compile and run java with jar files

Question

I'm trying to compile a java file that uses multiple jar files as imports. the command that I have used to compile my code :

javac -cp jackson-databind-2.12.1.jar:jackson-core-2.12.1.jar:jackson-annotations-2.12.1.jar TestRunner.java

as a result two .class files are created : TestRunner.class and TestRunner$1.class

then I run the command :

java TestRunner

but it throws an error that says:

Error: Unable to initialize main class TestRunner Caused by: java.lang.NoClassDefFoundError: com/fasterxml/jackson/core/type/TypeReference

I have included all the required libraries in the javac command, tested it with the IDE and it works fine. I have tried other versions of the jackson library but I'm stuck with the same error.

@MarcStroebel it gives me an error : Could not find or load main class TestRunner Caused by: java.lang.ClassNotFoundException: TestRunner — Ahmed Ferjani, Apr 20 '21 at 12:30
Please check this thread https://stackoverflow.com/questions/9395207/how-to-include-jar-files-with-java-file-and-compile-in-command-prompt/61969540#61969540 — pratap, Apr 20 '21 at 12:35
add the folder containing the compiled class files also to cp option — Marc Stroebel, Apr 20 '21 at 12:38
@MarcStroebel, thanks it worked now, i have changed in the command by adding the folder containing the compiled class final : java -cp .:jackson-databind-2.12.1.jar:jackson-core-2.12.1.jar:jackson-annotations-2.12.1.jar TestRunner — Ahmed Ferjani, Apr 20 '21 at 12:41
@MarcStroebel added your precision to my answer, forgot about that (it's been quite a long time since I have to write a classpath by hand) — Valentin Rocher, Apr 21 '21 at 06:28

Valentin Rocher · Accepted Answer · 2021-04-21T06:27:33.337

1

You need to specify the classpath when running your code, by using the same -cp args that you used when compiling, plus the folder where your compiled class is in.

In your cas that would mean something like java -cp .:jackson-databind-2.12.1.jar:jackson-core-2.12.1.jar:jackson-annotations-2.12.1.jar TestRunner

The libs you specified are not included in the .class files generated, so Java still needs them to understand how to call the code that's not coming from your class file.

edited Apr 21 '21 at 06:27

answered Apr 20 '21 at 12:04

Valentin Rocher

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when running : java -cp jackson-databind-2.12.1.jar:jackson-core-2.12.1.jar:jackson-annotations-2.12.1.jar TestRunner , gives me an error : Error: Could not find or load main class TestRunner Caused by: java.lang.ClassNotFoundException: TestRunner – Ahmed Ferjani Apr 20 '21 at 12:29
@AhmedFerjani I've edited my answer to include the fact that you should add your compiled class also – Valentin Rocher Apr 21 '21 at 06:27

compile and run java with jar files

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