I am wondering is there a way to get scanned image with text to be converted to readable text by writing code for it? Is that possible?
OCRTools is what I use for .net
For Java, i've used Aspire in the past, it's very good, a little scary though. I've heard a lot about tesseract, you might as well check that out.
If you are getting confused by the answer: What you are looking for is an Optical Character Recognition software's API/SDK. What you've asked in the question points to building an OCR from scratch. That requires understanding Image Processing (mainly object recognition).