使用dom输出一个xml文件中的内容
1 import java.io.File; 2 import java.io.IOException; 3 4 import javax.xml.parsers.DocumentBuilder; 5 import javax.xml.parsers.DocumentBuilderFactory; 6 import javax.xml.parsers.ParserConfigurationException; 7 8 import org.w3c.dom.Document; 9 import org.w3c.dom.NodeList; 10 import org.xml.sax.SAXException; 11 12 public class dom{ 13 public static void main(String args[]){ 14 15 16 //取得DocumentBuilderFactory类的对象 17 DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance(); 18 //取得DocumentBuilder类的对象 19 try { 20 DocumentBuilder builder = factory.newDocumentBuilder(); 21 22 Document doc =builder.parse(new File("src//dom.xml")); 23 NodeList list = doc.getElementsByTagName("name"); 24 //输出节点 25 System.out.println("姓名 : " + list.item(0).getFirstChild().getNodeValue()); 26 27 } catch (ParserConfigurationException e) { 28 e.printStackTrace(); 29 } catch (SAXException e) { 30 e.printStackTrace(); 31 } catch (IOException e) { 32 e.printStackTrace(); 33 } 34 35 36 37 38 39 } 40 }
此为上述使用的xml
1 <?xml version="1.0" encoding="GBK"?> 2 <addresslist> 3 <name>张浩威</name> 4 </addresslist>
1 输出结果 2 3 4 5 6 姓名 : 张浩威
较为复杂的xml文件可以用循环访问
1 import java.io.File; 2 import java.io.IOException; 3 4 5 import javax.xml.parsers.DocumentBuilder; 6 import javax.xml.parsers.DocumentBuilderFactory; 7 import javax.xml.parsers.ParserConfigurationException; 8 9 import org.w3c.dom.Document; 10 import org.w3c.dom.Element; 11 import org.w3c.dom.NodeList; 12 import org.xml.sax.SAXException; 13 14 public class dom2{ 15 public static void main(String args[]){ 16 17 18 //取得DocumentBuilderFactory类的对象 19 DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance(); 20 //取得DocumentBuilder类的对象 21 try { 22 DocumentBuilder builder = factory.newDocumentBuilder(); 23 24 Document doc =builder.parse(new File("src//dom1.xml")); 25 26 //得到所有linkman的节点 27 NodeList list = doc.getElementsByTagName("listman"); 28 //输出节点 29 for(int i = 0 ; i < list.getLength() ; i++ ){ 30 31 Element e = (Element)list.item(i); 32 System.out.println("姓名 : " + e.getElementsByTagName("name").item(0).getFirstChild().getNodeValue()); 33 System.out.println("邮箱 : " + e.getElementsByTagName("email").item(0).getFirstChild().getNodeValue()); 34 } 35 } catch (ParserConfigurationException e) { 36 e.printStackTrace(); 37 } catch (SAXException e) { 38 e.printStackTrace(); 39 } catch (IOException e) { 40 e.printStackTrace(); 41 } 42 43 44 45 46 47 } 48 }
1 <?xml version="1.0" encoding="GBK"?> 2 <addresslist> 3 <listman> 4 <name>张浩威</name> 5 <email>287877150@qq.com</email> 6 </listman> 7 <listman> 8 <name>张浩龙</name> 9 <email>94397959@qq.com</email> 10 </listman> 11 </addresslist>
1 输出结果: 2 3 4 5 姓名 : 张浩威 6 邮箱 : 287877150@qq.com 7 姓名 : 张浩龙 8 邮箱 : 94397959@qq.com
也可以用dom来生成xml文件
1 import java.io.File; 2 import java.io.IOException; 3 4 5 import javax.xml.parsers.DocumentBuilder; 6 import javax.xml.parsers.DocumentBuilderFactory; 7 import javax.xml.parsers.ParserConfigurationException; 8 import javax.xml.transform.OutputKeys; 9 import javax.xml.transform.Transformer; 10 import javax.xml.transform.TransformerConfigurationException; 11 import javax.xml.transform.TransformerException; 12 import javax.xml.transform.TransformerFactory; 13 import javax.xml.transform.dom.DOMSource; 14 import javax.xml.transform.stream.StreamResult; 15 16 import org.w3c.dom.Document; 17 import org.w3c.dom.Element; 18 import org.w3c.dom.NodeList; 19 import org.xml.sax.SAXException; 20 21 22 //Dom操作除了可以进行解析之外还可以进行文件的生成 23 public class dom3{ 24 public static void main(String args[]){ 25 26 27 //取得DocumentBuilderFactory类的对象 28 DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance(); 29 //取得DocumentBuilder类的对象 30 try { 31 DocumentBuilder builder = factory.newDocumentBuilder(); 32 33 //创建一个新的xml文档 34 Document doc =builder.newDocument(); 35 Element addresslist = doc.createElement("addresslist"); 36 Element listman = doc.createElement("listman"); 37 Element name = doc.createElement("name"); 38 Element email = doc.createElement("email"); 39 40 //设置节点内容 41 name.appendChild(doc.createTextNode("张浩威")); 42 email.appendChild(doc.createTextNode("287877150@qq.com")); 43 //设置各节点的关系 44 //将节点name 和 email设置为listman的子节点 45 listman.appendChild(name); 46 listman.appendChild(email); 47 //将listman设置为addresslist的子节点 48 addresslist.appendChild(listman); 49 //设置根节点 50 doc.appendChild(addresslist); 51 52 //得到所有linkman的节点 53 NodeList list = doc.getElementsByTagName("listman"); 54 //这段代码的关键是将文档内容保存在文件中 55 TransformerFactory tf = TransformerFactory.newInstance(); 56 Transformer transformer = tf.newTransformer(); 57 //设置输出编码 58 transformer.setOutputProperty(OutputKeys.ENCODING, "GBK"); 59 //准备输出文档 60 DOMSource source = new DOMSource(doc); 61 StreamResult result = new StreamResult(new File("dom2.xml")); 62 transformer.transform(source, result); 63 64 65 } catch (ParserConfigurationException e) { 66 e.printStackTrace(); 67 } catch (TransformerConfigurationException e) { 68 e.printStackTrace(); 69 } catch (TransformerException e) { 70 e.printStackTrace(); 71 } 72 73 74 //此时可以完成文档的输出操作,但是输出后的xml文档格式非常不好 75 //对于dom操作既可以读取也可以输出和修改,更多的操作在于读取 76 77 78 } 79 }
1 输出结果 2 格式很难看,但是符合标准 3 <?xml version="1.0" encoding="GBK" standalone="no"?><addresslist><listman><name>张浩威</name><email>287877150@qq.com</email></listman></addresslist>
