title: How do I run a Java program from the command line on Windows?
body: <p>I'm trying to execute a Java program from the command line in Windows. Here is my code:</p>
  
  <pre><code>import java.io.File;
  import java.io.FileInputStream;
  import java.io.FileOutputStream;
  import java.io.IOException;
  import java.io.InputStream;
  import java.io.OutputStream;
  
  public class CopyFile
  {
      public static void main(String[] args)
      {
  
          InputStream inStream = null;
          OutputStream outStream = null;
  
          try
          {
  
              File afile = new File("input.txt");
              File bfile = new File("inputCopy.txt");
  
              inStream = new FileInputStream(afile);
              outStream = new FileOutputStream(bfile);
  
              byte[] buffer = new byte[1024];
  
              int length;
              // copy the file content in bytes
              while ((length = inStream.read(buffer)) &gt; 0)
              {
  
                  outStream.write(buffer, 0, length);
  
              }
  
              inStream.close();
              outStream.close();
  
              System.out.println("File is copied successful!");
  
          }
          catch (IOException e)
          {
              e.printStackTrace();
          }
      }
  }
  </code></pre>
  
  <p>I'm not sure how to execute the program - any help? Is this possible on Windows? Why is it different than another environment (I thought JVM was write once, run anywhere)?</p>