I'm trying to find the simplest way to compile some Java code via Command Line while including multiple JAR files. This is what I've most recently tried and it does not seem to work.
javac -d bin -sourcepath src -cp lib/* ConfigToExcel.java
The error I'm getting is
javac: invalid flag: lib/FIRST_JAR_FILE.jar
I'm sure there is a simple fix to this issue but I cannot seem to find it.
Try with straight quotes (") with the classpath:
-cp "lib/*"
Related
I have 4 Java-Data:
Common.java
Constants.java
KeywordsEditor.java
ExecutionEngine.java (There is here a Main-Method)
I have successful compiled in Command-Line with this Command from Project-Directory (C:\ProjectDemo\src\main\java\ValueInput)
javac -cp "C:\Users\ABC\selenium-java-2.48.2\selenium-2.48.2\selenium-java-2.48.2.jar;selenium-server-standalone-3.141.59.jar" *.java
I got 4 Data .class in the same Directory. Now i want to run them with this code:
java -cp "C:\Users\ABC\selenium-java-2.48.2\selenium-2.48.2\selenium-java-2.48.2.jar;selenium-server-standalone-3.141.59.jar" ExecutionEngine
But i got Error:
Error: ExecutionEngine main class could not be found or loaded
```
I've tried with some same code else:
```
java -cp "C:\Users\ABC\selenium-java-2.48.2\selenium-2.48.2\selenium-java-2.48.2.jar;libs\*;selenium-server-standalone-3.141.59.jar" ExecutionEngine
java -cp "C:\Users\ABC\selenium-java-2.48.2\selenium-2.48.2\selenium-java-2.48.2.jar;libs/*;selenium-server-standalone-3.141.59.jar" ExecutionEngine
```
And some more, but they don't work. Can somebody help me?
Update
From your comment, I learnt that you have package ValueInput; mentioned in ExecutionEngine.java. Therefore, you should use the switch -d when compiling:
javac -d . -cp "C:\Users\ABC\selenium-java-2.48.2\selenium-2.48.2\selenium-java-2.48.2.jar;selenium-server-standalone-3.141.59.jar" *.java
The option -d . asks the compiler to place the generated class files at the current directory. Now, if you use the command ls in Mac/Unix or dir in Windows, you will see a directory, ValueInput has been created and all the .class files have been placed inside this directory. Learn more about the switches by simply using the command javac
In order to execute ExecutionEngine.class, you can now use the following command:
java -cp ".;C:\Users\ABC\selenium-java-2.48.2\selenium-2.48.2\selenium-java-2.48.2.jar;selenium-server-standalone-3.141.59.jar" ValueInput.ExecutionEngine
You can also check this answer for a similar solution.
Side note: You should follow the Java naming conventions. As per the convention, the name of the package should be something like value.input.
Original answer
The root cause of the problem is using only jars with -cp. You missed realizing that your ExecutionEngine.class is not in the jars; rather it is at the current directory which is denoted by a dot (.) which you missed to include in the classpath.
Thus, the correct command will be:
java -cp ".;C:\Users\ABC\selenium-java-2.48.2\selenium-2.48.2\selenium-java-2.48.2.jar;selenium-server-standalone-3.141.59.jar" ExecutionEngine
It doesn't matter where you put . i.e. the current directory e.g. the following will also work for you:
java -cp "C:\Users\ABC\selenium-java-2.48.2\selenium-2.48.2\selenium-java-2.48.2.jar;selenium-server-standalone-3.141.59.jar;." ExecutionEngine
Note for Mac:
The separator used for this purpose in Mac is : instead of ; e.g.
javac -cp mysql-connector-java-5.1.49.jar MysqlDemo.java
java -cp mysql-connector-java-5.1.49.jar:. MysqlDemo
Note for Java-11 onwards:
Java-11 allows launching Single-File Source-Code programs without compiling e.g.
java -cp mysql-connector-java-5.1.49.jar MysqlDemo.java
You can learn more about it from this article.
Here is the structure of my project:
MyProject
-lib
-mp3agic-0.9.0.jar
-src
-com.company
-Main.java
Inside Main, I import the content of mp3agic:
import com.mpatric.mp3agic.*;
From MyProject, I compile the class using:
javac -cp "lib/*" src/com/company/Main.java
From MyProject/src, I try to run the program with:
java -cp . com/company/Main
and I get the following error:
Exception in thread "main" java.lang.NoClassDefFoundError: com/mpatric/mp3agic/InvalidDataException
Apparently, the jdk can not find the dependencies from the lib folder when running the class, albeit this problem doesn't occur when compiling.
I guess there's a problem with the syntax of the command, but I just can't find it.
Can you please help me?
EDIT: I solved the problem, moving the lib folder under src and then running:
C:\MyProject\src>javac -cp "lib/*" com/company/Main.java
C:\MyProject\src>java -cp .;"lib/*" com/company/Main
Now, the code compiles and executes without any issue.
HOWEVER, if I leave lib under the project root, this is what happens:
C:\MyProject>javac -cp "lib/*" src/com/company/Main.java
C:\MyProject>java -cp .;"lib/*" src/com/company/Main
Error: Could not find or load main class src.com.company.Main
WHY?
You should use maven or gradle or you'll have to say which console are your using, and which operating system -if you don't know what a console is, you'll first have to google for that before messing with javac directly- But if you insist:
for Linux, OSX, any UNIX-like:
javac -cp ".:lib/mp3agic-0.9.0.jar" src/com/company/Main.java
for Windows:
javac -cp ".;lib/mp3agic-0.9.0.jar" src/com/company/Main.java
To run under windows:
java -cp .;lib\mp4agic-0.9.0.jar com.company.Main
You may need to use slash (/) instead of backslash depending of which console you're using. Or just try "/" or "\" and see what works for you.
If you still get class not found exception, then the issue is not related with classpath or java command but on your code (hard to say, without seeing the code).
java.exe -classpath {path} Main
I think you have to add classpath also and when run the program(not only compile)
I'm trying to compile some java code for hadoop and need to know what classpath I need to specify. For cloudera I use this below but what do I use for a MapR installation? Surprisingly I could only find how to set the classpath in google, not what to set it to.
javac -classpath "/opt/cloudera/parcels/CDH-4.6.0-1.cdh4.6.0.p0.26/lib/hadoop/client/*" mr.java -d mr
Found the answer by trial and error. Oddly google is very silent on this and all the books and examples I've read appear to assume this is too obvious to bother printing.
mkdir MyClass
javac -classpath "/opt/mapr/hadoop/hadoop-0.20.2/lib/*" MyClass.java -d MyClass
jar -cvf MyClass.jar -C MyClass .
Additionally, if you want the hive libraries, eg for compiling a hive UDF:
javac -classpath "/opt/mapr/hadoop/hadoop-0.20.2/lib/*:/opt/mapr/hive/hive-0.12/lib/*" MyClass.java -d MyClass
EDIT: one thing I would add is make sure you put quotes around the path, otherwise linux expands it on the command line which is not what you want. The * in the path needs to be passed to java as is.
I'm trying to compile a java program that uses multiple .jar files but am experiencing compile problems. I also can't copy the full output from the virtual machine, but i'll try to post the relevant information.
javac -g Model.java
This ends up getting 33 errors (GL11 cannot find symbol)
javac -g -classpath /media/sf_vm_source/java/java_pkg/lwjgl-*/jar/lwjgl.jar Model.java
This ends up with 5 errors (GL11 is found) [5 errors are from other jars but i'm trying to get it to work with 2 .jars first]
javac -g -classpath /media/sf_vm_source/java/java_pkg/lwjgl-*/jar/lwjgl.jar:/media/sf_vm_source/java/java_pkg/lwjgl-*/jar/lwjgl_util.jar Model.java
This ends up with 33 errors again (GL11 cannot find symbol)
Other info:
sf_vm_source is auto-mounted by virtualbox and has 777 permissions recursively including /media.
Moving all the jar files to a local lib file and using wildcards removes the compile error, but of course has its own issues.
If you are using the relative path in your classpath, then you may have to add the current path(using a dot(.)) to all the jars path. Something like this:
javac -g -classpath ./media/sf_vm_source/java/java_pkg/lwjgl-*/jar/lwjgl.jar Model.java
Also the use of wildcard lwjgl-* may not work here
Hey I got this problem when running a java program through my cmd.
I use to external libraries : lwjgl.jar and slick-util.jar
when I compile
javac -d bin -sourcepath src -cp ;lib/lwjgl.jar;lib/slick-util.jar src/*.java
everything works fine
but when I try to run it
java -cp bin .;lib/lwjgl.jar;lib/slick-util.jar; Game
I get this error
Error: could not find or load main class .;lib.lwjgl.jar;lib.slick-util.jar;
Replace the space in the run command classpath with a classpath separator
java -cp bin;.;lib/lwjgl.jar;lib/slick-util.jar; Game
^
as an improvement to the run command you could use a classpath wilcards, for example
java -cp ".;bin;lib/*" Game
It is important to use quotes under Windows for this option