Read a file from inside of an external Jar file?

Question

I'm trying to read a file from inside an external jar using java.. For example, I have two jar files. One is "foo.jar" the other is "bar.jar". Inside of "bar.jar" is the file "foo-bar.txt". How do i read the file "foo-bar.txt" from inside of "bar.jar" using code in "foo.jar"...? Is this even possible..? I know that i can read a file from iside of foo.jar using

this.getClass().getClassLoader().getResourceAsStream("foo-bar.txt");

But I don't know how to do it from an external jar.. can someone help me?

Answer 1

Use jar url to open connection the example code

InputStream in = null;
String inputFile = "jar:file:/c:/path/to/my.jar!/myfile.txt";
if (inputFile.startsWith("jar:")){
  try {
    inputURL = new URL(inputFile);
    JarURLConnection conn = (JarURLConnection)inputURL.openConnection();
    in = conn.getInputStream();
  } catch (MalformedURLException e1) {
    System.err.println("Malformed input URL: "+inputURL);
    return;
  } catch (IOException e1) {
    System.err.println("IO error open connection");
    return;
  }
}