一.Jaxb处理java对象和xml之间转换常用的annotation有:
- @XmlType
- @XmlElement
- @XmlRootElement
- @XmlAttribute
- @XmlAccessorType
- @XmlAccessorOrder
- @XmlTransient
- @XmlJavaTypeAdapter
二.常用annotation使用说明
@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:
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:
@XmlAccessorType(XmlAccessType.FIELD)
@XmlRootElement
public class Address {}
4.@XmlAttribute
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。
相关推荐
JAXB注解相关技术JAXB注解相关技术JAXB注解相关技术JAXB注解相关技术JAXB注解相关技术JAXB注解相关技术
当使用的JDK为1.6版本的时候,JAXB注解命名空间使用到的jar包
Jaxb annotation 使用 Jaxb annotation初步使用
JAXB-XML注解-应用
JAXB注解 java 关于xml的注解,自动生成xml文件
JAXB能够使用Jackson对JAXB注解的支持实现(jackson-module-jaxb-annotations),既方便生成XML,也方便生成JSON,这样一来可以更好的标志可以转换为JSON对象的JAVA类。JAXB允许JAVA人员将JAVA类映射为XML表示方式
JAXB能够使用Jackson对JAXB注解的支持实现(jackson-module-jaxb-annotations),既方便生成XML,也方便生成JSON,这样一来可以更好的标志可以转换为JSON对象的JAVA类。JAXB允许JAVA人员将JAVA类映射为XML表示方式,...
JAXB能够使用Jackson对JAXB注解的支持实现(jackson-module-jaxb-annotations),既方便生成XML,也方便生成JSON,这样一来可以更好的标志可以转换为JSON对象的JAVA类。JAXB允许JAVA人员将JAVA类映射为XML表示方式,...
JAXB能够使用Jackson对JAXB注解的支持实现(jackson-module-jaxb-annotations),既方便生成XML,也方便生成JSON,这样一来可以更好的标志可以转换为JSON对象的JAVA类。JAXB允许JAVA人员将JAVA类映射为XML表示方式,...
使用jaxb生成XML例子,含有例子和注解解析
使用jaxb 实现xml——bean互转
教你使用jaxb解析xml,介绍了主要的注解,以及核心api
一个jaxb小项目的源码,可以帮助理解jaxb的执行和注解。
使用woodstax+jaxb进行xml的流解析,包括解析类,解析文件,所需jar包,带注解的实体类。提高了解析效率,减少了内存消耗。
Jaxb简单例子,学习注解及java与xml的互相转换,比较基础,大家互相学习
jaxbRss RSS对象的JAXB绑定 轻松地与任何jaxb支持的序列化格式之间进行编组/取消编组。 查看完整的文档: :
本人总结的jaxb详细开发步骤,结合注解
很好的jaxb入门示例 把所有注解标签都试一遍基本就OK了
jaxb XMl和BEAN互转实例(内含jar包),将jaxb封装成一个Util工具类,只需要通过对BEAN进行简单的注解就可以直接实现xml和bean之间的互转
JDK 自带JAXB 注解解析xml