java - 使用@ResponseBody 返回对象时的响应代码 500-6ren

java - 使用@ResponseBody 返回对象时的响应代码 500

转载作者：行者123 更新时间：2023-11-29 05:21:00

我是 spring Restful 编程的新手需要使用 Controller 方法作为休息服务，所以我试图以 JSON 格式返回一个对象，但由于某种原因我得到的响应代码为500，日志文件中没有错误和异常。

但是如果我的返回类型是一个字符串而不是一个对象，它就成功地工作了

我正在使用 jackson 依赖项，我正在上下文文件中进行配置，并假设将对象转换为 json 格式并在使用 @ResponseBody 注释时放入响应正文

//响应码500如果我返回一个对象

@RequestMapping(value = "/donorSummary", method = RequestMethod.GET,produces = "application/json")
  @PreAuthorize("hasRole('"+PermissionConstants.VIEW_DONOR+"')")
  public @ResponseBody Donor donorSummaryGenerator(HttpServletRequest request, Model model,HttpServletResponse response,
      @RequestParam(value = "donorId", required = false) Long donorId) {

       //some code here

        return donorObject; 

     }

//如果我返回一个字符串，工作

 @RequestMapping(value = "/donorSummary", method = RequestMethod.GET,produces = "application/json")
      @PreAuthorize("hasRole('"+PermissionConstants.VIEW_DONOR+"')")
      public @ResponseBody StringdonorSummaryGenerator(HttpServletRequest request, Model model,HttpServletResponse response,
          @RequestParam(value = "donorId", required = false) Long donorId) {

            //some oode here 

            return donorObject.toString(); 

         }

应用上下文文件

<?xml version="1.0" encoding="UTF-8"?>

<beans xmlns="http://www.springframework.org/schema/beans"
  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xmlns:context="http://www.springframework.org/schema/context"
  xmlns:mvc="http://www.springframework.org/schema/mvc"
  xmlns:p="http://www.springframework.org/schema/p"
  xmlns:tx="http://www.springframework.org/schema/tx"
  xmlns:task="http://www.springframework.org/schema/task"
  xmlns:int="http://www.springframework.org/schema/integration"
  xmlns:int-mail="http://www.springframework.org/schema/integration/mail"
  xmlns:security="http://www.springframework.org/schema/security"
  xmlns:util="http://www.springframework.org/schema/util"
  xsi:schemaLocation="http://www.springframework.org/schema/beans
        http://www.springframework.org/schema/beans/spring-beans-3.1.xsd
        http://www.springframework.org/schema/security
        http://www.springframework.org/schema/security/spring-security-3.1.xsd
        http://www.springframework.org/schema/mvc
        http://www.springframework.org/schema/mvc/spring-mvc-3.1.xsd
        http://www.springframework.org/schema/integration
        http://www.springframework.org/schema/integration/spring-integration-2.2.xsd
        http://www.springframework.org/schema/integration/mail
        http://www.springframework.org/schema/integration/mail/spring-integration-mail-2.2.xsd
        http://www.springframework.org/schema/util
        http://www.springframework.org/schema/util/spring-util-2.0.xsd
        http://www.springframework.org/schema/context
        http://www.springframework.org/schema/context/spring-context-3.0.xsd
        http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-2.5.xsd
        http://www.springframework.org/schema/task http://www.springframework.org/schema/task/spring-task-3.1.xsd">

  <!-- Annotations like PreAuthorize, needed here and not in security-v2v-servlet.xml
       as this is the MVC configuration dealing with URLs??? -->
  <security:global-method-security pre-post-annotations="enabled" />
  <context:property-placeholder location="classpath:database.properties" />

  <!-- Configures the @Controller programming model -->
  <mvc:annotation-driven />

  <context:component-scan base-package="controller" />
  <context:component-scan base-package="repository" />
  <context:component-scan base-package="model" />
  <context:component-scan base-package="viewmodel" />
  <context:component-scan base-package="tasks" />
  <context:component-scan base-package="utils" />
  <context:component-scan base-package="security" />

  <bean id="messageSource"
    class="org.springframework.context.support.ReloadableResourceBundleMessageSource">
    <property name="basenames">
      <list>
        <value>classpath:messages</value>
      </list>
    </property>
  </bean>

  <bean id="viewResolver"
    class="org.springframework.web.servlet.view.UrlBasedViewResolver">
    <property name="viewClass"
      value="org.springframework.web.servlet.view.JstlView" />
    <property name="prefix" value="/WEB-INF/jsp/" />
    <property name="suffix" value=".jsp" />
  </bean>

  <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource"
          destroy-method="close">
        <property name="driverClass" value="${database.driver}" />
        <property name="jdbcUrl" value="${database.url}" />
        <property name="user" value="${database.user}" />
        <property name="password" value="${database.password}" /> 

        <!-- these are C3P0 properties -->
        <property name="acquireIncrement" value="${database.acquireIncrement}" />
        <property name="minPoolSize" value="${database.minPoolSize}" />
        <property name="maxPoolSize" value="${database.maxPoolSize}" />
        <property name="maxIdleTime" value="${database.maxIdleTime}" />
  </bean>

  <!-- persistence unit name comes from persistence.xml -->
  <bean id="entityManagerFactory"
    class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean"
    p:dataSource-ref="dataSource" p:persistenceUnitName="v2v">
    <property name="jpaProperties">
      <props>
        <prop key="hibernate.dialect">org.hibernate.dialect.MySQL5InnoDBDialect</prop>
        <prop key="hibernate.show_sql">true</prop>
        <prop key="hibernate.hbm2ddl.auto">none</prop>
        <prop key="javax.persistence.validation.mode">none</prop>
      </props>
    </property>
  </bean>

  <bean id="transactionManager" class="org.springframework.orm.jpa.JpaTransactionManager">
    <property name="entityManagerFactory" ref="entityManagerFactory" />
  </bean>

  <bean id="applicationContextProvider" class="repository.events.ApplicationContextProvider"></bean>
  <bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver">
  </bean>

  <mvc:interceptors>
    <bean id="loggingInterceptor" class="interceptor.LoggingInterceptor" />
  </mvc:interceptors>

  <tx:annotation-driven transaction-manager="transactionManager" />

  <task:executor id="executor" pool-size="5"/>
  <task:scheduler id="scheduler" pool-size="5"/>
  <task:annotation-driven scheduler="scheduler" executor="executor"/>

    <property name="javaMailProperties">
      <props>
        <prop key="mail.smtp.starttls.enable">true</prop>
          <prop key="mail.smtp.auth">true</prop>
       </props>
    </property>
  </bean>

  <int:service-activator input-channel="receiveEmailChannel"
                         ref="emailReceiverService"
                         method="receive" />

  <int-mail:inbound-channel-adapter id="imapAdapter"
    store-uri="imaps://${imap.username}:${imap.password}@imap.googlemail.com:993/INBOX"
    java-mail-properties="javaMailProperties"
    channel="receiveEmailChannel"
    should-delete-messages="false"
    should-mark-messages-as-read="false"
    auto-startup="true"
    >



</beans>

pom.xml

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <groupId>bsis</groupId>
    <name>BSIS</name>
    <description>(BSIS)</description>
    <artifactId>bsis</artifactId>
    <version>0.1</version>
    <packaging>war</packaging>

    <properties>
        <webapp.name>bsis</webapp.name>
        <cxf-version>2.2.10</cxf-version>
        <liquibase.propertyFile>liquibase/liquibase.properties</liquibase.propertyFile>
    </properties>

    <build>
        <finalName>${webapp.name}</finalName>
        <sourceDirectory>src</sourceDirectory>
        <testSourceDirectory>test</testSourceDirectory>

        <resources>
            <resource>
                <directory>src</directory>
                <excludes>
                    <exclude>**/*.java</exclude>
                </excludes>

            </resource>

        </resources>

        <testResources>
            <testResource>
                <directory>test</directory>
                <filtering>false</filtering>
                <includes>
                    <include>**/*.xml</include>
                    <include>**/*.sql</include>
                </includes>
            </testResource>
        </testResources>

        <plugins>

            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-surefire-plugin</artifactId>
                <version>2.12</version>
                <configuration>
                    <useFile>true</useFile>
                    <includes>
                        <include>**/*Tests.java</include>
                        <include>**/*Test.java</include>

                    </includes>
                    <excludes>
                        <exclude>**/Abstract*.java</exclude>
                    </excludes>
                    <reuseForks>false</reuseForks>
                    <forkCount>1</forkCount>
                    <junitArtifactName>junit:junit</junitArtifactName>
                    <parallel>methods</parallel>
                    <threadCount>10</threadCount>
                </configuration>
            </plugin>

            <plugin>
                <groupId>org.apache.tomcat.maven</groupId>
                <artifactId>tomcat7-maven-plugin</artifactId>
                <version>2.2</version>
                <configuration>
                    <server>tomcat</server>
                </configuration>
            </plugin>
            <plugin>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>3.0</version>
                <configuration>
                    <source>1.6</source>
                    <target>1.6</target>
                </configuration>
            </plugin>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-war-plugin</artifactId>
                <version>2.4</version>
                <configuration>
                    <webXml>${basedir}/war/WEB-INF/web.xml</webXml>
                    <warSourceDirectory>${basedir}/war</warSourceDirectory>
                </configuration>
            </plugin>
            <plugin>
                <groupId>org.liquibase</groupId>
                <artifactId>liquibase-maven-plugin</artifactId>
                <version>2.0.3</version>
                <configuration>
                    <propertyFile>liquibase/liquibase.properties</propertyFile>
                </configuration>
                <executions>
                    <execution>
                        <id></id>
                        <phase>verify</phase>
                        <goals>
                            <goal>update</goal>
                        </goals>
                    </execution>
                </executions>
            </plugin>

        </plugins>
    </build>
    <dependencies>
        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>servlet-api</artifactId>
            <version>2.4</version>
        </dependency>
        <dependency>
            <groupId>org.apache.tomcat</groupId>
            <artifactId>tomcat-coyote</artifactId>
            <version>7.0.5</version>
            <scope>provided</scope>
        </dependency>
        <dependency>
            <groupId>org.apache.tomcat</groupId>
            <artifactId>tomcat-api</artifactId>
            <version>7.0.5</version>
            <scope>provided</scope>
        </dependency>
        <dependency>
            <groupId>org.apache.tomcat</groupId>
            <artifactId>tomcat-servlet-api</artifactId>
            <version>7.0.5</version>
            <scope>provided</scope>
        </dependency>
        <dependency>
            <groupId>org.apache.tomcat</groupId>
            <artifactId>tomcat-juli</artifactId>
            <version>7.0.5</version>
            <scope>provided</scope>
        </dependency>
        <dependency>
            <groupId>org.apache.tomcat</groupId>
            <artifactId>tomcat-util</artifactId>
            <version>7.0.5</version>
            <scope>provided</scope>
        </dependency>
        <dependency>
            <groupId>org.apache.tomcat</groupId>
            <artifactId>tomcat-catalina</artifactId>
            <version>7.0.5</version>
            <scope>provided</scope>
        </dependency>
        <dependency>
            <groupId>org.hibernate</groupId>
            <artifactId>hibernate-c3p0</artifactId>
            <version>4.1.6.Final</version>
        </dependency>
        <dependency>
            <groupId>org.hibernate.common</groupId>
            <artifactId>hibernate-commons-annotations</artifactId>
            <version>4.0.1.Final</version>
        </dependency>
        <dependency>
            <groupId>org.hibernate</groupId>
            <artifactId>hibernate-core</artifactId>
            <version>4.1.6.Final</version>
        </dependency>
        <dependency>
            <groupId>org.hibernate</groupId>
            <artifactId>hibernate-entitymanager</artifactId>
            <version>4.1.6.Final</version>
        </dependency>
        <dependency>
            <groupId>org.hibernate</groupId>
            <artifactId>hibernate-envers</artifactId>
            <version>4.1.6.Final</version>
        </dependency>
        <dependency>
            <groupId>org.hibernate.javax.persistence</groupId>
            <artifactId>hibernate-jpa-2.0-api</artifactId>
            <version>1.0.1.Final</version>
        </dependency>
        <dependency>
            <groupId>org.hibernate</groupId>
            <artifactId>hibernate-validator</artifactId>
            <version>4.3.0.Final</version>
        </dependency>
        <dependency>
            <groupId>org.apache.httpcomponents</groupId>
            <artifactId>httpclient</artifactId>
            <version>4.2.3</version>
        </dependency>
        <dependency>
            <groupId>joda-time</groupId>
            <artifactId>joda-time</artifactId>
            <version>2.1</version>
        </dependency>
        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>jstl</artifactId>
            <version>1.2</version>
        </dependency>
        <dependency>
            <groupId>log4j</groupId>
            <artifactId>log4j</artifactId>
            <version>1.2.17</version>
        </dependency>
        <dependency>
            <groupId>com.mchange</groupId>
            <artifactId>mchange-commons-java</artifactId>
            <version>0.2.3.3</version>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>5.1.22</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-aop</artifactId>
            <version>3.1.2.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-aspects</artifactId>
            <version>3.1.2.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-beans</artifactId>
            <version>3.1.2.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context</artifactId>
            <version>3.1.2.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context-support</artifactId>
            <version>3.1.2.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-core</artifactId>
            <version>3.1.2.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-expression</artifactId>
            <version>3.1.2.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-instrument</artifactId>
            <version>3.1.2.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-instrument-tomcat</artifactId>
            <version>3.1.2.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-jdbc</artifactId>
            <version>3.1.2.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-jms</artifactId>
            <version>3.1.2.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-orm</artifactId>
            <version>3.1.2.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-oxm</artifactId>
            <version>3.1.2.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-test</artifactId>
            <version>3.2.1.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-tx</artifactId>
            <version>3.1.2.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-web</artifactId>
            <version>3.1.2.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-webmvc</artifactId>
            <version>3.1.2.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.slf4j</groupId>
            <artifactId>slf4j-api</artifactId>
            <version>1.7.2</version>
        </dependency>
        <dependency>
            <groupId>org.slf4j</groupId>
            <artifactId>slf4j-simple</artifactId>
            <version>1.7.2</version>
        </dependency>
        <dependency>
            <groupId>javax.validation</groupId>
            <artifactId>validation-api</artifactId>
            <version>1.1.0.Final</version>
        </dependency>
        <dependency>
            <groupId>aopalliance</groupId>
            <artifactId>aopalliance</artifactId>
            <version>1.0</version>
        </dependency>
        <dependency>
            <groupId>antlr</groupId>
            <artifactId>antlr</artifactId>
            <version>2.7.7</version>
        </dependency>
        <dependency>
            <groupId>c3p0</groupId>
            <artifactId>c3p0</artifactId>
            <version>0.9.1.2</version>
        </dependency>
        <dependency>
            <groupId>cglib</groupId>
            <artifactId>cglib-nodep</artifactId>
            <version>2.2.2</version>
        </dependency>
        <dependency>
            <groupId>commons-beanutils</groupId>
            <artifactId>commons-beanutils</artifactId>
            <version>1.8.3</version>
        </dependency>
        <dependency>
            <groupId>commons-collections</groupId>
            <artifactId>commons-collections</artifactId>
            <version>3.2.1</version>
        </dependency>
        <dependency>
            <groupId>org.apache.commons</groupId>
            <artifactId>commons-lang3</artifactId>
            <version>3.1</version>
        </dependency>
        <dependency>
            <groupId>commons-logging</groupId>
            <artifactId>commons-logging</artifactId>
            <version>1.1.1</version>
        </dependency>
        <dependency>
            <groupId>commons-logging</groupId>
            <artifactId>commons-logging-adapters</artifactId>
            <version>1.1</version>
        </dependency>
        <dependency>
            <groupId>commons-logging</groupId>
            <artifactId>commons-logging-api</artifactId>
            <version>1.1</version>
        </dependency>
         //Jackson dependencies
        <dependency>
            <groupId>org.codehaus.jackson</groupId>
            <artifactId>jackson-mapper-asl</artifactId>
            <version>1.9.12</version>
        </dependency>
        <dependency>
            <groupId>org.codehaus.jackson</groupId>
            <artifactId>jackson-core-asl</artifactId>
            <version>1.9.12</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.security</groupId>
            <artifactId>spring-security-web</artifactId>
            <version>3.1.2.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.security</groupId>
            <artifactId>spring-security-acl</artifactId>
            <version>3.1.2.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.security</groupId>
            <artifactId>spring-security-aspects</artifactId>
            <version>3.1.2.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.security</groupId>
            <artifactId>spring-security-config</artifactId>
            <version>3.1.2.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.security</groupId>
            <artifactId>spring-security-core</artifactId>
            <version>3.1.2.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.integration</groupId>
            <artifactId>spring-integration-core</artifactId>
            <version>2.2.3.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.integration</groupId>
            <artifactId>spring-integration-mail</artifactId>
            <version>2.2.3.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>javax.mail</groupId>
            <artifactId>mail</artifactId>
            <version>1.4.7</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.security</groupId>
            <artifactId>spring-security-taglibs</artifactId>
            <version>3.1.4.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.liquibase</groupId>
            <artifactId>liquibase-core</artifactId>
            <version>2.0.3</version>
        </dependency>   
        <dependency>    
            <groupId>turbine</groupId>  
            <artifactId>turbine</artifactId>    
            <version>2.1</version>  
        </dependency>
        <dependency>    
            <groupId>net.sf.opencsv</groupId>   
            <artifactId>opencsv</artifactId>
            <version>2.0</version>
        </dependency>
        <dependency>
            <groupId>commons-fileupload</groupId>
            <artifactId>commons-fileupload</artifactId>
            <version>1.2</version>
        </dependency>
        <dependency>
            <groupId>org.apache.commons</groupId>
            <artifactId>commons-io</artifactId>
            <version>1.3.2</version>
        </dependency>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit-dep</artifactId>
            <version>4.8.2</version>
        </dependency>
        <dependency>
            <groupId>org.mockito</groupId>
            <artifactId>mockito-core</artifactId>
            <version>1.9.5</version>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>com.github.springtestdbunit</groupId>
            <artifactId>spring-test-dbunit</artifactId>
            <version>1.0.0</version>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>org.dbunit</groupId>
            <artifactId>dbunit</artifactId>
            <version>2.4.9</version>
            <scope>test</scope>
            <exclusions>
                <exclusion>
                    <artifactId>junit</artifactId>
                    <groupId>junit</groupId>
                </exclusion>
            </exclusions>
        </dependency>
        <dependency>
            <groupId>com.jolbox</groupId>
            <artifactId>bonecp</artifactId>
            <version>0.8.0.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.hsqldb</groupId>
            <artifactId>hsqldb</artifactId>
            <version>2.2.8</version>
        </dependency>
        <dependency>
            <groupId>org.hsqldb</groupId>
            <artifactId>sqltool</artifactId>
            <version>2.0.0</version>
        </dependency>
        <!-- 
        <dependency>
            <groupId>org.testng</groupId>
            <artifactId>testng</artifactId>
            <version>6.8</version>
            <scope>test</scope>
        </dependency>
        -->
    </dependencies>
</project>

最佳答案

Spring MVC 使用消息转换器(HttpMessageConverter 接口(interface)的实现)将数据与 JSON(和其他格式，例如 XML)相互转换。

<mvc:annotation-driven /> Spring 配置中的标记注册 JSON 消息转换器(以及它正在做的其他事情)。要开始在 Web 服务中使用 JSON，您唯一需要做的另一件事是将 Jackson 库放在您的类路径中(您说您已经拥有它们):

<dependency>
    <groupId>com.fasterxml.jackson.core</groupId>
    <artifactId>jackson-core</artifactId>
    <version>2.3.0</version>
</dependency>
<dependency>
    <groupId>com.fasterxml.jackson.core</groupId>
    <artifactId>jackson-databind</artifactId>
    <version>2.3.0</version>
</dependency>

现在，您还可以为 JSON 消息转换器进行一些手动配置:

<bean class="org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter">
    <property name="messageConverters">
        <list>
            <ref bean="jsonMessageConverter"/>
        </list>
    </property>
</bean>

<bean id="jsonMessageConverter" class="org.springframework.http.converter.json.MappingJackson2HttpMessageConverter">
</bean>

这可能是不必要的。尝试将其删除。 <mvc:annotation-driven />标记是注册 JSON 消息转换器所需的全部内容。

关于java - 使用@ResponseBody 返回对象时的响应代码 500，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/24766728/

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