不只是java.lang *包时如何在Windows上运行compilr.com java .jar可执行文件

Question

I'm starting to code in Java in spare work time. Problem is everything is locked down and I'm kinda new to ask IT department to install ide or javac at least to me(im not in IT) so Im using Compilr.com which is quite awesome. Yet I tried to save and run the Hello world code already precoded there:

public class ReadFile
{
    public static void main(String args[]) 
    {
        System.out.println("Hello World from Compilr!");
        System.out.println("Press any key to continue.");
        try {
            System.in.read();
        } catch (Throwable t) {}
    }
}

Then open windows cmd and run java -jar HelloWorld.jar Which Works. Then I tried to build and run this code which throws the typical error that I havent properly setup classpath or some manifest made:

import java.io.*;

public class ReadFile{
    public static void main(String[] args){
        try {

            FileReader input = new FileReader(args[0]);

            BufferedReader bufRead = new BufferedReader(input);

            String line;    
            int count = 0;  


            line = bufRead.readLine();
            count++;

            // Read through file one line at time. Print line # and line
            while (line != null){
                System.out.println(count+": "+line);
                line = bufRead.readLine();
                count++;
            }

            bufRead.close();

        }catch (ArrayIndexOutOfBoundsException e){

            System.out.println("Usage: java ReadFile filename\n");          

        }catch (IOException e){
            // If another exception is generated, print a stack trace
            e.printStackTrace();
        }

    }// end main
}

The thing it only generates a jar file so I dont have much of choice for compiling. How do I please make working code with all the available non-core java clasess? /At home I get error even on the helloworld program: Error:Could not find or load main class Program.

Answer 1

You should be able to install both JDK with Netbeans and Eclipse in a local directory without admin rights. While it will be interesting to find out why compilr.com generated jar does not work for you for any serious work you will need a development environment.