Ensures that exceptions (defined as any class name conforming - * to some regular expression) are immutable. That is, have only final - * fields.
+ *Ensures that exceptions (classes with names conforming to some regular + * expression and explicitly extending classes with names conforming to other + * regular expression) are immutable. That is, they have only final fields.
* Rationale: Exception instances should represent an error
* condition. Having non final fields not only allows the state to be
* modified by accident and therefore mask the original condition but
@@ -38,8 +38,10 @@ import com.puppycrawl.tools.checkstyle.checks.AbstractFormatCheck;
*/
public final class MutableExceptionCheck extends AbstractFormatCheck
{
- /** Default value for format property. */
- private static final String DEFAULT_FORMAT = "^.*Exception$|^.*Error$";
+ /** Default value for format and extendedClassNameFormat properties. */
+ private static final String DEFAULT_FORMAT = "^.*Exception$|^.*Error$|^.*Throwable$";
+ /** Pattern for class name that is being extended */
+ private String mExtendedClassNameFormat;
/** Stack of checking information for classes. */
private final FastStack
- Ensures that exception classes (classes with names conforming to
- some regular expression) are immutable, that is, that they have only final
- fields.
+ Ensures that exception classes (classes with names conforming to some regular
+ expression and explicitly extending classes with names conforming to other
+ regular expression) are immutable, that is, that they have only final fields.
@@ -348,7 +348,13 @@ public class StringUtils // not final to allow subclassing
String value
+ */
+ public void setExtendedClassNameFormat(String aExtendedClassNameFormat)
+ {
+ mExtendedClassNameFormat = aExtendedClassNameFormat;
}
@Override
@@ -97,19 +109,18 @@ public final class MutableExceptionCheck extends AbstractFormatCheck
private void visitClassDef(DetailAST aAST)
{
mCheckingStack.push(mChecking ? Boolean.TRUE : Boolean.FALSE);
- mChecking =
- isExceptionClass(aAST.findFirstToken(TokenTypes.IDENT).getText());
+ mChecking = isNamedAsException(aAST) && isExtendedClassNamedAsException(aAST);
}
/** Called when we leave class definition. */
private void leaveClassDef()
{
- mChecking = (mCheckingStack.pop()).booleanValue();
+ mChecking = mCheckingStack.pop();
}
/**
* Checks variable definition.
- * @param aAST variable def node for check.
+ * @param aAST variable def node for check
*/
private void visitVariableDef(DetailAST aAST)
{
@@ -117,7 +128,7 @@ public final class MutableExceptionCheck extends AbstractFormatCheck
final DetailAST modifiersAST =
aAST.findFirstToken(TokenTypes.MODIFIERS);
- if (!(modifiersAST.findFirstToken(TokenTypes.FINAL) != null)) {
+ if (modifiersAST.findFirstToken(TokenTypes.FINAL) == null) {
log(aAST.getLineNo(), aAST.getColumnNo(), "mutable.exception",
aAST.findFirstToken(TokenTypes.IDENT).getText());
}
@@ -125,11 +136,29 @@ public final class MutableExceptionCheck extends AbstractFormatCheck
}
/**
- * @param aClassName class name to check
- * @return true if a given class name confirms specified format
+ * @param aAST class definition node
+ * @return true if a class name conforms to specified format
*/
- private boolean isExceptionClass(String aClassName)
+ private boolean isNamedAsException(DetailAST aAST)
{
- return getRegexp().matcher(aClassName).find();
+ final String className = aAST.findFirstToken(TokenTypes.IDENT).getText();
+ return getRegexp().matcher(className).find();
+ }
+
+ /**
+ * @param aAST class definition node
+ * @return true if extended class name conforms to specified format
+ */
+ private boolean isExtendedClassNamedAsException(DetailAST aAST)
+ {
+ final DetailAST extendsClause = aAST.findFirstToken(TokenTypes.EXTENDS_CLAUSE);
+ if (extendsClause != null) {
+ final DetailAST extendedClass = extendsClause.findFirstToken(TokenTypes.IDENT);
+ if (extendedClass != null) {
+ final String extendedClassName = extendedClass.getText();
+ return extendedClassName.matches(mExtendedClassNameFormat);
+ }
+ }
+ return false;
}
}
diff --git a/src/test/java/com/puppycrawl/tools/checkstyle/checks/design/MutableExceptionCheckTest.java b/src/test/java/com/puppycrawl/tools/checkstyle/checks/design/MutableExceptionCheckTest.java
index ef63ded17..451ec40b1 100644
--- a/src/test/java/com/puppycrawl/tools/checkstyle/checks/design/MutableExceptionCheckTest.java
+++ b/src/test/java/com/puppycrawl/tools/checkstyle/checks/design/MutableExceptionCheckTest.java
@@ -20,19 +20,33 @@ package com.puppycrawl.tools.checkstyle.checks.design;
import com.puppycrawl.tools.checkstyle.BaseCheckTestSupport;
import com.puppycrawl.tools.checkstyle.DefaultConfiguration;
-import java.io.File;
import org.junit.Test;
+import java.io.File;
+
public class MutableExceptionCheckTest extends BaseCheckTestSupport
{
@Test
- public void test() throws Exception
+ public void testDefault() throws Exception
{
DefaultConfiguration checkConfig = createCheckConfig(MutableExceptionCheck.class);
String[] expected = {
- "6:9: The field '_errorCode' must be declared final.",
- "23:9: The field '_errorCode' must be declared final.",
+ "6:9: The field 'errorCode' must be declared final.",
+ "23:9: The field 'errorCode' must be declared final.",
+ };
+
+ verify(checkConfig, getPath("design" + File.separator + "InputMutableException.java"), expected);
+ }
+
+ @Test
+ public void testFormat() throws Exception
+ {
+ DefaultConfiguration checkConfig = createCheckConfig(MutableExceptionCheck.class);
+ checkConfig.addAttribute("format", "^.*Failure$");
+ checkConfig.addAttribute("extendedClassNameFormat", "^.*ThreadDeath$");
+ String[] expected = {
+ "34:13: The field 'errorCode' must be declared final.",
};
verify(checkConfig, getPath("design" + File.separator + "InputMutableException.java"), expected);
diff --git a/src/test/resources/com/puppycrawl/tools/checkstyle/design/InputMutableException.java b/src/test/resources/com/puppycrawl/tools/checkstyle/design/InputMutableException.java
index e15eb0f0d..188d2bfc9 100644
--- a/src/test/resources/com/puppycrawl/tools/checkstyle/design/InputMutableException.java
+++ b/src/test/resources/com/puppycrawl/tools/checkstyle/design/InputMutableException.java
@@ -1,25 +1,37 @@
package com.puppycrawl.tools.checkstyle.design;
public class InputMutableException {
- public class FooException {
- private final int _finalErrorCode;
- private int _errorCode = 1;
+ public class FooException extends Exception {
+ private final int finalErrorCode;
+ private int errorCode = 1;
public FooException() {
- _finalErrorCode = 1;
+ finalErrorCode = 1;
}
- public class FooExceptionThisIsNot {
- private final int _finalErrorCode;
- private int _errorCode = 1;
+ public class FooExceptionThisIsNot extends RuntimeException {
+ private final int finalErrorCode;
+ private int errorCode = 1;
/** constructor */
public FooExceptionThisIsNot() {
- _finalErrorCode = 1;
+ finalErrorCode = 1;
}
}
}
- public class FooError {
- private int _errorCode;
+ public class BarError extends Throwable {
+ private int errorCode;
+ }
+
+ public class BazDoesNotExtendError {
+ private int errorCode;
+ }
+
+ public class CustomProblem extends ThreadDeath {
+ private int errorCode;
+
+ public class CustomFailure extends ThreadDeath {
+ private int errorCode;
+ }
}
}
diff --git a/src/xdocs/config_design.xml b/src/xdocs/config_design.xml
index dac5c564c..63b02d3f9 100644
--- a/src/xdocs/config_design.xml
+++ b/src/xdocs/config_design.xml
@@ -313,9 +313,9 @@ public class StringUtils // not final to allow subclassing
format
pattern for exception class names
regular expression
- ^.*Exception$|^.*Error$^.*Exception$|^.*Error$|^.*Throwable$
+
extendedClassNameFormat
+ pattern for extended class names
+ regular expression
+ ^.*Exception$|^.*Error$|^.*Throwable$