testservlet.java

J2EE指南

import java.io.*; 
import java.sql.*; 
import javax.servlet.*; 
import javax.servlet.http.*; 

public class TestServlet extends HttpServlet {
	private DBConnectionManager connMgr;
public void init(ServletConfig conf) throws ServletException { 
super.init(conf); 
connMgr = DBConnectionManager.getInstance(); 
} 
public void service(HttpServletRequest req, HttpServletResponse res) throws IOException { 
res.setContentType("text/html"); 
PrintWriter out = res.getWriter(); 
Connection con = connMgr.getConnection("idb"); 
if(con==null) 
{ 
out.println("Cant get connection"); 
return; 
} 
ResultSet rs = null; 
ResultSetMetaData md = null; 
Statement stmt = null; 
try { 
stmt = con.createStatement(); 
rs = stmt.executeQuery("SELECT * FROM publishers"); 
md = rs.getMetaData(); 
out.println("Customer data "); 
out.println("<Table>");
while (rs.next()) { 
out.println("<tr>"); 
for (int i =1; i<md.getColumnCount(); i++) { 
out.print("<td>"+rs.getString(i) + "</td>"); 
} 
out.print("</tr>");
} 
out.println("</table>");
stmt.close(); 
//rs.close(); 
} 
catch (SQLException e) { 
e.printStackTrace(out); 
} 
connMgr.freeConnection("idb", con); 
}
public void destroy() { 
connMgr.release(); 
super.destroy(); 
} 
}