如何在 Windows 10 中使用命令提示符在编译和运行时包含第三方 jar 文件？

Question

I'm trying to understand the inclusion of third party jar files in a java project using only the command line in Windows 10.

Specifically, I try to include the file json-20200518.jar in my "project" so that I can use the java object JSONObject in the project.

My java file:

package com.mypackage.example;

import org.json.JSONObject;

class Example {
    public static void main(String[] args) {
        // ... program logic
    }
}

location of my java file (Examp.java):

./com/mypackage/example

location of jar file:

./jars

using cmd win10 I compile:

javac -cp "C:\\Users\\pfort\\Desktop\\java\\jars\\json-20200518.jar" "C:\\Users\\pfort\\Desktop\\java\\com\\mypackage\\example\\Examp.java"

compilation is successful.

Run:

java -cp "C:\\Users\\pfort\\Desktop\\java\\jars\\json-20200518.jar" com.mypackage.example.Examp

I get a report:

Error: Could not find or load main class com.mypackage.example.Pokus Caused by: java.lang.ClassNotFoundException: com.mypackage.example.Pokus

Second attempt:

java -cp "C:\\Users\\pfort\\Desktop\\java\\jars\\json-20200518.jar" "C:\\Users\\pfort\\Desktop\\java\\com\\mypackage\\example\\Pokus"

But the same error message comes back to me. Where am I going wrong?
Is it the wrong structure?
I don't get it, the compilation is successful but the run does not work.

Answer 1

The compiled Examp.class file isn't part of json-20200518.jar , so you'll need to add the directory containing it to the command line. Assuming it's the current directory ( . ):

java -cp "C:\Users\pfort\Desktop\java\jars\json-20200518.jar;." com.mypackage.example.Examp