Is there a way to ignore a single FindBugs warning?

Question

With PMD, if you want to ignore a specific warning, you can use // NOPMD to have that line be ignored.

Is there something similar for FindBugs?

Answer 1

At the time of writing this (May 2018), FindBugs seems to have been replaced by SpotBugs. Using the SuppressFBWarnings annotation requires your code to be compiled with Java 8 or later and introduces a compile time dependency on spotbugs-annotations.jar.

Using a filter file to filter SpotBugs rules has no such issues. The documentation is here.

Answer 2

While other answers on here are valid, they're not a full recipe for solving this.

In the spirit of completeness:

You need to have the findbugs annotations in your pom file - they're only compile time, so you can use the provided scope:

<dependency>
  <groupId>com.google.code.findbugs</groupId>
  <artifactId>findbugs-annotations</artifactId>
  <version>3.0.1</version>
  <scope>provided</scope>
</dependency>

This allows the use of @SuppressFBWarnings there is another dependency which provides @SuppressWarnings. However, the above is clearer.

Then you add the annotation above your method:

E.g.

@SuppressFBWarnings(value = "RCN_REDUNDANT_NULLCHECK_WOULD_HAVE_BEEN_A_NPE",
        justification = "Scanning generated code of try-with-resources")
@Override
public String get() {
    try (InputStream resourceStream =  owningType.getClassLoader().getResourceAsStream(resourcePath);
         BufferedReader reader = new BufferedReader(new InputStreamReader(resourceStream, UTF_8))) { ... }

This includes both the name of the bug and also a reason why you're disabling the scan for it.

Answer 3

The FindBugs initial approach involves XML configuration files aka filters. This is really less convenient than the PMD solution but FindBugs works on bytecode, not on the source code, so comments are obviously not an option. Example:

<Match>
   <Class name="com.mycompany.Foo" />
   <Method name="bar" />
   <Bug pattern="DLS_DEAD_STORE_OF_CLASS_LITERAL" />
</Match>

However, to solve this issue, FindBugs later introduced another solution based on annotations (see SuppressFBWarnings) that you can use at the class or at the method level (more convenient than XML in my opinion). Example (maybe not the best one but, well, it's just an example):

@edu.umd.cs.findbugs.annotations.SuppressFBWarnings(
    value="HE_EQUALS_USE_HASHCODE", 
    justification="I know what I'm doing")

Note that since FindBugs 3.0.0 SuppressWarnings has been deprecated in favor of @SuppressFBWarnings because of the name clash with Java's SuppressWarnings.

Answer 4

Here is a more complete example of an XML filter (the example above by itself will not work since it just shows a snippet and is missing the <FindBugsFilter> begin and end tags):

<FindBugsFilter>
    <Match>
        <Class name="com.mycompany.foo" />
        <Method name="bar" />
        <Bug pattern="NP_BOOLEAN_RETURN_NULL" />
    </Match>
</FindBugsFilter>

If you are using the Android Studio FindBugs plugin, browse to your XML filter file using File->Other Settings->Default Settings->Other Settings->FindBugs-IDEA->Filter->Exclude filter files->Add.

Answer 5

I'm going to leave this one here: https://stackoverflow.com/a/14509697/1356953

Please note that this works with java.lang.SuppressWarningsso no need to use a separate annotation.

@SuppressWarnings on a field only suppresses findbugs warnings reported for that field declaration, not every warning associated with that field.

For example, this suppresses the "Field only ever set to null" warning:

@SuppressWarnings("UWF_NULL_FIELD") String s = null; I think the best you can do is isolate the code with the warning into the smallest method you can, then suppress the warning on the whole method.

Answer 6

As others Mentioned, you can use the @SuppressFBWarnings Annotation. If you don't want or can't add another Dependency to your code, you can add the Annotation to your Code yourself, Findbugs dosn't care in which Package the Annotation is.

@Retention(RetentionPolicy.CLASS)
public @interface SuppressFBWarnings {
    /**
     * The set of FindBugs warnings that are to be suppressed in
     * annotated element. The value can be a bug category, kind or pattern.
     *
     */
    String[] value() default {};

    /**
     * Optional documentation of the reason why the warning is suppressed
     */
    String justification() default "";
}

Source: https://sourceforge.net/p/findbugs/feature-requests/298/#5e88