Heim >Backend-Entwicklung >XML/RSS-Tutorial >Ausführliche Erläuterung von Beispielen für zwei Probleme beim Zusammenführen von XML in der Android-Entwicklung
方法一:Dom4J处理XML
import java.io.File; import java.io.FileInputStream; import java.io.FileNotFoundException; import java.io.FileWriter; import java.io.IOException; import java.io.InputStream; import org.dom4j.Document; import org.dom4j.DocumentException; import org.dom4j.Element; import org.dom4j.io.SAXReader; import org.dom4j.io.XMLWriter; * 合并并输出2个xml文档,所需要jar:dom4j-1.6.1.jar,jaxen-1.1.1.jar * 将某个xml文档的某个标签下或该标签上一级下所有内容插入到另一个xml文档的某个标签下 * @date 2011-04-13 * @author RobotJi * @version 1.0 public class UniteXML { public UniteXML() {} * 根据is获取doc,这里的is可以是本地流或者网络流 * @param is * @return public static Document getDocument(InputStream is){ Document doc=null; try { doc=new SAXReader().read(is); } catch (DocumentException e) { e.printStackTrace(); } return doc; } public static InputStream getInputStream(String path){ File f=new File(path); if(!f.exists()){ return null; } InputStream is=null; try { is = new FileInputStream(f); } catch (FileNotFoundException e) { e.printStackTrace(); } return is; } * 获取子Element * @param doc 要获取的文档 * @param tagName 文档对应的标签 * @return public Element getSubElement(Document doc,String tagName){ Element el=(Element)doc.selectSingleNode("//"+tagName); return el; } * 输出xml文档 * @param doc 要输出的文档 * @param fileName 路径 public void writeXML(Document doc,String fileName){ try { XMLWriter writer=new XMLWriter(new FileWriter(fileName)); writer.write(doc); writer.flush(); writer.close(); } catch (IOException e) { e.printStackTrace(); } } * 合并doc * @param path1 主文档 * @param path2 被合并的文档 * @param tagName1 在主文档中要插入的标签 * @param tagName2 被合并文档的标签 * @param isContain 是否包含被合并文档标签的上一级标签下的所有结点 * @return public Document unitXMl(String path1,String path2,String tagName1,String tagName2,boolean isContain){ Document doc1=getDocument(getInputStream(path1)); Document doc2=getDocument(getInputStream(path2)); Element elSub2=getSubElement(doc2,tagName2); Element elSub1=getSubElement(doc1,tagName1); if(isContain){ // doc1.getRootElement().appendContent(elSub2.getParent());//直接插入的根标签下 elSub1.appendContent(elSub2.getParent());//插入到tagName1标签下 }else{ // doc1.getRootElement().appendContent(elSub2); elSub1.appendContent(elSub2); } return doc1; } public static void main(String[] args) { UniteXML ux=new UniteXML(); //将c标签下所有内容插入到aa标签下,若参数设为true则可将c标签上一级下的所有内容插入到aa标签下 Document doc=ux.unitXMl("F:\\test\\a.xml", "F:\\test\\b.xml", "aa", "c", false); ux.writeXML(doc, "F:\\test\\a_test.xml"); } }
//测试用的2个xml如下:
a.xml
方法二:
import java.io. *; //Java基础包,包含各种IO操作 import java.util. *; //Java基础包,包含各种标准数据结构操作 import javax.xml.parsers. *; //XML解析器接口 import org.w3c.dom. *; //XML的DOM实现 import javax.xml.transform. *; import javax.xml.transform.dom. *; import javax.xml.transform.stream. *; /** * XML文件合并工具类 * @author GhostFromHeaven */ public class XMLMergeUtil { /** * XML文件的合并处理 * @param mainFileName 待合并处理的xml文件,合并后将更新此文件 * @param subFilename 被合并的xml文件 * @return 合并成功返回true,否则返回false * @throws Exception */ public static boolean isMerging(String mainFileName, String subFilename) throws Exception { DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance(); DocumentBuilder db = null; try { db = dbf.newDocumentBuilder(); } catch (ParserConfigurationException pce) { System.err.println(pce); // 出现异常时,输出异常信息 } Document doc_main = null; Document doc_vice = null; // 获取两个XML文件的Document try { doc_main = db.parse(mainFileName); doc_vice = db.parse(subFilename); } catch (DOMException dom) { System.err.println(dom.getMessage()); } catch (Exception ioe) { System.err.println(ioe); } // 获取两个文件的根节点 Element root_main = doc_main.getDocumentElement(); Element root_vice = doc_vice.getDocumentElement(); // 下面添加被合并文件根节点下的每个节点 NodeList messageItems = root_vice.getChildNodes(); int item_number = messageItems.getLength(); // 如果去掉根节点下的第一个节点,那么i从3开始,否则i从1开始 for (int i = 1; i < item_number; i = i + 2) { // 调用dupliate(),依次复制被合并XML文档中根节点下的节点 Element messageItem = (Element) messageItems.item(i); dupliate(doc_main, root_main, messageItem); } // 调用 write To(),将合并得到的Document写入目标XML文档 boolean isWritten = writeTo(doc_main, mainFileName); return isWritten; } /** * * @param doc_dup * @param father * @param son * @return * @throws Exception */ private static boolean dupliate(Document doc_dup, Element father, Element son) throws Exception { boolean isdone = false; Element parentElement = null; DuplicateChildElementObject childElementObject = isChildElement(father, son); if(!childElementObject.isNeedDuplicate()){ //节点相同不用合并 isdone = true; parentElement = childElementObject.getElement(); }else if(childElementObject.getElement() != null){ parentElement = childElementObject.getElement(); }else{ parentElement = father; } String son_name = son.getNodeName(); Element subITEM = null; if(!isdone){ subITEM = doc_dup.createElement(son_name); // 复制节点的属性 if (son.hasAttributes()) { NamedNodeMap attributes = son.getAttributes(); for (int i = 0; i < attributes.getLength(); i++) { String attribute_name = attributes.item(i).getNodeName(); String attribute_value = attributes.item(i).getNodeValue(); subITEM.setAttribute(attribute_name, attribute_value); } } parentElement.appendChild(subITEM); } else{ subITEM = parentElement; } // 复制子结点 NodeList sub_messageItems = son.getChildNodes(); int sub_item_number = sub_messageItems.getLength(); if (sub_item_number < 2) { // 如果没有子节点,则返回 isdone = true; } else { for (int j = 1; j < sub_item_number; j = j + 2) { // 如果有子节点,则递归调用本方法 Element sub_messageItem = (Element) sub_messageItems.item(j); isdone = dupliate(doc_dup, subITEM, sub_messageItem); } } return isdone; } private static boolean writeTo(Document doc, String fileName) throws Exception { boolean isOver = false; DOMSource doms = new DOMSource(doc); File f = new File(fileName); StreamResult sr = new StreamResult(f); try { TransformerFactory tf = TransformerFactory.newInstance(); Transformer t = tf.newTransformer(); Properties properties = t.getOutputProperties(); properties.setProperty(OutputKeys.ENCODING, "UTF-8"); t.setOutputProperties(properties); t.transform(doms, sr); isOver = true; } catch (TransformerConfigurationException tce) { tce.printStackTrace(); } catch (TransformerException te) { te.printStackTrace(); } return isOver; } private static DuplicateChildElementObject isChildElement(Element father, Element son){ DuplicateChildElementObject childElementObject = new DuplicateChildElementObject(); NodeList messageItems = father.getChildNodes(); int item_number = messageItems.getLength(); //首先遍历所有节点,查找是否有完全相同的节点,防止同一节点已定义多次 for (int i = 1; i < item_number; i = i + 2) { Element messageItem = (Element) messageItems.item(i); if(!messageItem.getNodeName().equals(son.getNodeName())){ continue; } if(messageItem.isEqualNode(son)){//同时判断子节点是否一致 childElementObject.setNeedDuplicate(false); childElementObject.setElement(messageItem); return childElementObject; } } for (int i = 1; i < item_number; i = i + 2) { Element messageItem = (Element) messageItems.item(i); //判断节点是否处于同一级别 if(!messageItem.getNodeName().equals(son.getNodeName())){ continue; } if(isEqualNode(messageItem,son)){//仅判断当前节点是否一致 if(hasEqualAttributes(messageItem,son)){//当前节点完全相同不需要合并 childElementObject.setNeedDuplicate(false); childElementObject.setElement(messageItem); return childElementObject; }else{//当前节点的属性不相同,需要合并 childElementObject.setNeedDuplicate(true); childElementObject.setElement(father); return childElementObject; } } } //目标文档该节点不存在,需要合并到目标文档中 childElementObject.setNeedDuplicate(true); childElementObject.setElement(father); return childElementObject; } /** * 判断两个节点是否相同,未判断节点的属性 * @param arg0 * @param arg * @return */ private static boolean isEqualNode(Node arg0,Node arg) { if (arg == arg0) { return true; } if (arg.getNodeType() != arg0.getNodeType()) { return false; } if (arg0.getNodeName() == null) { if (arg.getNodeName() != null) { return false; } } else if (!arg0.getNodeName().equals(arg.getNodeName())) { return false; } if (arg0.getLocalName() == null) { if (arg.getLocalName() != null) { return false; } } else if (!arg0.getLocalName().equals(arg.getLocalName())) { return false; } if (arg0.getNamespaceURI() == null) { if (arg.getNamespaceURI() != null) { return false; } } else if (!arg0.getNamespaceURI().equals(arg.getNamespaceURI())) { return false; } if (arg0.getPrefix() == null) { if (arg.getPrefix() != null) { return false; } } else if (!arg0.getPrefix().equals(arg.getPrefix())) { return false; } if (arg0.getNodeValue() == null) { if (arg.getNodeValue() != null) { return false; } } else if (!arg0.getNodeValue().equals(arg.getNodeValue())) { return false; } return true; } /** * 判断节点的属性是否相同 * @param arg0 * @param arg * @return */ private static boolean hasEqualAttributes(Node arg0,Node arg) { NamedNodeMap map1 = arg0.getAttributes(); NamedNodeMap map2 = arg.getAttributes(); int len = map1.getLength(); if (len != map2.getLength()) { return false; } for (int i = 0; i < len; i++) { Node n1 = map1.item(i); if(n1.getNodeName() != null){ Node n2 = map2.getNamedItem(n1.getNodeName()); if(n2 == null){ return false; }else if(!n1.getNodeValue().equals(n2.getNodeValue())){ return false; } } } return true; } public static void main(String[] args) { try { String sourcefile = "d:/a.xml"; String targetfile = "d:/b.xml"; boolean isdone = XMLMergeUtil.isMerging(sourcefile, targetfile); if (isdone) System.out.println("XML files have been merged."); else System.out.println("XML files have NOT been merged."); } catch (Exception e) { e.printStackTrace(); } } } /** * 复制子节点对象 * @author Administrator * */ class DuplicateChildElementObject{ private boolean needDuplicate = true;//记录该节点是否需要复制 private Element element = null;//记录该节点的父节点 public DuplicateChildElementObject() { super(); } public boolean isNeedDuplicate() { return needDuplicate; } public void setNeedDuplicate(boolean needDuplicate) { this.needDuplicate = needDuplicate; } public Element getElement() { return element; } public void setElement(Element element) { this.element = element; } }
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