Headers

Header

Description

Checks that a source file begins with a specified header. Property headerFile specifies a file that contains the required header. Alternatively, the header specification can be set directly in the header property without the need for an external file.

Property ignoreLines specifies the line numbers to ignore when matching lines in a header file. This property is very useful for supporting headers that contain copyright dates. For example, consider the following header:

line 1: ////////////////////////////////////////////////////////////////////
line 2: // checkstyle:
line 3: // Checks Java source code for adherence to a set of rules.
line 4: // Copyright (C) 2002  Oliver Burn
line 5: ////////////////////////////////////////////////////////////////////

Since the year information will change over time, you can tell Checkstyle to ignore line 4 by setting property ignoreLines to 4.

Properties

name description type default value
headerFile name of the file containing the required header    
header the required header specified inline. Individual header lines must be separated by the string "\n" (even on platforms with a different line separator), see examples below.    
ignoreLines line numbers to ignore    

Example

To configure the check to use header file "java.header" and ignore lines 2, 3, and 4:

<module name="Header">
    <property name="headerFile" value="java.header"/>
    <property name="ignoreLines" value="2, 3, 4"/>
</module>

To configure the check to verify that each file starts with the header

// Copyright (C) 2004 MyCompany
// All rights reserved

without the need for an external header file:

<module name="Header">
    <property name="header"
              value="// Copyright (C) 2004 MyCompany\n// All rights reserved"/>
</module>

Package

com.puppycrawl.tools.checkstyle.checks

Parent Module

TreeWalker

RegexpHeader

Description

Checks the header of a source file against a header that contains a regular expression for each line of the source header.

Rationale: In some projects checking against a fixed header is not sufficient, e.g. the header might require a copyright line where the year information is not static.

For example, consider the following header:

line  1: ^/{71}$
line  2: ^// checkstyle:$
line  3: ^// Checks Java source code for adherence to a set of rules\.$
line  4: ^// Copyright \(C\) \d\d\d\d  Oliver Burn$
line  5: ^// Last modification by \$Author.*\$$
line  6: ^/{71}$
line  7:
line  8: ^package
line  9:
line 10: ^import
line 11:
line 12: ^/\*\*
line 13: ^ \*([^/]|$)
line 14: ^ \*/

Lines 1 and 6 demonstrate a more compact notation for 71 '/' characters. Line 4 enforces that the copyright notice includes a four digit year. Line 5 is an example how to enforce revision control keywords in a file header. Lines 12-14 is a template for javadoc (line 13 is so complicated to remove conflict with and of javadoc comment).

Properties

name description type default value
headerFile name of the file containing the required header    
header the required header specified inline. Individual header lines must be separated by the string "\n" (even on platforms with a different line separator), and regular expressions must not span multiple lines.    
multiLines line numbers to repeat (zero or more times)    

Example

To configure the check to use header file "java.header" and 10 and 13 muli-lines:

<module name="RegexpHeader">
    <property name="headerFile" value="java.header"/>
    <property name="multiLines" value="10, 13"/>
</module>

To configure the check to verify that each file starts with the header

^// Copyright \(C\) (\d\d\d\d -)? 2004 MyCompany$
^// All rights reserved$

without the need for an external header file:

<module name="RegexpHeader">
  <property
    name="header"
    value="^// Copyright \(C\) (\d\d\d\d -)? 2004 MyCompany$\n^// All rights reserved$"/>
</module>

Note: ignoreLines property has been removed from this check to simplify it. To make some line optional use "^.*$" regexp for this line.

Package

com.puppycrawl.tools.checkstyle.checks

Parent Module

TreeWalker

Copyright © 2001-2005, Oliver Burn