分类
提供详细的代码-如何在Servlet中连接数据库‖
| import java.sql.*; |
| import java.io.*; |
| import javax.servlet.*; |
| import javax.servlet.http.*; |
| public class Databas | e extends HttpServlet |
| { |
| public void doGet ( |
| HttpServletRequest request, |
| HttpServletResponse response |
| ) throws ServletException, IOException |
| { |
| PrintWriter out; |
| String | title = "Simple Servlet c | onnecting to Oracle DB"; |
| // set content t | ype and other response heade | r fields first |
| response.setContentType("text/ht | ml;charset=GB2312"); |
| // then write the data of th | e response |
| out = response.getWriter(); |
| out.println("<HTML><HEAD><TITLE>"); |
| out.println(title); |
| out.println("</TITLE></HEAD><BODY>"); |
| out.println("<H1>" + title + "</H1>"); |
| out.println("<P>This is output from SimpleServlet."); |
| String driverName = | "oracle.jdbc.driver.OracleDr | iver"; |
| Driver d; |
| Connection con; |
| Statement stmt; |
| ResultSet results; |
| try { |
| d = (Driver)Class.forNam | e(driverName).newInstance(); |
| con = Driver ndb@111.222.1.36:1521:PC | Manager.getConnection("jdbc: 36"); | oracle:thin:ndb/ |
| stmt = con.createStatement(); |
| String sqlstr = "sel | ect SYSDATE from dual"; |
| results = stmt.executeQuery(sqlstr); |
| displayResult(results,out); |
| stmt.close(); |
| con.close(); |
| } |
| catch (Exception e) { |
| out.println( | "error: " + e.toString()); | |
| } |
| out.println("</BODY></HTML>"); |
| out.close(); |
| } |
| public void displayResult(Result | Set results,PrintWriter out){ |
| StringBuffer buf = new Strin | gBuffer(); |
| String temp; |
| try { |
| ResultSetMet | aData rsmd = results.getMeta | Data(); |
| int numCols | = rsmd.getColumnCount(); |
| int i, rowcount = 0; |
| // get column header info |
| for (i=1; i <= numCols; i++){ |
| if (i > 1) buf.append(","); |
| buf.append(rsmd.getC | olumnLabel(i)); |
| } |
| buf.append(" |
| "); |
| while (resul | ts.next() && rowcount < 1 | 00){ |
| for (i=1 | ; i <= numCols; i++) { |
| if (i > 1) buf.append(","); |
| buf.append((resu | lts.getString(i))); |
| } |
| buf.append("<br>"); |
| rowcount++; |
| } |
| out.println("<br>"); |
| out.println(buf.toString()); |
| results.close(); |
| } catch (Exception e) { |
| out.println( | "error: " + e.toString()); | |
| return; |
| } |
| } |
| } |