Mode prototype maître en cinq minutes

public class UserEntity { private Long id; private String name; private Integer age; //....可能还有很多属性 //省略getter setter }

public class UserVO { private Long id; private String name; private Integer age; //....可能还有很多属性 //省略getter setter }

public class ObjectConvertUtil { public static UserVo convertUserEntityToUserVO(UserEntity userEntity) { if (userEntity == null) { return null; } UserVo userVo = new UserVo(); userVo.setId(userEntity.getId()); userVo.setName(userEntity.getName()); userVo.setAge(userEntity.getAge()); //如果还有更多属性呢？ return userVo; } }

BeanUtils.copy(); JSON.parseObject() Guava工具类 .....

//用户地址信息 public class UserAddress implements Serializable{ private String province; private String cityCode; public UserAddress(String province, String cityCode) { this.province = province; this.cityCode = cityCode; } } //用户信息 public class User implements Cloneable { private int age; private String name; //用户地址信息 private UserAddress userAddress; //getter setter 省略 @Override protected Object clone() throws CloneNotSupportedException { return super.clone(); } } //测试 public class UserTest { public static void main(String[] args) throws Exception { User user = new User(); user.setAge(20); user.setName("田维常"); UserAddress userAddress = new UserAddress("贵州", "梵净山"); user.setUserAddress(userAddress); User clone = (User) user.clone(); System.out.println("克隆前后UserAddress比较：" + (user.getUserAddress() == clone.getUserAddress())); } }

克隆前后 UserAddress 比较：true

//猴子，有身高体重和生日 public class Monkey { public int height; public int weight; public Date birthday; }

import java.io.Serializable; //孙悟空的金箍棒 public class JinGuBang implements Serializable{ public float h=100; public float d=10; //金箍棒变大 public void big(){ this.h *=10; this.d *=10; } //金箍棒变小 public void small(){ this.h /=10; this.d /=10; } }

import java.io.*; import java.util.Date; //孙悟空有七十二变,拔猴毛生成一个金箍棒 //使用JDK的克隆机制， //实现Cloneable并重写clone方法 public class QiTianDaSheng extends Monkey implements Cloneable, Serializable { public JinGuBang jinGuBang; public QiTianDaSheng() { this.birthday = new Date(); this.jinGuBang = new JinGuBang(); } @Override protected Object clone() throws CloneNotSupportedException { return this.deepClone(); } //深克隆 public QiTianDaSheng deepClone() { try { //内存中操作完成、对象读写，是通过字节码直接操作 //与序列化操作类似 ByteArrayOutputStream bos = new ByteArrayOutputStream(); ObjectOutputStream oos = new ObjectOutputStream(bos); oos.writeObject(this); ByteArrayInputStream bais = new ByteArrayInputStream(bos.toByteArray()); ObjectInputStream bis = new ObjectInputStream(bais); //完成一个新的对象,底层是使用new创建的一个对象 //详情可以了解readObject方法 QiTianDaSheng qiTianDaSheng = (QiTianDaSheng) bis.readObject(); //每个猴子的生日不一样，所以每次拷贝的时候，把生日改一下 qiTianDaSheng.birthday = new Date(); return qiTianDaSheng; } catch (Exception ex) { ex.printStackTrace(); return null; } } //浅克隆，就是简单的赋值 public QiTianDaSheng shalllowClone(QiTianDaSheng target) { QiTianDaSheng qiTianDaSheng = new QiTianDaSheng(); qiTianDaSheng.height = target.height; qiTianDaSheng.weight = target.weight; qiTianDaSheng.jinGuBang = target.jinGuBang; qiTianDaSheng.birthday = new Date(); return qiTianDaSheng; } }

public class DeepCloneTest { public static void main(String[] args) { QiTianDaSheng qiTianDaSheng = new QiTianDaSheng(); try { QiTianDaSheng newObject = (QiTianDaSheng) qiTianDaSheng.clone(); System.out.print("深克隆后 "); System.out.println("金箍棒是否一直：" + (qiTianDaSheng.jinGuBang == newObject.jinGuBang)); } catch (Exception ex) { ex.printStackTrace(); } QiTianDaSheng newObject=qiTianDaSheng.shalllowClone(qiTianDaSheng); System.out.print("浅克隆后 "); System.out.println("金箍棒是否一直：" + (qiTianDaSheng.jinGuBang == newObject.jinGuBang)); } }

深克隆后 金箍棒是否一直：false 浅克隆后 金箍棒是否一直：true