It's a CONVENTION, not a rule.
Pero hanggat maari, follow Java naming conventions (kung gusto mong pumasa sa job testing/interview).
1) Class Name = starts with Uppercase letter (halimbawa: String, App, Converter, Sorter, etc.)
2) Method Name = starts with lowercase letter (halimbawa: display(), toString(), calculate(), etc.)
3) Variable Name = starts with lowercase letter (halimbawa: count, firstName, color, age, etc.)
4) Constant Name = should ALL UPPERCASE letters (halimbawa: MAXIMUM_COUNT, RADIUS, BLACK, etc.)
***CamelCase = pag consist of multiple words ang pangalan, gamitan ng "camelCase" or "CamelCase".
...second, third, fourth word always starts with Uppercase.
.....at mga ilan pa pero these are at the top of the list.
Again, hindi ito batas na kailangan sundin.....pero recommended to follow kung gusto mong tanggapin ka sa trabaho. Papansinin yan ng interviewer, bagsak ka kaagad pag kakita pa lang sa sample code mo. Pero kung extra-ordinary naman ang potential mo (kahit wala sa convention), at some point pagsasabihan ka ng mga team members mo or team lead mo)....
Pag nakita niyo na wala sa convention ang iyong professor, pagsabihan nyo para makaganti kayo... lol
Ok, goodluck!
Pero hanggat maari, follow Java naming conventions (kung gusto mong pumasa sa job testing/interview).
1) Class Name = starts with Uppercase letter (halimbawa: String, App, Converter, Sorter, etc.)
2) Method Name = starts with lowercase letter (halimbawa: display(), toString(), calculate(), etc.)
3) Variable Name = starts with lowercase letter (halimbawa: count, firstName, color, age, etc.)
4) Constant Name = should ALL UPPERCASE letters (halimbawa: MAXIMUM_COUNT, RADIUS, BLACK, etc.)
***CamelCase = pag consist of multiple words ang pangalan, gamitan ng "camelCase" or "CamelCase".
...second, third, fourth word always starts with Uppercase.
.....at mga ilan pa pero these are at the top of the list.
Again, hindi ito batas na kailangan sundin.....pero recommended to follow kung gusto mong tanggapin ka sa trabaho. Papansinin yan ng interviewer, bagsak ka kaagad pag kakita pa lang sa sample code mo. Pero kung extra-ordinary naman ang potential mo (kahit wala sa convention), at some point pagsasabihan ka ng mga team members mo or team lead mo)....
Pag nakita niyo na wala sa convention ang iyong professor, pagsabihan nyo para makaganti kayo... lol

Ok, goodluck!