The AIA file is in itself is the source code of the application.
If you are asking how to convert the AIA to Java code directly, then I am afraid that it is not possible as of now.
I assume here that you are trying to include blocks as an image but they turn out to be too small to be legible in an image.
You can try including some important portions of the blocks instead of the entire blocks area.
If they are vertically long, try to factor them into smaller procedures and including them separately instead of trying to include the entire block as such.