If generated public and private key pairs using RSA algorithm, and after that I want to encrypt some data with the public key. How I can achieve it. I need an example program to encrypt data using rsa public key. Is it necessary to use rsa algorithm in encyption, when we used rsa algorithm to created public and private keys. Please give me the answer with an example.

The Java API for encryption is called JCE; a code sample can be found here. This one in particular uses DES, not RSA, but by reading the relevant javadocs you should be able to adapt it easily.