Use synchronized, wait() and notify() to write a program such that below mentioned conditions are fulfilled while reading and writing data to a shared resource.

1. When a write is happening, no read or other write should be allowed(read and write threads should wait)

2. When a read is happening, no write should be allowed (write threads should wait) but. other read threads should be able to read.

Donot use any API classes e.g. ReadWriteLock, AtomicInteger etc..