jaxb解析xml 实例2

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通过jaxb方式把xml文件映射成bean对象。

1、新建java工程或者web工程都可以。
2、通过精简必须导入jar包
         activation.jar
        jaxb-api-2.0.jar
        jaxb-impl-2.0.1.jar
        jsr173_api-1.0.jar
3、 新建xml文件
    <?xml version="1.0" encoding="UTF-8"?>
    <root>

<template
   start="true"
   ip="127.0.0.1"
   port="3344"
   server="server"
/>
<template ... ... />
    </root>

4、新建bean对象，xml的映射文件。
Vo.java 如下
  
Java代码  收藏代码

    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;  
      
    @XmlAccessorType(XmlAccessType.FIELD)  
    @XmlType(name = "", propOrder = {  
    })  
    @XmlRootElement(name = "[color=red]template[/color]")  
    public class Vo {  
      
        @XmlAttribute  
        private String start;  
        @XmlAttribute  
        private String ip;  
        @XmlAttribute  
        private String port;  
        @XmlAttribute  
        private String server;  
          
          
        public String getStart() {  
            return start;  
        }  
        public void setStart(String start) {  
            this.start = start;  
        }  
        public String getIp() {  
            return ip;  
        }  
        public void setIp(String ip) {  
            this.ip = ip;  
        }  
        public String getPort() {  
            return port;  
        }  
        public void setPort(String port) {  
            this.port = port;  
        }  
        public String getServer() {  
            return server;  
        }  
        public void setServer(String server) {  
            this.server = server;  
        }  
    }  
         


该文件对应xml文件中 循环节点 template 元素

Root.java 文件如下
Java代码  收藏代码

    import java.util.ArrayList;  
    import java.util.List;  
      
    import javax.xml.bind.annotation.XmlAccessType;  
    import javax.xml.bind.annotation.XmlAccessorType;  
    import javax.xml.bind.annotation.XmlRootElement;  
    import javax.xml.bind.annotation.XmlType;  
      
    @XmlAccessorType(XmlAccessType.FIELD)  
    @XmlType(name = "", propOrder = {  
    })  
    @XmlRootElement(name = "[color=blue]root[/color]")  
    public class Root {  
          
        protected List<Vo> [color=red]template[/color];  
          
        public List<Vo> getTemplateList() {  
            if (template == null) {  
                template = new ArrayList<Vo>();  
            }  
            return this.template;  
        }  
    }  



注意bean对象与xml映射的关系。

5、 解析xml为bean类
Java代码  收藏代码

    public static void gernateConfig() throws Exception{  
            StringBuffer buffer  = null;  
            JAXBContext jaxbContext;  
            try {  
                               //读入xml文件流  
                               InputStream is = Excecute.class.getResourceAsStream(“/conf/config.xml”);  
                BufferedReader in = new BufferedReader(new InputStreamReader(is));  
                buffer = new StringBuffer();  
                String line = "";  
                while ((line = in.readLine()) != null) {  
                    buffer.append(line);  
                }  
                  
                //加载映射bean类  
                jaxbContext = JAXBContext.newInstance(Root.class);  
                               //创建解析  
                Unmarshaller um = jaxbContext.createUnmarshaller();  
                StreamSource streamSource = new StreamSource(new StringReader(buffer.toString()));  
                Root root = (Root) um.unmarshal(streamSource);   
            } catch (Exception e) {  
                e.printStackTrace();  
                throw new Exception(e.getMessage());  
            }  
        }  



6、 把bean对象生成xml字符串方法
Java代码  收藏代码

    public static String gernateConfigXml(Root root) throws Exception {  
            if (root != null) {  
                try {  
                    JAXBContext context = JAXBContext.newInstance(Root.class);  
                    Marshaller m = context.createMarshaller();  
                    m.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, true);  
                    Writer writer = new StringWriter();  
                    m.marshal(root, writer);  
                    try {  
                        String xml = writer.toString();  
                        writer.flush();  
                        writer.close();  
                        return xml;  
                    } catch (IOException e) {  
                        return "";  
                    }  
                } catch (Exception e) {  
                    throw new Exception("失败!");  
                }  
            } else {  
                return null;  
            }  
        }  

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