Java- Cipher Decryption

How can I write a java program that decrypts atext filethat contains several lines of encrypted text with each line having a different shift amount (using casear cipher)? What would the code look like?

Example of Text File-

Bpqa qa i bmab

Pqodkbf ftue fqjf fa dqhqmx ufe yqeemsq

Yv oek qhu lyumydw jxyi oek xqlu ikssuiivkbbo tushofjut jxu cuiiqwu