com.puppycrawl.tools.checkstyle.checks.coding

Class IllegalThrowsCheck

java.lang.Object

com.puppycrawl.tools.checkstyle.api.AutomaticBean

com.puppycrawl.tools.checkstyle.api.AbstractViolationReporter

com.puppycrawl.tools.checkstyle.api.AbstractCheck

com.puppycrawl.tools.checkstyle.checks.coding.IllegalThrowsCheck

All Implemented Interfaces:

Configurable, Contextualizable

public final class IllegalThrowsCheck
extends AbstractCheck

Checks that specified types are not declared to be thrown. Declaring that a method throws java.lang.Error or java.lang.RuntimeException is almost never acceptable.

• Property illegalClassNames - Specify throw class names to reject. Type is java.lang.String[]. Default value is Error, RuntimeException, Throwable, java.lang.Error, java.lang.RuntimeException, java.lang.Throwable.
• Property ignoredMethodNames - Specify names of methods to ignore. Type is java.lang.String[]. Default value is finalize.
• Property ignoreOverriddenMethods - allow to ignore checking overridden methods (marked with Override or java.lang.Override annotation). Type is boolean. Default value is true.

To configure the check:

 <module name="IllegalThrows"/>
 

Example:

 public class Test {
   public void func1() throws RuntimeException {} // violation
   public void func2() throws Exception {}  // ok
   public void func3() throws Error {}  // violation
   public void func4() throws Throwable {} // violation
   public void func5() throws NullPointerException {} // ok
   @Override
   public void toString() throws Error {} // ok
 }
 

To configure the check rejecting throws NullPointerException from methods:

 <module name="IllegalThrows">
   <property name="illegalClassNames" value="NullPointerException"/>
 </module>
 

Example:

 public class Test {
   public void func1() throws RuntimeException {} // ok
   public void func2() throws Exception {}  // ok
   public void func3() throws Error {}  // ok
   public void func4() throws Throwable {} // ok
   public void func5() throws NullPointerException {} // violation
   @Override
   public void toString() throws Error {} // ok
 }
 

To configure the check ignoring method named "func1()":

 <module name="IllegalThrows">
   <property name="ignoredMethodNames" value="func1"/>
 </module>
 

Example:

 public class Test {
   public void func1() throws RuntimeException {} // ok
   public void func2() throws Exception {}  // ok
   public void func3() throws Error {}  // violation
   public void func4() throws Throwable {} // violation
   public void func5() throws NullPointerException {} // ok
   @Override
   public void toString() throws Error {} // ok
 }
 

To configure the check to warn on overridden methods:

 <module name="IllegalThrows">
   <property name="ignoreOverriddenMethods" value="false"/>
 </module>
 

Example:

 public class Test {
   public void func1() throws RuntimeException {} // violation
   public void func2() throws Exception {}  // ok
   public void func3() throws Error {}  // violation
   public void func4() throws Throwable {} // violation
   public void func5() throws NullPointerException {} // ok
   @Override
   public void toString() throws Error {} // violation
 }
 

Parent is com.puppycrawl.tools.checkstyle.TreeWalker

Violation Message Keys:

• illegal.throw

Since:

4.0

Nested Class Summary

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

AutomaticBean.OutputStreamOptions

Field Summary

Fields

Modifier and Type	Field and Description
private java.util.Set<java.lang.String>	ignoredMethodNames Specify names of methods to ignore.
private boolean	ignoreOverriddenMethods Allow to ignore checking overridden methods (marked with Override or java.lang.Override annotation).
private java.util.Set<java.lang.String>	illegalClassNames Specify throw class names to reject.
static java.lang.String	MSG_KEY A key is pointing to the warning message text in "messages.properties" file.

Constructor Summary

Constructors

Constructor and Description
IllegalThrowsCheck()

Method Summary

Modifier and Type	Method and Description
int[]	getAcceptableTokens() The configurable token set.
int[]	getDefaultTokens() Returns the default token a check is interested in.
int[]	getRequiredTokens() The tokens that this check must be registered for.
private boolean	isIgnorableMethod(DetailAST methodDef) Checks if current method is ignorable due to Check's properties.
void	setIgnoredMethodNames(java.lang.String... methodNames) Setter to specify names of methods to ignore.
void	setIgnoreOverriddenMethods(boolean ignoreOverriddenMethods) Setter to allow to ignore checking overridden methods (marked with Override or java.lang.Override annotation).
void	setIllegalClassNames(java.lang.String... classNames) Setter to specify throw class names to reject.
private boolean	shouldIgnoreMethod(java.lang.String name) Check if the method is specified in the ignore method list.
void	visitToken(DetailAST detailAST) Called to process a token.

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

beginTree, clearViolations, destroy, finishTree, getFileContents, getLine, getLineCodePoints, getLines, getTabWidth, getTokenNames, getViolations, 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 java.lang.String MSG_KEY

A key is pointing to the warning message text in "messages.properties" file.

See Also:

Constant Field Values

ignoredMethodNames

private final java.util.Set<java.lang.String> ignoredMethodNames

Specify names of methods to ignore.

illegalClassNames

private final java.util.Set<java.lang.String> illegalClassNames

Specify throw class names to reject.

ignoreOverriddenMethods

private boolean ignoreOverriddenMethods

Allow to ignore checking overridden methods (marked with Override or java.lang.Override annotation).

Constructor Detail

IllegalThrowsCheck

public IllegalThrowsCheck()

Method Detail

setIllegalClassNames

public void setIllegalClassNames(java.lang.String... classNames)

Setter to specify throw class names to reject.

Parameters:

classNames - array of illegal exception classes

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 class AbstractCheck

Returns:

the default tokens

See Also:

TokenTypes

getRequiredTokens

public int[] getRequiredTokens()

Description copied from class: AbstractCheck

The tokens that this check must be registered for.

Specified by:

getRequiredTokens in class AbstractCheck

Returns:

the token set this must be registered for.

See Also:

TokenTypes

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 class AbstractCheck

Returns:

the token set this check is designed for.

See Also:

TokenTypes

visitToken

public void visitToken(DetailAST detailAST)

Description copied from class: AbstractCheck

Called to process a token.

Overrides:

visitToken in class AbstractCheck

Parameters:

detailAST - the token to process

isIgnorableMethod

private boolean isIgnorableMethod(DetailAST methodDef)

Checks if current method is ignorable due to Check's properties.

Parameters:

methodDef - METHOD_DEF

Returns:

true if method is ignorable.

shouldIgnoreMethod

private boolean shouldIgnoreMethod(java.lang.String name)

Check if the method is specified in the ignore method list.

Parameters:

name - the name to check

Returns:

whether the method with the passed name should be ignored

setIgnoredMethodNames

public void setIgnoredMethodNames(java.lang.String... methodNames)

Setter to specify names of methods to ignore.

Parameters:

methodNames - array of ignored method names

setIgnoreOverriddenMethods

public void setIgnoreOverriddenMethods(boolean ignoreOverriddenMethods)

Setter to allow to ignore checking overridden methods (marked with Override or java.lang.Override annotation).

Parameters:

ignoreOverriddenMethods - Check's property.