package MysqlTest;

import java.io.FileInputStream;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.Statement;
import java.util.Properties;

public class ExecuteDDL {
private String driver;
private String url;
private String user;
private String pass;
public void initParam(String paramFile) throws Exception
{
Properties props=new Properties();
//使用Properties类来加载属性文件
props.load(new FileInputStream(paramFile));
driver=props.getProperty("driver");
url=props.getProperty("url");
user=props.getProperty("user");
pass=props.getProperty("pass");
}
public void createTable(String sql) throws Exception
{
Class.forName(driver);//加载驱动
try(
Connection conn=DriverManager.getConnection(url,user,pass);//获取数据库连接,使用Connection来创建一个Statment对象
Statement stmt=conn.createStatement())
{
stmt.executeUpdate(sql); //执行DDL,创建数据表
}
}
public static void main (String[] args) throws Exception
{
ExecuteDDL ed=new ExecuteDDL();
ed.initParam("src/MysqlTest/my.ini");
ed.createTable("create table jdbc_test"+"(jdbc_id int auto_increment primary key,"+"jdbc_name varchar(255),"+"jdbc_desc text);");
System.out.println("----建表成功----");
}
}

错误描述：

Exception in thread "main" java.lang.NullPointerException
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Unknown Source)
at MysqlTest.ExecuteDDL.createTable(ExecuteDDL.java:26)
at MysqlTest.ExecuteDDL.main(ExecuteDDL.java:38)