I have created a Java application that uses a database, and I now want to build it into a jar file and make it so that the database works without NetBeans. I thought NetBeans would automatically include the database, but it doesn't.
The files that NetBeans include in the 'dist' folder when I build it look like this:
dist
lib
derby.jar (Executable Jar File)
derbyclient.jar (Executable Jar File)
README
WordFinder.jar (Executable Jar File)
Everything except the database-related code works when I launch the WordFinder.jar file after closing NetBeans.
I noticed that the database is using 'org.apache.derby.jdbc.ClientDriver', and I'm wondering, does that need to be 'org.apache.derby.jdbc.EmbeddedDriver' in order for it to include the database?
Are there any files that I need to include? I'm new to Java databases, so try to keep the instructions simple.
You need to start the database server in you computer, for doing that you need to go to your derby path (C:\Program Files\Java\jdk1.8.0_45\db\bin) and run the startNetworkServer.bat file
I may be a year late but seeing the comments, I'm assuming the issue hasn't been resolved yet. I had the same problem and would like to show how I worked around it. Note I'm not using an embedded derby database.
1) I changed my connection string. Instead of the usual "jdbc:derby://localhost:1527/myDB;create=true;...." , I put the exact location of the database which can be found usually under C:\Users\myPC\.netbeans-derby\myDB
2) Clean and build the project which should give you the "dist" folder which would include the jar file of the project together with the "lib" folder.
3) Start the StartNetworkServer.bat which is located in the bin folder under derby folder. A cmd would show that will say something "Apache Derby Network Server blah blah blah started and ready to accept connections on port 1527"
4) After doing those, run the jar file and it should run even with the netbeans IDE closed.
That's about it. That's how I got mine to work without opening Netbeans IDE. Hope it helps.
Related
There is a VERY similar question to mine but in my case I don't have any duplicate jars in my build path, so the solution does not work for me. I've searched google for a couple of hours now, but none of the solutions I've found there actually resolve my issue. I'm creating a web site with some database connectivity for a homework. I'm using a MySQL database, developing in Eclipse and running on Windows.
I keep getting java.lang.ClassNotFoundException: com.mysql.jdbc.Driver with the following code:
import java.sql.*;
//...
public void someMethodInMyServlet(PrintWriter out)
{
Connection connection = null;
PreparedStatement query = null;
try {
out.println("Create the driver instance.<br>");
Class.forName("com.mysql.jdbc.Driver").newInstance();
out.println("Get the connection.<br>");
connection = DriverManager.getConnection("jdbc:mysql://localhost:3306/test", "root", "secret");
query = connection.prepareStatement( "SELECT * FROM customers");
//...
} catch (Exception e)
{
out.println(e.toString()+"<br>");
}
}
//...
When I run the above code I get the following output:
Create the driver instance.
java.lang.ClassNotFoundException: com.mysql.jdbc.Driver
It doesn't get past the Class.forName... line and I can't figure out why! Here is what I did:
Download mysql-connector.
Put it in my MySQL folder C:\Program Files\MySQL\mysql-connector-java-5.1.12\mysql-connector-java-5.1.12-bin.jar.
Opened the project properties in Eclipse.
Add External Jar to my Build Path and I selected mysql-connector-java-5.1.12-bin.jar.
Every time I attempt to use the servlet I get the same error regardless if I have the jar in there or if I don't. Could you help me figure this out?
As for every "3rd-party" library in flavor of a JAR file which is to be used by the webapp, just copy/drop the physical JAR file in webapp's /WEB-INF/lib. It will then be available in webapp's default classpath. Also, Eclipse is smart enough to notice that. No need to hassle with buildpath. However, make sure to remove all unnecessary references you added before, else it might collide.
An alternative is to install it in the server itself by dropping the physical JAR file in server's own /lib folder. This is required when you're using server-provided JDBC connection pool data source which in turn needs the MySQL JDBC driver.
See also:
How to add JAR libraries to WAR project without facing java.lang.ClassNotFoundException? Classpath vs Build Path vs /WEB-INF/lib
How should I connect to JDBC database / datasource in a servlet based application?
Where do I have to place the JDBC driver for Tomcat's connection pool?
JDBC CLASSPATH Not Working
Since you are running it in servlet, you need to have the jar accessible by the servlet container. You either include the connector as part of your application war or put it as part of the servlet container's extended library and datasource management stuff, if it has one. The second part is totally depend on the container that you have.
The others are right about making the driver JAR available to your servlet container. My comment was meant to suggest that you verify from the command line whether the driver itself is intact.
Rather than an empty main(), try something like this, adapted from the included documentation:
public class LoadDriver {
public static void main(String[] args) throws Exception {
Class.forName("com.mysql.jdbc.Driver");
}
}
On my platform, I'd do this:
$ ls mysql-connector-java-5.1.12-bin.jar
mysql-connector-java-5.1.12-bin.jar
$ javac LoadDriver.java
$ java -cp mysql-connector-java-5.1.12-bin.jar:. LoadDriver
On your platform, you need to use ; as the path separator, as discussed here and here.
Place mysql-connector-java-5.1.6-bin.jar to the \Apache Tomcat 6.0.18\lib folder. Your problem will be solved.
What you should not do do (especially when working on a shared project)
Ok, after had the same issue and after reading some answers here and other places. it seems that putting external lib into WEB-INF/lib is not that good idea as it pollute webapp/JRE libs with server-specific libraries - for more information check this answer"
Another solution that i do NOT recommend is: to copy it into tomcat/lib folder. although this may work, it will be hard to manage dependency for a shared(git for example) project.
Good solution 1
Create vendor folder. put there all your external lib. then, map this folder as dependency to your project. in eclipse you need to
add your folder to the build path
Project Properties -> Java build path
Libraries -> add external lib or any other solution to add your files/folder
add your build path to deployment Assembly (reference)
Project Properties -> Deployment Assembly
Add -> Java Build Path Entries
You should now see the list of libraries on your build path that you can specify for inclusion into your finished WAR.
Select the ones you want and hit Finish.
Good solution 2
Use maven (or any alternative) to manage project dependency
Just follow these steps:
1) Install eclipse
2) Import Apache to eclipse
3) Install mysql
4) Download mysqlconnector/J
5) Unzip the zipped file navigate through it until you get the bin file in it. Then place all files that are present in the folder containing bin to C:\Program Files\mysql\mysql server5.1/
then give the same path as the address while defining the driver in eclipse.
That's all very easy guys.
If the problem still persists,
Put the-
mysql-connector-java-5.0.8-bin jar in a place inside your Tomcat->lib->folder (No matter where you've installed your Tomcat). And change your environmental variable (Done by clicking Properties of Mycomputer -Advanced system settings- Environmental variables-And set a new variable name & variable values as the place where your lib file resides.Dont forget to enter a ; at the end of the path)
If still problem persists
Try downloading commons-collections-2.0.jar (http://www.docjar.com/jar_detail/commons-collections-2.0.jar.html) and paste the jar in the same place where your mysql jar resides (ie) inside Tomcat-lib.
Clean your project-Stop your server- Finally try to run.
Many times I have been facing this problem, I have experienced ClassNotFoundException.
if jar is not at physical location.
So make sure .jar file(mysql connector) in the physical location of WEB-INF lib folder. and
make sure restarting Tomcat by using shutdown command in cmd.
it should work.
The only solution worked for me is putting the .jar file under WEB-INF/lib . Hope this will help.
assuming your project is maven based, add it to your POM:
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<version>5.1.26</version>
</dependency>
Save > Build > and test connection again. It works! Your actual mysql java connector version may vary.
Put mysql-connector-java-5.1.38-bin.jar to the C:\Program Files\Apache Software Foundation\Tomcat 7.0\lib folder.by doing this program with execute
My issue was a little different. Instead of jdbc:oracle:thin:#server:port/service i had it as server:port/service.
Missing was jdbc:oracle:thin:# in url attribute in GlobalNamingResources.Resource. But I overlooked tomcat exception's
java.sql.SQLException: Cannot create JDBC driver of class 'oracle.jdbc.driver.OracleDriver' for connect URL 'server:port/service'
for this error:
java.lang.ClassNotFoundException: com.mysql.jdbc.Driver
you need to:
Import java.sql.*;
Import com.mysql.jdbc.Driver;
even if its not used till app running.
I've run .jar files before, but I've encountered a "different" situation, and I'm not sure what to do. I'd appreciate if someone could help me out.
Previously, I programmed with Java 6 and Eclipse Juno exported all my programs to runnable jar files. I'd get a .jar file that I could run by just double clicking on it. The files always looked something like this (note the jar file icon):
Recently, I wrote a program in Java 8 with Eclipse Luna (Release 4.4.0) and exported it to a runnable jar file, and I got something different (note the different file icon):
It no longer runs when I double click it. Instead, my computer uncompresses the jar, as it would a zip file. I tried running it from terminal. I cd'd to the directory and typed
java -jar graph3D.jar
I got the following error message:
Error: Unable to access jarfile graph3D.jar
After uncompressing the jar file, I found a folder named META-INF with the manifest file, MANIFEST.MF in it. It was the only file that seemed to resemble an executable file. Do I have to do something with that?
Could someone explain how I can run the second jar file graph3D.jar? Is it something new with Java 8, or something different about Eclipse Luna, or something else?
(Both programs run fine in Eclipse, by the way)
Thanks for your time and help.
Edit:
Below was the dialog box Eclipse displayed if anyone is interested.
Selecting "Use .jar;.zip" makes the filename "graph3D.jar;.jar;*.zip" .
Selecting "Use .zip" makes the filename "graph3D.jar;*.zip"
Selecting "Cancel" doesn't let you go forward.
You'd have to manually delete the extra file extension.
Somehow when you exported the file, the filters for the file dialog box (*.jar;*.zip) got attached to the filename, which is graph3D.jar;*.jar;*.zip, not graph3D.jar. Java can't find it because it doesn't have the name you supplied. Rename the file and pay close attention next time you export; either you fat-fingered something, or you're triggering a significant bug that needs fixing.
I recommend that you will access the build folder after you've built your project on the IDE under your project folder (in your workspace) and copy both the libraries folder and the .jar and post them wherever you want the program to be "installed", you'll then have an executable jar that should run smoothly without problems, just as I said don't forget the lib folder.
I think there is nothing new in Java 8 related with the running jar, I guess you need to check the the Eclipse export issues, it seems your classes are missing from your second jar file.
I have tomcat installed at "C:\Program Files\apache-tomcat-7.0.27"
I have eclipse installed at "C:\Program Files\eclipse"
And I have the workspace located at "C:\workspace"
I'm using "Java perspective", created a "Java Project" with the default output folder as "helloWorld/web/WEB-INF/classes".
The structure of the project goes like this:
-helloWorld
---src
-----servlets
-------hello.java
-------world.java
---web
-----WEB-INF
-------jsp
---------hello.jsp
---------world.jsp
-------lib
-------web.xml
---helloWorld.xml
---record.txt
doPost() in hello.java generate a random number, and write it to a text file "record.txt".
doPost() in world.java open the text file "record.txt" and read a number.
The system is working, but what I originally put in the record.txt file in eclipse project never get changed, and I'm sure that what world.java read from the file is exactly what hello.java generated.
I checked "C:\Program Files\apache-tomcat-7.0.27\work\Catalina\localhost\helloWorld", and only jsp files are there.
I then tried restart tomcat and reload and even undelopy and deploy again, but the previous generated number is still there. I didn't try restart computer.
My question is where is the record.txt file? It is definitely not the one in the eclipse project.
If you use a relative file path in your Java code then it will not be relative to your webapp it will be relative to where the process running Tomcat was started. Therefore you might find your file in the Tomcat bin directory or somewhere similar.
If you want to create a file relative to your webapp then you need to obtain the path to your webapp, which you can do by calling getServletContext().getRealPath("") in your Servlet.
Eclipse deployed projects are run in temp folder. the path looks some thing like this... tmp0/conf/catalina/localhost/projectname.....context.xml of servers might help you in this..
i suggest u should go for an absolute path....i faced same problem while using eclipse...That time i had to even provide the link to the user...
Check your webapps folder for a folder with the same name as your project.
C:\Program Files\apache-tomcat-7.0.27\webapps
Here you will find the exact folder structure and your record.txt file as well.
Hope this helps!
I use sqlite in my java application. When I run it from Netbeans, it works well. The sqlite db file is located in the root project directory (same level as build.xml).
This is the code to access the database file:
DriverManager.getConnection("jdbc:sqlite:database.db");
However, when I build the project, and run the jar file outside netbeans, I always get this error: no such table: table_name
My question: where is the correct location to put the "sqlite db" file? Is it possible to package it inside the JAR file?
I have tried to package my application into a single JAR file (similar to Eclipse's FatJar), but I still get that error. In this case I modify the build.xml as explained in this blog:
Netbeans single JAR
I also tried to create a database folder in the src directory and then put the db file inside the folder (src/database/database.db) and access it using
DriverManager.getConnection("jdbc:sqlite:src/database/database.db");
I can run it inside netbeans. But when I run it outside, I got this error:
path to 'src/database/database.db':C:\Windows\system32\src' does not exist
I know there are similar questions to this in stackoverflow, but most of them don't have a concrete solution. Let me know if someone has found a better one.
Thanks a lot.
Problem solved!
I made a mistake in the way I execute the JAR file. Previously I run the JAR file by right click on it and open it with Java SE binary. I need to do this because in my PC the default program to open JAR file was set to another software.
It turned out that I have to set the default program to Java SE Binary and the double click the JAR file in order to run my application. Using this way I can run and access the sqlite db file without a problem.
I hope this can help others who may get the same problem as I had.
probably you need to point your app to include your app base directory in the classpath.
the command to run your app should be something like:
java -cp . YourAppMainClass
the "-cp . " is the command option that tells java to include current directory in the classpath.
I have a 3 projects under Eclipse : 1-CLIENT, 2-COMMON, 3-SERVER. The server project contains everything related to database managment (i.e. DAO...). I'm using hibernate and annotation for this project to access database. The common project contains also some objects commonly used by both the Server and the Client. Some of these objects are from the database. My Server project contains as well the HibernateUtils class that load the configuration file "hibernate.cfg.xml".
When I run the project under Eclipse, no problem, everything is going smoothly. Now comes the deployment... I'm exporting the server as a runnable jar file under Eclipse and the common project as a lib file. in the server jar file, I have the file "hibernate.cfg.xml".
When I launch the program, I'm ending up with an exception
Caused by: org.hibernate.HibernateException: /hibernate.cfg.xml not found
I've tried to force the filename in the configuration process using new AnnotationConfiguration().configure("XXXX/hibernate.cfg.xml"), but nothing is working !
Even when I copy the debug command line used to launch the program and paste it under a command dos window, it's not working...
What am I missing there ?
Hibernate searches for its configuration in places addressed in CLASS_PATH. i suggest you put your hibernate.cfg.xml in your source folder. this often prevent likely problems.
Another suggestion! don not export your project using eclipse export wizard, try to create an ant file to do so, or maven if you can...