect.Constructor;
import java.lang.reflect.Field;
import java.lang.reflect.Method;
public class ReflectTester
{
// 该方法实现对Customer对象的拷贝操作
public Object copy(Object object) throws Exception
{
Class<?> classType = object.getClass();
/* 生成新的对象的讨论
// 获得Constructor对象,此处获取第一个无参数的构造方法的
Constructor cons = classType.getConstructor(new Class[] {});//不带参数,所以传入一个为空的数组
// 通过构造方法来生成一个对象
Object obj = cons.newInstance(new Object[] {});
// 以上两行代码等价于:
Object obj11 = classType.newInstance(); // 这行代码无法处理构造函数有参数的情况
//用第二个带参数的构造方法生成对象
Constructor cons2 = classType.getConstructor(new Class[] {String.class, int.class});
Object obj2 = cons2.newInstance(new Object[] {"ZhangSan",20});
*/
Object objectCopy = classType.getConstructor(new Class[]{}).newInstance(new Object[]{});
//获得对象的所有成员变量
Field[] fields = classType.getDeclaredFields();
for(Field field : fields)
{
//获取成员变量的名字
String name = field.getName(); //获取成员变量的名字,此处为id,name,age
//System.out.println(name);
//获取get和set方法的名字
String firstLetter = name.substring(0,1).toUpperCase(); //将属性的首字母转换为大写
String getMethodName = "get" + firstLetter + name.substring(1);
String setMethodName = "set" + firstLetter + name.substring(1);
//System.out.println(getMethodName + "," + setMethodName);
//获取方法对象
Method getMethod = classType.getMethod(getMethodName, new Class[]{});
Method setMethod = classType.getMethod(setMethodName, new Class[]{field.getType()});//注意set方法需要传入参数类型
//调用get方法获取旧的对象的值
Object value = getMethod.invoke(object, new Object[]{});
//调用set方法将这个值复制到新的对象中去
setMethod.invoke(objectCopy, new Object[]{value});
}
return objectCopy;
}
public static void main(String[] args) throws Exception
{
Customer customer = new Customer("Tom",20);
customer.setId(1L);
ReflectTester tester = new ReflectTester();
Customer customer2 = (Customer)tester.copy(customer);
System.out.println(customer2.getId() + "," + customer2.getName() + "," + customer2.getAge());
}
}
class Customer
{
private long id;
private String name;
private int age;
public Customer(){}
public Customer(String name, int age)
{
this.name = name;
this.age = age;
}
public long getId()
{
return id;
}
public void setId(long id)
{
this.id = id;
}
public String getName()
{
return name;
}
public void setName(String name)
{
this.name = name;
}
public int getAge()
{
return age;
}
public void setAge(int age)
{
this.age = age;
}
}