All geek questions in one place

Webservice with Gson in Spring

I would like to use Gson for web services in spring 4. I followed the steps in this tutorial.

SocialGraphUI-servlet.xml

<?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:context="http://www.springframework.org/schema/context" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:mvc="http://www.springframework.org/schema/mvc" xsi:schemaLocation=" http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-4.0.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-4.0.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-4.0.xsd"> <context:component-scan base-package="socialgraphui.controller" /> <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver"> <property name="prefix" value="/WEB-INF/jsp/" /> <property name="suffix" value=".jsp" /> </bean> <mvc:resources mapping="/scripts/**" location="/scripts/" /> <mvc:resources mapping="/styles/**" location="/styles/" /> <mvc:annotation-driven /> <mvc:annotation-driven> <mvc:message-converters> <bean class="com.example.converter.GsonMessageConverter" /> <bean class="org.springframework.http.converter.json.MappingJacksonHttpMessageConverter"> <property name="prefixJson" value="true" /> </bean> </mvc:message-converters> </mvc:annotation-driven> </beans>

GsonMessageConverter.java

 public class GsonMessageConverter extends AbstractHttpMessageConverter<Object> implements GenericHttpMessageConverter<Object> { public static final Charset DEFAULT_CHARSET = Charset.forName("UTF-8"); private Gson _gson; private Type _type = null; private boolean _prefixJson = false; /** * Construct a new {@code GsonMessageConverter} with a default * {@link Gson#Gson() Gson}. */ public GsonMessageConverter() { this(new Gson()); } /** * Construct a new {@code GsonMessageConverter}. * * @param serializeNulls * true to generate json for null values */ public GsonMessageConverter(boolean serializeNulls) { this(serializeNulls ? new GsonBuilder().serializeNulls().create() : new Gson()); } /** * Construct a new {@code GsonMessageConverter}. * * @param gson * a customized {@link Gson#Gson() Gson} */ public GsonMessageConverter(Gson gson) { super(new MediaType("application", "json", DEFAULT_CHARSET)); setGson(gson); } /** * Sets the {@code Gson} for this view. If not set, a default * {@link Gson#Gson() Gson} is used. * <p> * Setting a custom-configured {@code Gson} is one way to take further * control of the JSON serialization process. * * @throws IllegalArgumentException * if gson is null */ public void setGson(Gson gson) { Assert.notNull(gson, "'gson' must not be null"); _gson = gson; } public void setType(Type type) { this._type = type; } public Type getType() { return _type; } /** * Indicates whether the JSON output by this view should be prefixed with * "{} &&". Default is false. * <p> * Prefixing the JSON string in this manner is used to help prevent JSON * Hijacking. The prefix renders the string syntactically invalid as a * script so that it cannot be hijacked. This prefix does not affect the * evaluation of JSON, but if JSON validation is performed on the string, * the prefix would need to be ignored. */ public void setPrefixJson(boolean prefixJson) { this._prefixJson = prefixJson; } @Override public boolean canRead(Class<?> clazz, MediaType mediaType) { return canRead(mediaType); } @Override public boolean canRead(Type type, Class<?> contextClass, MediaType mediaType) { return canRead(mediaType); } @Override public boolean canWrite(Class<?> clazz, MediaType mediaType) { return canWrite(mediaType); } @Override protected boolean supports(Class<?> clazz) { // should not be called, since we override canRead/Write instead throw new UnsupportedOperationException(); } /** * Generic types will be processed here. */ @Override public Object read(Type type, Class<?> contextClass, HttpInputMessage inputMessage) throws HttpMessageNotReadableException, IOException { setType(type); return readInternal(null, inputMessage); } @Override protected Object readInternal(Class<?> clazz, HttpInputMessage inputMessage) throws IOException, HttpMessageNotReadableException { Reader json = new InputStreamReader(inputMessage.getBody(), getCharset(inputMessage.getHeaders())); try { Type typeOfT = getType(); if (typeOfT != null) { return _gson.fromJson(json, typeOfT); } else { return _gson.fromJson(json, clazz); } } catch (JsonSyntaxException ex) { throw new HttpMessageNotReadableException("Could not read JSON: " + ex.getMessage(), ex); } catch (JsonIOException ex) { throw new HttpMessageNotReadableException("Could not read JSON: " + ex.getMessage(), ex); } catch (JsonParseException ex) { throw new HttpMessageNotReadableException("Could not read JSON: " + ex.getMessage(), ex); } finally { setType(null); } } @Override protected void writeInternal(Object o, HttpOutputMessage outputMessage) throws IOException, HttpMessageNotWritableException { OutputStreamWriter writer = new OutputStreamWriter( outputMessage.getBody(), getCharset(outputMessage.getHeaders())); try { if (this._prefixJson) { writer.append("{} && "); } Type typeOfSrc = getType(); if (typeOfSrc != null) { _gson.toJson(o, typeOfSrc, writer); } else { _gson.toJson(o, writer); } writer.close(); } catch (JsonIOException ex) { throw new HttpMessageNotWritableException("Could not write JSON: " + ex.getMessage(), ex); } } // helpers private Charset getCharset(HttpHeaders headers) { if (headers != null && headers.getContentType() != null && headers.getContentType().getCharSet() != null) { return headers.getContentType().getCharSet(); } return DEFAULT_CHARSET; } }

Get the request method in SocialGraphUI.java . There is an object test and an allNodes method that returns a list of objects of the Node class, and allEdges returns a list of objects of the Edge class.

  @RequestMapping(value = "/", method = RequestMethod.GET) public String getNodesAndEdges(ModelMap model) { model.addAttribute("nodes", test.allNodes); model.addAttribute("edges", test.allEdges); return "index"; }

I get these error messages:

  type Exception report message Servlet.init() for servlet SocialGraphUI threw exception description The server encountered an internal error that prevented it from fulfilling this request. exception javax.servlet.ServletException: Servlet.init() for servlet SocialGraphUI threw exception org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502) org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:99) org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:953) org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408) org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1023) org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:589) org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:310) java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) java.lang.Thread.run(Thread.java:745) root cause org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'mvcUriComponentsContributor': Cannot create inner bean '(inner bean)#1043cc94' of type [org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter] while setting bean property 'handlerAdapter'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name '(inner bean)#1043cc94': Cannot create inner bean 'com.example.converter.GsonMessageConverter#0' of type [com.example.converter.GsonMessageConverter] while setting bean property 'messageConverters' with key [0]; nested exception is org.springframework.beans.factory.CannotLoadBeanClassException: Cannot find class [com.example.converter.GsonMessageConverter] for bean with name 'com.example.converter.GsonMessageConverter#0' defined in ServletContext resource [/WEB-INF/SocialGraphUI-servlet.xml]; nested exception is java.lang.ClassNotFoundException: com.example.converter.GsonMessageConverter org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveInnerBean(BeanDefinitionValueResolver.java:290) org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveValueIfNecessary(BeanDefinitionValueResolver.java:129) org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.applyPropertyValues(AbstractAutowireCapableBeanFactory.java:1456) org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1197) org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:537) org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:475) org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:302) org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:228) org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:298) org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:193) org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:684) org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:760) org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:482) org.springframework.web.servlet.FrameworkServlet.configureAndRefreshWebApplicationContext(FrameworkServlet.java:658) org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:624) org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:672) org.springframework.web.servlet.FrameworkServlet.initWebApplicationContext(FrameworkServlet.java:543) org.springframework.web.servlet.FrameworkServlet.initServletBean(FrameworkServlet.java:484) org.springframework.web.servlet.HttpServletBean.init(HttpServletBean.java:136) javax.servlet.GenericServlet.init(GenericServlet.java:160) org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502) org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:99) org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:953) org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408) org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1023) org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:589) org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:310) java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) java.lang.Thread.run(Thread.java:745) root cause org.springframework.beans.factory.BeanCreationException: Error creating bean with name '(inner bean)#1043cc94': Cannot create inner bean 'com.example.converter.GsonMessageConverter#0' of type [com.example.converter.GsonMessageConverter] while setting bean property 'messageConverters' with key [0]; nested exception is org.springframework.beans.factory.CannotLoadBeanClassException: Cannot find class [com.example.converter.GsonMessageConverter] for bean with name 'com.example.converter.GsonMessageConverter#0' defined in ServletContext resource [/WEB-INF/SocialGraphUI-servlet.xml]; nested exception is java.lang.ClassNotFoundException: com.example.converter.GsonMessageConverter org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveInnerBean(BeanDefinitionValueResolver.java:290) org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveValueIfNecessary(BeanDefinitionValueResolver.java:122) org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveManagedList(BeanDefinitionValueResolver.java:359) org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveValueIfNecessary(BeanDefinitionValueResolver.java:157) org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.applyPropertyValues(AbstractAutowireCapableBeanFactory.java:1456) org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1197) org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:537) org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:475) org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveInnerBean(BeanDefinitionValueResolver.java:276) org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveValueIfNecessary(BeanDefinitionValueResolver.java:129) org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.applyPropertyValues(AbstractAutowireCapableBeanFactory.java:1456) org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1197) org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:537) org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:475) org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:302) org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:228) org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:298) org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:193) org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:684) org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:760) org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:482) org.springframework.web.servlet.FrameworkServlet.configureAndRefreshWebApplicationContext(FrameworkServlet.java:658) org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:624) org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:672) org.springframework.web.servlet.FrameworkServlet.initWebApplicationContext(FrameworkServlet.java:543) org.springframework.web.servlet.FrameworkServlet.initServletBean(FrameworkServlet.java:484) org.springframework.web.servlet.HttpServletBean.init(HttpServletBean.java:136) javax.servlet.GenericServlet.init(GenericServlet.java:160) org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502) org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:99) org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:953) org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408) org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1023) org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:589) org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:310) java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) java.lang.Thread.run(Thread.java:745) root cause org.springframework.beans.factory.CannotLoadBeanClassException: Cannot find class [com.example.converter.GsonMessageConverter] for bean with name 'com.example.converter.GsonMessageConverter#0' defined in ServletContext resource [/WEB-INF/SocialGraphUI-servlet.xml]; nested exception is java.lang.ClassNotFoundException: com.example.converter.GsonMessageConverter org.springframework.beans.factory.support.AbstractBeanFactory.resolveBeanClass(AbstractBeanFactory.java:1325) org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:452) org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveInnerBean(BeanDefinitionValueResolver.java:276) org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveValueIfNecessary(BeanDefinitionValueResolver.java:122) org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveManagedList(BeanDefinitionValueResolver.java:359) org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveValueIfNecessary(BeanDefinitionValueResolver.java:157) org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.applyPropertyValues(AbstractAutowireCapableBeanFactory.java:1456) org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1197) org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:537) org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:475) org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveInnerBean(BeanDefinitionValueResolver.java:276) org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveValueIfNecessary(BeanDefinitionValueResolver.java:129) org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.applyPropertyValues(AbstractAutowireCapableBeanFactory.java:1456) org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1197) org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:537) org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:475) org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:302) org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:228) org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:298) org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:193) org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:684) org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:760) org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:482) org.springframework.web.servlet.FrameworkServlet.configureAndRefreshWebApplicationContext(FrameworkServlet.java:658) org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:624) org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:672) org.springframework.web.servlet.FrameworkServlet.initWebApplicationContext(FrameworkServlet.java:543) org.springframework.web.servlet.FrameworkServlet.initServletBean(FrameworkServlet.java:484) org.springframework.web.servlet.HttpServletBean.init(HttpServletBean.java:136) javax.servlet.GenericServlet.init(GenericServlet.java:160) org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502) org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:99) org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:953) org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408) org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1023) org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:589) org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:310) java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) java.lang.Thread.run(Thread.java:745) root cause java.lang.ClassNotFoundException: com.example.converter.GsonMessageConverter org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1714) org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1559) org.springframework.util.ClassUtils.forName(ClassUtils.java:247) org.springframework.beans.factory.support.AbstractBeanDefinition.resolveBeanClass(AbstractBeanDefinition.java:395) org.springframework.beans.factory.support.AbstractBeanFactory.doResolveBeanClass(AbstractBeanFactory.java:1346) org.springframework.beans.factory.support.AbstractBeanFactory.resolveBeanClass(AbstractBeanFactory.java:1317) org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:452) org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveInnerBean(BeanDefinitionValueResolver.java:276) org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveValueIfNecessary(BeanDefinitionValueResolver.java:122) org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveManagedList(BeanDefinitionValueResolver.java:359) org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveValueIfNecessary(BeanDefinitionValueResolver.java:157) org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.applyPropertyValues(AbstractAutowireCapableBeanFactory.java:1456) org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1197) org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:537) org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:475) org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveInnerBean(BeanDefinitionValueResolver.java:276) org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveValueIfNecessary(BeanDefinitionValueResolver.java:129) org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.applyPropertyValues(AbstractAutowireCapableBeanFactory.java:1456) org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1197) org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:537) org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:475) org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:302) org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:228) org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:298) org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:193) org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:684) org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:760) org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:482) org.springframework.web.servlet.FrameworkServlet.configureAndRefreshWebApplicationContext(FrameworkServlet.java:658) org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:624) org.springframework.web.servlet.FrameworkServlet.createWebApplicationContext(FrameworkServlet.java:672) org.springframework.web.servlet.FrameworkServlet.initWebApplicationContext(FrameworkServlet.java:543) org.springframework.web.servlet.FrameworkServlet.initServletBean(FrameworkServlet.java:484) org.springframework.web.servlet.HttpServletBean.init(HttpServletBean.java:136) javax.servlet.GenericServlet.init(GenericServlet.java:160) org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502) org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:99) org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:953) org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:408) org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1023) org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:589) org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:310) java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) java.lang.Thread.run(Thread.java:745) note The full stack trace of the root cause is available in the Apache Tomcat/7.0.42 logs.
+5
source share
1 answer

The main issue here might be the dual mvc:annotation-driven declaration mvc:annotation-driven .

But either way, Spring 4.1 has implemented Gson support to make it easier for you to achieve this:

 <?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:context="http://www.springframework.org/schema/context" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:mvc="http://www.springframework.org/schema/mvc" xsi:schemaLocation=" http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd"> <context:component-scan base-package="cz.ario.socialgraphui.controller" /> <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver"> <property name="prefix" value="/WEB-INF/jsp/" /> <property name="suffix" value=".jsp" /> </bean> <mvc:annotation-driven> <mvc:message-converters> <bean class="org.springframework.http.converter.json.GsonHttpMessageConverter" /> <!-- other HttpMessageConverters you need here --> <!-- Also: why adding Jackson MessageConverter? Gson should pick JSON serialization in this case --> </mvc:message-converters> </mvc:annotation-driven> <mvc:resources mapping="/scripts/**" location="/scripts/" /> <mvc:resources mapping="/styles/**" location="/styles/" /> </beans>

Same thing with the JavaConfig example:

 @Configuration @EnableWebMvc @ComponentScan("cz.ario.socialgraphui.controller") public class WebConfig extends WebMvcConfigurerAdapter { @Bean public InternalResourceViewResolver viewResolver() { InternalResourceViewResolver viewResolver = new InternalResourceViewResolver(); viewResolver.setPrefix("/WEB-INF/views/"); viewResolver.setSuffix(".jsp"); return viewResolver; } @Override public void configureMessageConverters(List<HttpMessageConverter<?>> converters) { converters.add(new GsonHttpMessageConverter()); // ... } @Override public void addResourceHandlers(ResourceHandlerRegistry registry) { registry.addResourceHandler("/scripts/**").addResourceLocations("/scripts/"); registry.addResourceHandler("/styles/**").addResourceLocations("/styles/"); } }

Note: you should (almost) never use XSD versions in XML configuration files - see this question for more details .

+7
source

Source: https://habr.com/ru/post/1208125/

More articles:


All Articles