将XML结点转换成JAVABEAN并存入数据库
http://tech.ddvip.com 2007年07月03日 社区交流
内容摘要：动解析的过程中，我们仍然发现各个结点的解析和入库中有很多东西是共同的，或者有共同的规律，这些东西可以抽出来作为一个准框架，然后再将结点中不同的部分开放出来，允许具体的结点做具体的实现，并最终形成一个半自动的解析/入库框架。
b.默认的实现
import java.lang.reflect.Field;
import java.util.*;
import org.apache.commons.beanutils.PropertyUtils;
import org.dom4j.Attribute;
import org.dom4j.Element;
/**
* 默认的BUSI NODE。 继承此类的BUSI NODE 需满足 所有不可分属性集=String类型的属性集
* MyUtils类的代码欠奉
*
*/
public abstract class DefaultBusiNode implements BusiNode {
public List getAtomicPropNames() {
return MyUtils.getFieldNamesOfClass(this.getClass(), String.class);
}
public List getBusiNodePropNames() {
return MyUtils.getFieldNamesOfClass(this.getClass(), BusiNode.class);
}
/*
* 所有子元素的父元素。有时是本结点，有时是本结点下的元素。变态
*/
public abstract Element getXmlElementParent(Element rootElement);
/*
* 类集子结点根元素的Iterator 。 假设一个pig有多个pighead，
* 那结构可能为 pig--pighead,pighead,...，
* 也可能为pig--pigheads--content,content....
* 必须让程序知道某个具体结点用的是哪种模式
*
* 如果为空则返回一个空类集的Iterator ，不要返回NULL
*/
public abstract Iterator getCollectionElementIterator(
Element xmlElementParent, String attName);
/**
* 解析XML属性
*
* @param rootElement
*/
protected void parseAttributesFromXml(Element rootElement) {
List xmlAttributes = this.getXmlAttributes();
for (int i = 0; i < this.getXmlAttributes().size(); i++) {
String attName = (String) xmlAttributes.get(i);
Attribute att = rootElement.attribute(attName);
if (att != null) {
try {
PropertyUtils.setProperty(this, attName, att.getValue());
} catch (Exception e) {
throw new RuntimeException(e);
}
}
}
}
/**
* 解析不可分的Element
*
* @param rootElement
*/
protected void parseAtomicElementFromXml(Element rootElement) {
Element xmlElementParent = getXmlElementParent(rootElement);
if (xmlElementParent == null) {
return;
}
List xmlElements = this.getXmlAtomicElements();
for (int i = 0; i < xmlElements.size(); i++) {
String attName = (String) xmlElements.get(i);
Element elmt = xmlElementParent.element(attName);
if (elmt != null) {
try {
PropertyUtils.setProperty(this, attName, elmt.getText());
} catch (Exception e) {
throw new RuntimeException(e);
}
}
}
}
/**
* 解析BusiNode属性
*
* @param rootElement
*/
protected void parseBusiNodeElementFromXml(Element rootElement) {
Element xmlElementParent = getXmlElementParent(rootElement);
if (xmlElementParent == null) {
return;
}
// 再解析BusiNode属性
List busiNodePropNames = this.getBusiNodePropNames();
for (int i = 0; i < busiNodePropNames.size(); i++) {
try {
String attName = (String) busiNodePropNames.get(i);
Element elmt = xmlElementParent.element(attName);
if (elmt != null) {
Field field = this.getClass().getDeclaredField(attName);
BusiNode att = (BusiNode) field.getType().newInstance();
att.parseFromXML(elmt);
PropertyUtils.setProperty(this, attName, att);
}
} catch (Exception e) {
throw new RuntimeException(e);
}
}
}
/**
* 解析类集属性
*
* @param rootElement
*/
protected void parseCollectionPropsFromXml(Element rootElement) {
// 先解析XML属性
Element xmlElementParent = getXmlElementParent(rootElement);
if (xmlElementParent == null) {
return;
}
// 最后解析类集属性
Map collectionPropsMap = this.getCollectionPropsMap();
for (Iterator it = collectionPropsMap.keySet().iterator(); it.hasNext();) {
try {
String attName = (String) it.next();
Collection coll = (Collection) PropertyUtils.getProperty(this,
attName);
Class attType = (Class) collectionPropsMap.get(attName);
Iterator collElementsIt = this.getCollectionElementIterator(
xmlElementParent, attName);
// xmlElementParent.elementIterator(attName);
while (collElementsIt.hasNext()) {
Element collElmt = (Element) collElementsIt.next();
BusiNode sinlgeAtt = (BusiNode) attType.newInstance();
sinlgeAtt.parseFromXML(collElmt);
coll.add(sinlgeAtt);
}
} catch (Exception e) {
throw new RuntimeException(e);
}
}
}
/**
* 从XML中解析出结点。此方法可能抛出RumtimeException
*/
public void parseFromXML(Element rootElement) {
this.parseAttributesFromXml(rootElement);
this.parseAtomicElementFromXml(rootElement);
this.parseBusiNodeElementFromXml(rootElement);
this.parseCollectionPropsFromXml(rootElement);
}
}
/**
* 入库
* JdbcUtil,MyUtils的代码欠奉
*
*/
public class BusiNodeDAO {
private Long saveBusiNode(BusiNode node, Long parentNodeId) {
// 先存储原子属性
Long id = saveBareBusiNode(node, parentNodeId);
// 再存储类集属性
Map collectionPropsMap = node.getCollectionPropsMap();
for (Iterator it = collectionPropsMap.keySet().iterator(); it.hasNext();) {
String attName = (String) it.next();
Collection coll = null;
try {
coll = (Collection) PropertyUtils.getProperty(node, attName);
} catch (Exception e) {
throw new RuntimeException("编码错误");
}
for (Iterator iitt = coll.iterator(); iitt.hasNext();) {
BusiNode subNode = (BusiNode) iitt.next();
saveBusiNode(subNode, id);
}
}
// 最后存储所有BusiNode属性
Iterator iitt = node.getBusiNodePropNames().iterator();
while (iitt.hasNext()) {
BusiNode subNode = null;
try {
subNode = (BusiNode) PropertyUtils.getProperty(node,
(String) iitt.next());
} catch (Exception e) {
throw new RuntimeException("编码错误");
}
if (subNode != null) {
saveBusiNode(subNode, id);
}
}
return id;
}
/**
* 插入某个BusiNode的根结点，此方法可能抛出RuntimeException
*
* @param node
* @return
*/
private Long saveBareBusiNode(BusiNode node, Long parentNodeId) {
StringBuffer sbForSql = new StringBuffer();
List paramValues = new ArrayList();
genInsertSqlAndParam(node, parentNodeId, node.getAtomicPropNames(),
sbForSql, paramValues);
return new Long(JdbcUtil.queryForLong(
sbForSql.toString(), paramValues.toArray()));
}
/**
* 生成某个结点的插入语句和paramValues数组，此方法可能抛出RuntimeException
*
* @param node
* @param columnNames
* @param sbForSql
* @param paramValues
*/
private void genInsertSqlAndParam(BusiNode node, Long parentNodeId,
List columnNames, StringBuffer sbForSql, List paramValues) {
sbForSql.append(" insert into ");
sbForSql.append(MyUtils.getClassBareName(node.getClass()));
List cns = new ArrayList();
cns.addAll(columnNames);
cns.add("parentNodeId");
sbForSql.append(MyUtils.encloseWithCurve(MyUtils
.joinCollectionStrings(cns, ",")));
sbForSql.append(" values ");
List qms = new ArrayList(); // 问号
for (Iterator it = columnNames.iterator(); it.hasNext();) {
qms.add("?");
String cn = (String) it.next();
try {
paramValues.add(PropertyUtils.getProperty(node, cn));
} catch (Exception e) {
throw new RuntimeException(e);
}
}
qms.add("?"); // parentNodeId
paramValues.add(parentNodeId);
sbForSql.append(MyUtils.encloseWithCurve(MyUtil
.joinCollectionStrings(qms, ",")));
sbForSql.append(";select @@identity");
}
}
责编：豆豆技术应用
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