Java下3中XML解析 DOM方式、SAX方式和StAX方式

先简单说下前三种方式：

DOM方式：个人理解类似.net的XmlDocument，解析的时候效率不高，占用内存，不适合大XML的解析；
SAX方式：基于事件的解析，当解析到xml的某个部分的时候，会触发特定事件，可以在自定义的解析类中定义当事件触发时要做得事情；个人感觉一种很另类的方式，不知道.Net体系下是否有没有类似的方式？
StAX方式：个人理解类似.net的XmlReader方式，效率高，占用内存少，适用大XML的解析；
不过SAX方式之前也用过，本文主要介绍JAXB，这里只贴下主要代码：

代码如下:

import java.util.ArrayList;

import java.util.List;
import org.xml.sax.Attributes;
import org.xml.sax.SAXException;
import org.xml.sax.helpers.DefaultHandler;
public class ConfigParser extends DefaultHandler {
    private String currentConfigSection;
     public SysConfigItem sysConfig;
     public List<InterfaceConfigItem> interfaceConfigList;
     public List<FtpConfigItem> ftpConfigList;
     public List<AdapterConfigItem> adapterConfigList;
     public void startDocument() throws SAXException {
         sysConfig = new SysConfigItem();
         interfaceConfigList = new ArrayList<InterfaceConfigItem>();
         ftpConfigList = new ArrayList<FtpConfigItem>();
         adapterConfigList = new ArrayList<AdapterConfigItem>();
     }
     public void endDocument() throws SAXException {
     }
     public void startElement(String uri, String localName, String qName, Attributes attributes) throws SAXException {
         if (qName.equalsIgnoreCase("Item") && attributes.getLength() > 0) {
             if (currentConfigSection.equalsIgnoreCase("SysConfigItem")) {
                 sysConfig = new SysConfigItem(attributes);
             } else if (currentConfigSection.equalsIgnoreCase("InterfaceConfigItems")) {
                 interfaceConfigList.add(new InterfaceConfigItem(attributes));
             } else if (currentConfigSection.equalsIgnoreCase("FtpConfigItems")) {
                 ftpConfigList.add(new FtpConfigItem(attributes));
             } else if (currentConfigSection.equalsIgnoreCase("AdapterConfigItems")) {
                 adapterConfigList.add(new AdapterConfigItem(attributes));
             }
         } else {
             currentConfigSection = qName;
         }
     }
     public void endElement(String uri, String localName, String qName) throws SAXException {
     }
     public void characters(char ch[], int start, int length) throws SAXException {
     }
 }

代码如下:

import java.lang.reflect.Field;
import java.text.DateFormat;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;
import org.xml.sax.Attributes;
public class ConfigItemBase {
  private static DateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
  public ConfigItemBase() {
  }
  /**
   * 目前只支持几种常用类型 如果需要支持其他类型，请修改这里的代码
   *
   * @param attributes
   */
  public ConfigItemBase(Attributes attributes) {
      Class<?> cls = this.getClass();
      Field[] fields = cls.getDeclaredFields();
      for (Field field : fields) {
          String fieldType = field.getType().getSimpleName();
          for (int i = 0; i < attributes.getLength(); i++) {
              if (attributes.getQName(i).equalsIgnoreCase(field.getName())) {
                  field.setAccessible(true);
                  try {
                      if (fieldType.equalsIgnoreCase("String")) {
                          field.set(this, attributes.getValue(attributes.getQName(i)));
                      } else if (fieldType.equalsIgnoreCase("Integer")) {
                          field.set(this, Integer.valueOf(attributes.getValue(attributes.getQName(i))));
                      } else if (fieldType.equalsIgnoreCase("Double")) {
                          field.set(this, Double.valueOf(attributes.getValue(attributes.getQName(i))));
                      } else if (fieldType.equalsIgnoreCase("Date")) {
                          field.set(this, GetDate(attributes.getValue(attributes.getQName(i))));
                      } else {
                          System.out.println("Warning:Unhandler Field(" + field.getName() + "-" + fieldType + ")");
                      }
                  } catch (IllegalArgumentException e) {
                      e.printStackTrace();
                  } catch (IllegalAccessException e) {
                      e.printStackTrace();
                  }
                  break;
              }
          }
      }
  }
  public String toString() {
      String result = "";
      Class<?> cls = this.getClass();
      String classNameString = cls.getName();
      result += classNameString.substring(classNameString.lastIndexOf('.') + 1, classNameString.length()) + ":";
      Field[] fields = cls.getDeclaredFields();
      for (Field field : fields) {
          try {
              result += field.getName() + "=" + field.get(this) + ";";
          } catch (IllegalArgumentException e) {
              e.printStackTrace();
          } catch (IllegalAccessException e) {
              e.printStackTrace();
          }
      }
      return result;
  }
  /**
   * 处理时间类型属性（时间格式要求为：yyyy-MM-dd hh:mm:ss）
   *
   * @param dateString
   * @return
   */
  private static Date GetDate(String dateString) {
      Date date = null;
      try {
          date = dateFormat.parse(dateString);
      } catch (ParseException e) {
          e.printStackTrace();
      }
      return date;
  }
}

下面重点介绍一下最方便的:JAXB(Java Architecture for XML Binding)

这里用比较复杂的移动BatchSyncOrderRelationReq接口XML做为示例（感觉能解这个大家基本上够用了），报文格式如下（SvcCont里的CDATA内容是报文体，太恶心了）：


代码如下:

<?xml version="1.0" encoding="UTF-8" standalone="yes" ?>
<InterBOSS>
  <Version>0100</Version>
  <TestFlag>0</TestFlag>
  <BIPType>
      <BIPCode>BIP2B518</BIPCode>
      <ActivityCode>T2101518</ActivityCode>
      <ActionCode>0</ActionCode>
  </BIPType>
  <RoutingInfo>
      <OrigDomain>BOSS</OrigDomain>
      <RouteType>routeType</RouteType>
      <Routing>
          <HomeDomain>XXXX</HomeDomain>
          <RouteValue>routeValue</RouteValue>
      </Routing>
  </RoutingInfo>
  <TransInfo>
      <SessionID>2013041017222313925676</SessionID>
      <TransIDO>2013041017222313925676</TransIDO>
      <TransIDOTime>20130410172223</TransIDOTime>
      <TransIDH></TransIDH>
      <TransIDHTime></TransIDHTime>
  </TransInfo>
  <SNReserve>
      <TransIDC></TransIDC>
      <ConvID></ConvID>
      <CutOffDay></CutOffDay>
      <OSNTime></OSNTime>
      <OSNDUNS></OSNDUNS>
      <HSNDUNS></HSNDUNS>
      <MsgSender></MsgSender>
      <MsgReceiver></MsgReceiver>
      <Priority></Priority>
      <ServiceLevel></ServiceLevel>
      <SvcContType></SvcContType>
  </SNReserve>
  <Response>
      <RspType>rspType</RspType>
      <RspCode>rspCode</RspCode>
      <RspDesc>rspDesc</RspDesc>
  </Response>
  <SvcCont><![CDATA[<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<batchSyncOrderRelationReq>
  <msgTransactionID>210001BIP2B518130410172223651627</msgTransactionID>
  <reqNum>2</reqNum>
  <reqBody>
      <oprNumb>210001BIP2B518130410172224341871</oprNumb>
      <subscriptionInfo>
          <oprTime>oprTime1</oprTime>
          <actionID>actionId1</actionID>
          <brand>brand1</brand>
          <effTime>effTime1</effTime>
          <expireTime>expireTime1</expireTime>
          <feeUser_ID>feeUserId1</feeUser_ID>
          <destUser_ID>destUserId1</destUser_ID>
          <actionReasonID>actionId1</actionReasonID>
          <servType>servType1</servType>
          <subServType>subServType1</subServType>
          <SPID>spId1</SPID>
          <SPServID>spServId1</SPServID>
          <accessMode>accessMode1</accessMode>
          <servParamInfo>
              <para_num>0</para_num>
              <para_info>
                  <para_name></para_name>
                  <para_value></para_value>
              </para_info>
          </servParamInfo>
          <feeType>feeType1</feeType>
      </subscriptionInfo>
  </reqBody>
  <reqBody>
      <oprNumb>210001BIP2B518130410172224420909</oprNumb>
      <subscriptionInfo>
          <oprTime>oprTime2</oprTime>
          <actionID>actionId2</actionID>
          <brand>brand2</brand>
          <effTime>effTime2</effTime>
          <expireTime>expireTime2</expireTime>
          <feeUser_ID>feeUserId2</feeUser_ID>
          <destUser_ID>destUserId2</destUser_ID>
          <actionReasonID>actionId2</actionReasonID>
          <servType>servType2</servType>
          <subServType>subServType2</subServType>
          <SPID>spId2</SPID>
          <SPServID>spServId2</SPServID>
          <accessMode>accessMode2</accessMode>
          <servParamInfo>
              <para_num>0</para_num>
              <para_info>
                  <para_name></para_name>
                  <para_value></para_value>
              </para_info>
          </servParamInfo>
          <feeType>feeType2</feeType>
      </subscriptionInfo>
  </reqBody>
</batchSyncOrderRelationReq>]]></SvcCont>
</InterBOSS>

解码代码如下：


代码如下:

@XmlRootElement(name = "batchSyncOrderRelationReq")

@XmlAccessorType(XmlAccessType.FIELD)
 public class BatchSyncOrderRelationReq extends BossMessage<BatchSyncOrderRelationReq> {
     @XmlElement(name = "msgTransactionID")
     private String msgTransactionId = "";
     @XmlElement(name = "reqNum")
     private String reqNum = "";
    @XmlElement(name = "reqBody")
    private List<BatchSyncOrderRelationReqBody> reqBodyList;
    public BatchSyncOrderRelationReq() {
    }
    public String getMsgTransactionId() {
        return this.msgTransactionId;
    }
    public void setMsgTransactionId(String msgTransactionId) {
        this.msgTransactionId = msgTransactionId;
    }
    public String getReqNum() {
        return this.reqNum;
    }
    public void setReqNum(String reqNum) {
        this.reqNum = reqNum;
    }
    public List<BatchSyncOrderRelationReqBody> getReqBodyList() {
        return this.reqBodyList;
    }
    public void setReqBodyList(List<BatchSyncOrderRelationReqBody> reqBodyList) {
        this.reqBodyList = reqBodyList;
    }
     @Override
     public BatchSyncOrderRelationReq Deserialized(String interBossXmlContent) throws BusinessException {
         try {
             // deserialized for head
             JAXBContext jaxbCxt4Head = JAXBContext.newInstance(MessageHead.class);
             Unmarshaller unmarshaller4Head = jaxbCxt4Head.createUnmarshaller();
             MessageHead head = (MessageHead) unmarshaller4Head.unmarshal(new StringReader(interBossXmlContent));
             // deserialized for SyncOrderRelationReq body
             JAXBContext jaxbCxt4Body = JAXBContext.newInstance(BatchSyncOrderRelationReq.class);
             Unmarshaller unmarshaller4Body = jaxbCxt4Body.createUnmarshaller();
             BatchSyncOrderRelationReq batchSyncOrderRelationReq = (BatchSyncOrderRelationReq) unmarshaller4Body.unmarshal(new StringReader(head.getSvcCont().trim()));
             batchSyncOrderRelationReq.setHead(head);
             return batchSyncOrderRelationReq;
         } catch (JAXBException e) {
             throw new BusinessException("SyncOrderRelationReq.Deserialized() Error!(" + interBossXmlContent + ")", e);
         }
     }
 }

@XmlAccessorType(XmlAccessType.FIELD)


代码如下:

public class BatchSyncOrderRelationReqBody {
  @XmlElement(name = "oprNumb")
  private String oprNumb = "";
  @XmlElement(name = "subscriptionInfo")
  private SubscriptionInfo subscriptionInfo;
  public BatchSyncOrderRelationReqBody(){
  }
  public BatchSyncOrderRelationReqBody(String oprNumb, SubscriptionInfo subscriptionInfo) {
      this.oprNumb = oprNumb;
      this.subscriptionInfo = subscriptionInfo;
  }
  public String getOprNumb() {
      return this.oprNumb;
  }
  public void setOprNumb(String oprNumb) {
      this.oprNumb = oprNumb;
  }
  public SubscriptionInfo getSubscriptionInfo() {
      return this.subscriptionInfo;
  }
  public void setSubscriptionInfo(SubscriptionInfo subscriptionInfo) {
      this.subscriptionInfo = subscriptionInfo;
  }
}

@XmlAccessorType(XmlAccessType.FIELD)


代码如下:

public class SubscriptionInfo {
  @XmlElement(name = "oprTime")
  private String oprTime = "";
  @XmlElement(name = "actionID")
  private String actionId = "";
  @XmlElement(name = "brand")
  private String brand = "";
  @XmlElement(name = "effTime")
  private String effTime = "";
  @XmlElement(name = "expireTime")
  private String expireTime = "";
  @XmlElement(name = "feeUser_ID")
  private String feeUserId = "";
  @XmlElement(name = "destUser_ID")
  private String destUserId = "";
  @XmlElement(name = "actionReasonID")
  private String actionReasonId = "";
  @XmlElement(name = "servType")
  private String servType = "";
  @XmlElement(name = "subServType")
  private String subServType = "";
  @XmlElement(name = "SPID")
  private String spId = "";
  @XmlElement(name = "SPServID")
  private String spServId = "";
  @XmlElement(name = "accessMode")
  private String accessMode = "";
  @XmlElement(name = "feeType")
  private String feeType = "";
  public SubscriptionInfo() {
  }
  public SubscriptionInfo(
          String oprTime,
          String actionId,
          String brand,
          String effTime,
          String expireTime,
          String feeUserId,
          String destUserId,
          String actionReasonId,
          String servType,
          String subServType,
          String spId,
          String spServId,
          String accessMode,
          String feeType) {
      this.oprTime = oprTime;
      this.actionId = actionId;
      this.brand = brand;
      this.effTime = effTime;
      this.expireTime = expireTime;
      this.feeUserId = feeUserId;
      this.destUserId = destUserId;
      this.actionReasonId = actionReasonId;
      this.servType = servType;
      this.subServType = subServType;
      this.spId = spId;
      this.spServId = spServId;
      this.accessMode = accessMode;
      this.feeType = feeType;
  }
  public String getOprTime() {
      return this.oprTime;
  }
  public void setOprTime(String oprTime) {
      this.oprTime = oprTime;
  }
  public String getActionId() {
      return this.actionId;
  }
  public void setActionId(String actionId) {
      this.actionId = actionId;
  }
  public String getBrand() {
      return this.brand;
  }
  public void setBrand(String brand) {
      this.brand = brand;
  }
  public String getEffTime() {
      return this.effTime;
  }
  public void setEffTime(String effTime) {
      this.effTime = effTime;
  }
  public String getExpireTime() {
      return this.expireTime;
  }
  public void setExpireTime(String expireTime) {
      this.expireTime = expireTime;
  }
  public String getFeeUserId() {
      return this.feeUserId;
  }
  public void setFeeUserId(String feeUserId) {
      this.feeUserId = feeUserId;
  }
  public String getDestUserId() {
      return this.destUserId;
  }
  public void setDestUserId(String destUserId) {
      this.destUserId = destUserId;
  }
  public String getActionReasonId() {
      return this.actionReasonId;
  }
  public void setActionReasonId(String actionReasonId) {
      this.actionReasonId = actionReasonId;
  }
  public String getServType() {
      return this.servType;
  }
  public void setServType(String servType) {
      this.servType = servType;
  }
  public String getSubServType() {
      return this.subServType;
  }
  public void setSubServType(String subServType) {
      this.subServType = subServType;
  }
  public String getSpId() {
      return this.spId;
  }
  public void setSpId(String spId) {
      this.spId = spId;
  }
  public String getSpServId() {
      return this.spServId;
  }
  public void setSpServId(String spServId) {
      this.spServId = spServId;
  }
  public String getAccessMode() {
      return this.accessMode;
  }
  public void setAccessMode(String accessMode) {
      this.accessMode = accessMode;
  }
  public String getFeeType() {
      return this.feeType;
  }
  public void setFeeType(String feeType) {
      this.feeType = feeType;
  }
}