但其操作起来并不轻松，对于我这么一个初学者来说，其中部分代码是活生生的恶心
为此，伟大的第三方开发组开发出了jdom和dom4j等工具
鉴于目前的趋势，我们这里来讲讲dom4j的基本用法，不涉及递归等复杂操作
dom4j的用法很多，官网上的示例有那么点儿晦涩，这里就不写了
首先我们需要出创建一个xml文档，然后才能对其解析
xml文档：
<?xml version="1.0" encoding="utf-8"?> <books> <book id="001"> <title>harry potter</title> <author>j k. rowling</author> </book> <book id="002"> <title>learning xml</title> <author>erik t. ray</author> </book> </books>
示例一：用list列表的方式来解析xml
import java.io.file; import java.util.list; import org.dom4j.attribute; import org.dom4j.document; import org.dom4j.element; import org.dom4j.io.saxreader; public class demo { public static void main(string[] args) throws exception { saxreader reader = new saxreader(); file file = new file("books.xml"); document document = reader.read(file); element root = document.getrootelement(); list<element> childelements = root.elements(); for (element child : childelements) { //未知属性名情况下 /*list<attribute> attributelist = child.attributes(); for (attribute attr : attributelist) { system.out.println(attr.getname() + ": " + attr.getvalue()); }*/ //已知属性名情况下 system.out.println("id: " + child.attributevalue("id")); //未知子元素名情况下 /*list<element> elementlist = child.elements(); for (element ele : elementlist) { system.out.println(ele.getname() + ": " + ele.gettext()); } system.out.println();*/ //已知子元素名的情况下 system.out.println("title" + child.elementtext("title")); system.out.println("author" + child.elementtext("author")); //这行是为了格式化美观而存在 system.out.println(); } } }
示例二：使用iterator迭代器的方式来解析xml
import java.io.file; import java.util.iterator; import org.dom4j.attribute; import org.dom4j.document; import org.dom4j.element; import org.dom4j.io.saxreader; public class demo { public static void main(string[] args) throws exception { saxreader reader = new saxreader(); document document = reader.read(new file("books.xml")); element root = document.getrootelement(); iterator it = root.elementiterator(); while (it.hasnext()) { element element = (element) it.next(); //未知属性名称情况下 /*iterator attrit = element.attributeiterator(); while (attrit.hasnext()) { attribute a = (attribute) attrit.next(); system.out.println(a.getvalue()); }*/ //已知属性名称情况下 system.out.println("id: " + element.attributevalue("id")); //未知元素名情况下 /*iterator eleit = element.elementiterator(); while (eleit.hasnext()) { element e = (element) eleit.next(); system.out.println(e.getname() + ": " + e.gettext()); } system.out.println();*/ //已知元素名情况下 system.out.println("title: " + element.elementtext("title")); system.out.println("author: " + element.elementtext("author")); system.out.println(); } } }
运行结果：
示例三：创建xml文档并输出到文件
import java.io.file; import java.io.fileoutputstream; import org.dom4j.document; import org.dom4j.documenthelper; import org.dom4j.element; import org.dom4j.io.outputformat; import org.dom4j.io.xmlwriter; public class demo { public static void main(string[] args) throws exception { document doc = documenthelper.createdocument(); //增加根节点 element books = doc.addelement("books"); //增加子元素 element book1 = books.addelement("book"); element title1 = book1.addelement("title"); element author1 = book1.addelement("author"); element book2 = books.addelement("book"); element title2 = book2.addelement("title"); element author2 = book2.addelement("author"); //为子节点添加属性 book1.addattribute("id", "001"); //为元素添加内容 title1.settext("harry potter"); author1.settext("j k. rowling"); book2.addattribute("id", "002"); title2.settext("learning xml"); author2.settext("erik t. ray"); //实例化输出格式对象 outputformat format = outputformat.createprettyprint(); //设置输出编码 format.setencoding("utf-8"); //创建需要写入的file对象 file file = new file("d:" + file.separator + "books.xml"); //生成xmlwriter对象，构造函数中的参数为需要输出的文件流和格式 xmlwriter writer = new xmlwriter(new fileoutputstream(file), format); //开始写入，write方法中包含上面创建的document对象 writer.write(doc); } }
运行结果：
更多在java中使用dom4j解析xml(示例代码)。