ajax、jsp、dom4j

这篇文章跟上一篇，做了一些大的改动，主要是xml创建改用dom4j,用反射知识支持更多的javaBean

ok,不再废话，上代码

 

• 1.js代码不同之处：

 

原代码：var stuList = stuDom.getElementsByTagName("student");

 

修改之后为：var stuList = stuDom.getElementsByTagName("childNode");

 

•  2.servlet代码：

• public class InfoServlet extends HttpServlet {
  	private static final long serialVersionUID = 1L;
  	public void doGet(HttpServletRequest request, HttpServletResponse response)
  			throws ServletException, IOException {
  		//------------------通用方法使用dom4j框架--------------------------------------
  		response.setCharacterEncoding("utf-8");
  		response.setContentType("application/xml");
  		PrintWriter out = response.getWriter();
  		List<Student>list = new QueryStu().getStu();
  		WriteXmlUtil.write(out,list,"bean.Student");
  	}
  
  	public void doPost(HttpServletRequest request, HttpServletResponse response)
  			throws ServletException, IOException {
  		doGet(request, response);
  	}
  
  }
  

   
• 3.WriteXmlUtil类,这个是修改的关键之处

• package xmlUtil;
  
  import java.io.IOException;
  import java.io.PrintWriter;
  import java.lang.reflect.InvocationTargetException;
  import java.lang.reflect.Method;
  import java.util.ArrayList;
  import java.util.List;
  
  import org.dom4j.Document;
  import org.dom4j.DocumentHelper;
  import org.dom4j.Element;
  import org.dom4j.io.OutputFormat;
  import org.dom4j.io.XMLWriter;
  
  public class WriteXmlUtil {
  
  	public static <T> void write(PrintWriter out, List<T> list, String beanName) {
  		// -----------取得beanName的get方法--------------------------
  		Class<?> clazz = null;
  		try {
  			clazz = Class.forName(beanName);
  		} catch (ClassNotFoundException e1) {
  			e1.printStackTrace();
  		}
  		Method methods[] = clazz.getMethods();
  		List<Method> mGetList = new ArrayList<Method>();// javaBean类的全部get方法
  		for (int i = 0; i < methods.length; i++) {
  			int flag = methods[i].getName().indexOf("get");
  			if (flag != -1) {
  				mGetList.add(methods[i]);
  			}
  		}
  		mGetList.remove(mGetList.size() - 1);// 去掉getClass()方法
  		// ---------------------------------------------
  
  		Document document = DocumentHelper.createDocument();
  		Element root = DocumentHelper.createElement("root");
  		document.setRootElement(root);// 设为根节点
  		for (int i = 0; i < list.size(); i++) {
  			Element ele = root.addElement("childNode");// 子节点
  			for (int j = 0; j < mGetList.size(); j++) {
  				Object obj = list.get(i);
  				Element id = ele.addElement(mGetList.get(j).getName());
  				try {
  					Object value = mGetList.get(j).invoke(obj);//利用方法反射得到value数据
  					id.setText(value.toString());//设置文本
  				} catch (IllegalArgumentException e) {
  					e.printStackTrace();
  				} catch (IllegalAccessException e) {
  					e.printStackTrace();
  				} catch (InvocationTargetException e) {
  					e.printStackTrace();
  				}
  			}
  		}
  		OutputFormat format = new OutputFormat();
  		format.setEncoding("UTF-8");
  		XMLWriter writer = new XMLWriter(out, format);
  		try {
  			writer.write(document);
  			writer.close();
  		} catch (IOException e) {
  			e.printStackTrace();
  		}
  	}
  }
  

   ok,用到知识很碎，但是这个类通用性很高，只要从数据库获取到一个list数据，还有对应的javaBean类，那么就可以生成对应的xml文件，并加到out对象反馈给客户端