Orders

import java.io.*; import java.sql.*; import javax.naming.*; import javax.servlet.*; import javax.servlet.http.*; import javax.sql.*; public class OrdersServlet extends HttpServlet { private static long pooledDuration, nonPooledDuration; private static long pooledCount, nonPooledCount; private DataSource datasource = null; public void init(ServletConfig config) throws ServletException { try { //Create a datasource for pooled connections. //Register the driver for non pooled connections. Context initCtx = new InitialContext(); Context envCtx = (Context) initCtx.lookup("java:comp/env"); datasource = (DataSource) envCtx.lookup("jdbc/MyDataSource"); Class.forName("oracle.jdbc.driver.OracleDriver").newInstance(); } catch (Exception e) { throw new ServletException(e.getMessage()); } } private Connection getConnection(boolean pooledConnection) throws SQLException { if (pooledConnection) { pooledCount++; return datasource.getConnection(); } else { nonPooledCount++; Connection con = DriverManager.getConnection("jdbc:oracle:thin:@///orcl", "scott", "tiger"); return con; } } public void doGet (HttpServletRequest req, HttpServletResponse res) throws ServletException, IOException { String queryStr = req.getQueryString(); boolean poolingEnabled = queryStr == null || !queryStr.equals("disablePooling"); PrintWriter out = res.getWriter(); res.setContentType("text/html"); out.println("Orders"); out.println("
PooledConnectionCount:"+pooledCount+", nonPooledConnectionCount:"+nonPooledCount+"
"); if (pooledDuration > 0 && nonPooledDuration > 0) { out.println("
"+ "Average pooled response:"+pooledDuration/pooledCount+ "Average non pooled response:"+nonPooledDuration/nonPooledCount); } Connection connection = null; Statement stmt = null; ResultSet rs = null; long startTime = System.currentTimeMillis(); try { connection = getConnection(poolingEnabled); stmt = connection.createStatement(); String sqlSelect = "SELECT ORDERS.ORDER_ID, ORDERS.CUSTOMER_ID," + "LINES.LINE_ITEM_ID, LINES.LINE_ITEM_ID, LINES.PRODUCT_ID, LINES.UNIT_PRICE, LINES.QUANTITY "+ "FROM OE.ORDERS ORDERS INNER JOIN OE.ORDER_ITEMS LINES "+ "ON LINES.ORDER_ID = ORDERS.ORDER_ID "+ "ORDER BY ORDER_ID, LINES.LINE_ITEM_ID"; rs = stmt.executeQuery(sqlSelect); ResultSetMetaData dbMeta = rs.getMetaData(); out.println("
"); //Create the table headers out.println(""); for (int col=0; col" + dbMeta.getColumnName(col+1) + ""); } out.println(""); //Create the table data while (rs.next()) { out.println(""); for (int col=0; col < dbMeta.getColumnCount(); col++) { out.println(""); } out.println(""); } out.println("

" + rs.getString(col+1) + "

"); out.println(""); connection.close(); } catch (SQLException e) { throw new ServletException(e.getMessage()); } finally { try {if (rs != null) rs.close();} catch (SQLException e) {} try {if (stmt != null) stmt.close();} catch (SQLException e) {} try {if (connection != null) connection.close();} catch (SQLException e) {} long elapsed = System.currentTimeMillis() - startTime; //Collect the times if (poolingEnabled) this.pooledDuration += elapsed; else this.nonPooledDuration += elapsed; } } }