Java JDBC技术抽象出来的公共类，个人觉得已经很完美了

package com.bdqn.jdbc.day1.util;

import java.io.InputStream;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.Statement;
import java.util.Properties;

public class JdbcUtil {

private static Properties info = new Properties();

static {
try {
InputStream is = JdbcUtil.class.getResourceAsStream("/com/bdqn/jdbc/day1/util/config.properties");
info.load(is);
is.close();
} catch (Exception e) {// 静态代码块中如果try-catch 想抛出异常 只有一种
throw new ExceptionInInitializerError(e);
}
}

private static final ThreadLocal<Connection> tl = new ThreadLocal<Connection>();

public static Connection getConnection() throws Exception {
Connection conn = tl.get();
if (conn == null) {
Class.forName(info.getProperty("driver"));
conn = DriverManager.getConnection(info.getProperty("url"),
info.getProperty("username"), info.getProperty("password"));
tl.set(conn);
}
return conn ;
}
public static void release(ResultSet rs, Statement stm ,  Connection conn ){
if(rs!=null) try {rs.close();}catch(Exception ex){}
if(stm!=null) try {stm.close();}catch(Exception ex){}
if(conn!=null) try {conn.close();}catch(Exception ex){}
}

public static void main(String[] args) throws Exception {
System.out.println(getConnection());
}
}