首页 > 代码库 > ThreadLocal,LinkedBlockingQueue,线程池 获取数据库连接2改进
ThreadLocal,LinkedBlockingQueue,线程池 获取数据库连接2改进
package com.ctl.util; import java.sql.Connection; import java.sql.DriverManager; import java.sql.SQLException; import java.util.Random; import java.util.concurrent.LinkedBlockingQueue; import java.util.concurrent.TimeUnit; import com.ctl.util.ConfigUtils; import com.ctl.util.LogUtil; public class ThreadLocalBlockingQueueUtils { private static ThreadLocal<LinkedBlockingQueue<Connection>> queueHoder = new ThreadLocal<LinkedBlockingQueue<Connection>>(); public static int num = 0; private static String driver; private static String url; private static String username; private static String password; private static int threadPoolMaxNum; private static int threadPoolMinNum; private static LogUtil log; // \u6570\u636E\u5E93\u7C7B\u578Boracle mysql db2 private static String databasetype; public static int getThreadPoolMaxNum() { return threadPoolMaxNum; } public static int getThreadPoolMinNum() { return threadPoolMinNum; } public static String getUrl() { return url; } public static String getUsername() { return username; } public static String getPassword() { return password; } static { log = new LogUtil(); databasetype = ConfigUtils.getType("databasetype"); threadPoolMaxNum = Integer.parseInt(ConfigUtils .getType("threadPoolMaxNum")); threadPoolMinNum = Integer.parseInt(ConfigUtils .getType("threadPoolMinNum")); if (databasetype.equals("mysql")) { driver = ConfigUtils.getType("mysql.driver"); url = ConfigUtils.getType("mysql.url"); username = ConfigUtils.getType("mysql.username"); password = ConfigUtils.getType("mysql.password"); } else if (databasetype.equals("oracle")) { driver = ConfigUtils.getType("oracle.driver"); url = ConfigUtils.getType("oracle.url"); username = ConfigUtils.getType("oracle.username"); password = ConfigUtils.getType("oracle.password"); } try { Class.forName(driver); } catch (ClassNotFoundException e) { System.out.println(e.getMessage()); } CreateConnection createConn = new CreateConnection(); createConn.setDaemon(true); createConn.start(); } public static synchronized LinkedBlockingQueue<Connection> getQueue() { LinkedBlockingQueue<Connection> queue = queueHoder.get(); if (queue == null) { queue = new LinkedBlockingQueue<Connection>(threadPoolMaxNum); queueHoder.set(queue); return queue; } return queue; } // static void start() { // Tom tom = new Tom(); // tom.start(); // for(;;){ // try { // Thread.sleep(200); // System.out.println("/*************"+getConnection()+"*************/"); // } catch (InterruptedException e) { // } // } // } // // public static void main(String[] args) { // ThreadLocalBlockingQueueUtils.start(); // } public static Connection getConnection() { // System.out.println("进入getConnection"); class GetConnectionClazz extends Thread { LinkedBlockingQueue<Connection> queue = ThreadLocalBlockingQueueUtils .getQueue(); private Connection conn; private int queueSize; public int getQueueSize() { return queueSize; } public Connection getConn() { return conn; } public synchronized void run() { // System.out.println("进入getConnection run()"); try { // System.err.println("-----"+conn+"--------"); while (conn == null) {// 很重要没有该while循环当按F5不断刷新时,只要有一个取出来为空后面的全为空 conn = queue.poll(2, TimeUnit.SECONDS); } queueSize=queue.size(); // System.err.println("*******"+conn+"*********"); // if (conn != null) { // System.err.println("\u3010" + queue.size() + "\u3011" // + "getConnecion\u6210\u529F\uFF1A" + conn); // } } catch (InterruptedException e) { log.WriteLine("getConnection", e.getMessage()); } } } GetConnectionClazz jj = new GetConnectionClazz(); jj.start(); try { jj.join(); } catch (InterruptedException e) { log.WriteLine("getConnection()", e.getMessage()); } log.WriteLine("getConnection()","\u3010" + jj.getQueueSize() + "\u3011"+ "getConnecion\u6210\u529F\uFF1A" + jj.getConn()); return jj.getConn(); } } // class GG extends Thread { // public void run() { // for (;;){ // try { // ThreadLocalBlockingQueueUtils.getConnection(); // Thread.sleep(300); // } catch (Exception e) { // } // } // } // } /** * @descritpion 创建数据库连接的线程类 * @author Administrator * */ class CreateConnection extends Thread { LinkedBlockingQueue<Connection> queue = ThreadLocalBlockingQueueUtils .getQueue(); LogUtil log = new LogUtil(); public synchronized void run() { boolean result = false; while (true) { try { Random rand=new Random(); int num=ThreadLocalBlockingQueueUtils.getThreadPoolMaxNum()-ThreadLocalBlockingQueueUtils.getThreadPoolMinNum(); int randSize=rand.nextInt(num)+1; if(queue.size()>=randSize){ Thread.sleep(100); continue; } Connection conn = null; conn = DriverManager.getConnection( ThreadLocalBlockingQueueUtils.getUrl(), ThreadLocalBlockingQueueUtils.getUsername(), ThreadLocalBlockingQueueUtils.getPassword()); if (conn != null) { result = queue.offer(conn, 1, TimeUnit.SECONDS); } else { // System.out.println("DriverManager.getConnection is null"); log.WriteLine("CreateConnection.run()", "DriverManager.getConnection()返回 null"); continue; } if (result == false) { Thread.sleep(100); log.WriteLine("CreateConnection.run()", "已达到最大连接数queue.size()=" + queue.size()); // System.out.println("已经满了size=【" + queue.size() + "】"); } else { log.WriteLine("CreateConnection.run()", "\u3010" + queue.size() + "\u3011" + "createConnection success:" + conn); // System.out.println("\u3010" + queue.size() + "\u3011" // + "createConnection success:" + conn); } } catch (InterruptedException e) { // e.printStackTrace(); log.WriteLine("getConnection", e.getMessage()); // System.err.println(e.getMessage()); } catch (SQLException e) { log.WriteLine("getConnection", e.getMessage()); // e.printStackTrace(); // System.err.println(e.getMessage()); } } } }
声明:以上内容来自用户投稿及互联网公开渠道收集整理发布,本网站不拥有所有权,未作人工编辑处理,也不承担相关法律责任,若内容有误或涉及侵权可进行投诉: 投诉/举报 工作人员会在5个工作日内联系你,一经查实,本站将立刻删除涉嫌侵权内容。