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javanaming-conventionsoop

Variable naming conventions in Java


In PHP, we (at least the good programmers) always start general variable names with a lower-case letter, but class variables/objects with an uppercase letter to distinguish them. In the same way we start general file names with a lower case letter, but files containing Classes with an upper case letter.

E.g.:

<?php
    $number = 123;
    $string = "a string";
    $colors_array = array('red', 'blue', 'red');
    $Cat = New Cat();
?>

Are the conventions the same in Java, i.e., objects starting with uppercase, but the rest with lowercase, or does everything start with lowercase as I've read in other places?


Solution

  • Generally, all variables will start with lower case:

    int count = 32;
    double conversionFactor = 1.5d;
    

    Some people like to put static constants in all case:

    public static final double KILOGRAM_TO_POUND = 2.20462262;
    

    Things get more annoying when you deal with acronyms, and there is no real standard on whether you should use:

    HTMLHandler myHtmlHandler; 
    

    or

    HTMLHandler myHTMLHandler.
    

    Now, either way, note that the class names (Object, String, HTMLHandler) always start with a capital letter, but individual object variables start lowercase.