无法使用classpath选项从cmd运行此程序

Question

this is a beginner question. I am having a problem running my java program from command line. I am using Windows10. The problem is the following. I have a folder named "folder1", which is located o the dekstop of my computer. So the full path would be C:\\Users\\Ioanna\\Desktop\\folder1 Inside that folder I have created a second folder which I named folder2. so the path to this would be C:\\Users\\Ioanna\\Desktop\\folder1\\folder2

Inside folder2 I have a java file named example.java I want to compile it and run this file with setting the -classpath option through cmd. I dont want to set the path or to add the folder to tha path from environment variables.

I am trying

C:\Users\Ioanna\javac -cp C:\Users\Ioanna\Desktop\folder1\folder2 example.java

but it says file not found. I tried several other alternatives, but I can't seem to find how to compile successfully the program.

Answer 1

java expects the path of the file(s) to compile. And example.java is not in the current folder (C:\\Users\\Ioanna).

Use

javac Desktop\folder1\folder2\example.java

Answer 2

Code compilation (to bytecode) and code execution are two separate steps, in Java.

First, compile your .java to obtain the corresponding .class file (I'm assuming your folder paths are right) :

C:\Users\Ioanna\javac C:\Users\Ioanna\Desktop\folder1\folder2\example.java

This will give you example.class in that same folder.
Next, run that class (provided it has a main() method):

C:\Users\Ioanna\java -cp C:\Users\Ioanna\Desktop\folder1\folder2 example