下面的 servlet 连接到数据库，检索大量信息，然后以表格格式打印所有信息。
如果我创建了 JSP 文件，是否有更有效的方法来执行此操作？而不是在 Java servlet 中输出所有这些 HTML 代码？
import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;
import java.sql.*;
public class PersonalInfoOutput extends HttpServlet {
protected void processRequest(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
response.setContentType("text/html;charset=UTF-8");
PrintWriter out = response.getWriter();
HttpSession session = request.getSession(false);
String employeeid = "";
if(session != null) {
employeeid = (String)session.getAttribute("employeeid");
}
boolean st = false;
try {
Class.forName("com.mysql.jdbc.Driver").newInstance();
Connection con = DriverManager.getConnection("jdbc:mysql://localhost:3306/payroll_system", "root", "");
PreparedStatement ps = con.prepareStatement("select employeeID, FirstName, LastName, Admin, DOB, Address, Email, HourlyRate, Gender, ALeaveBalance, SLeaveBalance, ActiveStatus, Role, BSB, BankName, AccNumber, SuperNumber, SuperCompany from payroll_system.employee_info where employeeID = ?");
ps.setString(1, employeeid);
ResultSet rs = ps.executeQuery();
st = rs.next();
if(st){
boolean adminTrue = rs.getBoolean("Admin");
boolean activeTrue = rs.getBoolean("ActiveStatus");
out.println("<html>");
out.println("<head>");
out.println("<style>");
out.println("table { border-collapse: collapse; width: 50%; } th, td { text-align: left; padding: 8px; } tr:nth-child(even){background-color: #f2f2f2}");
out.println("tr:hover {background-color: #e2f4ff;}");
out.println("</style>");
out.println("<link rel = stylesheet type = text/css href = main.css>");
out.println("<link rel = stylesheet type = text/css href = sidebar.css>");
out.println("<title>Personal Information</title>");
out.print("</head>");
out.println("<body>");
if(adminTrue){
out.println("<ul>");
out.println("<li><a class=active >View Personal Information</a></li>");
out.println("<li><a href=index.html>View Expense Claims</a></li>");
out.println("<li><a href=index.html>View Payslips</a></li>");
out.println("<li><a href=changePassAdmin.html>Change Password</a></li>");
out.println("<li><a href=manageEmployee.html>Maintain Employee Information</a></li>");
out.println("<li><a href=index.html>Maintain Tax Information</a></li>");
out.println("<li><a href=index.html>Maintain Payroll Items</a></li>");
out.println("<li><a href=index.html>Maintain Timesheet</a></li>");
out.println("<li><a href=index.html>Maintain Employee Expenses</a></li>");
out.println("<li><a href=index.html>Run Payroll</a></li>");
out.println("<li><a href=index.html>Generate Reports</a></li>");
out.println("</ul>");
out.println("<div style=margin-left:25%;padding:1px 16px;height:1000px;>");
out.println("</div>");
}
else if(!adminTrue){
out.println("<ul>");
out.println("<li><a class=active href=PersonalInfoOutput>View Personal Information</a></li>");
out.println("<li><a href=xyz>View Expense Claims</a></li>");
out.println("<li><a href=xyz>View Payslips</a></li>");
out.println("<li><a href=.html>Change Password</a></li>");
out.println("</ul>");
out.println("<div style=margin-left:25%;padding:1px 16px;height:1000px;>");
out.println("</div>");
}
out.println("<div id=container>");
out.println("<h1>Personal Information</h1>");
out.println("<table border =1>");
out.println("<tr>");
out.println("<td>Name</td>");
out.println("<td>"+ rs.getString("FirstName") + " " + rs.getString("LastName") + "</td>");
out.println("</tr>");
out.println("<tr>");
out.println("<td>Employee ID</td>");
out.println("<td>"+ rs.getString("employeeID")+"</td>");
out.println("</tr>");
if(adminTrue) {
out.println("<tr>");
out.println("<td>Admin</td>");
out.println("<td>Yes</td>");
out.println("</tr>");
}
else{
out.println("<tr>");
out.println("<td>Admin</td>");
out.println("<td>No</td>");
out.println("</tr>");
}
out.println("<tr>");
out.println("<td>Date Of Birth</td>");
out.println("<td>"+ rs.getString("DOB")+"</td>");
out.println("</tr>");
out.println("<tr>");
out.println("<td>Residential Address</td>");
out.println("<td>"+ rs.getString("Address")+"</td>");
out.println("</tr>");
out.println("<tr>");
out.println("<td>Email</td>");
out.println("<td>"+ rs.getString("Email")+"</td>");
out.println("</tr>");
out.println("<tr>");
out.println("<td>Hourly Income</td>");
out.println("<td>"+ "$" + rs.getString("HourlyRate")+"</td>");
out.println("</tr>");
out.println("<tr>");
out.println("<td>Gender</td>");
out.println("<td>"+ rs.getString("Gender")+"</td>");
out.println("</tr>");
out.println("<tr>");
out.println("<td>Annual Leave Balance</td>");
out.println("<td>"+ rs.getString("ALeaveBalance")+"</td>");
out.println("</tr>");
out.println("<tr>");
out.println("<td>Sick Leave Balance</td>");
out.println("<td>"+ rs.getString("SLeaveBalance")+"</td>");
out.println("</tr>");
if(activeTrue) {
out.println("<tr>");
out.println("<td>Currently Active</td>");
out.println("<td>Yes</td>");
out.println("</tr>");
}
else {
out.println("<tr>");
out.println("<td>Currently Active</td>");
out.println("<td>No</td>");
out.println("</tr>");
}
out.println("<tr>");
out.println("<td>Role</td>");
out.println("<td>"+ rs.getString("Role")+"</td>");
out.println("</tr>");
out.println("<tr>");
out.println("<td>BSB</td>");
out.println("<td>"+ rs.getString("BSB")+"</td>");
out.println("</tr>");
out.println("<tr>");
out.println("<td>Bank Name</td>");
out.println("<td>"+ rs.getString("BankName")+"</td>");
out.println("</tr>");
out.println("<tr>");
out.println("<td>Bank Account Number</td>");
out.println("<td>"+ rs.getString("AccNumber")+"</td>");
out.println("</tr>");
out.println("<tr>");
out.println("<td>Superannuation Company</td>");
out.println("<td>"+ rs.getString("SuperCompany")+"</td>");
out.println("</tr>");
out.println("<tr>");
out.println("<td>Superannuation Number</td>");
out.println("<td>"+ rs.getString("SuperNumber")+"</td>");
out.println("</tr>");
out.println("</table>");
out.println("</div>");
out.println("</body>");
out.println("</html>");
}
}catch(Exception e)
{
e.printStackTrace();
}
out.close();
}
@Override
protected void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
processRequest(request, response);
}
@Override
protected void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
processRequest(request, response);
}
}
如果您从Java代码中提取所有HTML代码并将其放置到JSP中，那么您可以使用JSP标签和表达式语言对此代码进行额外的处理。您只需将请求转发到 JSP 页面，jsp servlet 将完成剩下的工作。
request.getRequestDispatcher("page.jsp").forward(request, response);