進(jìn)入實(shí)踐之前，最好找篇文章先了解一下 xmlbeans 是用來做什么的
參考資料：
http://xmlbeans.apache.org/參考文章：
XML-Java Data Binding Using XMLBeansxmlbeans bea 貢獻(xiàn)的一個(gè)開源項(xiàng)目，目的是使xml 文件直接轉(zhuǎn)化為java 對(duì)象，對(duì)java 對(duì)象的操作可直接存為xml 文件，省去了文檔驗(yàn)證過程。
實(shí)現(xiàn)原理：先定義 xml schema descripter ,編譯定義的 *.xsd 文件，引入編譯后生成的.jar 包。與 xmlbeans-Home\lib\xbean.jar 就可以在開發(fā)項(xiàng)目中使用了。
- Install XMLBeans.
- Compile your schema. Use scomp to compile the schema, generating and jarring Java types. For example, to create a employeeschema.jar from an employeesschema.xsd file:
scomp -out employeeschema.jar employeeschema.xsd
- Write code. With the generated JAR on your classpath, write code to bind an XML instance to the Java types representing your schema. Here's an example that would use types generated from an employees schema:
File xmlFile = new File("c:\employees.xml");
// Bind the instance to the generated XMLBeans types.
EmployeesDocument empDoc =
EmployeesDocument.Factory.parse(xmlFile);
// Get and print pieces of the XML instance.
Employees emps = empDoc.getEmployees();
Employee[] empArray = emps.getEmployeeArray();
for (int i = 0; i < empArray.length; i++)
{
System.out.println(empArray[i]);
}
實(shí)踐中遇到的問題：
如何修改編譯shema 產(chǎn)生的java 類的package 目錄結(jié)構(gòu)？
參考：http://wiki.apache.org/xmlbeans/XmlBeansFaq#configPackageName
Can I change the default package names for the java classes generated from my schema?
You can create a file that ends in .xsdconfig to map targetnamespace to packagename. Put the .xsdconfig file in the same directory as the .xsd that you are compiling. Here is an example .xsdconfig:
<!-- An xsdconfig file must begin with a "config" element in the
http://www.bea.com/2002/09/xbean/config namespace. Also, be sure
to declare any namespaces used to qualify types in your schema (here,
the namespace corresponding to the pol prefix. -->
<xb:config xmlns:pol="http://openuri.org/easypoLocal"
xmlns:xb="http://www.bea.com/2002/09/xbean/config">
<!-- Use the "namespace" element to map a namespace to the Java package
name that should be generated. -->
<xb:namespace uri="http://openuri.org/easypoLocal">
<xb:package>org.openuri.easypo.xsdconfig</xb:package>
</xb:namespace>
<!-- Use the "qname" element to map schema type names to generated
Java type names. In these examples, the name attribute's value is the
XML element name; the javaname attribute's value is the Java type
that should be generated. -->
<xb:qname name="pol:CUST" javaname="Customer"/>
<xb:qname name="pol:PURCH_ORDER" javaname="PurchaseOrder"/>
</xb:config>
Notice that you can also map specific element/attribute names to java names.
Note: If schema doesn't include targenamespace then use
<xb:namespace uri="##any">
<xb:package>org.openuri.easypo.xsdconfig</xb:package>
</xb:namespace>
to specify package names
Note: XmlBeans doesn’t support using two or more sets of java classes (in different packages) mapped to schema types/elements that have the same names and target namespaces, using all in the same class loader. Depending on the direction you are using for the java classes to schema types mapping, some features might not work correctly. This is because even though the package names for the java classes are different, the schema location for the schema metadata (.xsb files) is the same and contains the corresponding implementing java class, so the JVM will always pick up the first on the classpath. This can be avoided if multiple class loaders are used.
先看一下 scomp 命令: xmlbeans-home/bin 要加入到path 中，
scomp 參數(shù)圖
編寫自己的schema文件：weather_latlong.xsd
<xsd:schema
xmlns:xsd="http://www.w3.org/2001/XMLSchema"
xmlns:ct="http://beans.jhalo.com"
targetNamespace="http://beans.jhalo.com"
elementFormDefault="qualified">
<!-- This XML Schema describes xml documents
containing either weather details or latlong
details of a location based on Zipcode Two Global
elements Weather and Latlong, and one Global
Attribute Zipcode are declared.-->
<xsd:element name="Weather">
<xsd:complexType>
<xsd:sequence>
<xsd:element name="Temperature"
type="xsd:float"/>
<xsd:element name="Humidity"
type="xsd:float"/>
<xsd:element name="Visibility"
type="xsd:float"/>
<xsd:element name="Datetime"
type="xsd:dateTime"/>
</xsd:sequence>
<xsd:attribute ref="ct:Zipcode"/>
</xsd:complexType>
</xsd:element>
<xsd:element name="Latlong">
<xsd:complexType>
<xsd:sequence>
<xsd:element name="Latitude"
type="xsd:string"/>
<xsd:element name="Longitude"
type="xsd:string"/>
</xsd:sequence>
<xsd:attribute ref="ct:Zipcode"/>
</xsd:complexType>
</xsd:element>
<xsd:attribute name="Zipcode"
type="xsd:string"/>
</xsd:schema>
#
2
編寫myconfig.xsdconfig 存放同一目錄
#
<xb:config xmlns:xb="http://xml.apache.org/xmlbeans/2004/02/xbean/config"
xmlns:ct="http://beans.jhalo.com">
<xb:namespace uri="http://beans.jhalo.com http://services.jhalo.com">
<xb:package>org.jhalo</xb:package>
</xb:namespace>
<xb:namespace uri="##any">
<xb:prefix>Xml</xb:prefix>
<xb:suffix>Bean</xb:suffix>
</xb:namespace>
<xb:qname name="ct:Zipcode" javaname="Zip" />
<xb:qname name="ct:Datetime" javaname="Today" />
</xb:config>
如果不使用myconfig.xsdconfig 進(jìn)行編譯
scomp -out weather.jar weather_latlong.xsd
生成的 weather.jar 為：com/jhalo/beans/xxxx
使用 .xsdconfig 編譯
scomp -out weather.jar weather_latlong.xsd myconfig.xsdconfig
生成jar 結(jié)構(gòu)為： org/jhalo/
在寫測(cè)試程序發(fā)現(xiàn), Datetime -->Today 也改變了。
import org.apache.xmlbeans.*;
import org.jhalo.XmlLatlongDocumentBean;
import org.jhalo.XmlWeatherDocumentBean;
XmlWeatherDocumentBean wdoc;
XmlWeatherDocumentBean.Weather w;
wdoc = XmlWeatherDocumentBean.Factory.newInstance();
w = wdoc.addNewWeather();
w.setToday(Calendar.getInstance());
完畢.:)~
方向:分布式系統(tǒng)設(shè)計(jì)