Use project name to infer the name of the app

The 'name' field can now be used to customize the name of the generated
application (and its test counterpart). A default application name is
used If no suitable identifier can be inferred from the specified name.

Concretely, this means that the default application name is no longer
`Application` but `DemoApplication` since the default name is `demo`.

Closes gh-60

initializr/src/main/groovy/io/spring/initializr/InitializrMetadata.groovy

@@ -297,10 +297,13 @@ class InitializrMetadata {
 	}
 
 	static class Defaults {
+
+		static final String DEFAULT_NAME = 'demo'
+
 		String groupId = 'org.test'
 		String artifactId
 		String version = '0.0.1-SNAPSHOT'
-		String name = 'demo'
+		String name = DEFAULT_NAME
 		String description = 'Demo project for Spring Boot'
 		String packageName
 		String type

initializr/src/main/groovy/io/spring/initializr/ProjectGenerator.groovy

@@ -84,14 +84,16 @@ class ProjectGenerator {
 			new File(dir, 'pom.xml').write(pom)
 		}
 
+		def applicationName = request.applicationName
 		def language = request.language
 
 		def src = new File(new File(dir, "src/main/$language"), request.packageName.replace('.', '/'))
 		src.mkdirs()
-		write(src, "Application.$language", model)
+		write(new File(src, "${applicationName}.${language}"), "Application.$language", model)
 
 		if (request.packaging == 'war') {
-			write(src, "ServletInitializer.$language", model)
+			def fileName = "ServletInitializer.$language"
+			write(new File(src, fileName), fileName, model)
 		}
 
 		def test = new File(new File(dir, "src/test/$language"), request.packageName.replace('.', '/'))
@@ -103,7 +105,7 @@ class ProjectGenerator {
 			model.testAnnotations = ''
 			model.testImports = ''
 		}
-		write(test, "ApplicationTests.$language", model)
+		write(new File(test, "${applicationName}Tests.${language}"), "ApplicationTests.$language", model)
 
 		def resources = new File(dir, 'src/main/resources')
 		resources.mkdirs()
@@ -174,10 +176,10 @@ class ProjectGenerator {
 		template 'starter-build.gradle', model
 	}
 
-	def write(File src, String name, def model) {
-		def tmpl = name.endsWith('.groovy') ? name + '.tmpl' : name
+	def write(File target, String templateName, def model) {
+		def tmpl = templateName.endsWith('.groovy') ? templateName + '.tmpl' : templateName
 		def body = template tmpl, model
-		new File(src, name).write(body)
+		target.write(body)
 	}
 
 	private void addTempFile(String group, File file) {

initializr/src/main/groovy/io/spring/initializr/ProjectRequest.groovy

@@ -33,6 +33,11 @@ class ProjectRequest {
 	 */
 	static final DEFAULT_STARTER = 'root_starter'
 
+	/**
+	 * The default name of the application class.
+	 */
+	static final String DEFAULT_APPLICATION_NAME = 'Application'
+
 	List<String> style = []
 	List<String> dependencies = []
 	String name
@@ -43,6 +48,7 @@ class ProjectRequest {
 	String version
 	String bootVersion
 	String packaging
+	String applicationName
 	String language
 	String packageName
 	String javaVersion
@@ -88,6 +94,11 @@ class ProjectRequest {
 				this.build = buildTag
 			}
 		}
+
+		if (!applicationName) {
+			this.applicationName = generateApplicationName(this.name, DEFAULT_APPLICATION_NAME)
+		}
+
 		afterResolution(metadata)
 	}
 
@@ -114,7 +125,6 @@ class ProjectRequest {
 		root.id = DEFAULT_STARTER
 		root.asSpringBootStarter('')
 		resolvedDependencies << root
-
 	}
 
 	/**
@@ -131,4 +141,51 @@ class ProjectRequest {
 		facets.contains(facet)
 	}
 
+	/**
+	 * Generate a suitable application mame based on the specified name. If no suitable
+	 * application name can be generated from the specified {@code name}, the
+	 * {@code defaultApplicationName} is used instead.
+	 * <p>No suitable application name can be generated if the name is {@code null} or
+	 * if it contains an invalid character for a class identifier.
+	 */
+	static String generateApplicationName(String name, String defaultApplicationName) {
+		if (!name) {
+			return defaultApplicationName
+		}
+		String text = splitCamelCase(name.trim())
+		String result = text.replaceAll("(_|-| |:)+([A-Za-z0-9])", { Object[] it ->
+			it[2].toUpperCase()
+		})
+		if (!result.endsWith('Application')) {
+			result += 'Application'
+		}
+		String candidate = result.capitalize();
+		if (hasInvalidChar(candidate)) {
+			return defaultApplicationName
+		} else {
+			return candidate
+		}
+	}
+
+	private static String splitCamelCase(String text) {
+		text.split('(?<!(^|[A-Z]))(?=[A-Z])|(?<!^)(?=[A-Z][a-z])').collect {
+			String s = it.toLowerCase()
+			s.capitalize()
+		}.join("")
+	}
+
+	private static boolean hasInvalidChar(String text) {
+		if (!Character.isJavaIdentifierStart(text.charAt(0))) {
+			return true
+		}
+		if (text.length() > 1) {
+			for (int i = 1; i < text.length(); i++) {
+				if (!Character.isJavaIdentifierPart(text.charAt(i))) {
+					return true
+				}
+			}
+		}
+		return false
+	}
+
 }

initializr/src/main/resources/templates/Application.groovy.tmpl

@@ -8,9 +8,9 @@ import org.springframework.context.annotation.Configuration
 @Configuration
 @ComponentScan
 @EnableAutoConfiguration
-class Application {
+class ${applicationName} {
 
     static void main(String[] args) {
-        SpringApplication.run Application, args
+        SpringApplication.run ${applicationName}, args
     }
 }

initializr/src/main/resources/templates/Application.java

@@ -8,9 +8,9 @@ import org.springframework.context.annotation.Configuration;
 @Configuration
 @ComponentScan
 @EnableAutoConfiguration
-public class Application {
+public class ${applicationName} {
 
     public static void main(String[] args) {
-        SpringApplication.run(Application.class, args);
+        SpringApplication.run(${applicationName}.class, args);
     }
 }

initializr/src/main/resources/templates/ApplicationTests.groovy.tmpl

@@ -6,8 +6,8 @@ ${testImports}import org.springframework.boot.test.SpringApplicationConfiguratio
 import org.springframework.test.context.junit4.SpringJUnit4ClassRunner
 
 @RunWith(SpringJUnit4ClassRunner)
-@SpringApplicationConfiguration(classes = Application)
-${testAnnotations}class ApplicationTests {
+@SpringApplicationConfiguration(classes = ${applicationName})
+${testAnnotations}class ${applicationName}Tests {
 
 	@Test
 	void contextLoads() {

initializr/src/main/resources/templates/ApplicationTests.java

@@ -6,8 +6,8 @@ ${testImports}import org.springframework.boot.test.SpringApplicationConfiguratio
 import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
 
 @RunWith(SpringJUnit4ClassRunner.class)
-@SpringApplicationConfiguration(classes = Application.class)
-${testAnnotations}public class ApplicationTests {
+@SpringApplicationConfiguration(classes = ${applicationName}.class)
+${testAnnotations}public class ${applicationName}Tests {
 
 	@Test
 	public void contextLoads() {

initializr/src/main/resources/templates/ServletInitializer.groovy.tmpl

@@ -3,11 +3,11 @@ package ${packageName}
 import org.springframework.boot.builder.SpringApplicationBuilder
 import org.springframework.boot.context.web.SpringBootServletInitializer
 
-class ServletInitializer  extends SpringBootServletInitializer {
+class ServletInitializer extends SpringBootServletInitializer {
 
 	@Override
 	protected SpringApplicationBuilder configure(SpringApplicationBuilder application) {
-		application.sources(Application)
+		application.sources(${applicationName})
 	}
 
 }

initializr/src/main/resources/templates/ServletInitializer.java

@@ -7,7 +7,7 @@ public class ServletInitializer extends SpringBootServletInitializer {
 
 	@Override
 	protected SpringApplicationBuilder configure(SpringApplicationBuilder application) {
-		return application.sources(Application.class);
+		return application.sources(${applicationName}.class);
 	}
 
 }

initializr/src/main/resources/templates/starter-pom.xml

@@ -20,7 +20,7 @@
 
 	<properties>
 		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
-		<start-class>${packageName}.Application</start-class>
+		<start-class>${packageName}.${applicationName}</start-class>
 		<java.version>${javaVersion}</java.version>
 	</properties>
 

initializr/src/test/groovy/io/spring/initializr/ProjectGeneratorTests.groovy

@@ -51,7 +51,7 @@ class ProjectGeneratorTests {
 		projectGenerator.listeners << listener
 
 		def request = createProjectRequest('web')
-		generateMavenPom(request).hasStartClass('demo.Application')
+		generateMavenPom(request).hasStartClass('demo.DemoApplication')
 				.hasNoRepository().hasSpringBootStarterDependency('web')
 		verify(listener, times(1)).onGeneratedProject(request)
 	}
@@ -73,7 +73,7 @@ class ProjectGeneratorTests {
 
 		def request = createProjectRequest('web')
 		generateProject(request).isJavaProject().isMavenProject().pomAssert()
-				.hasStartClass('demo.Application').hasNoRepository().hasSpringBootStarterDependency('web')
+				.hasStartClass('demo.DemoApplication').hasNoRepository().hasSpringBootStarterDependency('web')
 		verify(listener, times(1)).onGeneratedProject(request)
 	}
 
@@ -88,7 +88,7 @@ class ProjectGeneratorTests {
 	void mavenPomWithBootSnapshot() {
 		def request = createProjectRequest('web')
 		request.bootVersion = '1.0.1.BUILD-SNAPSHOT'
-		generateMavenPom(request).hasStartClass('demo.Application')
+		generateMavenPom(request).hasStartClass('demo.DemoApplication')
 				.hasSnapshotRepository().hasSpringBootStarterDependency('web')
 	}
 
@@ -105,7 +105,7 @@ class ProjectGeneratorTests {
 		projectGenerator.metadata = metadata
 
 		def request = createProjectRequest('thymeleaf')
-		generateMavenPom(request).hasStartClass('demo.Application')
+		generateMavenPom(request).hasStartClass('demo.DemoApplication')
 				.hasDependency('org.foo', 'thymeleaf')
 				.hasDependenciesCount(2)
 
@@ -125,7 +125,7 @@ class ProjectGeneratorTests {
 
 		def request = createProjectRequest('thymeleaf')
 		request.packaging = 'war'
-		generateMavenPom(request).hasStartClass('demo.Application')
+		generateMavenPom(request).hasStartClass('demo.DemoApplication')
 				.hasSpringBootStarterDependency('tomcat')
 				.hasDependency('org.foo', 'thymeleaf') // This is tagged as web facet so it brings the web one
 				.hasSpringBootStarterDependency('test')
@@ -137,7 +137,7 @@ class ProjectGeneratorTests {
 	void mavenWarPomWithoutWebFacet() {
 		def request = createProjectRequest('data-jpa')
 		request.packaging = 'war'
-		generateMavenPom(request).hasStartClass('demo.Application')
+		generateMavenPom(request).hasStartClass('demo.DemoApplication')
 				.hasSpringBootStarterDependency('tomcat')
 				.hasSpringBootStarterDependency('data-jpa')
 				.hasSpringBootStarterDependency('web') // Added by war packaging

initializr/src/test/groovy/io/spring/initializr/ProjectRequestTests.groovy

@@ -29,6 +29,8 @@ import static org.junit.Assert.assertNull
  */
 class ProjectRequestTests {
 
+	private static final String DEFAULT_APPLICATION_NAME = 'FooBarApplication'
+
 	@Rule
 	public final ExpectedException thrown = ExpectedException.none()
 
@@ -127,6 +129,105 @@ class ProjectRequestTests {
 		request.resolve(metadata)
 	}
 
+	@Test
+	void resolveApplicationNameWithNoName() {
+		def request = new ProjectRequest()
+		def metadata = InitializrMetadataBuilder.withDefaults().validateAndGet()
+
+		request.resolve(metadata)
+		assertEquals ProjectRequest.DEFAULT_APPLICATION_NAME, request.applicationName
+	}
+
+	@Test
+	void resolveApplicationName() {
+		def request = new ProjectRequest()
+		request.name = 'Foo2'
+		def metadata = InitializrMetadataBuilder.withDefaults().validateAndGet()
+
+		request.resolve(metadata)
+		assertEquals 'Foo2Application', request.applicationName
+	}
+
+	@Test
+	void resolveApplicationNameWithApplicationNameSet() {
+		def request = new ProjectRequest()
+		request.name = 'Foo2'
+		request.applicationName ='MyApplicationName'
+		def metadata = InitializrMetadataBuilder.withDefaults().validateAndGet()
+
+		request.resolve(metadata)
+		assertEquals 'MyApplicationName', request.applicationName
+	}
+
+	@Test
+	void generateApplicationNameSimple() {
+		assertEquals 'DemoApplication', generateApplicationName('demo')
+	}
+
+	@Test
+	void generateApplicationNameSimpleApplication() {
+		assertEquals 'DemoApplication', generateApplicationName('demoApplication')
+	}
+
+	@Test
+	void generateApplicationNameSimpleCamelCase() {
+		assertEquals 'MyDemoApplication', generateApplicationName('myDemo')
+	}
+
+	@Test
+	void generateApplicationNameSimpleUnderscore() {
+		assertEquals 'MyDemoApplication', generateApplicationName('my_demo')
+	}
+
+	@Test
+	void generateApplicationNameSimpleColon() {
+		assertEquals 'MyDemoApplication', generateApplicationName('my:demo')
+	}
+
+	@Test
+	void generateApplicationNameSimpleSpace() {
+		assertEquals 'MyDemoApplication', generateApplicationName('my demo')
+	}
+
+	@Test
+	void generateApplicationNamSsimpleDash() {
+		assertEquals 'MyDemoApplication', generateApplicationName('my-demo')
+	}
+
+	@Test
+	void generateApplicationNameUpperCaseUnderscore() {
+		assertEquals 'MyDemoApplication', generateApplicationName('MY_DEMO')
+	}
+
+	@Test
+	void generateApplicationNameUpperCaseDash() {
+		assertEquals 'MyDemoApplication', generateApplicationName('MY-DEMO')
+	}
+
+	@Test
+	void generateApplicationNameMultiSpaces() {
+		assertEquals 'MyDemoApplication', generateApplicationName('   my    demo ')
+	}
+
+	@Test
+	void generateApplicationNameMultiSpacesUpperCase() {
+		assertEquals 'MyDemoApplication', generateApplicationName('   MY    DEMO ')
+	}
+
+	@Test
+	void generateApplicationNameInvalidStartCharacter() {
+		assertEquals DEFAULT_APPLICATION_NAME, generateApplicationName('1MyDemo')
+	}
+
+	@Test
+	void generateApplicationNameInvalidPartCharacter() {
+		assertEquals DEFAULT_APPLICATION_NAME, generateApplicationName('MyDe|mo')
+	}
+
+	private static generateApplicationName(String text) {
+		ProjectRequest.generateApplicationName(text, DEFAULT_APPLICATION_NAME)
+	}
+
 	private static void assertBootStarter(InitializrMetadata.Dependency actual, String name) {
 		def expected = new InitializrMetadata.Dependency()
 		expected.asSpringBootStarter(name)

initializr/src/test/groovy/io/spring/initializr/support/ProjectAssert.groovy

@@ -16,6 +16,8 @@
 
 package io.spring.initializr.support
 
+import io.spring.initializr.InitializrMetadata
+
 import static org.junit.Assert.assertEquals
 
 /**
@@ -26,6 +28,8 @@ import static org.junit.Assert.assertEquals
  */
 class ProjectAssert {
 
+	private static final DEFAULT_APPLICATION_NAME = generateDefaultApplicationName()
+
 	final File dir
 
 	/**
@@ -51,17 +55,25 @@ class ProjectAssert {
 		hasFile('build.gradle').hasNoFile('pom.xml')
 	}
 
-	ProjectAssert isJavaProject() {
-		hasFile('src/main/java/demo/Application.java',
-				'src/test/java/demo/ApplicationTests.java',
+	ProjectAssert isJavaProject(String expectedApplicationName) {
+		hasFile("src/main/java/demo/${expectedApplicationName}.java",
+				"src/test/java/demo/${expectedApplicationName}Tests.java",
 				'src/main/resources/application.properties')
 	}
 
-	ProjectAssert isJavaWarProject() {
-		isJavaProject().hasStaticAndTemplatesResources(true)
+	ProjectAssert isJavaProject() {
+		isJavaProject(DEFAULT_APPLICATION_NAME)
+	}
+
+	ProjectAssert isJavaWarProject(String expectedApplicationName) {
+		isJavaProject(expectedApplicationName).hasStaticAndTemplatesResources(true)
 				.hasFile('src/main/java/demo/ServletInitializer.java')
 	}
 
+	ProjectAssert isJavaWarProject() {
+		isJavaWarProject(DEFAULT_APPLICATION_NAME)
+	}
+
 	ProjectAssert hasStaticAndTemplatesResources(boolean web) {
 		assertFile('src/main/resources/templates', web)
 		assertFile('src/main/resources/static', web)
@@ -91,4 +103,8 @@ class ProjectAssert {
 		new File(dir, localPath)
 	}
 
+	private static generateDefaultApplicationName() {
+		InitializrMetadata.Defaults.DEFAULT_NAME.capitalize() + 'Application'
+	}
+
 }

initializr/src/test/groovy/io/spring/initializr/web/AbstractInitializerControllerFormIntegrationTests.groovy

@@ -86,7 +86,8 @@ abstract class AbstractInitializerControllerFormIntegrationTests extends Abstrac
 		assertEquals  'attachment; filename="foo-bar.zip"', value
 
 		def projectAssert = zipProjectAssert(webResponse)
-		projectAssert.isMavenProject().isJavaProject().hasStaticAndTemplatesResources(true)
+		projectAssert.isMavenProject().isJavaProject('MyProjectApplication')
+				.hasStaticAndTemplatesResources(true)
 
 		projectAssert.pomAssert().hasGroupId('com.acme').hasArtifactId('foo-bar')
 				.hasName('My project').hasDescription('A description for my project')

initializr/src/test/groovy/io/spring/initializr/web/MainControllerDefaultsIntegrationTests.groovy

@@ -20,7 +20,7 @@ class MainControllerDefaultsIntegrationTests extends AbstractInitializrControlle
 		def content = restTemplate.getForObject(createUrl('/pom.xml?style=web'), String)
 		def pomAssert = new PomAssert(content)
 		pomAssert.hasGroupId('org.foo').hasArtifactId('foo-bar').hasVersion('1.2.4-SNAPSHOT').hasPackaging('jar')
-				.hasName('FooBar').hasDescription('FooBar Project').hasStartClass('org.foo.demo.Application')
+				.hasName('FooBar').hasDescription('FooBar Project').hasStartClass('org.foo.demo.FooBarApplication')
 	}
 
 	@Test