JDBC_demo:java连接mysql过程

1.任何数据库驱动程序都提供对java.sql.Driver接口的驱动类，mysql-connector-java-5.1.39-bin.jar中Driver：

package com.mysql.jdbc;

import java.sql.DriverManager;
import java.sql.SQLException;

public class Driver extends NonRegisteringDriver
  implements java.sql.Driver
{
  public Driver()
    throws SQLException
  {
  }

  static
  {
    try
    {
      DriverManager.registerDriver(new Driver());
    } catch (SQLException E) {
      throw new RuntimeException("Can't register driver!");
    }
  }
}

实际上Class.forName("com.mysql.jdbc.Driver")--->DriverManager.registerDriver(new Driver())。java.sql.DriverManager类是JDBC的管理层，负责管理JDBC驱动程序的基本服务。在DriverManager中Driver被包装为DriverInfo类，存储在：

　　 private final static CopyOnWriteArrayList<DriverInfo> registeredDrivers = new CopyOnWriteArrayList<>();

2.Connection con= DriverManager.getConnection(url,"user","pass");遍历存储在registeredDrivers中的DriverInfo，调用各自的connect()。

     for(DriverInfo aDriver : registeredDrivers) {
            // If the caller does not have permission to load the driver then
            // skip it.
            if(isDriverAllowed(aDriver.driver, callerCL)) {
                try {
                    println("    trying " + aDriver.driver.getClass().getName());
                    Connection con = aDriver.driver.connect(url, info);
                    if (con != null) {
                        // Success!
                        println("getConnection returning " + aDriver.driver.getClass().getName());
                        return (con);
                    }
                } catch (SQLException ex) {
                    if (reason == null) {
                        reason = ex;
                    }
                }

            } else {
                println("    skipping: " + aDriver.getClass().getName());
            }

        }

3.com.mysql.jdbc.Driver继承NonRegisteringDriver，实际的connect在com.mysql.jdbc.NonRegisteringDriver.connect()中实现,方法返回类型为java.sql.Connection。

public java.sql.Connection connect(String url, Properties info)
    throws SQLException
  {
    if (url == null) {
      throw SQLError.createSQLException(Messages.getString("NonRegisteringDriver.1"), "08001", null);
    }

    if (StringUtils.startsWithIgnoreCase(url, "jdbc:mysql:loadbalance://"))
      return connectLoadBalanced(url, info);
    if (StringUtils.startsWithIgnoreCase(url, "jdbc:mysql:replication://")) {
      return connectReplicationConnection(url, info);
    }

    Properties props = null;

    if ((props = parseURL(url, info)) == null) {
      return null;
    }

    if (!"1".equals(props.getProperty("NUM_HOSTS"))) {
      return connectFailover(url, info);
    }
    try
    {
      return ConnectionImpl.getInstance(host(props), port(props), props, database(props), url);
    }
    catch (SQLException sqlEx)
    {
      throw sqlEx;
    } catch (Exception ex) {
      SQLException sqlEx = SQLError.createSQLException(Messages.getString("NonRegisteringDriver.17") + ex.toString() + Messages.getString("NonRegisteringDriver.18"), "08001", null);

      sqlEx.initCause(ex);

      throw sqlEx;
    }
  }

4.那么mysql-connector-java-5.1.39-bin.jar中具体是怎么执行sql的，怎么学习，有哪些书可以看呢？？？