1 package com.curriculumDesign.database;  2  3 import java.sql.Connection;  4 import java.sql.DriverManager;  5 import java.util.ArrayList;  6  7 public class ConnectionPool {
    8  9     private static int maxConnectNum = 10; 10 11     private java.sql.Connection conn[] = new Connection[maxConnectNum]; 12 13     private static ArrayList connectPool = new ArrayList(); 14 15     private static int flag = 0; 16 17     public ConnectionPool() {
   18         if (flag == 0) {
   19             init(); 20         } 21     } 22 23     private Connection getConnectionFromDatabase() {
   24         Connection trueConn = null; 25         try {
   26             Class.forName("com.mysql.jdbc.Driver").newInstance(); 27             String url = "jdbc:mysql://localhost:3306/book_store?user=root&password="; 28             trueConn = DriverManager.getConnection(url); 29         } catch (Exception ex) {
   30             System.out.println("数据连接出错了:" + ex.toString()); 31         } 32         return trueConn; 33     } 34 35     //这里建立所有的连接; 36     private void init() {
   37         for (int i = 0; i < maxConnectNum; i++) {
   38             conn[i] = getConnectionFromDatabase(); 39             connectPool.add(i, conn[i]); 40         } 41         flag = 1; 42     } 43 44     //从连接池中取得一个可用的连接 45     public Connection getConnection() {
   46         Connection conn = null; 47         if (connectPool.size() == 0) {
   48             try {
   49                 java.lang.Thread.sleep(1000); 50                 getConnection(); 51             } catch (InterruptedException ex) {
   52                 System.out.println("连接全部用光,这里sleep出错了."); 53             } 54         } else {
   55             conn = (Connection) connectPool.remove(0); 56         } 57 58         return conn; 59     } 60 61     //提供给外部程序调用,不用的连接放回连接池当中... 62     public boolean release(Connection conn) {
   63         return connectPool.add(conn); 64     } 65 }

摘抄别人的，并非原创