com.github.sevntu.checkstyle.checks.coding

Class EitherLogOrThrowCheck

java.lang.Object

com.puppycrawl.tools.checkstyle.api.AutomaticBean

com.puppycrawl.tools.checkstyle.api.AbstractViolationReporter

com.puppycrawl.tools.checkstyle.api.AbstractCheck

com.github.sevntu.checkstyle.checks.coding.EitherLogOrThrowCheck

All Implemented Interfaces:

com.puppycrawl.tools.checkstyle.api.Configurable, com.puppycrawl.tools.checkstyle.api.Contextualizable

public class EitherLogOrThrowCheck
extends com.puppycrawl.tools.checkstyle.api.AbstractCheck

Either log the exception, or throw it, but never do both. Logging and throwing results in multiple log messages for a single problem in the code, and makes problems for the support engineer who is trying to dig through the logs. This is one of the most annoying error-handling antipatterns. All of these examples are equally wrong.

Examples:

 catch (NoSuchMethodException e) {
     LOG.error("Message", e);
     throw e;
 }
 

or

 catch (NoSuchMethodException e) {
     LOG.error("Message", e);
     throw new MyServiceException("AnotherMessage", e);
 }
 

or

 catch (NoSuchMethodException e) {
      e.printStackTrace();
      throw new MyServiceException("Message", e);
 }
 

What check can detect:
Loggers

• logger is declared as class field
• logger is declared as method's local variable
• logger is declared as local variable in catch block
• logger is passed through method's parameters

Exceptions

• logger logs catch parameter exception or its message
• throw catch parameter exception
• throw another exception which is based on catch parameter exception
• printStackTrace was called on catch parameter exception

What check can not detect:

• loggers that is used like method's return value. Example:

   getLogger().error("message", e)
   

• loggers that is used like static fields from another classes:

   MyAnotherClass.LOGGER.error("message", e);
   

Default parameters are:

• loggerFullyQualifiedClassName - fully qualified class name of logger type. Default value is "org.slf4j.Logger".
• loggingMethodNames - comma separated names of logging methods. Default value is "error, warn, info, debug".

Note that check works with only one logger type. If you have multiple different loggers, then create another instance of this check.

Since:

1.9.0

Author:

Baratali Izmailov

Nested Class Summary

Nested classes/interfaces inherited from class com.puppycrawl.tools.checkstyle.api.AutomaticBean

com.puppycrawl.tools.checkstyle.api.AutomaticBean.OutputStreamOptions

Field Summary

Fields

Modifier and Type	Field and Description
static String	MSG_KEY Key for error message.

Constructor Summary

Constructors

Constructor and Description
EitherLogOrThrowCheck()

Method Summary

Modifier and Type	Method and Description
int[]	getAcceptableTokens()
int[]	getDefaultTokens()
int[]	getRequiredTokens()
void	setLoggerFullyQualifiedClassName(String loggerFullyQualifiedClassName) Set logger full class name and logger simple class name.
void	setLoggingMethodNames(String... loggingMethodNames) Set logging method names.
void	visitToken(com.puppycrawl.tools.checkstyle.api.DetailAST ast)

Methods inherited from class com.puppycrawl.tools.checkstyle.api.AbstractCheck

beginTree, 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

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

MSG_KEY

public static final String MSG_KEY

Key for error message.

See Also:

Constant Field Values

Constructor Detail

EitherLogOrThrowCheck

public EitherLogOrThrowCheck()

Method Detail

setLoggerFullyQualifiedClassName

public void setLoggerFullyQualifiedClassName(String loggerFullyQualifiedClassName)

Set logger full class name and logger simple class name.

Parameters:

loggerFullyQualifiedClassName - Logger full class name. Example: org.slf4j.Logger.

setLoggingMethodNames

public void setLoggingMethodNames(String... loggingMethodNames)

Set logging method names.

Parameters:

loggingMethodNames - Logger method names.

getDefaultTokens

public int[] getDefaultTokens()

Specified by:

getDefaultTokens in class com.puppycrawl.tools.checkstyle.api.AbstractCheck

getAcceptableTokens

public int[] getAcceptableTokens()

Specified by:

getAcceptableTokens in class com.puppycrawl.tools.checkstyle.api.AbstractCheck

getRequiredTokens

public int[] getRequiredTokens()

Specified by:

getRequiredTokens in class com.puppycrawl.tools.checkstyle.api.AbstractCheck

visitToken

public void visitToken(com.puppycrawl.tools.checkstyle.api.DetailAST ast)

Overrides:

visitToken in class com.puppycrawl.tools.checkstyle.api.AbstractCheck