线程安全的jdbc连接池

import java.io.File; import java.io.FileInputStream; import java.io.InputStream; import java.io.PrintWriter; import java.lang.reflect.InvocationHandler; import java.lang.reflect.Method; import java.lang.reflect.Proxy; import java.sql.Connection; import java.sql.DriverManager; import java.sql.SQLException; import java.util.Properties; import java.util.concurrent.ConcurrentLinkedQueue; import javax.sql.DataSource; import org.apache.commons.lang3.StringUtils; import org.apache.commons.logging.Log; public class JdbcPool implements DataSource{ private static final Log log = LogUtils.getLog(JdbcPool.class); /** * @Field: listConnections * 使用LinkedList集合来存放数据库链接， * 由于要频繁读写List集合，所以这里使用LinkedList存储数据库连接比较合适 */ // private static LinkedList<Connection> listConnections = new LinkedList<Connection>(); private static ConcurrentLinkedQueue<Connection> listConnections = new ConcurrentLinkedQueue<Connection>(); private final static String filepath = Path.getCurrentPath() + "/config/db.properties"; static{ //在静态代码块中加载db.properties数据库配置文件 File file = new File(filepath); Properties prop = new Properties(); try { InputStream in= new FileInputStream(file); prop.load(in); String driver = prop.getProperty("driver"); String url = prop.getProperty("url"); String username = prop.getProperty("username"); String password = prop.getProperty("password"); //数据库连接池的初始化连接数大小 int jdbcPoolInitSize =Integer.parseInt(prop.getProperty("jdbcPoolInitSize")); //加载数据库驱动 Class.forName(driver); for (int i = 0; i < jdbcPoolInitSize; i++) { Connection conn = DriverManager.getConnection(url, username, password); //将获取到的数据库连接加入到listConnections集合中，listConnections集合此时就是一个存放了数据库连接的连接池 listConnections.add(conn); } } catch (Exception e) { e.printStackTrace(); log.error(e); } } public PrintWriter getLogWriter() throws SQLException { // TODO Auto-generated method stub return null; } public void setLogWriter(PrintWriter out) throws SQLException { // TODO Auto-generated method stub } public void setLoginTimeout(int seconds) throws SQLException { // TODO Auto-generated method stub } public int getLoginTimeout() throws SQLException { // TODO Auto-generated method stub return 0; } public <T> T unwrap(Class<T> iface) throws SQLException { // TODO Auto-generated method stub return null; } public boolean isWrapperFor(Class<?> iface) throws SQLException { // TODO Auto-generated method stub return false; } /* 获取数据库连接 * @see javax.sql.DataSource#getConnection() */ public Connection getConnection() throws SQLException { // 如果数据库连接池中的连接对象的个数大于0 if (listConnections.size() > 0) { // if (!listConnections.isEmpty()) { // 从listConnections集合中获取一个数据库连接 final Connection conn = listConnections.poll(); // 返回Connection对象的代理对象 return (Connection) Proxy.newProxyInstance(JdbcPool.class.getClassLoader(), new Class[] { Connection.class }, new InvocationHandler() { public Object invoke(Object proxy, Method method, Object[] args) throws Throwable { if (!method.getName().equals("close")) { return method.invoke(conn, args); } else { // 如果调用的是Connection对象的close方法，就把conn还给数据库连接池 listConnections.add(conn); return null; } } }); } else { return null; } } public Connection getConnection(String username, String password) throws SQLException { return null; } /** * 获取多线程的线程池大小 * @return */ public static int getExecutorPoolSize(){ return executorPoolSize; } /** * 获取多线程中每个任务中每次查询的数据条数 * @return */ public static int getQuerySizeOneTime(){ return querySizeOneTime; } /** * 获取redis数据存储的有效时间 * @return */ public static int getExpireTime(){ return expiretime; } }