javaee区数据库开发基础.ppt

连接池类 ConnectionPool package db; import java.sql.*;* import java.util.Vector; public class ConnectionPool { private VectorConnection pool; private int poolSize = 10; private static ConnectionPool instance = null; public static ConnectionPool getInstance() { if (instance == null) { instance = new ConnectionPool(); } return instance; } 《1》 连接池类 ConnectionPool private ConnectionPool() { pool = new VectorConnection(poolSize); Connection conn = null; for (int i = 0; i poolSize; i++) { try { Class.forName(com.mysql.jdbc.Driver); conn = DriverManager.getConnection(jdbc:odbc:tt); pool.add(conn); } catch (Exception e) { e.printStackTrace(); } } } 《2》 连接池类 ConnectionPool public synchronized Connection getConnection() { if (pool.size() 0) { Connection conn = pool.get(0); pool.remove(conn); return conn; } else { return null; } } public synchronized void release(Connection conn) { pool.add(conn); } } 《3》 使用连接池 body % db.ConnectionPool cp = db.ConnectionPool.getInstance(); long start = System.currentTimeMillis(); int loops = Integer.parseInt(request.getParameter(loops));; for (int i = 0; i loops; i++) { Connection cn = cp.getConnection(); if (cn != null) { cp.release(cn); } } out.print(h1利用连接池连接 + loops + 次，用时 + (System.currentTimeMillis() - start) + ms/h1); % /body useloops.jsp 不使用连接池 %@page import=java.sql.* contentType=text/html pageEncoding=UTF-8% body % long start = System.currentTimeMillis(); int loops = Integer.parseInt(request.getParameter(loops)); Cl