Class AvoidEscapedUnicodeCharactersCheck
- All Implemented Interfaces:
Configurable
,Contextualizable
Restricts using Unicode escapes (such as \u221e). It is possible to allow using escapes for non-printable, control characters. Also, this check can be configured to allow using escapes if trail comment is present. By the option it is possible to allow using escapes if literal contains only them.
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Property
allowEscapesForControlCharacters
- Allow use escapes for non-printable, control characters. Type isboolean
. Default value isfalse
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Property
allowByTailComment
- Allow use escapes if trail comment is present. Type isboolean
. Default value isfalse
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Property
allowIfAllCharactersEscaped
- Allow if all characters in literal are escaped. Type isboolean
. Default value isfalse
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Property
allowNonPrintableEscapes
- Allow use escapes for non-printable, whitespace characters. Type isboolean
. Default value isfalse
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To configure the check:
<module name="AvoidEscapedUnicodeCharacters"/>
Examples of using Unicode:
String unitAbbrev = "μs"; // Best: perfectly clear even without a comment. String unitAbbrev = "\u03bcs"; // Poor: the reader has no idea what this is.
An example of non-printable, control characters.
return '\ufeff' + content; // byte order mark
An example of how to configure the check to allow using escapes for non-printable, control characters:
<module name="AvoidEscapedUnicodeCharacters"> <property name="allowEscapesForControlCharacters" value="true"/> </module>
Example of using escapes with trail comment:
String unitAbbrev = "\u03bcs"; // Greek letter mu, "s" String textBlockUnitAbbrev = """ \u03bcs"""; // Greek letter mu, "s"
An example of how to configure the check to allow using escapes if trail comment is present:
<module name="AvoidEscapedUnicodeCharacters"> <property name="allowByTailComment" value="true"/> </module>
Example of using escapes if literal contains only them:
String unitAbbrev = "\u03bc\u03bc\u03bc";
An example of how to configure the check to allow escapes if literal contains only them:
<module name="AvoidEscapedUnicodeCharacters"> <property name="allowIfAllCharactersEscaped" value="true"/> </module>
An example of how to configure the check to allow using escapes for non-printable, whitespace characters:
<module name="AvoidEscapedUnicodeCharacters"> <property name="allowNonPrintableEscapes" value="true"/> </module>
Parent is com.puppycrawl.tools.checkstyle.TreeWalker
Violation Message Keys:
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forbid.escaped.unicode.char
- Since:
- 5.8
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Nested Class Summary
Nested classes/interfaces inherited from class com.puppycrawl.tools.checkstyle.api.AutomaticBean
AutomaticBean.OutputStreamOptions
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Field Summary
Fields -
Constructor Summary
Constructors -
Method Summary
Modifier and TypeMethodDescriptionvoid
Called before the starting to process a tree.int[]
The configurable token set.int[]
Returns the default token a check is interested in.int[]
The tokens that this check must be registered for.final void
setAllowByTailComment
(boolean allow) Setter to allow use escapes if trail comment is present.final void
setAllowEscapesForControlCharacters
(boolean allow) Setter to allow use escapes for non-printable, control characters.final void
setAllowIfAllCharactersEscaped
(boolean allow) Setter to allow if all characters in literal are escaped.final void
setAllowNonPrintableEscapes
(boolean allow) Setter to allow use escapes for non-printable, whitespace characters.void
visitToken
(DetailAST ast) Called to process a token.Methods inherited from class com.puppycrawl.tools.checkstyle.api.AbstractCheck
clearMessages, destroy, finishTree, getFileContents, getLine, getLines, getMessages, getTabWidth, getTokenNames, init, isCommentNodesRequired, leaveToken, log, log, log, setFileContents, setTabWidth, setTokens
Methods inherited from class com.puppycrawl.tools.checkstyle.api.AbstractViolationReporter
finishLocalSetup, getCustomMessages, getId, getMessageBundle, getSeverity, getSeverityLevel, setId, setSeverity
Methods inherited from class com.puppycrawl.tools.checkstyle.api.AutomaticBean
configure, contextualize, getConfiguration, setupChild
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Field Details
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MSG_KEY
A key is pointing to the warning message text in "messages.properties" file.- See Also:
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Constructor Details
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AvoidEscapedUnicodeCharactersCheck
public AvoidEscapedUnicodeCharactersCheck()
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Method Details
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setAllowEscapesForControlCharacters
public final void setAllowEscapesForControlCharacters(boolean allow) Setter to allow use escapes for non-printable, control characters.- Parameters:
allow
- user's value.
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setAllowByTailComment
public final void setAllowByTailComment(boolean allow) Setter to allow use escapes if trail comment is present.- Parameters:
allow
- user's value.
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setAllowIfAllCharactersEscaped
public final void setAllowIfAllCharactersEscaped(boolean allow) Setter to allow if all characters in literal are escaped.- Parameters:
allow
- user's value.
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setAllowNonPrintableEscapes
public final void setAllowNonPrintableEscapes(boolean allow) Setter to allow use escapes for non-printable, whitespace characters.- Parameters:
allow
- user's value.
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getDefaultTokens
public int[] getDefaultTokens()Description copied from class:AbstractCheck
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 classAbstractCheck
- Returns:
- the default tokens
- See Also:
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getAcceptableTokens
public int[] getAcceptableTokens()Description copied from class:AbstractCheck
The configurable token set. Used to protect Checks against malicious users who specify an unacceptable token set in the configuration file. The default implementation returns the check's default tokens.- Specified by:
getAcceptableTokens
in classAbstractCheck
- Returns:
- the token set this check is designed for.
- See Also:
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getRequiredTokens
public int[] getRequiredTokens()Description copied from class:AbstractCheck
The tokens that this check must be registered for.- Specified by:
getRequiredTokens
in classAbstractCheck
- Returns:
- the token set this must be registered for.
- See Also:
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beginTree
Description copied from class:AbstractCheck
Called before the starting to process a tree. Ideal place to initialize information that is to be collected whilst processing a tree.- Overrides:
beginTree
in classAbstractCheck
- Parameters:
rootAST
- the root of the tree
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visitToken
Description copied from class:AbstractCheck
Called to process a token.- Overrides:
visitToken
in classAbstractCheck
- Parameters:
ast
- the token to process
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