前两天学习Servlet时，用Servlet做了一个小小个学生查询功能，现在学习了JSP就用JSP来实现这个小功能。
首先新建一个JSP文件student.jsp,代码如下：
1 <%@ page language="java" contentType="text/html;charset=GB2312" %> 2 <%@ page import="java.sql.Timestamp"%> 3 <%@ page import="java.text.*"%> 4 <%@ page import="java.util.*"%> 5 <%@ page import="com.pojo.*"%> 6 <%@ page import="com.services.*"%> 7 <html> 8 <head> 9 <title>学生信息</title> 10 </head> 11 <body> 12 <form action="student.jsp" method="GET"> 13 出生日期：<input type="text" name="begindate">至<input type="text" name="enddate"> 14 <input type="submit" value="查询"> 15 </form> 16 <% 17 String sBeginDate = request.getParameter("begindate"); 18 String sEndDate = request.getParameter("enddate"); 19 //将字符串转换为Timestamp 20 Timestamp beginDate = Timestamp.valueOf("1900-1-1 00:00:00"); 21 Timestamp endDate = Timestamp.valueOf("1900-1-1 00:00:00"); 22 try{ 23 beginDate = Timestamp.valueOf(sBeginDate+" 0:0:0"); 24 endDate = Timestamp.valueOf(sEndDate+" 0:0:0"); 25 }catch(Exception e){ 26 e.printStackTrace(); 27 } 28 StudentService ss = new StudentService(); 29 //从数据库中查询结果 30 List<Student> l = ss.getStudentByDate(beginDate,endDate); 31 %> 32 <% 33 if(l.size()!= 0 && l!=null){ 34 %> 35 <table border="1"> 36 <tr> 37 <td>学号</td> 38 <td>姓名</td> 39 <td>出生日期</td> 40 <td>性别</td> 41 <td>家庭住址</td> 42 </tr> 43 <% 44 for(Iterator<Student> iter=l.iterator();iter.hasNext();){ 45 Student s = iter.next(); 46 %> 47 <tr> 48 <td><%=s.getSId()%></td> 49 <td><%=s.getSName()%></td> 50 <td><%=new SimpleDateFormat("yyyy-MM-dd").format(s.getSDate())%></td> 51 <td><%=s.getSSex()%></td> 52 <td><%=s.getSAddr()%></td> 53 </tr> 54 <%}%> 55 </table> 56 <% 57 } 58 %> 59 </body> 60 </html>
再把相应的业务逻辑jar包和数据库驱动拷贝到lib目录下。
编译后的student_jsp.java代码如下：
1 package org.apache.jsp; 2 3 import javax.servlet.*; 4 import javax.servlet.http.*; 5 import javax.servlet.jsp.*; 6 import java.sql.Timestamp; 7 import java.text.*; 8 import java.util.*; 9 import com.pojo.*; 10 import com.services.*; 11 12 public final class student_jsp extends org.apache.jasper.runtime.HttpJspBase 13 implements org.apache.jasper.runtime.JspSourceDependent { 14 15 private static final JspFactory _jspxFactory = JspFactory.getDefaultFactory(); 16 17 private static java.util.List _jspx_dependants; 18 19 private javax.el.ExpressionFactory _el_expressionfactory; 20 private org.apache.AnnotationProcessor _jsp_annotationprocessor; 21 22 public Object getDependants() { 23 return _jspx_dependants; 24 } 25 26 public void _jspInit() { 27 _el_expressionfactory = _jspxFactory.getJspApplicationContext(getServletConfig().getServletContext()).getExpressionFactory(); 28 _jsp_annotationprocessor = (org.apache.AnnotationProcessor) getServletConfig().getServletContext().getAttribute(org.apache.AnnotationProcessor.class.getName()); 29 } 30 31 public void _jspDestroy() { 32 } 33 34 public void _jspService(HttpServletRequest request, HttpServletResponse response) 35 throws java.io.IOException, ServletException { 36 37 PageContext pageContext = null; 38 HttpSession session = null; 39 ServletContext application = null; 40 ServletConfig config = null; 41 JspWriter out = null; 42 Object page = this; 43 JspWriter _jspx_out = null; 44 PageContext _jspx_page_context = null; 45 46 47 try { 48 response.setContentType("text/html;charset=GB2312"); 49 pageContext = _jspxFactory.getPageContext(this, request, response, 50 null, true, 8192, true); 51 _jspx_page_context = pageContext; 52 application = pageContext.getServletContext(); 53 config = pageContext.getServletConfig(); 54 session = pageContext.getSession(); 55 out = pageContext.getOut(); 56 _jspx_out = out; 57 58 out.write("\r\n"); 59 out.write("\r\n"); 60 out.write("\r\n"); 61 out.write("\r\n"); 62 out.write("\r\n"); 63 out.write("\r\n"); 64 out.write("<html>\r\n"); 65 out.write("\t<head>\r\n"); 66 out.write("\t\t<title>学生信息</title>\r\n"); 67 out.write("\t</head>\r\n"); 68 out.write("\t<body>\r\n"); 69 out.write("\t\t<form action=\"student.jsp\" method=\"GET\">\r\n"); 70 out.write("\t\t\t出生日期：<input type=\"text\" name=\"begindate\">至<input type=\"text\" name=\"enddate\">\r\n"); 71 out.write("\t\t\t<input type=\"submit\" value=\"查询\">\r\n"); 72 out.write("\t\t</form>\r\n"); 73 out.write("\t\t"); 74 75 String sBeginDate = request.getParameter("begindate"); 76 String sEndDate = request.getParameter("enddate"); 77 //将字符串转换为Timestamp 78 Timestamp beginDate = Timestamp.valueOf("1900-1-1 00:00:00"); 79 Timestamp endDate = Timestamp.valueOf("1900-1-1 00:00:00"); 80 try{ 81 beginDate = Timestamp.valueOf(sBeginDate+" 0:0:0"); 82 endDate = Timestamp.valueOf(sEndDate+" 0:0:0"); 83 }catch(Exception e){ 84 e.printStackTrace(); 85 } 86 StudentService ss = new StudentService(); 87 //从数据库中查询结果 88 List<Student> l = ss.getStudentByDate(beginDate,endDate); 89 90 out.write("\r\n"); 91 out.write("\t\t"); 92 93 if(l.size()!= 0 && l!=null){ 94 95 out.write("\r\n"); 96 out.write("\t\t<table border=\"1\">\r\n"); 97 out.write("\t\t\t<tr>\r\n"); 98 out.write("\t\t\t\t<td>学号</td>\r\n"); 99 out.write("\t\t\t\t<td>姓名</td>\r\n"); 100 out.write("\t\t\t\t<td>出生日期</td>\r\n"); 101 out.write("\t\t\t\t<td>性别</td>\r\n"); 102 out.write("\t\t\t\t<td>家庭住址</td>\r\n"); 103 out.write("\t\t\t</tr>\r\n"); 104 out.write("\t\t\t"); 105 106 for(Iterator<Student> iter=l.iterator();iter.hasNext();){ 107 Student s = iter.next(); 108 109 out.write("\r\n"); 110 out.write("\t\t\t<tr>\r\n"); 111 out.write("\t\t\t\t<td>"); 112 out.print(s.getSId()); 113 out.write("</td>\r\n"); 114 out.write("\t\t\t\t<td>"); 115 out.print(s.getSName()); 116 out.write("</td>\r\n"); 117 out.write("\t\t\t\t<td>"); 118 out.print(new SimpleDateFormat("yyyy-MM-dd").format(s.getSDate())); 119 out.write("</td>\r\n"); 120 out.write("\t\t\t\t<td>"); 121 out.print(s.getSSex()); 122 out.write("</td>\r\n"); 123 out.write("\t\t\t\t<td>"); 124 out.print(s.getSAddr()); 125 out.write("</td>\r\n"); 126 out.write("\t\t\t</tr>\r\n"); 127 out.write("\t\t\t"); 128 } 129 out.write("\r\n"); 130 out.write("\t\t</table>\r\n"); 131 out.write("\t\t"); 132 133 } 134 135 out.write("\r\n"); 136 out.write("\t</body>\r\n"); 137 out.write("</html>"); 138 } catch (Throwable t) { 139 if (!(t instanceof SkipPageException)){ 140 out = _jspx_out; 141 if (out != null && out.getBufferSize() != 0) 142 try { out.clearBuffer(); } catch (java.io.IOException e) {} 143 if (_jspx_page_context != null) _jspx_page_context.handlePageException(t); 144 } 145 } finally { 146 _jspxFactory.releasePageContext(_jspx_page_context); 147 } 148 } 149 }
相比Servlet,JSP的实现简单了许多，在JSP文件中HTML语句可以直接写，不需要拼凑。