设计模式课程 设计模式精讲 15-2 桥接模式源码解析

//
// Source code recreated from a .class file by IntelliJ IDEA
// (powered by Fernflower decompiler)
//

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 {
    }
//class.forName 直接调用该静态块 static { try { DriverManager.registerDriver(new Driver()); } catch (SQLException var1) { throw new RuntimeException("Can‘t register driver!"); } }
}

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

public class DriverManager {
    // List of registered JDBC drivers
    private final static CopyOnWriteArrayList<DriverInfo> registeredDrivers = new CopyOnWriteArrayList<DriverInfo>();
    private static volatile int loginTimeout = 0;
    private static volatile java.io.PrintWriter logWriter = null;
    private static volatile java.io.PrintStream logStream = null;
    // Used in println() to synchronize logWriter
    private final static  Object logSync = new Object();

    /* Prevent the DriverManager class from being instantiated. */
    private DriverManager(){}

 /**
    *内部类，对driver进行封装 */
class DriverInfo {

    final Driver driver; DriverInfo(Driver driver) { this.driver = driver; } public boolean equals(Object other) {
        return (other instanceof DriverInfo)
                && this.driver == ((DriverInfo) other).driver;
    }

    public int hashCode() { return driver.hashCode(); } public String toString() {
        return ("driver[className="  + driver + "]");
    }
}

//注册驱动的方法

public static synchronized void registerDriver(java.sql.Driver driver)
throws SQLException {

/* Register the driver if it has not already been added to our list */
 if(driver != null) {
registeredDrivers.addIfAbsent(new DriverInfo(driver));
 } else {
// This is for compatibility with the original DriverManager
 throw new NullPointerException();
 }

println("registerDriver: " + driver);
}

//获取数据库连接

@CallerSensitive
public static Connection getConnection(String url,
 String user,String password) throws SQLException {
 java.util.Properties info = new java.util.Properties();

 if (user != null) {
 info.put("user",user);
 }
if (password != null) {
 info.put("password",password);
 }

return (getConnection(url,info,Reflection.getCallerClass()));
}
}