Big Java, 4th Edition

Appendix E. Java Syntax Summary

In this syntax summary, we use a monospaced font for actual Java reserved words and tokens such as while. An italic font denotes language constructs such as condition or variable. Items enclosed in brackets [ ] are optional. Items separated by vertical bars | are alternatives. Do not include the brackets or vertical bars in your code!

The summary reflects the parts of the Java language that were covered in this book. For a full overview of the Java syntax, see http://java.sun.com/docs/books/jls/.

As always, please be careful to distinguish an ellipsis ... from the ... token. The latter appears twice in this appendix in the "variable parameters" discussion in the "Methods" section.

Types

A type is a primitive type or a reference type. The primitive types are

• The numeric types int, long, short, char, byte, float, double

• The boolean type

The reference types are

• Classes such as String or Employee

• Enumeration types such as enum Sex { FEMALE, MALE }

• Interfaces such as Comparable

• Array types such as Employee[] or int[][]

Variables

Local variable declarations have the form

[final] Type variableName [= initializer];

Examples:

double x = 0;
String harry = "Harry Handsome";
Rectangle box = new Rectangle(5, 10, 20, 30);
int[] a = { 1, 4, 9, 16, 25 };

The variable name consists only of letters, numbers, and underscores. It must begin with a letter or underscore. Names are case-sensitive: totalscore, TOTALSCORE, and totalScore are three different variables.

The scope of a local ...