Move build properties to dedicated container

See gh-996

initializr-generator-spring/src/main/java/io/spring/initializr/generator/spring/build/DependencyManagementBuildCustomizer.java

@@ -77,7 +77,7 @@ public class DependencyManagementBuildCustomizer implements BuildCustomizer<Buil
 		resolvedBoms.forEach((key, bom) -> {
 			build.boms().add(key, MetadataBuildItemMapper.toBom(bom));
 			if (bom.getVersionProperty() != null) {
-				build.addVersionProperty(bom.getVersionProperty(), bom.getVersion());
+				build.properties().version(bom.getVersionProperty(), bom.getVersion());
 			}
 		});
 		repositories.keySet().forEach((id) -> build.repositories().add(id));

initializr-generator-spring/src/main/java/io/spring/initializr/generator/spring/build/maven/DefaultMavenBuildCustomizer.java

@@ -20,6 +20,7 @@ import io.spring.initializr.generator.buildsystem.BillOfMaterials;
 import io.spring.initializr.generator.buildsystem.maven.MavenBuild;
 import io.spring.initializr.generator.project.ProjectDescription;
 import io.spring.initializr.generator.spring.build.BuildCustomizer;
+import io.spring.initializr.generator.version.VersionProperty;
 import io.spring.initializr.metadata.InitializrConfiguration.Env.Maven;
 import io.spring.initializr.metadata.InitializrConfiguration.Env.Maven.ParentPom;
 import io.spring.initializr.metadata.InitializrMetadata;
@@ -44,7 +45,7 @@ public class DefaultMavenBuildCustomizer implements BuildCustomizer<MavenBuild>
 	@Override
 	public void customize(MavenBuild build) {
 		build.settings().name(this.description.getName()).description(this.description.getDescription());
-		build.setProperty("java.version", this.description.getLanguage().jvmVersion());
+		build.properties().property("java.version", this.description.getLanguage().jvmVersion());
 		build.plugins().add("org.springframework.boot", "spring-boot-maven-plugin");
 
 		Maven maven = this.metadata.getConfiguration().getEnv().getMaven();
@@ -55,13 +56,13 @@ public class DefaultMavenBuildCustomizer implements BuildCustomizer<MavenBuild>
 			BillOfMaterials springBootBom = MetadataBuildItemMapper
 					.toBom(this.metadata.createSpringBootBom(springBootVersion, versionProperty));
 			if (!hasBom(build, springBootBom)) {
-				build.addInternalVersionProperty(versionProperty, springBootVersion);
+				build.properties().version(VersionProperty.of(versionProperty, true), springBootVersion);
 				build.boms().add("spring-boot", springBootBom);
 			}
 		}
 		if (!maven.isSpringBootStarterParent(parentPom)) {
-			build.setProperty("project.build.sourceEncoding", "UTF-8");
+			build.properties().property("project.build.sourceEncoding", "UTF-8")
-			build.setProperty("project.reporting.outputEncoding", "UTF-8");
+					.property("project.reporting.outputEncoding", "UTF-8");
 		}
 		build.settings().parent(parentPom.getGroupId(), parentPom.getArtifactId(), parentPom.getVersion());
 	}

initializr-generator-spring/src/main/java/io/spring/initializr/generator/spring/code/kotlin/KotlinMavenBuildCustomizer.java

@@ -38,7 +38,7 @@ class KotlinMavenBuildCustomizer implements BuildCustomizer<MavenBuild> {
 
 	@Override
 	public void customize(MavenBuild build) {
-		build.setProperty("kotlin.version", this.settings.getVersion());
+		build.properties().version("kotlin.version", this.settings.getVersion());
 		build.settings().sourceDirectory("${project.basedir}/src/main/kotlin")
 				.testSourceDirectory("${project.basedir}/src/test/kotlin");
 		build.plugins().add("org.jetbrains.kotlin", "kotlin-maven-plugin", (kotlinMavenPlugin) -> {

initializr-generator-spring/src/main/java/io/spring/initializr/generator/spring/code/kotlin/KotlinMavenFullBuildCustomizer.java

@@ -35,7 +35,7 @@ class KotlinMavenFullBuildCustomizer implements BuildCustomizer<MavenBuild> {
 
 	@Override
 	public void customize(MavenBuild build) {
-		build.setProperty("kotlin.version", this.settings.getVersion());
+		build.properties().version("kotlin.version", this.settings.getVersion());
 		build.settings().sourceDirectory("${project.basedir}/src/main/kotlin")
 				.testSourceDirectory("${project.basedir}/src/test/kotlin");
 		build.plugins().add("org.jetbrains.kotlin", "kotlin-maven-plugin", (kotlinMavenPlugin) -> {

initializr-generator-spring/src/test/java/io/spring/initializr/generator/spring/build/BuildComplianceTests.java

@@ -182,11 +182,9 @@ class BuildComplianceTests extends AbstractComplianceTests {
 		ProjectStructure project = generateProject(java, build, "2.1.1.RELEASE",
 				(description) -> description.addDependency("web", MetadataBuildItemMapper.toDependency(WEB)),
 				(projectGenerationContext) -> projectGenerationContext.registerBean(BuildCustomizer.class,
-						() -> (projectBuild) -> {
+						() -> (projectBuild) -> projectBuild.properties()
-							projectBuild.addVersionProperty(VersionProperty.of("spring-foo.version", false),
+								.version(VersionProperty.of("spring-foo.version", false), "0.1.0.RELEASE")
-									"0.1.0.RELEASE");
+								.version(VersionProperty.of("spring-bar.version"), "0.2.0.RELEASE")));
-							projectBuild.addVersionProperty(VersionProperty.of("spring-bar.version"), "0.2.0.RELEASE");
-						}));
 		assertThat(project).textFile(fileName).hasSameContentAs(
 				new ClassPathResource("project/" + build + "/version-override-" + getAssertFileName(fileName)));
 	}

initializr-generator-spring/src/test/java/io/spring/initializr/generator/spring/build/maven/DefaultMavenBuildCustomizerTests.java

@@ -65,7 +65,7 @@ class DefaultMavenBuildCustomizerTests {
 		MutableProjectDescription description = initializeDescription();
 		description.setLanguage(new JavaLanguage("11"));
 		MavenBuild build = customizeBuild(metadata, description);
-		assertThat(build.getProperties()).contains(entry("java.version", "11"));
+		assertThat(build.properties().values()).contains(entry("java.version", "11"));
 	}
 
 	@Test
@@ -90,7 +90,8 @@ class DefaultMavenBuildCustomizerTests {
 		BomContainer boms = build.boms();
 		assertThat(boms.items()).hasSize(1);
 		assertThat(boms.ids()).contains("spring-boot");
-		assertThat(build.getVersionProperties().get(VersionProperty.of("spring-boot.version"))).isEqualTo("2.0.0");
+		assertThat(build.properties().versions(VersionProperty::toStandardFormat))
+				.contains(entry("spring-boot.version", "2.0.0"));
 	}
 
 	@Test

initializr-generator-spring/src/test/java/io/spring/initializr/generator/spring/code/kotlin/KotlinMavenBuildCustomizerTests.java

@@ -23,9 +23,11 @@ import io.spring.initializr.generator.buildsystem.maven.MavenBuild;
 import io.spring.initializr.generator.buildsystem.maven.MavenPlugin.Configuration;
 import io.spring.initializr.generator.buildsystem.maven.MavenPlugin.Dependency;
 import io.spring.initializr.generator.buildsystem.maven.MavenPlugin.Setting;
+import io.spring.initializr.generator.version.VersionProperty;
 import org.junit.jupiter.api.Test;
 
 import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.entry;
 
 /**
  * Tests for {@link KotlinMavenBuildCustomizer}.
@@ -38,8 +40,8 @@ class KotlinMavenBuildCustomizerTests {
 	void kotlinVersionPropertyIsConfigured() {
 		MavenBuild build = new MavenBuild();
 		new KotlinMavenBuildCustomizer(new SimpleKotlinProjectSettings("1.2.70")).customize(build);
-		assertThat(build.getProperties()).hasSize(1);
+		assertThat(build.properties().versions(VersionProperty::toStandardFormat))
-		assertThat(build.getProperties()).containsEntry("kotlin.version", "1.2.70");
+				.containsOnly(entry("kotlin.version", "1.2.70"));
 	}
 
 	@Test

initializr-generator-spring/src/test/java/io/spring/initializr/generator/spring/code/kotlin/KotlinMavenFullBuildCustomizerTests.java

@@ -21,9 +21,11 @@ import io.spring.initializr.generator.buildsystem.maven.MavenPlugin.Configuratio
 import io.spring.initializr.generator.buildsystem.maven.MavenPlugin.Dependency;
 import io.spring.initializr.generator.buildsystem.maven.MavenPlugin.Execution;
 import io.spring.initializr.generator.buildsystem.maven.MavenPlugin.Setting;
+import io.spring.initializr.generator.version.VersionProperty;
 import org.junit.jupiter.api.Test;
 
 import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.entry;
 
 /**
  * Tests for {@link KotlinMavenFullBuildCustomizer}.
@@ -36,8 +38,8 @@ class KotlinMavenFullBuildCustomizerTests {
 	void kotlinVersionPropertyIsConfigured() {
 		MavenBuild build = new MavenBuild();
 		new KotlinMavenFullBuildCustomizer(new SimpleKotlinProjectSettings("1.2.70")).customize(build);
-		assertThat(build.getProperties()).hasSize(1);
+		assertThat(build.properties().versions(VersionProperty::toStandardFormat))
-		assertThat(build.getProperties()).containsEntry("kotlin.version", "1.2.70");
+				.containsOnly(entry("kotlin.version", "1.2.70"));
 	}
 
 	@Test

initializr-generator/src/main/java/io/spring/initializr/generator/buildsystem/Build.java

@@ -16,12 +16,6 @@
 
 package io.spring.initializr.generator.buildsystem;
 
-import java.util.Collections;
-import java.util.Map;
-import java.util.TreeMap;
-
-import io.spring.initializr.generator.version.VersionProperty;
-
 /**
  * Build configuration for a project.
  *
@@ -30,7 +24,7 @@ import io.spring.initializr.generator.version.VersionProperty;
  */
 public abstract class Build {
 
-	private final Map<VersionProperty, String> versionProperties = new TreeMap<>();
+	private final PropertyContainer properties;
 
 	private final DependencyContainer dependencies;
 
@@ -42,6 +36,7 @@ public abstract class Build {
 
 	protected Build(BuildItemResolver buildItemResolver) {
 		BuildItemResolver resolver = determineBuildItemResolver(buildItemResolver);
+		this.properties = new PropertyContainer();
 		this.dependencies = new DependencyContainer(resolver::resolveDependency);
 		this.boms = new BomContainer(resolver::resolveBom);
 		this.repositories = new MavenRepositoryContainer(resolver::resolveRepository);
@@ -68,20 +63,12 @@ public abstract class Build {
 	 */
 	public abstract BuildSettings getSettings();
 
-	public void addVersionProperty(VersionProperty versionProperty, String version) {
+	/**
-		this.versionProperties.put(versionProperty, version);
+	 * Return the {@link PropertyContainer properties container} of this build.
-	}
+	 * @return the properties container of this build.
-
+	 */
-	public void addExternalVersionProperty(String propertyName, String version) {
+	public PropertyContainer properties() {
-		addVersionProperty(VersionProperty.of(propertyName, false), version);
+		return this.properties;
-	}
-
-	public void addInternalVersionProperty(String propertyName, String version) {
-		addVersionProperty(VersionProperty.of(propertyName, true), version);
-	}
-
-	public Map<VersionProperty, String> getVersionProperties() {
-		return Collections.unmodifiableMap(this.versionProperties);
 	}
 
 	public DependencyContainer dependencies() {

initializr-generator/src/main/java/io/spring/initializr/generator/buildsystem/PropertyContainer.java

@@ -0,0 +1,117 @@
+/*
+ * Copyright 2012-2019 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.buildsystem;
+
+import java.util.AbstractMap.SimpleEntry;
+import java.util.Map;
+import java.util.Map.Entry;
+import java.util.TreeMap;
+import java.util.function.Function;
+import java.util.stream.Stream;
+
+import io.spring.initializr.generator.version.VersionProperty;
+
+/**
+ * A container for properties. Arbitrary properties can be specified as well as ones that
+ * refer to a {@link VersionProperty version}.
+ *
+ * @author Stephane Nicoll
+ */
+public class PropertyContainer {
+
+	private final Map<String, String> properties = new TreeMap<>();
+
+	private final Map<VersionProperty, String> versions = new TreeMap<>();
+
+	/**
+	 * Specify if this container is empty.
+	 * @return {@code true} if no property is registered
+	 */
+	public boolean isEmpty() {
+		return this.properties.isEmpty() && this.versions.isEmpty();
+	}
+
+	/**
+	 * Specify if this container has a property with the specified name.
+	 * @param name the name of a property
+	 * @return {@code true} if a property with the specified {@code name} is registered
+	 */
+	public boolean has(String name) {
+		return this.properties.containsKey(name)
+				|| this.versions.keySet().stream().anyMatch((ref) -> ref.toStandardFormat().equals(name));
+	}
+
+	/**
+	 * Register a property with the specified {@code name} and {@code value}. If a
+	 * property with that {@code name} already exists, its value is overridden by the
+	 * specified {@code value}.
+	 * @param name the name of a property
+	 * @param value the value of the property
+	 * @return this container
+	 * @see #version(String, String) to register a property that refers to a version
+	 */
+	public PropertyContainer property(String name, String value) {
+		this.properties.put(name, value);
+		return this;
+	}
+
+	/**
+	 * Register a property that refers to the specified {@link VersionProperty version}.
+	 * If a version with the same {@link VersionProperty} already exists, its value is
+	 * overridden by the specified {@code version}.
+	 * @param versionProperty the name of a version
+	 * @param version the version
+	 * @return this container
+	 */
+	public PropertyContainer version(VersionProperty versionProperty, String version) {
+		this.versions.put(versionProperty, version);
+		return this;
+	}
+
+	/**
+	 * Register a public {@link VersionProperty} with the specified {@code name}. If a
+	 * version with the same {@code name} already exists, its value is overridden by the
+	 * specified {@code version}.
+	 * @param name the public name of a version
+	 * @param version the version
+	 * @return this container
+	 * @see VersionProperty#isInternal()
+	 */
+	public PropertyContainer version(String name, String version) {
+		return version(VersionProperty.of(name, false), version);
+	}
+
+	/**
+	 * Return the registered properties. Does not contain registered versions.
+	 * @return the property entries
+	 */
+	public Stream<Entry<String, String>> values() {
+		return this.properties.entrySet().stream();
+	}
+
+	/**
+	 * Return the registered versions using the specified {@code nameFactory}.
+	 * @param nameFactory the factory to use to generate a version name based on a
+	 * {@link VersionProperty}
+	 * @return the version entries.
+	 */
+	public Stream<Entry<String, String>> versions(Function<VersionProperty, String> nameFactory) {
+		return this.versions.entrySet().stream()
+				.map((entry) -> new SimpleEntry<>(nameFactory.apply(entry.getKey()), entry.getValue()));
+	}
+
+}

initializr-generator/src/main/java/io/spring/initializr/generator/buildsystem/gradle/GradleBuild.java

@@ -25,7 +25,6 @@ import java.util.LinkedHashSet;
 import java.util.List;
 import java.util.Map;
 import java.util.Set;
-import java.util.TreeMap;
 import java.util.function.Consumer;
 
 import io.spring.initializr.generator.buildsystem.Build;
@@ -45,8 +44,6 @@ public class GradleBuild extends Build {
 
 	private final GradleBuildSettings.Builder settings = new Builder();
 
-	private final Map<String, String> ext = new TreeMap<>();
-
 	private final GradlePluginContainer plugins = new GradlePluginContainer();
 
 	private final List<String> configurations = new ArrayList<>();
@@ -79,15 +76,6 @@ public class GradleBuild extends Build {
 		return this.settings.build();
 	}
 
-	public GradleBuild ext(String key, String value) {
-		this.ext.put(key, value);
-		return this;
-	}
-
-	public Map<String, String> getExt() {
-		return Collections.unmodifiableMap(this.ext);
-	}
-
 	public GradlePluginContainer plugins() {
 		return this.plugins;
 	}

initializr-generator/src/main/java/io/spring/initializr/generator/buildsystem/gradle/GradleBuildWriter.java

@@ -24,8 +24,8 @@ import java.util.LinkedHashMap;
 import java.util.LinkedHashSet;
 import java.util.List;
 import java.util.Map;
-import java.util.Map.Entry;
 import java.util.Set;
+import java.util.TreeMap;
 import java.util.function.BiFunction;
 import java.util.function.Function;
 import java.util.function.Predicate;
@@ -37,6 +37,7 @@ import io.spring.initializr.generator.buildsystem.DependencyComparator;
 import io.spring.initializr.generator.buildsystem.DependencyContainer;
 import io.spring.initializr.generator.buildsystem.DependencyScope;
 import io.spring.initializr.generator.buildsystem.MavenRepository;
+import io.spring.initializr.generator.buildsystem.PropertyContainer;
 import io.spring.initializr.generator.buildsystem.gradle.GradleBuild.ConfigurationCustomization;
 import io.spring.initializr.generator.buildsystem.gradle.GradleBuild.TaskCustomization;
 import io.spring.initializr.generator.io.IndentingWriter;
@@ -64,7 +65,7 @@ public abstract class GradleBuildWriter {
 		writer.println();
 		writeConfigurations(writer, build);
 		writeRepositories(writer, build);
-		writeProperties(writer, build);
+		writeProperties(writer, build.properties());
 		writeDependencies(writer, build);
 		writeBoms(writer, build);
 		writeTasksWithTypeCustomizations(writer, build);
@@ -102,20 +103,21 @@ public abstract class GradleBuildWriter {
 
 	protected abstract String repositoryAsString(MavenRepository repository);
 
-	private void writeProperties(IndentingWriter writer, GradleBuild build) {
+	private void writeProperties(IndentingWriter writer, PropertyContainer properties) {
-		if (build.getExt().isEmpty() && build.getVersionProperties().isEmpty()) {
+		if (properties.isEmpty()) {
 			return;
 		}
-		Map<String, String> allProperties = new LinkedHashMap<>(build.getExt());
+		Map<String, String> allProperties = new LinkedHashMap<>(properties.values().collect(Collectors
-		build.getVersionProperties().entrySet()
+				.toMap(Map.Entry::getKey, Map.Entry::getValue, (oldValue, newValue) -> newValue, TreeMap::new)));
-				.forEach((entry) -> allProperties.put(getVersionPropertyKey(entry), "\"" + entry.getValue() + "\""));
+		properties.versions(this::getVersionPropertyKey)
+				.forEach((entry) -> allProperties.put(entry.getKey(), "\"" + entry.getValue() + "\""));
 		writeExtraProperties(writer, allProperties);
 	}
 
 	protected abstract void writeExtraProperties(IndentingWriter writer, Map<String, String> allProperties);
 
-	private String getVersionPropertyKey(Entry<VersionProperty, String> entry) {
+	private String getVersionPropertyKey(VersionProperty versionProperty) {
-		return entry.getKey().isInternal() ? entry.getKey().toCamelCaseFormat() : entry.getKey().toStandardFormat();
+		return versionProperty.isInternal() ? versionProperty.toCamelCaseFormat() : versionProperty.toStandardFormat();
 	}
 
 	private void writeDependencies(IndentingWriter writer, GradleBuild build) {

initializr-generator/src/main/java/io/spring/initializr/generator/buildsystem/maven/MavenBuild.java

@@ -16,10 +16,6 @@
 
 package io.spring.initializr.generator.buildsystem.maven;
 
-import java.util.Collections;
-import java.util.Map;
-import java.util.TreeMap;
-
 import io.spring.initializr.generator.buildsystem.Build;
 import io.spring.initializr.generator.buildsystem.BuildItemResolver;
 import io.spring.initializr.generator.buildsystem.maven.MavenBuildSettings.Builder;
@@ -34,8 +30,6 @@ public class MavenBuild extends Build {
 
 	private final MavenBuildSettings.Builder settings = new Builder();
 
-	private final Map<String, String> properties = new TreeMap<>();
-
 	private final MavenResourceContainer resources = new MavenResourceContainer();
 
 	private final MavenResourceContainer testResources = new MavenResourceContainer();
@@ -60,14 +54,6 @@ public class MavenBuild extends Build {
 		return this.settings.build();
 	}
 
-	public void setProperty(String key, String value) {
-		this.properties.put(key, value);
-	}
-
-	public Map<String, String> getProperties() {
-		return Collections.unmodifiableMap(this.properties);
-	}
-
 	public MavenResourceContainer resources() {
 		return this.resources;
 	}

initializr-generator/src/main/java/io/spring/initializr/generator/buildsystem/maven/MavenBuildWriter.java

@@ -33,10 +33,12 @@ import io.spring.initializr.generator.buildsystem.DependencyComparator;
 import io.spring.initializr.generator.buildsystem.DependencyContainer;
 import io.spring.initializr.generator.buildsystem.DependencyScope;
 import io.spring.initializr.generator.buildsystem.MavenRepository;
+import io.spring.initializr.generator.buildsystem.PropertyContainer;
 import io.spring.initializr.generator.buildsystem.maven.MavenPlugin.Configuration;
 import io.spring.initializr.generator.buildsystem.maven.MavenPlugin.Execution;
 import io.spring.initializr.generator.buildsystem.maven.MavenPlugin.Setting;
 import io.spring.initializr.generator.io.IndentingWriter;
+import io.spring.initializr.generator.version.VersionProperty;
 import io.spring.initializr.generator.version.VersionReference;
 
 /**
@@ -55,7 +57,7 @@ public class MavenBuildWriter {
 			writeProjectCoordinates(writer, settings);
 			writePackaging(writer, settings);
 			writeProjectName(writer, settings);
-			writeProperties(writer, build);
+			writeProperties(writer, build.properties());
 			writeDependencies(writer, build);
 			writeDependencyManagement(writer, build);
 			writeBuild(writer, build);
@@ -110,15 +112,15 @@ public class MavenBuildWriter {
 		writeSingleElement(writer, "description", settings.getDescription());
 	}
 
-	private void writeProperties(IndentingWriter writer, MavenBuild build) {
+	private void writeProperties(IndentingWriter writer, PropertyContainer properties) {
-		if (build.getProperties().isEmpty() && build.getVersionProperties().isEmpty()) {
+		if (properties.isEmpty()) {
 			return;
 		}
 		writer.println();
 		writeElement(writer, "properties", () -> {
-			build.getProperties().forEach((key, value) -> writeSingleElement(writer, key, value));
+			properties.values().forEach((entry) -> writeSingleElement(writer, entry.getKey(), entry.getValue()));
-			build.getVersionProperties()
+			properties.versions((VersionProperty::toStandardFormat))
-					.forEach((key, value) -> writeSingleElement(writer, key.toStandardFormat(), value));
+					.forEach((entry) -> writeSingleElement(writer, entry.getKey(), entry.getValue()));
 		});
 	}
 

initializr-generator/src/test/java/io/spring/initializr/generator/buildsystem/gradle/GroovyDslGradleBuildWriterTests.java

@@ -205,7 +205,7 @@ class GroovyDslGradleBuildWriterTests {
 	@Test
 	void gradleBuildWithExt() throws Exception {
 		GradleBuild build = new GradleBuild();
-		build.ext("java.version", "'1.8'").ext("alpha", "file(\"build/example\")");
+		build.properties().property("java.version", "'1.8'").property("alpha", "file(\"build/example\")");
 		List<String> lines = generateBuild(build);
 		assertThat(lines).containsSequence("    set('alpha', file(\"build/example\"))",
 				"    set('java.version', '1.8')");
@@ -214,12 +214,11 @@ class GroovyDslGradleBuildWriterTests {
 	@Test
 	void gradleBuildWithVersionProperties() throws IOException {
 		GradleBuild build = new GradleBuild();
-		build.addVersionProperty(VersionProperty.of("version.property"), "1.2.3");
+		build.properties().version(VersionProperty.of("version.property", false), "1.2.3")
-		build.addInternalVersionProperty("internal.property", "4.5.6");
+				.version(VersionProperty.of("internal.property", true), "4.5.6").version("external.property", "7.8.9");
-		build.addExternalVersionProperty("external.property", "7.8.9");
 		List<String> lines = generateBuild(build);
 		assertThat(lines).containsSequence("ext {", "    set('external.property', \"7.8.9\")",
-				"    set('internalProperty', \"4.5.6\")", "    set('versionProperty', \"1.2.3\")", "}");
+				"    set('internalProperty', \"4.5.6\")", "    set('version.property', \"1.2.3\")", "}");
 	}
 
 	@Test
@@ -248,9 +247,8 @@ class GroovyDslGradleBuildWriterTests {
 	@Test
 	void gradleBuildWithExtAndVersionProperties() throws Exception {
 		GradleBuild build = new GradleBuild();
-		build.addInternalVersionProperty("test-version", "1.0");
+		build.properties().version(VersionProperty.of("test-version"), "1.0").version("alpha-version", "0.1")
-		build.addExternalVersionProperty("alpha-version", "0.1");
+				.property("myProperty", "'42'");
-		build.ext("myProperty", "'42'");
 		List<String> lines = generateBuild(build);
 		assertThat(lines).containsSequence("    set('myProperty', '42')", "    set('alpha-version', \"0.1\")",
 				"    set('testVersion', \"1.0\")");

initializr-generator/src/test/java/io/spring/initializr/generator/buildsystem/gradle/KotlinDslGradleBuildWriterTests.java

@@ -210,7 +210,7 @@ class KotlinDslGradleBuildWriterTests {
 	@Test
 	void gradleBuildWithExt() throws Exception {
 		GradleBuild build = new GradleBuild();
-		build.ext("java.version", "\"1.8\"").ext("alpha", "file(\"build/example\")");
+		build.properties().property("java.version", "\"1.8\"").property("alpha", "file(\"build/example\")");
 		List<String> lines = generateBuild(build);
 		assertThat(lines).containsSequence("extra[\"alpha\"] = file(\"build/example\")",
 				"extra[\"java.version\"] = \"1.8\"");
@@ -219,12 +219,11 @@ class KotlinDslGradleBuildWriterTests {
 	@Test
 	void gradleBuildWithVersionProperties() throws IOException {
 		GradleBuild build = new GradleBuild();
-		build.addVersionProperty(VersionProperty.of("version.property"), "1.2.3");
+		build.properties().version(VersionProperty.of("version.property", false), "1.2.3")
-		build.addInternalVersionProperty("internal.property", "4.5.6");
+				.version(VersionProperty.of("internal.property", true), "4.5.6").version("external.property", "7.8.9");
-		build.addExternalVersionProperty("external.property", "7.8.9");
 		List<String> lines = generateBuild(build);
 		assertThat(lines).containsSequence("extra[\"external.property\"] = \"7.8.9\"",
-				"extra[\"internalProperty\"] = \"4.5.6\"", "extra[\"versionProperty\"] = \"1.2.3\"");
+				"extra[\"internalProperty\"] = \"4.5.6\"", "extra[\"version.property\"] = \"1.2.3\"");
 	}
 
 	@Test
@@ -253,9 +252,8 @@ class KotlinDslGradleBuildWriterTests {
 	@Test
 	void gradleBuildWithExtAndVersionProperties() throws Exception {
 		GradleBuild build = new GradleBuild();
-		build.addInternalVersionProperty("test-version", "1.0");
+		build.properties().version(VersionProperty.of("test-version", true), "1.0").version("alpha-version", "0.1")
-		build.addExternalVersionProperty("alpha-version", "0.1");
+				.property("myProperty", "42");
-		build.ext("myProperty", "42");
 		List<String> lines = generateBuild(build);
 		assertThat(lines).containsSequence("extra[\"myProperty\"] = 42", "extra[\"alpha-version\"] = \"0.1\"",
 				"extra[\"testVersion\"] = \"1.0\"");

initializr-generator/src/test/java/io/spring/initializr/generator/buildsystem/maven/MavenBuildWriterTests.java

@@ -86,8 +86,7 @@ class MavenBuildWriterTests {
 	void pomWithProperties() throws Exception {
 		MavenBuild build = new MavenBuild();
 		build.settings().coordinates("com.example.demo", "demo");
-		build.setProperty("java.version", "1.8");
+		build.properties().property("java.version", "1.8").property("alpha", "a");
-		build.setProperty("alpha", "a");
 		generatePom(build, (pom) -> {
 			assertThat(pom).textAtPath("/project/properties/java.version").isEqualTo("1.8");
 			assertThat(pom).textAtPath("/project/properties/alpha").isEqualTo("a");
@@ -97,9 +96,8 @@ class MavenBuildWriterTests {
 	@Test
 	void pomWithVersionProperties() throws Exception {
 		MavenBuild build = new MavenBuild();
-		build.addVersionProperty(VersionProperty.of("version.property"), "1.2.3");
+		build.properties().version(VersionProperty.of("version.property", false), "1.2.3")
-		build.addInternalVersionProperty("internal.property", "4.5.6");
+				.version(VersionProperty.of("internal.property", true), "4.5.6").version("external.property", "7.8.9");
-		build.addExternalVersionProperty("external.property", "7.8.9");
 		generatePom(build, (pom) -> {
 			assertThat(pom).textAtPath("/project/properties/version.property").isEqualTo("1.2.3");
 			assertThat(pom).textAtPath("/project/properties/internal.property").isEqualTo("4.5.6");