java 中设计模式（值对象）的实例详解

import java.io.Serializable;//值对象的命名规范: XxxValueObject, XxxVO, XxxModel//1实现序列化接口public class AddressVO implements Serializable {  private static final long serialVersionUID = 1L;  // 2私有化所有成员变量  private String userId;  private String name;  private int age;  private boolean man; //变量名建议不要取成isMan(JSP碰到这种情况会有bug)  private String address;  // 3 必须要有一个默认的空参构造  public AddressVO() {  }  // 4 写所有成员变量的setter-getter方法---boolean型变量的getter方法写成isXXX()的形式  public String getUserId() {    return userId;  }  public void setUserId(String userId) {    this.userId = userId;  }  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;  }  public boolean isMan() {    return man;  }  public void setMan(boolean man) {    this.man = man;  }  public String getAddress() {    return address;  }  public void setAddress(String address) {    this.address = address;  }  //5 建议写equals,hashCode,toString这几个方法  @Override  public int hashCode() {    final int prime = 31;    int result = 1;    result = prime * result + ((userId == null) ? 0 : userId.hashCode());    return result;  }  @Override  public boolean equals(Object obj) {    if (this == obj)      return true;    if (obj == null)      return false;    if (getClass() != obj.getClass())      return false;    AddressVO other = (AddressVO) obj;    if (userId == null) {      if (other.userId != null)        return false;    } else if (!userId.equals(other.userId))      return false;    return true;  }  @Override  public String toString() {    return "AddressVO [userId=" + userId + ", name=" + name + ", age="        + age + ", man=" + man + ", address=" + address + "]";  }}