Keywords: current

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## 1.1.4 Capitalization and Commenting Conventions

By convention, Java programs are written entirely in lower case characters with three exceptions.

- The first letter of class names are capitalized to distinguish class names from member names.
- The names of constant `static final` fields are written entirely capital letters. For example, the `static final` fields in the preceding subsection are all capitalized according to this convention.
- The first letter in each word of a multi-word identifier after the first is capitalized. For example, the built-in Java class Object includes a method called `toString()` that we will discuss later. The capital `S` signifies the beginning of a word within the multi-word name `toString()`.

These conventions are not enforced by Java compilers, but it is considered bad style to violate them. A related convention is to never use the special character `$` in a name; this character is reserved for the use of the Java compiler. Unfortunately, most Java compilers do not enforce this convention.

Java relies on commenting conventions similar to those in C++. A comment that is confined to a single line begins with the character sequence `//` and ends at the end of the line. Longer comments must be enclosed between the opening ``bracket'' `/*` and ``closing'' bracket `*/`. Examples of both form of comments appear in Section 1.4. Note that a bracketed comment can appear in the middle of a line of code.

Finger Exercise: add both forms of comment to the `Conversions` and `Person` classes from the preceding exercise.

Next: 1.2 Java Data Types Up: 1.1 Introduction Previous: 1.1.3 Defining Constants