Add Jspecify Feature in starter

starter-core/src/main/java/io/micronaut/starter/feature/other/Jspecify.java

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+/*
+ * Copyright 2017-2025 original authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package io.micronaut.starter.feature.other;
+
+import io.micronaut.context.annotation.Requires;
+import io.micronaut.starter.application.ApplicationType;
+import io.micronaut.starter.application.generator.GeneratorContext;
+import io.micronaut.starter.build.dependencies.Dependency;
+import io.micronaut.starter.feature.Feature;
+import jakarta.annotation.Nullable;
+import jakarta.inject.Singleton;
+
+import static io.micronaut.core.util.StringUtils.TRUE;
+import static io.micronaut.starter.feature.Category.VALIDATION;
+
+@Requires(property = "micronaut.starter.feature.jspecify.enabled", value = TRUE, defaultValue = TRUE)
+@Singleton
+public class Jspecify implements Feature {
+
+    public static final String NAME = "jspecify";
+    private static final Dependency JSPECIFY_DEPENDENCY =
+            Dependency.builder()
+                    .groupId("org.jspecify")
+                    .artifactId("jspecify")
+                    .compile()
+                    .build();
+
+    @Override
+    public String getName() {
+        return NAME;
+    }
+
+    @Override
+    public String getTitle() {
+        return "JSpecify Nullability Annotations";
+    }
+
+    @Override
+    public String getDescription() {
+        return "It adds the JSpecify Nullability Annotations dependency.";
+    }
+
+    @Nullable
+    @Override
+    public String getMicronautDocumentation() {
+        return "https://docs.micronaut.io/latest/guide/#jspecify";
+    }
+
+    @Nullable
+    @Override
+    public String getThirdPartyDocumentation() {
+        return "https://jspecify.dev/docs/start-here/";
+    }
+
+    @Override
+    public boolean supports(ApplicationType applicationType) {
+        return true;
+    }
+
+    @Override
+    public String getCategory() {
+        return VALIDATION;
+    }
+
+    @Override
+    public void apply(GeneratorContext generatorContext) {
+        generatorContext.addDependency(JSPECIFY_DEPENDENCY);
+    }
+}

starter-core/src/test/groovy/io/micronaut/starter/feature/other/JspecifySpec.groovy

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+package io.micronaut.starter.feature.other
+
+import io.micronaut.starter.ApplicationContextSpec
+import io.micronaut.starter.BuildBuilder
+import io.micronaut.starter.application.ApplicationType
+import io.micronaut.starter.build.BuildTestVerifier
+import io.micronaut.starter.fixture.CommandOutputFixture
+import io.micronaut.starter.build.BuildTestUtil
+import io.micronaut.starter.options.BuildTool
+import spock.lang.Shared
+import spock.lang.Subject
+
+class JspecifySpec extends ApplicationContextSpec implements CommandOutputFixture{
+
+    @Shared
+    @Subject
+    Jspecify jspecify = beanContext.getBean(Jspecify)
+
+    void "jspecify supports application type #appType"(ApplicationType appType) {
+        expect:
+        jspecify.supports(appType)
+
+        where:
+        appType << ApplicationType.values()
+    }
+
+    void "jspecify dependencies  #buildTool"(BuildTool buildTool) {
+        when:
+        String template = new BuildBuilder(beanContext, buildTool)
+                .features(['jspecify'])
+                .render()
+        BuildTestVerifier verifier = BuildTestUtil.verifier(buildTool, template)
+
+        then:
+        verifier.hasDependency("jspecify")
+
+        where:
+        buildTool << BuildTool.values()
+    }
+
+    void 'test README.md with feature jspecify contains links to docs'() {
+        when:
+        def output = generate(['jspecify'])
+        def readme = output["README.md"]
+
+        then:
+        readme
+        readme.contains("https://docs.micronaut.io/latest/guide/#jspecify")
+        readme.contains("https://jspecify.dev/docs/start-here/")
+    }
+
+}