Java注释规范

Java注释规范
2007年03月27日 星期二 14:01

Java
代码规范

--
注释

@author LEI

@version 1.10 2005-09-01

1
注释文档的格式

注释文档将用来生成
HTML
格式的代码报告，所以注释文档必须书写在类、域、构造函数、方法、定义之前。注释文档由两部分组成——描述、块标记。

例如：


/**


* The doGet method of the servlet.


* This method is called when a form has its tag value method equals to get.


*


* @param request


*
the request send by the client to the server


* @param response


*
the response send by the server to the client


* @throws ServletException


*
if an error occurred


* @throws IOException


*
if an error occurred


*/


public void doGet (HttpServletRequest request, HttpServletResponse response)


throws ServletException, IOException {




doPost(request, response);

}

前两行为描述，描述完毕后，由
@
符号起头为块标记注视。

2

注释的种类

2.1
文件头注释

文件头注释以
/*
开始，以
*/
结束，需要注明该文件创建时间，文件名，命名空间信息。

例如：

/*

* Created on 2005-7-2


* /

2.2
类、接口注释

类、接口的注释采用
/** … */
，描述部分用来书写该类的作用或者相关信息，块标记部分必须注明作者和版本。

例如：

/**
Title: XXXX DRIVER 3.0

*
Description: XXXX DRIVER 3.0

*
Copyright: Copyright (c) 2003

*
Company:XXXX有限公司

*

* @author Java Development Group

* @version 3.0

*/

例如：

/**

* A class representing a window on the screen.

* For example:

*

*
Window win = new Window(parent);

*
win.show();

*

*

* @author
Sami Shaio

* @version %I%, %G%

* @see
java.awt.BaseWindow

* @see
java.awt.Button

*/

class Window extends BaseWindow {


...

}

2.3
构造函数注释

构造函数注释采用
/** … */
，描述部分注明构造函数的作用，不一定有块标记部分。

例如：

/**

*
默认构造函数

*/

有例如：


/**

*
带参数构造函数
,
初始化模式名
,
名称和数据源类型


*


* @param schema


*
Ref
模式名


* @param name


*
Ref
名称


* @param type


*
byVal
数据源类型


*/

2.4
域注释

域注释可以出现在注释文档里面，也可以不出现在注释文档里面。用
/** … */
的域注释将会被认为是注释文档热出现在最终生成的
HTML
报告里面，而使用
/* … */
的注释会被忽略。

例如：

/*
由于
triger
和表用一个
DMSource
，所以要区分和表的迁移成功标记
*/

boolean isTrigerSuccess = false;

又例如：

/**
由于
triger
和表用一个
DMSource
，所以要区分和表的迁移成功标记
*/

boolean isTrigerSuccess = false;

再例如：

/**

* The X-coordinate of the component.

*


* @see #getLocation()


*/


int x = 1263732;

2.5
方法注释

方法注释采用
/** … */
，描述部分注明方法的功能，块标记部分注明方法的参数，返回值，异常等信息。例如：

/**

*
设置是否有外码约束

*

* @param conn

*
Connection
与数据库的连接

*/

2.6
定义注释

规则同域注释。

3
注释块标记

3.1
标记的顺序

块标记将采用如下顺序：

…

*

* @param
(classes, interfaces, methods and constructors only)

* @return
(methods only)

* @exception
(@throws is a synonym added in Javadoc 1.2)

* @author
(classes and interfaces only, required)

* @version
(classes and interfaces only, required. See footnote 1)

* @see

* @since

* @serial
(or @serialField or @serialData)

* @deprecated
(see How and When To Deprecate APIs)

* …

一个块标记可以根据需要重复出现多次，多次出现的标记按照如下顺序：

@author
按照时间先后顺序（
chronological
）

@param
按照参数定义顺序（
declaration
）

@throws
按照异常名字的字母顺序（
alphabetically
）

@see
按照如下顺序：

@see #field

@see #Constructor(Type, Type...)

@see #Constructor(Type id, Type id...)

@see #method(Type, Type,...)

@see #method(Type id, Type, id...)

@see Class

@see Class#field

@see Class#Constructor(Type, Type...)

@see Class#Constructor(Type id, Type id)

@see Class#method(Type, Type,...)

@see Class#method(Type id, Type id,...)

@see package.Class

@see package.Class#field

@see package.Class#Constructor(Type, Type...)

@see package.Class#Constructor(Type id, Type id)

@see package.Class#method(Type, Type,...)

@see package.Class#method(Type id, Type, id)

@see package

3.2
标记介绍

3.2.1 @param
标记

@param
后面空格后跟着参数的变量名字（不是类型），空格后跟着对该参数的描述。

在描述中第一个名字为该变量的数据类型，表示数据类型的名次前面可以有一个冠词如：
a,an,the
。如果是
int
类型的参数则不需要注明数据类型。例如：

…


* @param ch
the char
用用来……


* @param _image
the image
用来……


* @param _num

一个数字……

…

对于参数的描述如果只是一短语，最好不要首字母大写，结尾也不要句号。

对于参数的描述是一个句子，最好不要首字母大写，如果出现了句号这说明你的描述不止一句话。如果非要首字母大写的话，必须用句号来结束句子。（英文的句号）

公司内部添加
ByRef
和
ByVal
两个标记，例如：

* @param _image the image ByRef
用来……

说明该参数是引用传递（指针），
ByVal
可以省略，表示是值传递。

3.2.2 @return
标记

返回为空（
void
）的构造函数或者函数，
@return
可以省略。

如果返回值就是输入参数，必须用与输入参数的
@param
相同的描述信息。

必要的时候注明特殊条件写的返回值。

3.2.3 @throws
标记

@throws
以前使用的是
@exception
。

@throws
的内容必须在函数的
throws
部分定义。

3.2.4 @author
标记

类注释标记。

函数注释里面可以不出现
@author
。

3.2.5 @version

类注释标记。

函数注释里面可以不出现
@version

3.2.6 @since

类注释标记。

标明该类可以运行的
JDK
版本

例如：

@since JDK1.2

3.2.7 @deprecated

由于某种原因而被宣布将要被废弃的方法。

/**


* @deprecated
As of JDK 1.1, replaced by


*
setBounds


* @see #setBounds(int,int,int,int)


*/

3.2.8 @link
标记

语法：
{@link
package.class#member
label}

Label
为链接文字。

package.class#member
将被自动转换成指向
package.class
的
member
文件的
URL
。

4 HTML
代码的使用

在注释描述部分可以使用
HTML
代码。

…

表示段落

….

表示自动标号

5
注释示例

/**


* Graphics is the abstract base class for all graphics contexts


* which allow an application to draw onto components realized on


* various devices or onto off-screen images.


* A Graphics object encapsulates the state information needed


* for the various rendering operations that Java supports.
This


* state information includes:


*


*
The Component to draw on


*
A translation origin for rendering and clipping coordinates


*
The current clip


*
The current color


*
The current font


*
The current logical pixel operation function (XOR or Paint)


*
The current XOR alternation color


*
(see setXORMode
)


*


*


* Coordinates are infinitely thin and lie between the pixels of the


* output device.


* Operations which draw the outline of a figure operate by traversing


* along the infinitely thin path with a pixel-sized pen that hangs


* down and to the right of the anchor point on the path.


* Operations which fill a figure operate by filling the interior


* of the infinitely thin path.


* Operations which render horizontal text render the ascending


* portion of the characters entirely above the baseline coordinate.


*


* Some important points to consider are that drawing a figure that


* covers a given rectangle will occupy one extra row of pixels on


* the right and bottom edges compared to filling a figure that is


* bounded by that same rectangle.


* Also, drawing a horizontal line along the same y coordinate as


* the baseline of a line of text will draw the line entirely below


* the text except for any descenders.


* Both of these properties are due to the pen hanging down and to


* the right from the path that it traverses.


*


* All coordinates which appear as arguments to the methods of this


* Graphics object are considered relative to the translation origin


* of this Graphics object prior to the invocation of the method.


* All rendering operations modify only pixels which lie within the


* area bounded by both the current clip of the graphics context


* and the extents of the Component used to create the Graphics object.


*


* @author
Sami Shaio


* @author
Arthur van Hoff


* @version
%I%, %G%


* @since
1.0


*/

public abstract class Graphics {




/**


* Draws as much of the specified image as is currently available


* with its northwest corner at the specified coordinate (x, y).


* This method will return immediately in all cases, even if the


* entire image has not yet been scaled, dithered and converted


* for the current output device.


*


* If the current output representation is not yet complete then


* the method will return false and the indicated


* {@link ImageObserver} object will be notified as the


* conversion process progresses.


*


* @param img
the image to be drawn


* @param x
the x-coordinate of the northwest corner


*
of the destination rectangle in pixels


* @param y
the y-coordinate of the northwest corner


*
of the destination rectangle in pixels


* @param observer
the image observer to be notified as more


*
of the image is converted.
May be


*

null

* @return

true

if the image is completely


*
loaded and was painted successfully;


*

false

otherwise.


* @see
Image


* @see
ImageObserver


* @since
1.0


*/


public abstract boolean drawImage(Image img, int x, int y,


ImageObserver observer);






/**


* Dispose of the system resources used by this graphics context.


* The Graphics context cannot be used after being disposed of.


* While the finalization process of the garbage collector will


* also dispose of the same system resources, due to the number


* of Graphics objects that can be created in short time frames


* it is preferable to manually free the associated resources


* using this method rather than to rely on a finalization


* process which may not happen for a long period of time.


*


* Graphics objects which are provided as arguments to the paint


* and update methods of Components are automatically disposed


* by the system when those methods return.
Programmers should,


* for efficiency, call the dispose method when finished using


* a Graphics object only if it was created directly from a


* Component or another Graphics object.


*


* @see
#create(int, int, int, int)


* @see
#finalize()


* @see
Component#getGraphics()


* @see
Component#paint(Graphics)


* @see
Component#update(Graphics)


* @since
1.0


*/


public abstract void dispose();




/**


* Disposes of this graphics context once it is no longer


* referenced.


*


* @see
#dispose()


* @since
1.0


*/


public void finalize() {

dispose();


}

}