Configure nullability checks with ErrorProne

See gh-1562

Co-authored-by: Andy Wilkinson <[email protected]>
Co-authored-by: Brian Clozel <[email protected]>

Author: 3 people

gradle/plugins/conventions-plugin/build.gradle

@@ -15,6 +15,7 @@ dependencies {
 	checkstyle("io.spring.javaformat:spring-javaformat-checkstyle:${javaFormatVersion}")
 
 	implementation("com.github.ben-manes:gradle-versions-plugin:$gradleVersionsPluginVersion")
+	implementation("io.spring.gradle.nullability:nullability-plugin:$nullabilityPluginVersion")
 	implementation("io.spring.javaformat:spring-javaformat-gradle-plugin:$javaFormatVersion")
 
 	testImplementation("org.junit.jupiter:junit-jupiter")

gradle/plugins/conventions-plugin/src/main/java/org/springframework/ws/gradle/conventions/ConventionsPlugin.java

@@ -16,6 +16,7 @@
 
 package org.springframework.ws.gradle.conventions;
 
+import io.spring.gradle.nullability.NullabilityPlugin;
 import org.gradle.api.Plugin;
 import org.gradle.api.Project;
 import org.gradle.api.plugins.JavaBasePlugin;
@@ -37,7 +38,10 @@ public void apply(Project project) {
 			new JavaBasePluginConventions().apply(project);
 			new CheckstyleConventions().apply(project);
 		});
-		project.getPlugins().withType(JavaPlugin.class).all((plugin) -> new JavaPluginConventions().apply(project));
+		project.getPlugins().withType(JavaPlugin.class).all((plugin) -> {
+			project.getPlugins().apply(NullabilityPlugin.class);
+			new JavaPluginConventions().apply(project);
+		});
 		project.getPlugins()
 			.withType(MavenPublishPlugin.class)
 			.all((plugin) -> new MavenPublishPluginConventions().apply(project));

gradle/plugins/gradle.properties

@@ -2,3 +2,4 @@ assertJVersion=3.25.3
 gradleVersionsPluginVersion=0.52.0
 javaFormatVersion=0.0.45
 junitVersion=5.11.0
+nullabilityPluginVersion=0.0.1

src/checkstyle/checkstyle-suppressions.xml

@@ -8,4 +8,6 @@
 	<suppress files="." checks="SpringMethodVisibility"/>
 
 	<suppress files=".+TransportConstants\.java" checks="InterfaceIsType"/>
+	<!-- Ignore this check for @Nullable annotations -->
+	<suppress files="[\\/]src[\\/]main[\\/]java[\\/]" checks="AnnotationLocation" />
 </suppressions>