Question

I have the following method in my client:

  public boolean save() {
    this.ostream.writeObject(Command.SAVE); // write to socket
    return this.istream.readBoolean();
  }

In my server:

    Object o = this.istream.readObject();
    if (o == Command.SAVE) {
      boolean isSaved = save(); // save to database
      this.ostream.writeBoolean(isSaved);
    }

If I use readBoolean and writeBoolean, the readBoolean method in the client blocks, but if I use readObject and writeObject instead, my application works fine. Is there a reason why the readBoolean method would block?

Answer 1

(Its more like comment but code example would be hard to read so I posted it as an answer… Hope it wont bother anyone)

You sure about that? I’ve just tested it by this code

ObjectOutputStream out=new ObjectOutputStream(new FileOutputStream("d:/objects.obj"));
System.out.println("writeObject(true)");
out.writeObject(true);
System.out.println("writeBoolean(true)");
out.writeBoolean(true);
System.out.println("writeBoolean(true)");
out.writeBoolean(true);
out.close();//or flush
System.out.println("------------------");

ObjectInputStream in=new ObjectInputStream(new FileInputStream("d:/objects.obj"));
System.out.println("readObject="+in.readObject());
System.out.println("readBoolean="+in.readBoolean());
System.out.println("readObject="+in.readObject());//<- readObject stored by writeBoolean

and it seams to work fine. Only problems I had was when I tried to readObject stored with writeBoolean or vice versa readBoolean stored with writeObject.

Maybe you just need to flush output stream.