I am using CMake to compile jar file with add_jar command. Problem is that when I try to add INCLUDE_JARS to specify dependency to external jar, the code will not run. Here is the code example:
add_jar(testJar
SOURCES
sources/com/test/Main.java
INCLUDE_JARS
${CMAKE_SOURCE_DIR}/extern/org.json/json-20171018.jar
ENTRY_POINT com.test.Main
)
Running the testJar with "java -jar testJar.jar" gives me the following error:
Exception in thread "main" java.lang.NoClassDefFoundError: org/json/JSONException
The org.json jar should be in classpath, right? Adding manifest file with classpath solves the problem but is there way to do this without the manifest file?
And yes, I would use maven or gradle for building but as of restrictions in the project I cannot do that :)
The option INCLUDE_JARS only makes sure that the given external jar is added to the class path upon compilation of the given Java source files. The jar file is neither copied to the build directory nor is it added to the jar file generated by add_jar.
If inclusion of the external jar in the Manifest file is not an option for you, manually add it to the class path upon running the testJar, i.e.:
java -cp path/to/json-20171018.jar -jar testJar.jar
Related
I try to create a Minecraft Plugin (it's my first one) and I can't fix this error:
So, the plugin compiles good but when the code has to execute this code :
BCrypt.checkpw(mdp, result.getString("mdp"))
that come from the lib org.mindrot.BCrypt, I have this error :
Caused by: java.lang.NoClassDefFoundError: org/mindrot/BCrypt
But, when I open my JAR with WinRAR, there is my lib bcrypt (so it's well export). And it's also in my .classpath.
Can you help me ?
Thanks.
There are several ways to configure the CLASSPATH when launching a java application via the java command. According to what you posted so far, I would use the -classpath flag:
java -classpath spigot.jar;jbcrypt.jar class.containing.main.method.MyMain
Alternatively, you could modify the MANIFEST in file spigot.jar. Refer to Adding Classes to the JAR File's Classpath.
Or you could copy jbcrypt.jar to the directory pointed to by the java System property "java.ext.dirs".
After converting my java program to executable jar file using commands in command prompt in windows 10,while executing jar file I am getting error:
Could find or load main class Combine.class" caused
by:java.lang.ClassNotFoundException:Combine.class
My jdk-11.0.1 has javamail api and excelapi.While executing I have set my classpath as:
classpath=%classpath%;C:\Program Files\Java\jdk-11.0.1\javamail_api\javax.mail-1.6.2.jar;C:\Program Files\Java\jdk-11.0.1\javamail_api\activation.jar;C:\Program Files\Java\jdk-11.0.1\jexcelapi\jxl.jar;.;
It was compiling and executing properly but after converting to executable jar file it is not running and giving above error.
Any help would be appreciated.
Thank you
The clue is in the exception message. It is trying to load a class with the name Combine.class. But the classes real name is Combine.
You have created the JAR file incorrectly.
echo Main-Class: Combine.class > manifest.txt
jar cmf manifest.txt FinalExecutable.jar Combine.class
If Combine is in the default package (i.e. it doesn't have a package statement) then the above should be:
echo Main-Class: Combine > manifest.txt
jar cmf manifest.txt FinalExecutable.jar Combine.class
If Combine is declared in package foo.bar, then the above should be.
echo Main-Class: foo.bar.Combine > manifest.txt
jar cmf manifest.txt FinalExecutable.jar foo/bar/Combine.class
and you need to be in the directory above the foo directory.
NB: the "Main-Class" attribute in the manifest must be a Java fully qualified class name, NOT a filename or file pathname.
It also should be noted that the CLASSPATH environment variable and the -cp argument will be ignored when you run a JAR using java -jar .... If your executable JAR depends on other JAR files, you should either combine them (to create a shaded JAR) or you should add a "Class-Path" attribute to the manifest; see https://docs.oracle.com/javase/tutorial/deployment/jar/downman.html
Finally, my advice would be to use a build tool (e.g. Maven) to compile your code, create the executable JAR file, etc rather than doing it by hand.
So I'm still a noob in Java and I'm experimenting around with a few things.
I recently created a .jar file for my class using jar cvf <name>.jar <source files> and then used that jar to compile my driver class (javac -cp <name>.jar Driver.java) though how do I now run that class using the jar?
I've tried the following 2 commands:
java Driver and,
java -cp <name>.jar Driver.
The first gives me a NoClassDefFoundError for the class used, whereas the latter just gave me a single line error.
Error: Could not find or load man class Driver
What am I doing wrong? Is it possible I'm confusing this for something else?
I'm trying to do as much as I can without the use of any IDE.
You should put jar file and compiler output into classpath and specify main class:
java -classpath "<name.jar>;classes" Driver
EDIT (thanks to Kayaman):
If you are running command from linux/unix you have to use ":" as separator (in Windows works ";"). "classes" is a path to folder containing compiler output.
When creating an executable jar ( jar which contain a class with the main method) you should tell the jar which is the mainClass to be executed and for that you should create a file called 'Manifest.mf'.
The file should contain this:
Main-Class: MyPackage.MyClass
And when creating the jar you should use this to include your manifest:
jar cfm MyJar.jar Manifest.mf MyPackage/*.class
And for launching your jar :
java -jar MyJar.jar
I need help including imported jar files into my java program in Linux. Here is the program:
import java.sql.*;
public class CreateCoffees
{
public static void main(String args[])
{
try {
Class.forName("com.ibm.db2.jcc.DB2Driver");
}
catch(java.lang.ClassNotFoundException e) {
System.err.print("ClassNotFoundException: ");
System.err.println(e.getMessage());
System.exit(1);
}
}
}
In order to execute Class.forName("com.ibm.db2.jcc.DB2Driver"); I need two .jar files added into the classpath:
db2jcc_license_cu.jar
db2jcc4.jar
I put these jar files into the same directory as my CreateCoffees.java file, then compile and run it like this:
javac CreateCoffees.java
java CreateCoffees
But I got this error
ClassNotFoundException: com.ibm.db2.jcc.DB2Driver
Then I tried the "-classpath" option
javac -classpath ./db2jcc_license_cu.jar:./db2jcc4.jar CreateCoffees.java
java -classpath ./db2jcc_license_cu.jar:./db2jcc4.jar CreateCoffees
but got this
Exception in thread "main" java.lang.NoClassDefFoundError: CreateCoffees
Caused by: java.lang.ClassNotFoundException: CreateCoffees
How to I include those jar files into a my runnable jar so I can run it with java -jar myjar.jar ?
Try this
java -classpath ./db2jcc_license_cu.jar:./db2jcc4.jar:. CreateCoffees
when you use -classpath it looses current directory from classpath so it needs . in classpath as well explicitly
How to include the jars of your project into your runnable jar:
I'll walk you through it step by step with Eclipse Version: 3.7.2 running on Ubuntu 12.10. I'll also show you how to make the build.xml so you can do the ant jar from command line and create your jar with other imported jars extracted into it.
Basically you ask Eclipse to construct the build.xml that imports your libraries into your jar for you.
Fire up Eclipse and make a new Java project, make a new package 'mypackage', add your main class: Runner Put this code in there.
Now include the mysql-connector-java-5.1.28-bin.jar from Oracle which enables us to write Java to connect to the MySQL database. Do this by right clicking the project -> properties -> java build path -> Add External Jar -> pick mysql-connector-java-5.1.28-bin.jar.
Run the program within eclipse, it should run, and tell you that the username/password is invalid which means Eclipse is properly configured with the jar.
In Eclipse go to File -> Export -> Java -> Runnable Jar File. You will see this dialog:
Make sure to set up the 'save as ant script' checkbox. That is what makes it so you can use the commandline to do an ant jar later.
Then go to the terminal and look at the ant script:
So you see, I ran the jar and it didn't error out because it found the included mysql-connector-java-5.1.28-bin.jar embedded inside Hello.jar.
Look inside Hello.jar: vi Hello.jar and you will see many references to com/mysql/jdbc/stuff.class
To do ant jar on the commandline to do all this automatically: Rename buildant.xml to build.xml, and change the target name from create_run_jar to jar.
Then, from within MyProject you type ant jar and boom. You've got your jar inside MyProject. And you can invoke it using java -jar Hello.jar and it all works.
I have a problem creating and executing a JAR file. I have already made a JAR file, but when I execute it with java -jar, I am getting an error Error: could not find and load main class ... I make a JAR file with jar cvfm, but I execute it from C:\Program Files\Java\jdk1.70\
What's wrong with this?
To create an executable jar file you have to specify the entry point to the jar.Like this:
jar -cvfe "jar file name" "Main Class Name(Ex com.test.MainTest)" "Files to be included in the jar"
If you already have a jar file, you can update the manifest file by creating an "additions" file and running the command to include the main class :
Main-Class: Classname
and run command:
jar ufm "jarfilename" "additions manifest"
Maybe an entry in your manifest is missing? You have to add your MainClass to the MANIFEST.MF - the entry needed is Main-Class: classname
For mor informations see here
Whenever we create the jar file , we pass the main-class parameter in Manifest.mf that is embed in the jar .
you have missed that part and now when you are executing its not able to identify the main class to execute from
http://www.skylit.com/javamethods/faqs/createjar.html might help