ClassNotFoundException com.mysql.jdbc.Driver [duplicate]
This question might have asked here number of times . After doing some google search for the above error and doing some update, I can't understand why I'm still getting that error. I've already put my driver-- mysql-connector-java-5.1.5-bin in the classpath:
Java_Home\jre\lib\
Java_Home\jre\lib\ext\
Java_Home\lib
and the code which I'm using to connect to mysql database is:
try{
Class.forName("com.mysql.jdbc.Driver");
Connection con=DriverManager.getConnection("jdbc:mysql://localhost:3306/mail","root","");
Statement stmt = con.createStatement();
ResultSet rs = stmt.executeQuery("select message_body from deadletter");
String dbtime;
while (rs.next()) {
dbtime = rs.getString(1);
System.out.println(dbtime);
}
con.close();
}
catch (SQLException e) {
System.out.println("Connection Failed! Check output console");
e.printStackTrace();
}
}
and the complete stacktrace of the above exception is:
java.lang.ClassNotFoundException: com.mysql.jdbc:Driver
at java.net.URLClassLoader$1.run(URLClassLoader.java:200)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:307)
at java.lang.ClassLoader.loadClass(ClassLoader.java:307)
at sun.misc.Launcher$AppClassLoader.开发者_StackOverflowloadClass(Launcher.java:301)
at java.lang.ClassLoader.loadClass(ClassLoader.java:252)
at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:320)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:169)
at mail.main(mail.java:114)
Now, what's wrong I'm doing here?
If you're facing this problem with Eclipse, I've been following many different solutions but the one that worked for me is this:
Right click your project folder and open up Properties.
From the right panel, select Java Build Path then go to Libraries tab.
Select Add External JARs to import the mysql driver.
From the right panel, select Deployment Assembly.
Select Add..., then select Java Build Path Entries and click Next.
You should see the sql driver on the list. Select it and click first.
And that's it! Try to run it again! Cheers!
I too struggled with the same problem and finally got the solution for it.
Just copy the MySql-Connector.jar
into Tomcat's lib
folder, and then remove the jar from the webapp's lib
folder, and then, run the project.
The most common cause is that you have some conflict in where your classes are loaded from. For example if you have 2 locations and one has JDBC drivers and the other one not then if your classloader loads from the 1st location and some class from the 1st location wants to use the driver - the driver is not there. So look for the duplicate JARs that are using your driver
I have the same problem but I found this after a long search: http://www.herongyang.com/JDBC/MySQL-JDBC-Driver-Load-Class.html
But I made some change. I put the driver in the same folder as my ConTest.java
file,
and compile it, resulting in ConTest.class
.
So in this folder have
ConTest.class
mysql-connector-java-5.1.14-bin.jar
and I write this
java -cp .;mysql-connector-java-5.1.14-bin.jar ConTest
This way if you not use any IDE just cmd in windows or shell in linux.
this ans is for eclipse user......
first u check the jdbc jar file is add in Ear libraries....
if yes...then check...in web Content->web Inf folder->lib
and past here jdbc jar file in lib folder.....
1) Download connector from here https://www.mysql.com/products/connector/
2) Select JDBC driver for mysql
3) click on Platform Independent (Architecture Independent), ZIP Archive
4) Download the file and unzip it
5) (For Eclipse)Click Project->properties-> Java Build Path->Libraries (For Netbeans) right click libraries on left bar-> add jar
6) Click on add external jar
7) select mysql-connector-java-5.1.40-bin.jar
8) Done!
If you are using NetBeans follow the following steps:
- Right click on 'Libraries' and select 'Add Library..'
- Scroll down the list of 'Global Libraries' and select 'MySQL JDBC Driver' and click on 'Add Library'.
What did you put exactly in lib
, jre/lib
or jre/lib/ext
? Was it the jar mysql-connector-java-5.1.5-bin.jar
or something else (like a directory)?
By the way, I wouldn't put it in lib
, jre/lib
or jre/lib/ext
, there are other ways to add a jar to the classpath. You can do that by adding it explicitly the CLASSPATH environment variable. Or you can use the -cp
option of java
. But this is another story.
In NetBeans,
- right click on libraries, select
properties
- select
rub
tab - there you need to add the
mysql-connector-java.jar
and apply
You should download MariaDB connector.
Then:
- Expand your project.
- Right-click on
Libraries
. - Select
Add Jar/Folder
. - Add
mariadb-java-client-2.0.2.jar
which you just downloaded.
Ok, i find solution changing the path of mysql-conector-java.jar to the follow path:
ProjectName/WebContent/Web-inf/lib/mysql-conector-java.jar
So you need to add the conector to project again and delete the previous one.
Most of the possible solution has been covered above. From my experience of this issue, i have placed the mysql-connector-jar in the /WEB-INF/lib folder of the webapp module and it worked fine for me.
In netbean Right click on your project, then you click on Libraries, then Run tab, add library, then select mysql connector
In IntelliJ Do as they say in eclipse "If you're facing this problem with Eclipse, I've been following many different solutions but the one that worked for me is this:
Right click your project folder and open up Properties.
From the right panel, select Java Build Path then go to Libraries tab.
Select Add External JARs to import the mysql driver.
From the right panel, select Deployment Assembly.
Select Add..., then select Java Build Path Entries and click Next.
You should see the sql driver on the list. Select it and click first.
And that's it! Try to run it again! Cheers!"
Here we have to add the jar file in Project Structure -> Libraries -> +(add)
I keep the mysql-connector jar with my project rather than in Javahome. As a result, you can be sure it can be found by being sure its in the local classpath. A big upside is that you you can more the project to another machine and not have to worry about (or forget) to set this up again. I personally like including it in version control.
Ok..May be i can also contribute my solution.. Right click on project -properties -->Deployment assembly...there you need to add the mysql-connector-java.jar and apply it...which makes your prject configured with web-Libraries that has this sql connector...This worked for me.. I hope this works for you guys as well
The only thing that worked for me was downloading the mysql-connector-java-5.0.8-bin.jar directly from the MySQL website:
http://dev.mysql.com/downloads/connector/j/3.1.html
Then if you're using Eclipse paste this mysql-connector-java-5.0.8-bin.jar in the WEB-INF lib folder
If doesn't works try with any of the solutions posted in this link: http://javarevisited.blogspot.com/2012/03/jdbc-javalangclassnotfoundexception.html
I experienced the same error after upgrading my java to 1.8.0_101. Try this: i. Remove the mysql.jar fro your buildpath. ii. Clean the server and project iii. Add the jar file back to the build path.
Worked for me.
Just copy the MySQL JDBC drive jar file and paste it to Tomcat or whatever is the server's lib folder. It works for me.
just copy and paste the mysqlconnector jar to your project folder and then build path it will definitely work.
see to it that the argument of Class. forName method is exactly "com. mysql. jdbc. Driver". If yes then see to it that mysql connector is present in lib folder of the project. if yes then see to it that the same mysql connector . jar file is in the ClassPath variable (system variable)..
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