java xml生成与解析_Java解析和生成XML
1、Jaxb处理java对象和xml之间转换常用的annotation有：
@XmlElement
@XmlRootElement
@XmlAttribute
@XmlAccessorType
@XmlAccessorOrder
@XmlTransient
@XmlJavaTypeAdapter
2、常用annotation使用说明
@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。
@XmlElement
@XmlElement将对象的属性映射为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;
@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 {}
@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;
@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。
@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
@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。
@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{//Do-nothing constructor for the derived classes.
protectedXmlAdapter() {}//Convert a value type to a bound type.
public abstractBoundType unmarshal(ValueType v);//Convert a bound type to a value type.
public abstractValueType marshal(BoundType v);
}
3、示例
Shop.java
importjava.io.FileReader;importjava.io.FileWriter;importjava.math.BigDecimal;importjava.util.Date;importjava.util.HashSet;importjava.util.Set;importjavax.xml.bind.JAXBContext;importjavax.xml.bind.Marshaller;importjavax.xml.bind.Unmarshaller;importjavax.xml.bind.annotation.XmlAccessType;importjavax.xml.bind.annotation.XmlAccessorOrder;importjavax.xml.bind.annotation.XmlAccessOrder;importjavax.xml.bind.annotation.XmlAccessorType;importjavax.xml.bind.annotation.XmlAttribute;importjavax.xml.bind.annotation.XmlElement;importjavax.xml.bind.annotation.XmlElementWrapper;importjavax.xml.bind.annotation.XmlRootElement;importjavax.xml.bind.annotation.XmlType;//设置生成的xml的根节点的名称
@XmlRootElement(name = "shop")//设置根据字段还是方法生成
@XmlAccessorType(XmlAccessType.FIELD)
@XmlAccessorOrder(XmlAccessOrder.ALPHABETICAL)
@XmlType(name= "shop", propOrder = { "name", "number", "describer", "address","orders"})public classShop {public static voidmain(String[] args) {
Set orders = new HashSet();
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.setOrders(orders);
FileWriter writer= null;try{
JAXBContext context= JAXBContext.newInstance(Shop.class);
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);
Unmarshaller unmarshal=context.createUnmarshaller();
FileReader reader= new FileReader("shop.xml") ;
Shop shop1=(Shop)unmarshal.unmarshal(reader);
Set orders1 =shop1.getOrders();for(Order order : orders1){
System.out.println("***************************");
System.out.println(order.getOrderNumber());
System.out.println(order.getCustomer().getName());
System.out.println("***************************");
}
}catch(Exception e) {
e.printStackTrace();
}
}
@XmlAttributeprivateString name;//@XmlElement
privateString number;
@XmlElementprivateString describer;
@XmlElementWrapper(name= "orders")
@XmlElement(name= "order")private Setorders;
@XmlElementprivateAddress address;publicShop() {
}publicShop(String name, String number, String describer, Address address) {this.name =name;this.number =number;this.describer =describer;this.address =address;
}publicString getName() {returnname;
}public voidsetName(String name) {this.name =name;
}publicString getNumber() {returnnumber;
}public voidsetNumber(String number) {this.number =number;
}publicString getDescriber() {returndescriber;
}public voidsetDescriber(String describer) {this.describer =describer;
}public SetgetOrders() {returnorders;
}public void setOrders(Setorders) {this.orders =orders;
}publicAddress getAddress() {returnaddress;
}public voidsetAddress(Address address) {this.address =address;
}
}
Order.java
importjava.math.BigDecimal;importjava.util.Date;importjavax.xml.bind.annotation.XmlAccessorType;importjavax.xml.bind.annotation.XmlAccessType;importjavax.xml.bind.annotation.XmlAttribute;importjavax.xml.bind.annotation.XmlRootElement;importjavax.xml.bind.annotation.XmlType;importjavax.xml.bind.annotation.adapters.XmlJavaTypeAdapter;
@XmlType(name="order",propOrder={"shopName","orderNumber","price","amount","purDate","customer"})
@XmlAccessorType(XmlAccessType.FIELD)
@XmlRootElementpublic classOrder {privateString shopName;
@XmlAttributeprivateString orderNumber;
@XmlJavaTypeAdapter(value=DateAdapter.class)privateDate purDate;privateBigDecimal price;private intamount;privateCustomer customer;publicOrder() {
}publicOrder(String shopName, String orderNumber, Date purDate,
BigDecimal price,intamount) {this.shopName =shopName;this.orderNumber =orderNumber;this.purDate =purDate;this.price =price;this.amount =amount;
}publicString getShopName() {returnshopName;
}public voidsetShopName(String shopName) {this.shopName =shopName;
}publicString getOrderNumber() {returnorderNumber;
}public voidsetOrderNumber(String orderNumber) {this.orderNumber =orderNumber;
}publicDate getPurDate() {returnpurDate;
}public voidsetPurDate(Date purDate) {this.purDate =purDate;
}publicBigDecimal getPrice() {returnprice;
}public voidsetPrice(BigDecimal price) {this.price =price;
}public intgetAmount() {returnamount;
}public void setAmount(intamount) {this.amount =amount;
}publicCustomer getCustomer() {returncustomer;
}public voidsetCustomer(Customer customer) {this.customer =customer;
}
}
Customer.java
importjava.util.Set;importjavax.xml.bind.annotation.XmlAccessorType;importjavax.xml.bind.annotation.XmlAccessType;importjavax.xml.bind.annotation.XmlAttribute;importjavax.xml.bind.annotation.XmlRootElement;importjavax.xml.bind.annotation.XmlType;
@XmlType
@XmlAccessorType(XmlAccessType.FIELD)
@XmlRootElementpublic classCustomer {
@XmlAttributeprivateString name;privateString gender;privateString phoneNo;privateAddress address;private Setorders;publicCustomer() {
}publicCustomer(String name, String gender, String phoneNo, Address address) {this.name =name;this.gender =gender;this.phoneNo =phoneNo;this.address =address;
}publicString getName() {returnname;
}public voidsetName(String name) {this.name =name;
}publicString getGender() {returngender;
}public voidsetGender(String gender) {this.gender =gender;
}publicString getPhoneNo() {returnphoneNo;
}public voidsetPhoneNo(String phoneNo) {this.phoneNo =phoneNo;
}publicAddress getAddress() {returnaddress;
}public voidsetAddress(Address address) {this.address =address;
}public SetgetOrders() {returnorders;
}public void setOrders(Setorders) {this.orders =orders;
}
}
Address.java
importjavax.xml.bind.annotation.XmlAccessorOrder;importjavax.xml.bind.annotation.XmlAccessOrder;importjavax.xml.bind.annotation.XmlAccessorType;importjavax.xml.bind.annotation.XmlAccessType;importjavax.xml.bind.annotation.XmlAttribute;importjavax.xml.bind.annotation.XmlElement;importjavax.xml.bind.annotation.XmlRootElement;importjavax.xml.bind.annotation.XmlType;
@XmlType(propOrder= { "state", "province", "city", "street", "zip"})
@XmlAccessorOrder(XmlAccessOrder.ALPHABETICAL)
@XmlAccessorType(XmlAccessType.NONE)
@XmlRootElementpublic classAddress {
@XmlAttributeprivateString state;
@XmlElementprivateString province;
@XmlElementprivateString city;
@XmlElementprivateString street;
@XmlElementprivateString zip;publicAddress() {super();
}publicAddress(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;
}publicString getState() {returnstate;
}public voidsetState(String state) {this.state =state;
}publicString getProvince() {returnprovince;
}public voidsetProvince(String province) {this.province =province;
}publicString getCity() {returncity;
}public voidsetCity(String city) {this.city =city;
}publicString getStreet() {returnstreet;
}public voidsetStreet(String street) {this.street =street;
}publicString getZip() {returnzip;
}public voidsetZip(String zip) {this.zip =zip;
}
}
输出：
100000
EveryThing
ZheJiang
HangZhou
XiHuRoad
310000
Mart
60
1
2016-11-23 14:51:40
male
13699990000
ShangHai
ShangHai
Huang
200000
Mart
80
1
2016-11-23 14:51:40
male
13699991000
JiangSu
NanJing
ZhongYangLu
210000
***************************LH59900
Jim***************************
***************************LH59800
David**************************
工具类JaxbUtil.java:
importjava.io.StringReader;importjava.io.StringWriter;importjava.util.Collection;importjava.util.concurrent.ConcurrentHashMap;importjava.util.concurrent.ConcurrentMap;importjavax.xml.bind.JAXBContext;importjavax.xml.bind.JAXBElement;importjavax.xml.bind.JAXBException;importjavax.xml.bind.Marshaller;importjavax.xml.bind.Unmarshaller;importjavax.xml.bind.annotation.XmlAnyElement;importjavax.xml.namespace.QName;importorg.apache.commons.lang3.Validate;importcom.thinkgem.jeesite.common.utils.Exceptions;importcom.thinkgem.jeesite.common.utils.Reflections;importcom.thinkgem.jeesite.common.utils.StringUtils;/*** 使用Jaxb2.0实现XMLJava Object的Mapper.
* 在创建时需要设定所有需要序列化的Root对象的Class.
* 特别支持Root对象是Collection的情形.*/
public classJaxbUtil {private static ConcurrentMap jaxbContexts = new ConcurrentHashMap();/*** Java Object->Xml without encoding.*/@SuppressWarnings("rawtypes")public staticString toXml(Object root) {
Class clazz=Reflections.getUserClass(root);return toXml(root, clazz, null);
}/*** Java Object->Xml with encoding.*/@SuppressWarnings("rawtypes")public staticString toXml(Object root, String encoding) {
Class clazz=Reflections.getUserClass(root);returntoXml(root, clazz, encoding);
}/*** Java Object->Xml with encoding.*/@SuppressWarnings("rawtypes")public staticString toXml(Object root, Class clazz, String encoding) {try{
StringWriter writer= newStringWriter();
createMarshaller(clazz, encoding).marshal(root, writer);returnwriter.toString();
}catch(JAXBException e) {throwExceptions.unchecked(e);
}
}/*** Java Collection->Xml without encoding, 特别支持Root Element是Collection的情形.*/@SuppressWarnings("rawtypes")public static String toXml(Collection>root, String rootName, Class clazz) {return toXml(root, rootName, clazz, null);
}/*** Java Collection->Xml with encoding, 特别支持Root Element是Collection的情形.*/@SuppressWarnings("rawtypes")public static String toXml(Collection>root, String rootName, Class clazz, String encoding) {try{
CollectionWrapper wrapper= newCollectionWrapper();
wrapper.collection=root;
JAXBElement wrapperElement = new JAXBElement(newQName(rootName),
CollectionWrapper.class, wrapper);
StringWriter writer= newStringWriter();
createMarshaller(clazz, encoding).marshal(wrapperElement, writer);returnwriter.toString();
}catch(JAXBException e) {throwExceptions.unchecked(e);
}
}/*** Xml->Java Object.*/@SuppressWarnings("unchecked")public static T fromXml(String xml, Classclazz) {try{
StringReader reader= newStringReader(xml);return(T) createUnmarshaller(clazz).unmarshal(reader);
}catch(JAXBException e) {throwExceptions.unchecked(e);
}
}/*** 创建Marshaller并设定encoding(可为null).
* 线程不安全，需要每次创建或pooling。*/@SuppressWarnings("rawtypes")public staticMarshaller createMarshaller(Class clazz, String encoding) {try{
JAXBContext jaxbContext=getJaxbContext(clazz);
Marshaller marshaller=jaxbContext.createMarshaller();
marshaller.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, Boolean.TRUE);if(StringUtils.isNotBlank(encoding)) {
marshaller.setProperty(Marshaller.JAXB_ENCODING, encoding);
}returnmarshaller;
}catch(JAXBException e) {throwExceptions.unchecked(e);
}
}/*** 创建UnMarshaller.
* 线程不安全，需要每次创建或pooling。*/@SuppressWarnings("rawtypes")public staticUnmarshaller createUnmarshaller(Class clazz) {try{
JAXBContext jaxbContext=getJaxbContext(clazz);returnjaxbContext.createUnmarshaller();
}catch(JAXBException e) {throwExceptions.unchecked(e);
}
}
@SuppressWarnings("rawtypes")protected staticJAXBContext getJaxbContext(Class clazz) {
Validate.notNull(clazz,"'clazz' must not be null");
JAXBContext jaxbContext=jaxbContexts.get(clazz);if (jaxbContext == null) {try{
jaxbContext= JAXBContext.newInstance(clazz, CollectionWrapper.class);
jaxbContexts.putIfAbsent(clazz, jaxbContext);
}catch(JAXBException ex) {throw new RuntimeException("Could not instantiate JAXBContext for class [" + clazz + "]: "
+ex.getMessage(), ex);
}
}returnjaxbContext;
}/*** 封装Root Element 是 Collection的情况.*/
public static classCollectionWrapper {
@XmlAnyElementprotected Collection>collection;
}
}
测试：
String s =JaxbUtil.toXml(shop);
System.out.println(s);
输出：
100000
EveryThing
ZheJiang
HangZhou
XiHuRoad
310000
Mart
80
1
2016-11-23 14:54:39
male
13699991000
JiangSu
NanJing
ZhongYangLu
210000
Mart
60
1
2016-11-23 14:54:39
male
13699990000
ShangHai
ShangHai
Huang
200000