Merge pull request #1584 from zambrovski

* pr/1584:
  Polish "Add ability to exclude ProjectGenerationConfiguration"
  Add ability to exclude ProjectGenerationConfiguration

Closes gh-1584

initializr-generator/src/main/java/io/spring/initializr/generator/project/ProjectGenerationConfigurationTypeFilter.java

@@ -0,0 +1,80 @@
+/*
+ * Copyright 2012-2024 the original author or 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.spring.initializr.generator.project;
+
+import java.util.Arrays;
+import java.util.Set;
+import java.util.function.Predicate;
+
+/**
+ * Allows to filter {@link ProjectGenerationConfiguration}.
+ *
+ * @author Simon Zambrovski
+ * @author Moritz Halbritter
+ */
+public interface ProjectGenerationConfigurationTypeFilter extends Predicate<Class<?>> {
+
+	/**
+	 * Creates a {@link ProjectGenerationConfigurationTypeFilter} which includes the given
+	 * types.
+	 * @param types the types to include
+	 * @return a {@link ProjectGenerationConfigurationTypeFilter}
+	 */
+	static ProjectGenerationConfigurationTypeFilter include(Class<?>... types) {
+		Set<Class<?>> classes = Set.of(types);
+		return classes::contains;
+	}
+
+	/**
+	 * Creates a {@link ProjectGenerationConfigurationTypeFilter} which excludes the given
+	 * types.
+	 * @param types the types to exclude
+	 * @return a {@link ProjectGenerationConfigurationTypeFilter}
+	 */
+	static ProjectGenerationConfigurationTypeFilter exclude(Class<?>... types) {
+		Set<Class<?>> classes = Set.of(types);
+		return (clazz) -> !classes.contains(clazz);
+	}
+
+	/**
+	 * Creates a {@link ProjectGenerationConfigurationTypeFilter} from multiple filters
+	 * which must all match.
+	 * @param filters the filters
+	 * @return a combined {@link ProjectGenerationConfigurationTypeFilter}
+	 */
+	static ProjectGenerationConfigurationTypeFilter allMatch(ProjectGenerationConfigurationTypeFilter... filters) {
+		return allMatch(Arrays.asList(filters));
+	}
+
+	/**
+	 * Creates a {@link ProjectGenerationConfigurationTypeFilter} from multiple filters
+	 * which must all match.
+	 * @param filters the filters
+	 * @return a combined {@link ProjectGenerationConfigurationTypeFilter}
+	 */
+	static ProjectGenerationConfigurationTypeFilter allMatch(
+			Iterable<? extends ProjectGenerationConfigurationTypeFilter> filters) {
+		return (clazz) -> {
+			boolean match = true;
+			for (ProjectGenerationConfigurationTypeFilter filter : filters) {
+				match &= filter.test(clazz);
+			}
+			return match;
+		};
+	}
+
+}

initializr-generator/src/main/java/io/spring/initializr/generator/project/ProjectGenerator.java

@@ -24,6 +24,7 @@
 import org.springframework.beans.factory.support.GenericBeanDefinition;
 import org.springframework.context.support.GenericApplicationContext;
 import org.springframework.core.io.support.SpringFactoriesLoader;
+import org.springframework.util.ClassUtils;
 
 /**
  * Main entry point for project generation that processes a {@link ProjectDescription} by
@@ -34,6 +35,8 @@
  *
  * @author Andy Wilkinson
  * @author Stephane Nicoll
+ * @author Simon Zambrovski
+ * @author Moritz Halbritter
  */
 public class ProjectGenerator {
 
@@ -116,17 +119,45 @@ public <T> T generate(ProjectDescription description, ProjectAssetGenerator<T> p
 
 	/**
 	 * Return the {@link ProjectGenerationConfiguration} class names that should be
-	 * considered. By default this method will load candidates using
-	 * {@link SpringFactoriesLoader} with {@link ProjectGenerationConfiguration}.
+	 * considered. By default, this method will load candidates using
+	 * {@link SpringFactoriesLoader} with {@link ProjectGenerationConfiguration} and
+	 * exclude those which are not matched by the
+	 * {@link ProjectGenerationConfigurationTypeFilter}, also loaded by
+	 * {@link SpringFactoriesLoader}.
 	 * @param description the description of the project to generate
 	 * @return a list of candidate configurations
 	 */
-	@SuppressWarnings("deprecation")
+
 	protected List<String> getCandidateProjectGenerationConfigurations(ProjectDescription description) {
+		List<String> candidates = getProjectGenerationConfigurationFactoryNames();
+		ProjectGenerationConfigurationTypeFilter filter = getProjectGenerationConfigurationExclusionFilter();
+		return candidates.stream().filter((candidate) -> {
+			Class<?> type = resolveClass(candidate);
+			return type != null && filter.test(type);
+		}).toList();
+	}
+
+	private Class<?> resolveClass(String candidate) {
+		try {
+			return ClassUtils.forName(candidate, getClass().getClassLoader());
+		}
+		catch (ClassNotFoundException ex) {
+			return null;
+		}
+	}
+
+	@SuppressWarnings("deprecation")
+	List<String> getProjectGenerationConfigurationFactoryNames() {
 		return SpringFactoriesLoader.loadFactoryNames(ProjectGenerationConfiguration.class,
 				getClass().getClassLoader());
 	}
 
+	ProjectGenerationConfigurationTypeFilter getProjectGenerationConfigurationExclusionFilter() {
+		List<ProjectGenerationConfigurationTypeFilter> filters = SpringFactoriesLoader
+			.loadFactories(ProjectGenerationConfigurationTypeFilter.class, getClass().getClassLoader());
+		return ProjectGenerationConfigurationTypeFilter.allMatch(filters);
+	}
+
 	private void registerProjectDescription(ProjectGenerationContext context, ProjectDescription description) {
 		context.registerBean(ProjectDescription.class, resolve(description, context));
 	}

initializr-generator/src/test/java/io/spring/initializr/generator/project/ProjectGenerationConfigurationTypeFilterTests.java

@@ -0,0 +1,69 @@
+/*
+ * Copyright 2012-2024 the original author or 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.spring.initializr.generator.project;
+
+import org.junit.jupiter.api.Test;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+/**
+ * Tests for {@link ProjectGenerationConfigurationTypeFilter}.
+ *
+ * @author Moritz Halbritter
+ */
+class ProjectGenerationConfigurationTypeFilterTests {
+
+	@Test
+	void include() {
+		ProjectGenerationConfigurationTypeFilter filter = ProjectGenerationConfigurationTypeFilter.include(A.class,
+				B.class);
+		assertThat(filter).accepts(A.class, B.class);
+		assertThat(filter).rejects(C.class);
+	}
+
+	@Test
+	void exclude() {
+		ProjectGenerationConfigurationTypeFilter filter = ProjectGenerationConfigurationTypeFilter.exclude(A.class,
+				B.class);
+		assertThat(filter).rejects(A.class, B.class);
+		assertThat(filter).accepts(C.class);
+	}
+
+	@Test
+	void allMatch() {
+		ProjectGenerationConfigurationTypeFilter filterA = (clazz) -> clazz.equals(A.class);
+		ProjectGenerationConfigurationTypeFilter filterAorB = (clazz) -> clazz.equals(A.class) || clazz.equals(B.class);
+		ProjectGenerationConfigurationTypeFilter filterNotC = (clazz) -> !clazz.equals(C.class);
+		ProjectGenerationConfigurationTypeFilter combined = ProjectGenerationConfigurationTypeFilter.allMatch(filterA,
+				filterAorB, filterNotC);
+		assertThat(combined).accepts(A.class);
+		assertThat(combined).rejects(B.class, C.class);
+	}
+
+	private static final class A {
+
+	}
+
+	private static final class B {
+
+	}
+
+	private static final class C {
+
+	}
+
+}

initializr-generator/src/test/java/io/spring/initializr/generator/project/ProjectGeneratorTests.java

@@ -25,6 +25,8 @@
 
 import io.spring.initializr.generator.buildsystem.maven.MavenBuildSystem;
 import io.spring.initializr.generator.project.contributor.TestProjectGenerationConfiguration;
+import io.spring.initializr.generator.project.contributor.TestProjectGenerationConfiguration2;
+import org.assertj.core.util.Lists;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.io.TempDir;
 import org.mockito.InOrder;
@@ -181,8 +183,9 @@ void generateCanBeExtendedToFilterProjectContributors(@TempDir Path projectDir)
 		given(description.getBuildSystem()).willReturn(new MavenBuildSystem());
 		ProjectGenerator generator = new ProjectGenerator(mockContextInitializr()) {
 			@Override
-			protected List<String> getCandidateProjectGenerationConfigurations(ProjectDescription description) {
-				assertThat(description).isSameAs(description);
+			protected List<String> getCandidateProjectGenerationConfigurations(
+					ProjectDescription generatorDescription) {
+				assertThat(description).isSameAs(generatorDescription);
 				return Collections.singletonList(TestProjectGenerationConfiguration.class.getName());
 			}
 		};
@@ -195,6 +198,37 @@ protected List<String> getCandidateProjectGenerationConfigurations(ProjectDescri
 		verify(description).getBuildSystem();
 	}
 
+	@Test
+	void loadAndConstructProjectGenerationTypeExclusionFilter() {
+		ProjectGenerator generator = new ProjectGenerator(mockContextInitializr());
+		ProjectGenerationConfigurationTypeFilter filter = generator.getProjectGenerationConfigurationExclusionFilter();
+		assertThat(filter).isNotNull();
+		assertThat(filter.test(TestProjectGenerationConfiguration.class)).isFalse();
+		assertThat(filter.test(TestProjectGenerationConfiguration2.class)).isFalse();
+		assertThat(filter.test(Integer.class)).isTrue();
+	}
+
+	@Test
+	void filterProjectContributorsCorrectly() {
+		ProjectDescription description = mock(ProjectDescription.class);
+		given(description.getArtifactId()).willReturn("test-custom-contributor");
+		given(description.getBuildSystem()).willReturn(new MavenBuildSystem());
+		ProjectGenerator generator = new ProjectGenerator(mockContextInitializr()) {
+			@Override
+			List<String> getProjectGenerationConfigurationFactoryNames() {
+				return Lists.list(TestProjectGenerationConfiguration.class.getName(),
+						TestProjectGenerationConfiguration2.class.getName());
+			}
+
+			@Override
+			ProjectGenerationConfigurationTypeFilter getProjectGenerationConfigurationExclusionFilter() {
+				return (clazz) -> !TestProjectGenerationConfiguration2.class.equals(clazz);
+			}
+		};
+		List<String> candidates = generator.getCandidateProjectGenerationConfigurations(description);
+		assertThat(candidates).containsOnly(TestProjectGenerationConfiguration.class.getCanonicalName());
+	}
+
 	@SuppressWarnings("unchecked")
 	private Consumer<ProjectGenerationContext> mockContextInitializr() {
 		return mock(Consumer.class);

initializr-generator/src/test/java/io/spring/initializr/generator/project/contributor/TestProjectGenerationConfiguration2.java

@@ -0,0 +1,27 @@
+/*
+ * Copyright 2012-2020 the original author or 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.spring.initializr.generator.project.contributor;
+
+import io.spring.initializr.generator.project.ProjectGenerationConfiguration;
+
+/**
+ * Test contributor.
+ */
+@ProjectGenerationConfiguration
+public class TestProjectGenerationConfiguration2 {
+
+}

initializr-generator/src/test/java/io/spring/initializr/generator/project/contributor/TestProjectGenerationConfiguration2ExcludingTypeFilter.java

@@ -0,0 +1,32 @@
+/*
+ * Copyright 2012-2020 the original author or 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.spring.initializr.generator.project.contributor;
+
+import io.spring.initializr.generator.project.ProjectGenerationConfigurationTypeFilter;
+
+public class TestProjectGenerationConfiguration2ExcludingTypeFilter
+		implements ProjectGenerationConfigurationTypeFilter {
+
+	private final ProjectGenerationConfigurationTypeFilter delegate = ProjectGenerationConfigurationTypeFilter
+		.exclude(TestProjectGenerationConfiguration2.class);
+
+	@Override
+	public boolean test(Class<?> type) {
+		return this.delegate.test(type);
+	}
+
+}

initializr-generator/src/test/java/io/spring/initializr/generator/project/contributor/TestProjectGenerationConfigurationExcludingTypeFilter.java

@@ -0,0 +1,31 @@
+/*
+ * Copyright 2012-2020 the original author or 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.spring.initializr.generator.project.contributor;
+
+import io.spring.initializr.generator.project.ProjectGenerationConfigurationTypeFilter;
+
+public class TestProjectGenerationConfigurationExcludingTypeFilter implements ProjectGenerationConfigurationTypeFilter {
+
+	private final ProjectGenerationConfigurationTypeFilter delegate = ProjectGenerationConfigurationTypeFilter
+		.exclude(TestProjectGenerationConfiguration.class);
+
+	@Override
+	public boolean test(Class<?> type) {
+		return this.delegate.test(type);
+	}
+
+}

initializr-generator/src/test/resources/META-INF/spring.factories

@@ -0,0 +1,4 @@
+io.spring.initializr.generator.project.ProjectGenerationConfigurationTypeFilter=\
+  io.spring.initializr.generator.project.contributor.TestProjectGenerationConfigurationExcludingTypeFilter,\
+  io.spring.initializr.generator.project.contributor.TestProjectGenerationConfiguration2ExcludingTypeFilter
+