Java Coding Standards
The guidelines provided by Java are intended to improve the readability of code and make it consistent across the wide spectrum of Java projects. A style guide is about consistency. Consistency with this style guide is important. Consistency within a project is more important. Consistency within one package, class, or method is the most important.
The main goal of the recommendation is to improve readability and thereby the understanding and the maintainability and general quality of the code. It is impossible to cover all the specific cases in a general guide and the programmer should be flexible.
Now let’s talk about the naming convention in Java:-
1. Package name:-
It should be an in lowercase ASCII letter such as java, lang. If the name contains multiple words, it should be separated by dots (.) such as java.util, java. lang.
Examples: mypackage, com.company.application.ui, com.sun.eng, com.apple.quicktime.v2
2. Class and Interface name:-
It should start with the uppercase letter. It should be a noun such as Color, Button, System, Thread, etc. Use appropriate words, instead of acronyms.
Examples: interface Bicycle, class MountainBike implements Bicycle, interface Sport, class Football implements Sport
3. Method name:-
Usually, the method name should either be a verb or verb-noun combination starting with the lower letter. If it contains multiple words then every inner word should start with uppercase.
Examples: print(), sleep(), setSalary()
4. Variable name:-
i) Instance variable:- Usually variable name should be a noun starting with a lowercase letter. If it contains multiple words then every inner word should start with uppercase.
Examples: name, age. mobileNumber
ii)Constants (final variables):-Usually, a constant name should be a noun. It should contain the only uppercase If it contains multiple words then words are separated with the ( _ ) underscore symbol. Usually, we declare constants with public static and final modifiers.
Examples:- MAX_ITERATIONS, COLOR_RED
iii) boolean variables:- It uses is as a prefix before the variable name.
Example:- isSet, isVisible, isFinished, isFound, isOpen
iv) Private variable:- It uses underscore ( _ ) at end of the variable name.
Example:- private String name_;
5. Java bean:- A Java Bean is a simple java class with private properties and public getter and setter methods
Getter Methods:
- It should be a public method
- Method name should be prefixed with “get”
- It should not take any argument
Setter Methods:
- It should be a public method
- Return Type should be void
- Method name should be prefixed with “set”
- It should take some argument
Above are the most used naming convention. Some of the points regarding coding standards
- Generic variables should have the same name as their type.
Example:-
2. n prefix should be used for variables representing a number of objects.
Example:- nPoints, nLines
3. No suffix should be used for variables representing an entity number.
Example:- tableNo, employeeNo
4. Iterator variables should be called i, j, k, etc.
Example:- for (int i = 0; i < nTables; i++) { }
5. Negated boolean variable names must be avoided.
Example:-
6. Imported classes must always be listed explicitly. Importing classes explicitly gives an excellent documentation value for the class at hand and makes the class easier to comprehend and maintain.
Example:-
7. Method modifiers should be given in the following order:
<access> static abstract synchronized <unusual> final native
The <access> modifier (if present) must be the first modifier.
<access> is one of public, protected or private while <unusual> includes volatile and transient. The most important point here is to keep the access modifier as the first modifier.
Example:-
8. Arrays should be declared with their brackets next to the type.
Example:-
The reason is twofold. First, the array-ness is a feature of the class, not the variable. Second, when returning an array from a method, it is not possible to have the brackets with other than the type (as shown in the last example).
