Connect to MYSQL using JDBC

It took me a morning to debug a program and finally succeeded. Although it was a few simple words, I had some gains in the process ~ I have a lot of feelings.

The question is to use JDBC to connect to MYSQL. It would have been okay to use ejbs directly without any connection. But I think if I just want to make a simple model, would I also use ejbs? So you need to know how to connect to the database.

I first downloaded the MYSQL driver from mysql. COM '~ Set include in CLASSPATH

The program is as follows ~~

Package com. myapp. struts;

Import com. mysql. jdbc. Driver;

Import java. SQL .*;

Import javax. servlet .*;

Import javax. servlet. http .*;

Import java. io .*;

/**

*

* @ Author zj395455

*/

Public class NewClass {

Public NewClass (){

}

Public static void main (String [] args ){

Try {

Class. forName ("com. mysql. jdbc. Driver ");

Connection conn = DriverManager. getConnection ("jdbc: mysql: // localhost: 3306/test", "root", "19850527 ");

System. out. print ("successful ");

}

Catch (Exception e)

{

System. out. print ("fail to connect the database ");

}

}

}

During the first writing, I wrote JAVA. SQL. *; JAVAX. SQL .*;

There have been many strange problems ~

Compile in NETBEANS ~ No com. mysql. jdbc package is displayed ~ I found no errors in all parts ~

Later, I asked for a master leave in the group ~ Experts tell me ~ NETBEANS does not support CLASSPATH

You don't need to read the content of CLASSPATH. 'fuck thing '~ Really big enough ~ If it weren't for the company's requirement to use this IDE, I would have changed it ~

Okay ~ Import the JAR package in the project ~ Later I found that I still didn't run it'

Operation ~~ Throwing an IDE

Handwritten code UE

The error is changed ~ Becomes an exception'

Java. lang. NoClassDefFoundError

Very strange problem ~ Obviously the file is in the current directory ~ The reminder class is not found ~~ Compilation is normal ~~

Later, I found out ~~

In CLASSPATH, set to.; other paths

The "." indicates the current directory ~~ This makes us suddenly realize that ~ The time has reached 11: 00 ~

You can still find the error ~

I am about to crash ~

Continue searching '~

Later I saw my own package ~~ Package com. myapp. struts;

I wonder if this package is not included or the package hides the path strength of this class.

~ Detailed exception prompt is set'

Sure enough ~ The error message "com/myqpp. struts" is not found.

It is OK to delete this statement.

After changing the password to a real password, SUCCESSFUL is output.

Results of one morning ~

Be careful in programming