Write a java program that will read a positive integer from the user and will print out the $3$N$+1$ sequence starting from that integer. The program should also count and print out the number of terms in the sequence.

Given a positive integer, N$,$ define the $3$N$+1$ sequence starting from N as follows: If N is an even number, then divide N by two; but if N is odd, then multiply N by $3$ and add $1.$ Continue to generate numbers in this way until N becomes equal to $1.$

You must validate the starting number must be positive.