Spring Framework<\/a> is a Java application framework that provides many useful services for building applications.<\/p>\n Vaadin<\/a> provides a Vaadin Spring<\/a> add-on based on the core parts of vaadin4spring<\/a> to make classes for UI and View as Spring managed beans so Spring dependency injection<\/a> can be used.<\/p>\n In this example, I will demonstrate how to build a Single Paged Application (SPA) with Vaadin Spring<\/a>.\n<\/p>\n The example code in this article was built and run using:<\/p>\n The easiest way to generate a Spring-boot Vaadin application is via the Spring starter tool with the steps below:<\/p>\n A maven project will be generated and downloaded to your workstation. Import it into your Eclipse workspace.<\/p>\n The generated pom.xml<\/em><\/span><\/p>\n The generated VaadinSpringDemoApplication.java<\/em><\/span><\/p>\n Execute If you have not worked with Vaadin before, please check it out here<\/a>.<\/p>\n Vaadin-Spring add-on API includes the annotations below:<\/p>\n The easiest way to set up your navigation in a SPA is to use the Vaadin Spring In case you were wondering, In this example, we will create two Spring Beans, annotate them with The lifecycle of View-scoped beans starts when the user navigates to a view referring to the object and ends when the user navigates out of the view or when the UI is closed or expires.<\/p>\n In this step, we will create DemoViewScopeBean.java<\/em><\/span><\/p>\n The lifecycle of UI-scoped beans is bound between the initialization and closing of a UI. UI-scoped beans are uniquely identified within a UI instance, that is, a browser window or tab. When injecting a bean, the same instance bean will be used if within the same UI. In this step, we will create DemoUIScopeBean.java<\/em><\/span><\/p>\n The In this step, we will create In this step, we will create two views – DefaultView.java<\/em><\/span><\/p>\n ViewScopeView.java<\/em><\/span><\/p>\n Please note that In this step, we will create two views – UIScopeView.java<\/em><\/span><\/p>\n ErrorView.java<\/em><\/span><\/p>\n Vaadin Spring provides At this step, we will create MainUI.java<\/em><\/span><\/p>\n Execute Spring-boot output indicates the web application is up.<\/p>\n application output<\/em><\/span><\/p>\n Go to Click the “UI_Scoped View” button. It will display a response from Click the “View_Scoped View” button. It will display a message from Note<\/strong>: In this example, we built a Vaadin Spring Boot web application via the Vaadin-Spring starter and then modified it with UI components annotated with Vaadin-Spring Add-on annotations. We demonstrated that Vaadin Spring Add-on provides an easier way to allow the UI and View classes to access the Spring dependency injection feature.<\/p>\n You can use the Vaadin-Spring in non Spring Boot web application. I have another article with more details, please check it out here<\/a>.<\/p>\n This example consists of a Spring-boot Vaadin web application.<\/p>\n2. Technologies Used<\/h2>\n
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3. Spring-boot Vaadin Web Application<\/h2>\n
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https:\/\/start.spring.io\/<\/code>.<\/li>\nMaven Project<\/code> with Java<\/code> and Spring Boot version 1.5.10 and type in Vaadin<\/code> in the “search for dependencies” bar.<\/li>\njcg.zheng.demo<\/code> and artifact as vaadin-spring-demo<\/code>.<\/li>\nGenerate Project<\/code> button.<\/li>\n<\/ol>\n![\"Generate](\"http:\/\/examples.javacodegeeks.com\/wp-content\/uploads\/2018\/02\/vaadin-spring.jpg\")
<\/a>3.1 POM<\/h3>\n
pom.xml<\/code> includes vaadin-spring-boot-starter<\/code>. There is no modification needed in this example.<\/p>\n<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n<project xmlns=\"http:\/\/maven.apache.org\/POM\/4.0.0\" xmlns:xsi=\"http:\/\/www.w3.org\/2001\/XMLSchema-instance\"\n\txsi:schemaLocation=\"http:\/\/maven.apache.org\/POM\/4.0.0 http:\/\/maven.apache.org\/xsd\/maven-4.0.0.xsd\">\n\t<modelVersion>4.0.0<\/modelVersion>\n\n\t<groupId>jcg.zheng.demo<\/groupId>\n\t<artifactId>vaadin-spring-demo<\/artifactId>\n\t<version>0.0.1-SNAPSHOT<\/version>\n\t<packaging>jar<\/packaging>\n\n\t<name>vaadin-spring-demo<\/name>\n\t<description>Demo project for Spring Boot<\/description>\n\n\t<parent>\n\t\t<groupId>org.springframework.boot<\/groupId>\n\t\t<artifactId>spring-boot-starter-parent<\/artifactId>\n\t\t<version>1.5.10.RELEASE<\/version>\n\t\t<relativePath\/> <!-- lookup parent from repository -->\n\t<\/parent>\n\n\t<properties>\n\t\t<project.build.sourceEncoding>UTF-8<\/project.build.sourceEncoding>\n\t\t<project.reporting.outputEncoding>UTF-8<\/project.reporting.outputEncoding>\n\t\t<java.version>1.8<\/java.version>\n\t\t<vaadin.version>8.3.0<\/vaadin.version>\n\t<\/properties>\n\n\t<dependencies>\n\t\t<dependency>\n\t\t\t<groupId>com.vaadin<\/groupId>\n\t\t\t<artifactId>vaadin-spring-boot-starter<\/artifactId>\n\t\t<\/dependency>\n\n\t\t<dependency>\n\t\t\t<groupId>org.springframework.boot<\/groupId>\n\t\t\t<artifactId>spring-boot-starter-test<\/artifactId>\n\t\t\t<scope>test<\/scope>\n\t\t<\/dependency>\n\t<\/dependencies>\n\n\t<dependencyManagement>\n\t\t<dependencies>\n\t\t\t<dependency>\n\t\t\t\t<groupId>com.vaadin<\/groupId>\n\t\t\t\t<artifactId>vaadin-bom<\/artifactId>\n\t\t\t\t<version>${vaadin.version}<\/version>\n\t\t\t\t<type>pom<\/type>\n\t\t\t\t<scope>import<\/scope>\n\t\t\t<\/dependency>\n\t\t<\/dependencies>\n\t<\/dependencyManagement>\n\n\t<build>\n\t\t<plugins>\n\t\t\t<plugin>\n\t\t\t\t<groupId>org.springframework.boot<\/groupId>\n\t\t\t\t<artifactId>spring-boot-maven-plugin<\/artifactId>\n\t\t\t<\/plugin>\n\t\t<\/plugins>\n\t<\/build>\n\n\n<\/project>\n<\/pre>\n3.2 Vaadin Spring Demo Application<\/h3>\n
VaadinSpringDemoApplication.java<\/code> is annotated with @SpringBootApplication<\/code>. It is equivalent to using @Configuration<\/code>, @EnableAutoConfiguration<\/code>, and @ComponentScan<\/code>with their default attributes. In this example there is also no modification needed.<\/p>\npackage jcg.zheng.demo.spring;\n\nimport org.springframework.boot.SpringApplication;\nimport org.springframework.boot.autoconfigure.SpringBootApplication;\n\n@SpringBootApplication\npublic class VaadinSpringDemoApplication {\n\n\tpublic static void main(String[] args) {\n\t\tSpringApplication.run(VaadinSpringDemoApplication.class, args);\n\t}\n}\n<\/pre>\nmvn clean install<\/code> to build the project. You should be able to start it as a Java Application.<\/p>\n4. Single Paged Vaadin Application<\/h2>\n
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@SpringViewDisplay<\/code> on the UI class, in which case the whole contents of the UI is replaced based on the navigation. In this example, we will create a main UI class, which contains two navigation buttons. It will switch to the dedicated view when the correct button is clicked.<\/p>\n4.1 Spring Beans<\/h3>\n
@SpringComponent<\/code> annotation allows for automatic detection of beans managed by Spring.<\/p>\n@SpringComponent<\/code> is exactly the same as the regular Spring @Component<\/code>, but has been given an alias, because Vaadin already has a Component<\/code> interface.<\/p>\n@ViewScope<\/code> and @UIScope<\/code> respectively.<\/p>\n4.1.1 Bean with @ViewScope<\/h4>\n
DemoViewScopeBean<\/code> with @ViewScope<\/code> annotation. This bean will be used later at step 4.2.1<\/a>.<\/p>\npackage jcg.zheng.demo.spring;\n\nimport com.vaadin.spring.annotation.SpringComponent;\nimport com.vaadin.spring.annotation.ViewScope;\n\n@SpringComponent\n@ViewScope\npublic class DemoViewScopeBean {\n\tpublic String getData() {\n\t\treturn \"Same bean instance for same view. bean=\"\n\t\t\t\t+ toString();\n\n\t}\n}<\/pre>\n4.1.2 Bean with @UIScope<\/h4>\n
DemoUIScopeBean<\/code> with @UIScope<\/code> annotation. This bean will be used later at steps 4.2.1<\/a> and 4.2.2<\/a>.<\/p>\npackage jcg.zheng.demo.spring;\n\nimport com.vaadin.spring.annotation.SpringComponent;\nimport com.vaadin.spring.annotation.UIScope;\n\n@SpringComponent\n@UIScope\npublic class DemoUIScopeBean {\n\tpublic String getData() {\n\t\treturn \"Same bean instance for same UI. bean=\" + toString();\n\t}\n}<\/pre>\n4.2 Spring Views<\/h3>\n
@SpringView<\/code> annotation enables Spring injection features in the view classes. The SpringViewProvider<\/code> fetches the views from the Spring application context and registers them so that these views can be managed by @SpringViewDisplay<\/code>.<\/p>\nViewScopeView<\/code> and DefaultView<\/code> and annotate them with @ViewScope<\/code> and UIScopeView<\/code> and ErrorView<\/code> and annotate them with @UIScope<\/code>.<\/p>\n<\/a>4.2.1 View with @ViewScope<\/h4>\n
DefaultView<\/code> and ViewScopeView<\/code> with @ViewScope<\/code> annotation.<\/p>\nDefaultView<\/code> is the one used when the web application starts.<\/p>\npackage jcg.zheng.demo.spring.view;\n\nimport javax.annotation.PostConstruct;\n\nimport com.vaadin.navigator.View;\nimport com.vaadin.navigator.ViewChangeListener.ViewChangeEvent;\nimport com.vaadin.spring.annotation.SpringView;\nimport com.vaadin.ui.Label;\nimport com.vaadin.ui.VerticalLayout;\n\n@SpringView(name = DefaultView.VIEW_NAME)\npublic class DefaultView extends VerticalLayout implements View {\n\n\tprivate static final long serialVersionUID = -3903205444585313680L;\n\tpublic static final String VIEW_NAME = \"\"; \/\/default\n\n @PostConstruct\n void init() {\n addComponent(new Label(\"Welcome to Vaadin-Spring Demo!!\"));\n }\n\n @Override\n public void enter(ViewChangeEvent event) {\n \/\/ This view is constructed in the init() method()\n }\n}<\/pre>\nViewScopeView<\/code> is the one used when the View_Scoped View<\/code> button is clicked.<\/p>\npackage jcg.zheng.demo.spring.view;\n\nimport javax.annotation.PostConstruct;\n\nimport org.springframework.beans.factory.annotation.Autowired;\n\nimport com.vaadin.navigator.View;\nimport com.vaadin.navigator.ViewChangeListener.ViewChangeEvent;\nimport com.vaadin.spring.annotation.SpringView;\nimport com.vaadin.ui.Label;\nimport com.vaadin.ui.VerticalLayout;\n\nimport jcg.zheng.demo.spring.DemoUIScopeBean;\nimport jcg.zheng.demo.spring.DemoViewScopeBean;\n\n@SpringView(name = ViewScopeView.VIEW_NAME)\npublic class ViewScopeView extends VerticalLayout implements View {\n\n\tprivate static final long serialVersionUID = 5784972560238064106L;\n\n\tpublic static final String VIEW_NAME = \"view\";\n\t\n\t\/\/ A new instance will be created for every view instance created\n @Autowired\n private DemoViewScopeBean viewBean;\n \n \/\/ The same instance will be used by all views of the UI\n @Autowired\n private DemoUIScopeBean uiBean;\n \n\n\t@PostConstruct\n\tvoid init() {\n\t\taddComponent(new Label(\"This is a view scoped view\"));\n\t\taddComponent(new Label( uiBean.getData()));\n\t\taddComponent(new Label( viewBean.getData()));\n\t}\n\n\t@Override\n\tpublic void enter(ViewChangeEvent event) {\n\t\t\/\/ This view is constructed in the init() method()\n\t}\n}\n<\/pre>\n<\/a>4.2.2 View with @UIScope<\/h4>\n
@UIScope<\/code> needs to be before @SpringView<\/code> because @SpringView<\/code> has default attribute of @ViewScope<\/code>.<\/p>\nUIScopeView<\/code> and ErrorView<\/code> with @UIScope<\/code> annotation.
\nUIScopeview<\/code> which contains a vertical layout and displays a label from DemoUIScopeBean<\/code>.<\/p>\npackage jcg.zheng.demo.spring.view;\n\nimport javax.annotation.PostConstruct;\n\nimport org.springframework.beans.factory.annotation.Autowired;\n\nimport com.vaadin.navigator.View;\nimport com.vaadin.navigator.ViewChangeListener.ViewChangeEvent;\nimport com.vaadin.spring.annotation.SpringView;\nimport com.vaadin.spring.annotation.UIScope;\nimport com.vaadin.ui.Label;\nimport com.vaadin.ui.VerticalLayout;\n\nimport jcg.zheng.demo.spring.DemoUIScopeBean;\n\n\/\/Annotation order is matter here, @UIScope is before @SpringView\n@UIScope\n@SpringView(name = UIScopeView.VIEW_NAME)\npublic class UIScopeView extends VerticalLayout implements View {\n\n\tprivate static final long serialVersionUID = -3089511061636116441L;\n\n\tpublic static final String VIEW_NAME = \"ui\";\n\n\t@Autowired\n\tprivate DemoUIScopeBean uiBean;\n\n\t@PostConstruct\n\tvoid init() {\n\t\taddComponent(new Label(\"This is a UI scoped view.\"));\n\t\taddComponent(new Label(\"uiBean says: \" + uiBean.getData()));\n\t}\n\n\t@Override\n\tpublic void enter(ViewChangeEvent event) {\n\t\t\/\/ This view is constructed in the init() method()\n\t}\n}\n<\/pre>\nErrorView<\/code> must be annotated with @UIScope<\/code> because the SPA handles errors for the entire UI.<\/p>\npackage jcg.zheng.demo.spring.view;\n\nimport javax.annotation.PostConstruct;\n\nimport com.vaadin.navigator.View;\nimport com.vaadin.navigator.ViewChangeListener.ViewChangeEvent;\nimport com.vaadin.spring.annotation.SpringView;\nimport com.vaadin.spring.annotation.UIScope;\nimport com.vaadin.ui.Label;\nimport com.vaadin.ui.VerticalLayout;\n\n@UIScope\n@SpringView(name = ErrorView.VIEW_NAME)\npublic class ErrorView extends VerticalLayout implements View {\n\n\tprivate static final long serialVersionUID = -134715779625065266L;\n\tpublic static final String VIEW_NAME = \"error\";\n\n @PostConstruct\n void init() {\n addComponent(new Label(\"This is the error view - Oops!\"));\n }\n\n @Override\n public void enter(ViewChangeEvent event) {\n \/\/ This view is constructed in the init() method()\n }\n}<\/pre>\n4.3 Spring UI<\/h3>\n
@SpringUI<\/code> to instantiate UIs and to define the URL mapping for them. The annotated UI will automatically be placed in the UIScope<\/code>.<\/p>\nMainUI<\/code>, which contains two navigation buttons. It will switch to the correct view when the corresponding button is clicked.<\/p>\npackage jcg.zheng.demo.spring.ui;\n\nimport com.vaadin.navigator.View;\nimport com.vaadin.navigator.ViewDisplay;\nimport com.vaadin.server.VaadinRequest;\nimport com.vaadin.spring.annotation.SpringUI;\nimport com.vaadin.spring.annotation.SpringViewDisplay;\nimport com.vaadin.ui.Button;\nimport com.vaadin.ui.Component;\nimport com.vaadin.ui.CssLayout;\nimport com.vaadin.ui.Label;\nimport com.vaadin.ui.Panel;\nimport com.vaadin.ui.UI;\nimport com.vaadin.ui.VerticalLayout;\nimport com.vaadin.ui.themes.ValoTheme;\n\nimport jcg.zheng.demo.spring.view.ErrorView;\nimport jcg.zheng.demo.spring.view.UIScopeView;\nimport jcg.zheng.demo.spring.view.ViewScopeView;\n\n@SpringUI(path = MainUI.APP_ROOT)\n@SpringViewDisplay\npublic class MainUI extends UI implements ViewDisplay {\n\n\tstatic final String APP_ROOT = \"\/vaadin-spring-demo\";\n\tprivate static final String VIEW_SCOPED_VIEW = \"View_Scoped View\";\n\tprivate static final String UI_SCOPED_VIEW = \"UI_Scoped View\";\n\tprivate static final long serialVersionUID = 4967383498113318791L;\n\tprivate Panel springViewDisplay;\n\n\t@Override\n\tprotected void init(VaadinRequest vaadinRequest) {\n\n\t\tfinal VerticalLayout root = new VerticalLayout();\n\t\troot.setSizeFull();\n\t\tsetContent(root);\n\n\t\tfinal CssLayout navigationBar = new CssLayout();\n\t\t\n\t\tnavigationBar.addStyleName(ValoTheme.LAYOUT_COMPONENT_GROUP);\n\t\n\t\tnavigationBar.addComponent(createNavigationButton(UI_SCOPED_VIEW, UIScopeView.VIEW_NAME));\n\t\tnavigationBar.addComponent(new Label(\" \"));\n\t\tnavigationBar.addComponent(createNavigationButton(VIEW_SCOPED_VIEW, ViewScopeView.VIEW_NAME));\n\t\n\t\troot.addComponent(navigationBar);\n\n\t\tspringViewDisplay = new Panel();\n\t\tspringViewDisplay.setSizeFull();\n\t\troot.addComponent(springViewDisplay);\n\t\troot.setExpandRatio(springViewDisplay, 1.0f);\n\n\t\tgetNavigator().setErrorView(ErrorView.class);\n\t}\n\n\tprivate Button createNavigationButton(String caption, final String viewName) {\n\t\tButton button = new Button(caption);\n\t\tbutton.addStyleName(ValoTheme.BUTTON_SMALL);\n\t\n\t\tbutton.addClickListener(event -> getUI().getNavigator().navigateTo(viewName));\n\t\treturn button;\n\t}\n\n\t@Override\n\tpublic void showView(View view) {\n\t\tspringViewDisplay.setContent((Component) view);\n\t}\n\n}<\/pre>\n5. Demo Time<\/h2>\n
Run As Java Application<\/code>.[ulp id=’YBvYYzEYBUrADqmI’]<\/p>\n2018-02-25 21:28:50.970 INFO 12152 --- [ main] j.z.d.s.VaadinSpringDemoApplication : Starting VaadinSpringDemoApplication on SL2LS431841 with PID 12152 (C:\\MZheng_Java_workspace\\vaadin-spring-demo\\target\\classes started by shu.shan in C:\\MZheng_Java_workspace\\vaadin-spring-demo)\n2018-02-25 21:28:50.975 INFO 12152 --- [ main] j.z.d.s.VaadinSpringDemoApplication : No active profile set, falling back to default profiles: default\n2018-02-25 21:28:51.110 INFO 12152 --- [ main] ationConfigEmbeddedWebApplicationContext : Refreshing org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext@32464a14: startup date [Sun Feb 25 21:28:51 CST 2018]; root of context hierarchy\n2018-02-25 21:28:52.400 WARN 12152 --- [ main] o.s.c.a.ConfigurationClassPostProcessor : Cannot enhance @Configuration bean definition 'com.vaadin.spring.VaadinConfiguration' since its singleton instance has been created too early. The typical cause is a non-static @Bean method with a BeanDefinitionRegistryPostProcessor return type: Consider declaring such methods as 'static'.\n2018-02-25 21:28:53.959 INFO 12152 --- [ main] s.b.c.e.t.TomcatEmbeddedServletContainer : Tomcat initialized with port(s): 8080 (http)\n2018-02-25 21:28:53.985 INFO 12152 --- [ main] o.apache.catalina.core.StandardService : Starting service [Tomcat]\n2018-02-25 21:28:53.990 INFO 12152 --- [ main] org.apache.catalina.core.StandardEngine : Starting Servlet Engine: Apache Tomcat\/8.5.27\n2018-02-25 21:28:54.231 INFO 12152 --- [ost-startStop-1] o.a.c.c.C.[Tomcat].[localhost].[\/] : Initializing Spring embedded WebApplicationContext\n2018-02-25 21:28:54.231 INFO 12152 --- [ost-startStop-1] o.s.web.context.ContextLoader : Root WebApplicationContext: initialization completed in 3127 ms\n2018-02-25 21:28:54.471 INFO 12152 --- [ost-startStop-1] c.v.s.b.i.VaadinServletConfiguration : Registering Vaadin servlet\n2018-02-25 21:28:54.472 INFO 12152 --- [ost-startStop-1] c.v.s.b.i.VaadinServletConfiguration : Servlet will be mapped to URLs [\/vaadinServlet\/*, \/VAADIN\/*]\n2018-02-25 21:28:54.505 INFO 12152 --- [ost-startStop-1] c.v.s.b.i.VaadinServletConfiguration : Setting servlet init parameters\n2018-02-25 21:28:54.506 INFO 12152 --- [ost-startStop-1] c.v.s.b.i.VaadinServletConfiguration : Set servlet init parameter [productionMode] = [false]\n2018-02-25 21:28:54.506 INFO 12152 --- [ost-startStop-1] c.v.s.b.i.VaadinServletConfiguration : Set servlet init parameter [resourceCacheTime] = [3600]\n2018-02-25 21:28:54.506 INFO 12152 --- [ost-startStop-1] c.v.s.b.i.VaadinServletConfiguration : Set servlet init parameter [heartbeatInterval] = [300]\n2018-02-25 21:28:54.506 INFO 12152 --- [ost-startStop-1] c.v.s.b.i.VaadinServletConfiguration : Set servlet init parameter [closeIdleSessions] = [false]\n2018-02-25 21:28:54.642 INFO 12152 --- [ost-startStop-1] o.s.b.w.servlet.ServletRegistrationBean : Mapping servlet: 'dispatcherServlet' to [\/]\n2018-02-25 21:28:54.645 INFO 12152 --- [ost-startStop-1] o.s.b.w.servlet.ServletRegistrationBean : Mapping servlet: 'springVaadinServlet' to [\/vaadinServlet\/*, \/VAADIN\/*]\n2018-02-25 21:28:54.650 INFO 12152 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean : Mapping filter: 'characterEncodingFilter' to: [\/*]\n2018-02-25 21:28:54.653 INFO 12152 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean : Mapping filter: 'hiddenHttpMethodFilter' to: [\/*]\n2018-02-25 21:28:54.653 INFO 12152 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean : Mapping filter: 'httpPutFormContentFilter' to: [\/*]\n2018-02-25 21:28:54.653 INFO 12152 --- [ost-startStop-1] o.s.b.w.servlet.FilterRegistrationBean : Mapping filter: 'requestContextFilter' to: [\/*]\n2018-02-25 21:28:55.274 INFO 12152 --- [ main] s.w.s.m.m.a.RequestMappingHandlerAdapter : Looking for @ControllerAdvice: org.springframework.boot.context.embedded.AnnotationConfigEmbeddedWebApplicationContext@32464a14: startup date [Sun Feb 25 21:28:51 CST 2018]; root of context hierarchy\n2018-02-25 21:28:55.411 INFO 12152 --- [ main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped \"{[\/error]}\" onto public org.springframework.http.ResponseEntity<java.util.Map> org.springframework.boot.autoconfigure.web.BasicErrorController.error(javax.servlet.http.HttpServletRequest)\n2018-02-25 21:28:55.413 INFO 12152 --- [ main] s.w.s.m.m.a.RequestMappingHandlerMapping : Mapped \"{[\/error],produces=}\" onto public org.springframework.web.servlet.ModelAndView org.springframework.boot.autoconfigure.web.BasicErrorController.errorHtml(javax.servlet.http.HttpServletRequest,javax.servlet.http.HttpServletResponse)\n2018-02-25 21:28:55.480 INFO 12152 --- [ main] o.s.w.s.handler.SimpleUrlHandlerMapping : Mapped URL path [\/webjars\/**] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]\n2018-02-25 21:28:55.481 INFO 12152 --- [ main] o.s.w.s.handler.SimpleUrlHandlerMapping : Mapped URL path [\/**] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]\n2018-02-25 21:28:55.621 INFO 12152 --- [ main] o.s.w.s.handler.SimpleUrlHandlerMapping : Mapped URL path [\/**\/favicon.ico] onto handler of type [class org.springframework.web.servlet.resource.ResourceHttpRequestHandler]\n2018-02-25 21:28:55.681 INFO 12152 --- [ main] c.v.s.b.i.VaadinServletConfiguration : Checking the application context for Vaadin UI mappings\n2018-02-25 21:28:55.690 INFO 12152 --- [ main] c.v.s.b.i.VaadinServletConfiguration : Registering Vaadin servlet of type [com.vaadin.spring.server.SpringVaadinServlet]\n2018-02-25 21:28:55.703 INFO 12152 --- [ main] c.v.s.b.i.VaadinServletConfiguration : Forwarding @SpringUI URLs from {\/vaadin-spring-demo=org.springframework.web.servlet.mvc.ServletForwardingController@22db8f4, \/vaadin-spring-demo\/=org.springframework.web.servlet.mvc.ServletForwardingController@22db8f4}\n2018-02-25 21:28:55.704 INFO 12152 --- [ main] o.s.w.s.handler.SimpleUrlHandlerMapping : Mapped URL path [\/vaadin-spring-demo] onto handler of type [class org.springframework.web.servlet.mvc.ServletForwardingController]\n2018-02-25 21:28:55.705 INFO 12152 --- [ main] o.s.w.s.handler.SimpleUrlHandlerMapping : Mapped URL path [\/vaadin-spring-demo\/] onto handler of type [class org.springframework.web.servlet.mvc.ServletForwardingController]\n2018-02-25 21:28:56.099 INFO 12152 --- [ main] o.s.j.e.a.AnnotationMBeanExporter : Registering beans for JMX exposure on startup\n2018-02-25 21:28:56.220 INFO 12152 --- [ main] s.b.c.e.t.TomcatEmbeddedServletContainer : Tomcat started on port(s): 8080 (http)\n2018-02-25 21:28:56.234 INFO 12152 --- [ main] j.z.d.s.VaadinSpringDemoApplication : Started VaadinSpringDemoApplication in 5.866 seconds (JVM running for 6.483)\n2018-02-25 21:28:56.324 WARN 12152 --- [nio-8080-exec-3] c.v.s.DefaultDeploymentConfiguration :<\/pre>\nhttp:\/\/localhost:8080\/vaadin-spring-demo<\/code>. It will display “Welcome to Vaadin-Spring Demo” from the DefaultView<\/code>.<\/p>\n![\"\"](\"http:\/\/examples.javacodegeeks.com\/wp-content\/uploads\/2018\/02\/Figure-2-SPA-default-view.jpg\")
<\/a>DemoUIScopedBean<\/code>.<\/p>\n![\"\"](\"http:\/\/examples.javacodegeeks.com\/wp-content\/uploads\/2018\/02\/Figure-3-SPA-UI_scoped-view.jpg\")
<\/a>DemoViewScopeBean<\/code>.<\/p>\n![\"\"](\"http:\/\/examples.javacodegeeks.com\/wp-content\/uploads\/2018\/02\/Figure-4-SPA-View_scoped-view.jpg\")
<\/a>@UIScope<\/code> bean has same instance when clicking the button back and forth. But the @ViewScope<\/code> bean has a new instance for each click.<\/p>\n6. Summary<\/h2>\n
7. Download the Source Code<\/h2>\n