课程JSP中用户注册登录界面，需配合数据库一起使用。非常简单的一个登录注册与检测界面。

import java.io.IOException;
import java.io.PrintWriter;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

@WebServlet（urlPatterns=“/login.do“）
public class HelloServlet extends HttpServlet{

	@Override
	protected void service（HttpServletRequest req HttpServletResponse resp）
			throws ServletException IOException {
		
		resp.setContentType（“text/html;charset=utf8“）;
		PrintWriter out = resp.getWriter（）;
		
		String name = req.getParameter（“username“）;
		String pass = req.getParameter（“pass“）;
		if（name.equals（“张“）&&pass.equals（“123“））
		{
			out.println（“
你好“+ name + “!
“）;
			out.println（““

 属性            大小     日期    时间   名称
----------- ---------  ---------- -----  ----
     文件        1143  2014-06-11 01:21  hello\build\classes\cn\jhc\service\test.class
     文件        1176  2014-06-11 01:21  hello\build\classes\cn\jhc\service\UDPSe.class
     文件        1576  2014-06-11 01:21  hello\build\classes\cn\jhc\service\TotalServlet.class
     文件        2114  2014-06-11 01:21  hello\build\classes\cn\jhc\service\SurveryServlet.class
     文件        6301  2014-06-11 01:21  hello\build\classes\cn\jhc\service\SurveryService.class
     文件         799  2014-06-11 01:21  hello\build\classes\cn\jhc\service\SurveryService$SexCount.class
     文件        1557  2014-06-11 01:21  hello\build\classes\cn\jhc\service\ShowAddUserFormServlet.class
     文件        2120  2014-06-11 01:21  hello\build\classes\cn\jhc\service\LoadGroupsServlet.class
     文件        1274  2014-06-11 01:21  hello\build\classes\cn\jhc\bean\User.class
     文件         774  2014-06-11 01:21  hello\build\classes\cn\jhc\bean\Group.class
     文件         470  2014-04-28 03:17  hello\src\cn\jhc\bean\Group.java
     文件         702  2014-04-28 03:17  hello\src\cn\jhc\bean\User.java
     文件        1474  2014-04-28 03:17  hello\src\cn\jhc\service\LoadGroupsServlet.java
     文件        1373  2014-04-28 03:17  hello\src\cn\jhc\service\ShowAddUserFormServlet.java
     文件        4824  2014-04-28 03:17  hello\src\cn\jhc\service\SurveryService.java
     文件        1604  2014-04-28 03:17  hello\src\cn\jhc\service\SurveryServlet.java
     文件        1135  2014-04-28 03:17  hello\src\cn\jhc\service\TotalServlet.java
     文件         610  2014-04-28 03:17  hello\src\cn\jhc\service\UDPSe.java
     文件        1059  2014-04-28 03:17  hello\src\cn\jhc\service\test.java
     文件       32218  2014-04-28 03:17  hello\WebContent\WEB-INF\lib\javax.servlet.jsp.jstl-api.jar
     文件      403279  2014-04-28 03:17  hello\WebContent\WEB-INF\lib\javax.servlet.jsp.jstl.jar
     文件      789885  2014-04-28 03:17  hello\WebContent\WEB-INF\lib\mysql-connector-java-5.1.18-bin.jar
     文件          39  2014-04-28 03:17  hello\WebContent\meta-INF\MANIFEST.MF
     文件         249  2014-04-28 03:17  hello\WebContent\WEB-INF\sd.html
     文件      282944  2014-04-28 03:17  hello\WebContent\js\jquery-1.11.0.js
     文件        2863  2014-06-11 01:21  hello\build\classes\reg.class
     文件        1691  2014-06-11 01:21  hello\build\classes\HelloServlet.class
     文件         491  2014-04-28 03:17  hello\.settings\.jsdtscope
     文件         387  2014-04-28 03:17  hello\.settings\org.eclipse.jdt.core.prefs
     文件         533  2014-04-28 03:17  hello\.settings\org.eclipse.wst.common.component
     文件         335  2014-04-28 03:17  hello\.settings\org.eclipse.wst.common.project.facet.core.xml
............此处省略36个文件信息