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 db2private 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());}}}}