CodeConventions.pdf

Java

Code Conventions

September 12, 1997

2550 Garcia Avenue, Mountain View, California 94043-1100 U.S.A.

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pending applications.

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Company, Ltd.

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All other product names mentioned herein are the trademarks of their respective owners.

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IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY,

FITNESS FOR A PARTICULAR PURPOSE, OR NON-INFRINGEMENT.

THIS DOCUMENT COULD INCLUDE TECHNICAL INACCURACIES OR TYPOGRAPHICAL ERRORS.

CHANGES ARE PERIODICALLY ADDED TO THE INFORMATION HEREIN; THESE CHANGES WILL BE

INCORPORATED IN NEW EDITIONS OF THE DOCUMENT. SUN MICROSYSTEMS, INC. MAY MAKE

IMPROVEMENTS AND/OR CHANGES IN THE PRODUCT(S) AND/OR THE PROGRAM(S) DESCRIBED IN THIS

DOCUMENT AT ANY TIME.

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Recycle

June 2, 1997

1 Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

1.1

Why Have Code Conventions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

2 File Names . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

2.1

File Sufﬁxes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

3 File Organization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

3.1

Java Source Files . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

3.1.1

Beginning Comments. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

3.1.2

Package and Import Statements . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

3.1.3

Class and Interface Declarations . . . . . . . . . . . . . . . . . . . . . . . . . . 3

4 Indentation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

4.1

Line Length . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

5 Comments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

5.1

Implementation Comment Formats . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

5.1.1

Block Comments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

5.1.2

Single-Line Comments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

5.1.3

Trailing Comments. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

5.1.4

End-Of-Line Comments. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

5.2

Documentation Comments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

6 Declarations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

6.1

Number Per Line . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

6.2

Placement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9

6.3

Initialization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

6.4

Class and Interface Declarations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

7 Statements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

7.1

Simple Statements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

7.2

Compound Statements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

7.3

return Statements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

7.4

if, if-else, if-else-if-else Statements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

7.5

for Statements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

7.6

while Statements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

7.7

do-while Statements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

7.8

switch Statements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

7.9

try-catch Statements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

8 White Space . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

8.1

Blank Lines. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

9 Naming Conventions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

10 Programming Practices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

10.1 Providing Access to Instance and Class Variables . . . . . . . . . . . . . . . . . . . 15

iii

1.2

Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1

2.2

Common File Names . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

4.2

Wrapping Lines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

8.2

Blank Spaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

June 2, 1997

10.2 Referring to Class Variables and Methods . . . . . . . . . . . . . . . . . . . . . . . . . 16

10.3 Constants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

10.4 Variable Assignments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

10.5 Miscellaneous Practices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

10.5.1 Parentheses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

10.5.2 Returning Values . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

10.5.3 Expressions before ‘?’ in the Conditional Operator. . . . . . . . . . . 17

10.5.4 Special Comments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

11 Code Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

11.1 Java Source File Example. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18

2 - File Names

Java Code Conventions

1 - Introduction

1.1 Why Have Code Conventions

Code conventions are important to programmers for a number of reasons:

• 80% of the lifetime cost of a piece of software goes to maintenance.

• Hardly any software is maintained for its whole life by the original author.

• Code conventions improve the readability of the software, allowing engineers to

understand new code more quickly and thoroughly.

• If you ship your source code as a product, you need to make sure it is as well packaged

and clean as any other product you create.

1.2 Acknowledgments

This document reﬂects the Java language coding standards presented in the Java Language

Speciﬁcation , from Sun Microsystems. Major contributions are from Peter King, Patrick

Naughton, Mike DeMoney, Jonni Kanerva, Kathy Walrath, and Scott Hommel.

For questions concerning adaptation, modiﬁcation, or redistribution of this document, please

read our copyright notice at http://java.sun.com/docs/codeconv/html/Copyright.doc.html.

Comments on this document should be submitted to our feedback form at http://java.sun.com/

docs/forms/sendusmail.html.

2 - File Names

This section lists commonly used ﬁle sufﬁxes and names.

Plik z chomika:

Inne pliki z tego folderu:

Inne foldery tego chomika: