当前位置:首页 > 开发 > 编程语言 > 编程 > 正文

Jaxb annotation初步使用

发表于: 2014-05-13   作者:sunjing   来源:转载   浏览次数:
摘要: 原文 http://www.cnblogs.com/fragranting/archive/2012/03/25/xml--jaxb.html 一.Jaxb处理java对象和xml之间转换常用的annotation @XmlType @XmlElement @XmlRootElement @XmlAttribute @XmlAccessorType @XmlAcces

原文 http://www.cnblogs.com/fragranting/archive/2012/03/25/xml--jaxb.html

一.Jaxb处理java对象和xml之间转换常用的annotation

  1. @XmlType
  2. @XmlElement
  3. @XmlRootElement
  4. @XmlAttribute
  5. @XmlAccessorType
  6. @XmlAccessorOrder
  7. @XmlTransient
  8. @XmlJavaTypeAdapter

二.常用annotation使用说明

  1. @XmlType
    @XmlType用在class类的注解,常与@XmlRootElement,@XmlAccessorType一起使用。它有三个属性:name、propOrder、namespace,经常使用的只有前两个属性。如:

@XmlType(name = "basicStruct", propOrder = {
    "intValue",
    "stringArray",
    "stringValue"
)
在使用@XmlType的propOrder 属性时,必须列出JavaBean对象中的所有属性,否则会报错。

 2.@XmlElement

  @XmlElement将java对象的属性映射为xml的节点,在使用@XmlElement时,可通过name属性改变java对象属性在xml中显示的名称。如:

 

  @XmlElement(name="Address")
  private String yourAddress;

 3.@XmlRootElement

  @XmlRootElement用于类级别的注解,对应xml的跟元素,常与 @XmlType 和 @XmlAccessorType一起使用。如:

 

  @XmlType
  @XmlAccessorType(XmlAccessType.FIELD)
  @XmlRootElement
  public class Address {}

 4.@XmlAttribute

  @XmlAttribute用于把java对象的属性映射为xml的属性,并可通过name属性为生成的xml属性指定别名。如:
  @XmlAttribute(name="Country")
  private String state;

 5.@XmlAccessorType

  @XmlAccessorType用于指定由java对象生成xml文件时对java对象属性的访问方式。常与@XmlRootElement、@XmlType一起使用。它的属性值是XmlAccessType的4个枚举值,分别为:

 

  XmlAccessType.FIELD:java对象中的所有成员变量

     XmlAccessType.PROPERTY:java对象中所有通过getter/setter方式访问的成员变量

  XmlAccessType.PUBLIC_MEMBER:java对象中所有的public访问权限的成员变量和通过getter/setter方式访问的成员变量

  XmlAccessType.NONE:java对象的所有属性都不映射为xml的元素

 

  注意:@XmlAccessorType的默认访问级别是XmlAccessType.PUBLIC_MEMBER,因此,如果java对象中的private成员变量设置了public权限的getter/setter方法,就不要在private变量上使用@XmlElement和@XmlAttribute注解,否则在由java对象生成xml时会报同一个属性在java类里存在两次的错误。同理,如果@XmlAccessorType的访问权限为XmlAccessType.NONE,如果在java的成员变量上使用了@XmlElement或@XmlAttribute注解,这些成员变量依然可以映射到xml文件。

 6.@XmlAccessorOrder

  @XmlAccessorOrder用于对java对象生成的xml元素进行排序。它有两个属性值:

  AccessorOrder.ALPHABETICAL:对生成的xml元素按字母书序排序

  XmlAccessOrder.UNDEFINED:不排序

 7.@XmlTransient

  @XmlTransient用于标示在由java对象映射xml时,忽略此属性。即,在生成的xml文件中不出现此元素。

 8.@XmlJavaTypeAdapter

  @XmlJavaTypeAdapter常用在转换比较复杂的对象时,如map类型或者格式化日期等。使用此注解时,需要自己写一个adapter类继承XmlAdapter抽象类,并实现里面的方法。

  @XmlJavaTypeAdapter(value=xxx.class),value为自己定义的adapter类

  XmlAdapter如下:

 

public abstract class XmlAdapter<ValueType,BoundType> {
    // Do-nothing constructor for the derived classes.
    protected XmlAdapter() {}
    // Convert a value type to a bound type.
    public abstract BoundType unmarshal(ValueType v);
    // Convert a bound type to a value type.
    public abstract ValueType marshal(BoundType v);
 }

 

三.示例

  1.Shop.java

 

package jaxb.shop;
import java.util.Set;
import javax.xml.bind.annotation.XmlAccessOrder;
import javax.xml.bind.annotation.XmlAccessType;
import javax.xml.bind.annotation.XmlAccessorType;
import javax.xml.bind.annotation.XmlAttribute;
import javax.xml.bind.annotation.XmlElement;
import javax.xml.bind.annotation.XmlRootElement;
import javax.xml.bind.annotation.XmlType;
import javax.xml.bind.annotation.XmlElementWrapper;
import javax.xml.bind.annotation.XmlAccessorOrder;
 
@XmlAccessorOrder (XmlAccessOrder.ALPHABETICAL)
@XmlAccessorType (XmlAccessType.FIELD)
@XmlType (name = "shop" , propOrder = { "name" , "number" , "describer" , "address" , "orders" })
@XmlRootElement (name = "CHMart" )
public class Shop {
     @XmlAttribute
     private String name;
     // @XmlElement
     private String number;
     @XmlElement
     private String describer;
     @XmlElementWrapper (name = "orders" )
     @XmlElement (name = "order" )
     private Set<Order> orders;
     @XmlElement
     private Address address;
     public Shop() {
     }
     public Shop(String name, String number, String describer, Address address) {
         this .name = name;
         this .number = number;
         this .describer = describer;
         this .address = address;
     }
      getter/setter略
//同时使用了@XmlType(propOrder={})和@XmlAccessorOrder(XmlAccessOrder.ALPHABETICAL),
但是生成的xml只按照propOrder定义的顺序生成元素

 

  2.Order.java

 

package jaxb.shop;
import java.math.BigDecimal;
import java.util.Date;
import javax.xml.bind.annotation.XmlAccessType;
import javax.xml.bind.annotation.XmlAccessorType;
import javax.xml.bind.annotation.XmlAttribute;
import javax.xml.bind.annotation.XmlRootElement;
import javax.xml.bind.annotation.XmlType;
import javax.xml.bind.annotation.adapters.XmlJavaTypeAdapter;
 
@XmlType (name= "order" ,propOrder={ "shopName" , "orderNumber" , "price" , "amount" , "purDate" ,
"customer" })
@XmlAccessorType (XmlAccessType.FIELD)
@XmlRootElement
public class Order {
//  @XmlElement  
     private String shopName;
     @XmlAttribute
     private String orderNumber;
//  @XmlElement
     @XmlJavaTypeAdapter (value=DateAdapter. class )
     private Date purDate;
//  @XmlElement
     private BigDecimal price;
//  @XmlElement
     private int amount;
//  @XmlElement
     private Customer customer;
     public Order() {
     }
     public Order(String shopName, String orderNumber, Date purDate,
             BigDecimal price, int amount) {
         this .shopName = shopName;
         this .orderNumber = orderNumber;
         this .purDate = purDate;
         this .price = price;
         this .amount = amount;
     }
getter/setter略
//@XmlAccessorType(XmlAccessType.FIELD),所以此处注释掉了@XmlElement,xml中依然会生成这些元素

 

  3.Customer.java

 

package jaxb.shop;
 
import java.util.Set;
import javax.xml.bind.annotation.XmlType;
import javax.xml.bind.annotation.XmlAttribute;
import javax.xml.bind.annotation.XmlElement;
import javax.xml.bind.annotation.XmlRootElement;
import javax.xml.bind.annotation.XmlAccessType;
import javax.xml.bind.annotation.XmlAccessorType;
 
@XmlType
@XmlAccessorType (XmlAccessType.FIELD)
@XmlRootElement
public class Customer {
     @XmlAttribute
     private String name;
     private String gender;
     private String phoneNo;
     private Address address;
     private Set<Order> orders;
     public Customer() {
     }
     public Customer(String name, String gender, String phoneNo, Address address) {
         this .name = name;
         this .gender = gender;
         this .phoneNo = phoneNo;
         this .address = address;
     }
getter/setter略

 

  4.Address.java

 

package jaxb.shop;
 
import javax.xml.bind.annotation.XmlAttribute;
import javax.xml.bind.annotation.XmlType;
import javax.xml.bind.annotation.XmlElement;
import javax.xml.bind.annotation.XmlRootElement;
import javax.xml.bind.annotation.XmlAccessType;
import javax.xml.bind.annotation.XmlAccessorType;
import javax.xml.bind.annotation.XmlAccessOrder;
import javax.xml.bind.annotation.XmlAccessorOrder;
 
@XmlType (propOrder={ "state" , "province" , "city" , "street" , "zip" })
@XmlAccessorOrder (XmlAccessOrder.ALPHABETICAL)
@XmlAccessorType (XmlAccessType.NONE)
@XmlRootElement
public class Address {
     @XmlAttribute  
     private String state;     
     @XmlElement
     private String province;     
     @XmlElement
     private String city;
     @XmlElement
     private String street;     
     @XmlElement
     private String zip;
 
     public Address() {
         super ();
     }
     public Address(String state, String province, String city, String street,
             String zip) {
         super ();
         this .state = state;
         this .province = province;
         this .city = city;
         this .street = street;
         this .zip = zip;
     }
getter/setter略
//注意:虽然@XmlAccessorType为XmlAccessType.NONE,但是在java类的私有属性上加了@XmlAttribute和
@XmlElement注解后,这些私有成员会映射生成xml的元素

 

  5.DateAdapter.java

 

package jaxb.shop;
 
import java.util.Date;
import java.text.SimpleDateFormat;
import javax.xml.bind.annotation.adapters.XmlAdapter;
public class DateAdapter extends XmlAdapter<String, Date> {
     private String pattern = "yyyy-MM-dd HH:mm:ss" ;
     SimpleDateFormat fmt = new SimpleDateFormat(pattern);     
     @Override
     public Date unmarshal(String dateStr) throws Exception {         
         return fmt.parse(dateStr);
     }
 
     @Override
     public String marshal(Date date) throws Exception {         
         return fmt.format(date);
     }
 
}
//用于格式化日期在xml中的显示格式,并且由xml unmarshal为java对象时,将字符串解析为Date对象

 

  6.ShopTest.java

 

package jaxb.shop;
 
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.math.BigDecimal;
import java.util.Date;
import java.util.HashSet;
import java.util.Set;
 
import javax.xml.bind.JAXBContext;
import javax.xml.bind.JAXBException;
import javax.xml.bind.Marshaller;
import javax.xml.bind.Unmarshaller;
 
public class ShopTest {
     public static void main(String[] args) throws JAXBException, IOException{
         Set<Order> orders = new HashSet<Order>();         
         Address address1 = new Address( "China" , "ShangHai" , "ShangHai" , "Huang" , "200000" );
         Customer customer1 = new Customer( "Jim" , "male" , "13699990000" , address1);
         Order order1 = new Order( "Mart" , "LH59900" , new Date(), new BigDecimal( 60 ), 1 );
         order1.setCustomer(customer1);
         
         Address address2 = new Address( "China" , "JiangSu" , "NanJing" , "ZhongYangLu" , "210000" );
         Customer customer2 = new Customer( "David" , "male" , "13699991000" , address2);
         Order order2 = new Order( "Mart" , "LH59800" , new Date(), new BigDecimal( 80 ), 1 );
         order2.setCustomer(customer2);         
         orders.add(order1);
         orders.add(order2);
         
         Address address3 = new Address( "China" , "ZheJiang" , "HangZhou" , "XiHuRoad" , "310000" );
         Shop shop = new Shop( "CHMart" , "100000" , "EveryThing" ,address3);
         shop.setOrder(orders);
         
         FileWriter writer = null ;
         JAXBContext context = JAXBContext.newInstance(Shop. class );
         try {
             Marshaller marshal = context.createMarshaller();
             marshal.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, true );
             marshal.marshal(shop, System.out);
             
             writer = new FileWriter( "shop.xml" );
             marshal.marshal(shop, writer);
         } catch (Exception e) {
             e.printStackTrace();
         }
         
         Unmarshaller unmarshal = context.createUnmarshaller();
         FileReader reader = new FileReader( "shop.xml" ) ;
         Shop shop1 = (Shop)unmarshal.unmarshal(reader);
        
         Set<Order> orders1 = shop1.getOrder();
         for (Order order : orders1){
             System.out.println( "***************************" );
             System.out.println(order.getOrderNumber());
             System.out.println(order.getCustomer().getName());
             System.out.println( "***************************" );
         }
     }
}

 

  7.生成的xml文件

 

<?xml version= "1.0" encoding= "UTF-8" standalone= "yes" ?>
<CHMart name= "CHMart" >
     <number> 100000 </number>
     <describer>EveryThing</describer>
     <address state= "China" >
         <province>ZheJiang</province>
         <city>HangZhou</city>
         <street>XiHuRoad</street>
         <zip> 310000 </zip>
     </address>
     <orders>
         <order orderNumber= "LH59800" >
             <shopName>Mart</shopName>
             <price> 80 </price>
             <amount> 1 </amount>
             <purDate> 2012 - 03 - 25 12 : 57 : 23 </purDate>
             <customer name= "David" >
                 <gender>male</gender>
                 <phoneNo> 13699991000 </phoneNo>
                 <address state= "China" >
                     <province>JiangSu</province>
                     <city>NanJing</city>
                     <street>ZhongYangLu</street>
                     <zip> 210000 </zip>
                 </address>
             </customer>
         </order>
         <order orderNumber= "LH59900" >
             <shopName>Mart</shopName>
             <price> 60 </price>
             <amount> 1 </amount>
             <purDate> 2012 - 03 - 25 12 : 57 : 23 </purDate>
             <customer name= "Jim" >
                 <gender>male</gender>
                 <phoneNo> 13699990000 </phoneNo>
                 <address state= "China" >
                     <province>ShangHai</province>
                     <city>ShangHai</city>
                     <street>Huang</street>
                     <zip> 200000 </zip>
                 </address>
             </customer>
         </order>
     </orders>
</CHMart>

 

  以上是以一个简单的商店订单模型作为示例。

Jaxb annotation初步使用

  • 0

    开心

    开心

  • 0

    板砖

    板砖

  • 0

    感动

    感动

  • 0

    有用

    有用

  • 0

    疑问

    疑问

  • 0

    难过

    难过

  • 0

    无聊

    无聊

  • 0

    震惊

    震惊

编辑推荐
@XmlRootElement @XmlRootElement 注解用于标注类或枚举类型,用它标注的类在映射后的 schema 中会
2 jaxb
< xmlnamespace prefix ="o" ns ="urn:schemas-microsoft-com:office:office" /> 一、前言。
前几天,Hibernate出了3.5的Final版了,没事就来尝鲜下了,这里主要是使用下Annoation,因为新版的H
WebService传递XML文档,当然也可以传递JSON对象。这节我只针对传递XML,那么JAVA绑定成XML,服务端
WebService传递XML文档,当然也可以传递JSON对象。这节我只针对传递XML,那么JAVA绑定成XML,服务端
摘 要 Java Architecture for XML Binding (JAXB) 是一项可以根据XML 模式产生Java类的Java技术。该
摘 要 Java Architecture for XML Binding (JAXB) 是一项可以根据XML 模式产生Java类的Java技术。该
简介 在SQL Server中,索引是一种增强式的存在,这意味着,即使没有索引,SQL Server仍然可以实现应
ASP.NET的三种控件DataGrid,DataList和Repeater .前两种控件使用的比较多,Repeater 用得比较少。但
Spinner中的选项数据通过ArrayAdapter设置,其中的数据来源可以来自程序中数组,也可以来自xml中自
版权所有 IT知识库 CopyRight © 2009-2015 IT知识库 IT610.com , All Rights Reserved. 京ICP备09083238号