Class LineLengthCheck

All Implemented Interfaces:
Configurable, Contextualizable

public class LineLengthCheck
extends Check

Checks for long lines.

Rationale: Long lines are hard to read in printouts or if developers have limited screen space for the source code, e.g. if the IDE displays additional information like project tree, class hierarchy, etc.

Note: Support for the special handling of imports in CheckStyle Version 2 has been dropped as it is a special case of regexp: The user can set the ignorePattern to "^import" and achieve the same effect.

The default maximum allowable line length is 80 characters. To change the maximum, set property max.

To ignore lines in the check, set property ignorePattern to a regular expression for the lines to ignore.

An example of how to configure the check is:

 <module name="LineLength"/>

An example of how to configure the check to accept lines up to 120 characters long is:

 <module name="LineLength">
    <property name="max" value="120"/>

An example of how to configure the check to ignore lines that begin with " * ", followed by just one word, such as within a Javadoc comment, is:

 <module name="LineLength">
    <property name="ignorePattern" value="^ *\* *[^ ]+$"/>

Lars Kühne

Constructor Summary
          Creates a new LineLengthCheck instance.
Method Summary
 void beginTree(DetailAST aRootAST)
          Called before the starting to process a tree.
 int[] getDefaultTokens()
          Returns the default token a check is interested in.
 void setIgnorePattern(java.lang.String aFormat)
          Set the ignore pattern.
 void setMax(int aLength)
Methods inherited from class
destroy, finishTree, getAcceptableTokens, getClassLoader, getFileContents, getLines, getRequiredTokens, getTabWidth, getTokenNames, init, leaveToken, log, log, setClassLoader, setFileContents, setMessages, setTabWidth, setTokens, visitToken
Methods inherited from class
getMessageBundle, getSeverity, getSeverityLevel, log, log, log, log, log, log, log, log, log, setSeverity
Methods inherited from class
configure, contextualize, finishLocalSetup, getConfiguration, setupChild
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail


public LineLengthCheck()
Creates a new LineLengthCheck instance.

Method Detail


public int[] getDefaultTokens()
Description copied from class: Check
Returns the default token a check is interested in. Only used if the configuration for a check does not define the tokens.

Specified by:
getDefaultTokens in class Check
the default tokens
See Also:


public void beginTree(DetailAST aRootAST)
Description copied from class: Check
Called before the starting to process a tree. Ideal place to initialise information that is to be collected whilst processing a tree.

beginTree in class Check
aRootAST - the root of the tree
See Also:


public void setMax(int aLength)
aLength - the maximum length of a line


public void setIgnorePattern(java.lang.String aFormat)
                      throws org.apache.commons.beanutils.ConversionException
Set the ignore pattern.

aFormat - a String value
org.apache.commons.beanutils.ConversionException - unable to parse aFormat

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