Since Checkstyle 5.0
Verifies that the @Override
annotation is present
when the @inheritDoc
javadoc tag is present.
Rationale: The @Override annotation helps compiler tools ensure that an override is actually occurring. It is quite easy to accidentally overload a method or hide a static method and using the @Override annotation points out these problems.
This check will log a violation if using the @inheritDoc tag on a method that is not valid (ex: private, or static method).
There is a slight difference between the @Override annotation in Java 5 versus Java 6 and above. In Java 5, any method overridden from an interface cannot be annotated with @Override. In Java 6 this behavior is allowed.
As a result of the aforementioned difference between Java 5 and Java 6, a
property called javaFiveCompatibility
is available. This
property will only check classes, interfaces, etc. that do not contain the
extends or implements keyword or are not anonymous classes. This means it
only checks methods overridden from java.lang.Object
.
Java 5 Compatibility mode severely limits this check. It is recommended to
only use it on Java 5 source.
name | description | type | default value | since |
---|---|---|---|---|
javaFiveCompatibility | Enable java 5 compatibility mode. | boolean | false |
5.0 |
To configure the check:
<module name="Checker"> <module name="TreeWalker"> <module name="MissingOverride"/> </module> </module>
Example:
class Example1 extends ParentClass1 { /** {@inheritDoc} */ @Override public void test1() { // OK } /** {@inheritDoc} */ public void test2() { // violation, 'include @java.lang.Override' } /** {@inheritDoc} */ // violation below '{@inheritDoc} tag is not valid at this location.' private void test3() { } /** {@inheritDoc} */ // violation below '{@inheritDoc} tag is not valid at this location.' public static void test4() { } }
To configure the check for the javaFiveCompatibility
mode:
<module name="Checker"> <module name="TreeWalker"> <module name="MissingOverride"> <property name="javaFiveCompatibility" value="true"/> </module> </module> </module>
Example:
class Example2 { /** {@inheritDoc} */ public boolean equals(Object o) { // violation, 'include @java.lang.Override' return o == this; } } interface B { /** {@inheritDoc} */ void test(); // violation, 'include @java.lang.Override' } class C extends ParentClass2 { /** {@inheritDoc} */ public void test() { // OK, is ignored because class extends other class } } class D implements B { /** {@inheritDoc} */ public void test() { // OK, is ignored because class implements interface } } class E { Runnable r = new Runnable() { /** {@inheritDoc} */ public void run() { // OK, is ignored because class is anonymous class } }; }
All messages can be customized if the default message doesn't suit you. Please see the documentation to learn how to.
com.puppycrawl.tools.checkstyle.checks.annotation