I want use @Nullable
annotation to eliminate NullPointerExceptions
. I found some tutorials on the net, I noticed that this annotation comes from the package javax.annotation.Nullable
; but when I import it a compilation error is generated: cannot find symbol
You need to include a jar that this class exists in. You can find it here
If using Maven, you can add the following dependency declaration:
<dependency>
<groupId>com.google.code.findbugs</groupId>
<artifactId>jsr305</artifactId>
<version>3.0.2</version>
</dependency>
and for Gradle:
dependencies {
testImplementation 'com.google.code.findbugs:jsr305:3.0.2'
}
The artifact has been moved from net.sourceforge.findbugs
to
<dependency>
<groupId>com.google.code.findbugs</groupId>
<artifactId>jsr305</artifactId>
<version>3.0.0</version>
</dependency>
If you are using Gradle, you could include the dependency like this:
repositories {
mavenCentral()
}
dependencies {
compile group: 'com.google.code.findbugs', name: 'jsr305', version: '3.0.0'
}
'java'
(or other) plugin that has already created the compile
configuration.
<dependency> <groupId>com.google.code.findbugs</groupId> <artifactId>jsr305</artifactId> <version>3.0.0</version> </dependency>
Eclipse gave errors: Missing artifact com.google.code.findbugs:jsr305:jar:3.0.0 Failure to transfer com.google.code.findbugs:jsr305:jar:3.0.0
compileOnly group...
instead of just compile group...
JSR-305 is a "Java Specification Request" to extend the specification. @Nullable
etc. were part of it; however it appears to be "dormant" (or frozen) ever since (See this SO question). So to use these annotations, you have to add the library yourself.
FindBugs was renamed to SpotBugs and is being developed under that name.
For maven this is the current annotation-only dependency (other integrations here):
<dependency>
<groupId>com.github.spotbugs</groupId>
<artifactId>spotbugs-annotations</artifactId>
<version>4.2.0</version>
</dependency>
If you wish to use the full plugin, refer to the documentation of SpotBugs.
In case someone has this while trying to compile an Android project, there is an alternative Nullable implementation in android.support.annotation.Nullable
. So take care which package you've referenced in your import
s.
If anyone has this issue when building a Maven project created in IntelliJ IDEA externally, I used the following dependency instead of the answer:
<dependency>
<groupId>org.jetbrains</groupId>
<artifactId>annotations</artifactId>
<version>15.0</version>
</dependency>
Using this will allow the project to build on IntelliJ IDEA and by itself using Maven.
You can find it here.
org.jetbrains:annotations:15.0
provides @org.jetbrains.annotations.Nullable
not @javax.annotation.Generated
. This could be a problem in case you use some code generators as openapi-generator-maven-plugin
.
you can add latest version of this by adding following line inside your gradle.build.
implementation group: 'com.google.code.findbugs', name: 'jsr305', version: '3.0.2'
I am using Guava which has annotation included:
(Gradle code )
compile 'com.google.guava:guava:23.4-jre'
com.google.code.findbugs:jsr305
is named poorly, but it is the official reference implementation.
In the case of Android projects, you can fix this error by changing the project/module gradle file (build.gradle) as follows:
dependencies { implementation 'com.android.support:support-annotations:24.2.0' }
For more informations, please refer here.
For gradle build I used compile('com.google.code.findbugs:jsr305:3.0.2')
. In case of test can use testCompile('com.google.code.findbugs:jsr305:3.0.2')
.
Success story sharing
javax
package? Isn't there an artifact with ajavax
-prefixed groupId that provides this type?com.google.code.findbugs
because it was being hosted on Google's code hosting solution