Question

    public void bar(String fileName) throws IOException{
    FileInputStream fileIn = new FileInputStream(fileName);
    ObjectInputStream in = new ObjectInputStream(fileIn);
    Map map = (HashMap) in.readObject();
}

I’m trying to understand what this piece of code does.

We create a stream, so we’ll be able to read from this file. What does this ObjectInputStream do? Do we read object and make a map out of it? I clearly don’t understand, and I’ll be glad for your help.

Answer 1

My guess is it is reading a HashMap that was previously written to the file using corresponding Out/Write methods.