分享一个MySQL ReplicationDriver类代码

public static void main(String[] args) throws Exception {
    ReplicationDriver driver = new ReplicationDriver();
    Properties props = new Properties();
    // We want this for failover on the slaves
    props.put("autoReconnect", "true");
 // We want to load balance between the slaves
    props.put("roundRobinLoadBalance", "true");
    props.put("user", "foo");
    props.put("password", "bar");
    //
    // Looks like a normal MySQL JDBC url, with a
    // comma-separated list of hosts, the first 
    // being the 'master', the rest being any number
    // of slaves that the driver will load balance against
    //
    Connection conn =
        driver.connect("jdbc:mysql://master,slave1,slave2,slave3/test",
            props);
    //
    // Perform read/write work on the master
    // by setting the read-only flag to "false"
    //
  //这个节点应该是通过spring的事务管理来设置，同时这个conn对象应该不是一个真正的connection，
	    //而是一个代理类，通过设置readonly，代理类会去使用不同的connection，
	    //那么问题是它该代理类使用的connection是哪里取的，抑或说难道它每次都会新开一个connection？，需要看源代码
conn.setReadOnly(false);
conn.setAutoCommit(false);
    conn.createStatement().executeUpdate("UPDATE some_table ....");
    conn.commit();
 //
    // Now, do a query from a slave, the driver automatically picks one
    // from the list
    //
conn.setReadOnly(true);
  ResultSet rs = 
      conn.createStatement().executeQuery("SELECT a,b FROM alt_table");
     .......
  }