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JAVA操作XML文档主要有四种方式，分别是DOM、SAX、JDOM和DOM4J，DOM和SAX是官方提供的，而JDOM和DOM4J则是引用第三方库的，其中用的最多的是DOM4J方式。运行效率和内存使用方面最优的是SAX，但是由于SAX是基于事件的方式，所以SAX无法在编写XML的过程中对已编写内容进行修改，但对于不用进行频繁修改的需求，还是应该选择使用SAX。
下面基于这四种方式来读取XML文件。
第一，以DOM的方式实现。
package xmls;import org.w3c.dom.Document;import org.w3c.dom.Element;import org.w3c.dom.Node;import org.w3c.dom.NodeList;import org.xml.sax.SAXException;import javax.xml.parsers.DocumentBuilder;import javax.xml.parsers.DocumentBuilderFactory;import javax.xml.parsers.ParserConfigurationException;import java.io.File;import java.io.IOException;/** * Created by lenovo on 2017-6-3. */public class DOMReadDemo { public static void main(String[] args){ DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance(); try{ DocumentBuilder db = dbf.newDocumentBuilder(); Document document = db.parse("src/xmls/DOM.xml"); NodeList booklist = document.getElementsByTagName("book"); for(int i = 0; i < booklist.getLength(); i++){ System.out.println("--------第" + (i+1) + "本书----------"); Element ele = (Element) booklist.item(i); NodeList childNodes= ele.getChildNodes(); for(int j = 0; j < childNodes.getLength(); j++){ Node n = childNodes.item(j); if(n.getNodeName() != "#text"){ System.out.println(n.getNodeName() + ":" + n.getTextContent()); } } System.out.println("---------------------------------"); } }catch (ParserConfigurationException e){ e.printStackTrace(); }catch (IOException e){ e.printStackTrace(); }catch (SAXException e){ e.printStackTrace(); } }}第二，以SAX的方式实现。
package xmls;import javax.xml.parsers.SAXParser;import javax.xml.parsers.SAXParserFactory;/** * Created by lenovo on 2017-6-1. */public class xmlTest2 { public static void main(String[] args){ SAXParserFactory spf = SAXParserFactory.newInstance(); try{ SAXParser sp = spf.newSAXParser(); SAXParserHandler handler = new SAXParserHandler(); sp.parse("src\\xmls\\book.xml", handler); }catch (Exception e){ e.printStackTrace(); } }}package xmls;import org.xml.sax.Attributes;import org.xml.sax.SAXException;import org.xml.sax.helpers.DefaultHandler;/** * Created by lenovo on 2017-6-1. */public class SAXParserHandler extends DefaultHandler { @Override public void startDocument() throws SAXException { super.startDocument(); System.out.println("SAX解析开始"); } @Override public void endDocument() throws SAXException { super.endDocument(); System.out.println("SAX解析结束"); } @Override public void startElement(String s, String s1, String s2, Attributes attributes) throws SAXException { super.startElement(s, s1, s2, attributes); System.out.println(s2); for(int i = 0; i < attributes.getLength(); i++){ String name = attributes.getQName(i); String value = attributes.getValue(name); System.out.println("属性值：" + name + "=" + value); } } @Override public void endElement(String s, String s1, String s2) throws SAXException { super.endElement(s, s1, s2); if(s2.equals("book")){ System.out.println("-----------------------"); } } @Override public void characters(char[] ch, int start, int length) throws SAXException { super.characters(ch, start, length); String value = new String(ch, start, length); if(value.trim().equals("")){ return; } System.out.println(value); }}第三，以JDOM的方式实现。
package xmls;import org.jdom2.Attribute;import org.jdom2.Document;import org.jdom2.Element;import org.jdom2.JDOMException;import org.jdom2.input.JDOMParseException;import org.jdom2.input.SAXBuilder;import java.io.*;import java.util.List;/** * Created by lenovo on 2017-6-2. */public class JDOMTest { public static void main(String[] args){ SAXBuilder saxBuilder = new SAXBuilder(); InputStream in; try{ in = new FileInputStream(new File("src\\xmls\\book.xml")); Document document = saxBuilder.build(in); Element rootElement = document.getRootElement(); List<Element> bookList = rootElement.getChildren(); for(Element book: bookList){ System.out.println("第" + (bookList.indexOf(book)+1) + "本书！"); List<Attribute> attrs = book.getAttributes(); for(Attribute attr: attrs){ System.out.println(attr.getName() + "=" + attr.getValue()); } for(Element item: book.getChildren()){ System.out.println(item.getName() + ":" + item.getValue()); } System.out.println("------------------------------------"); } }catch (FileNotFoundException e){ e.printStackTrace(); }catch (JDOMException e){ e.printStackTrace(); }catch (IOException e){ e.printStackTrace(); } }}第四，以DOM4J的方式实现。
package xmls;import org.dom4j.*;import org.dom4j.io.OutputFormat;import org.dom4j.io.SAXReader;import org.dom4j.io.XMLWriter;import java.io.File;import java.io.FileOutputStream;import java.io.IOException;import java.util.Iterator;import java.util.List;/** * Created by lenovo on 2017-6-2. */public class DOM4JTest { public void parseXML(){ SAXReader saxReader = new SAXReader(); try{ Document document = saxReader.read(new File("src\\xmls\\book.xml")); Element rootElement = document.getRootElement(); Iterator it = rootElement.elementIterator(); while (it.hasNext()){ Element book = (Element)it.next(); List<Attribute> attrs = book.attributes(); for(Attribute attr: attrs){ System.out.println("属性名：" + attr.getName() + "---- 属性值：" + attr.getValue() ); } Iterator cit = book.elementIterator(); while (cit.hasNext()){ Element child = (Element) cit.next(); System.out.println("子节点：" + child.getName()); } } }catch (DocumentException e){ e.printStackTrace(); } } public static void main(String[] args){ DOM4JTest dom4JTest = new DOM4JTest(); dom4JTest.parseXML(); }}以上这篇java读取XML文件的四种方法总结(必看篇)就是小编分享给大家的全部内容了，希望能给大家一个参考，。
关键词： java读取XML文件
