Java 尝试使用jersey 2.7和spring 3加载spring应用程序上下文时获取空指针异常

我正在使用Jersey 2.7和Spring以及Hibernate。我在applicationContext.xml中声明了@autowiredbean，得到了一个空指针异常

<?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:aop="http://www.springframework.org/schema/aop"
    xmlns:context="http://www.springframework.org/schema/context"
    xmlns:jee="http://www.springframework.org/schema/jee" xmlns:lang="http://www.springframework.org/schema/lang"
    xmlns:p="http://www.springframework.org/schema/p" xmlns:tx="http://www.springframework.org/schema/tx"
    xmlns:util="http://www.springframework.org/schema/util"
    xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop.xsd
        http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd
        http://www.springframework.org/schema/jee http://www.springframework.org/schema/jee/spring-jee.xsd
        http://www.springframework.org/schema/lang http://www.springframework.org/schema/lang/spring-lang.xsd
        http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx.xsd
        http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util.xsd">

    <context:annotation-config />
    <context:component-scan base-package="com.cws.rest" />
    <context:component-scan base-package="com.cws.dao" />

    <bean id="caseParticipantsDAO" class="com.cws.dao.impl.CaseParticipantsDAOImpl" />
</beans>

My web.xml

<?xml version="1.0" encoding="UTF-8"?>
<web-app id="WebApp_ID" version="2.5"
    xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd">
    <display-name>CWS2020POC</display-name>

    <context-param>
        <param-name>contextConfigLocation</param-name>
        <param-value>classpath:applicationContext.xml</param-value>
    </context-param>
    <listener>
        <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
    </listener>


    <filter>
        <filter-name>CorsFilter</filter-name>
        <filter-class>com.cws.filters.CorsFilter</filter-class>
    </filter>
    <filter-mapping>
        <filter-name>CorsFilter</filter-name>
        <url-pattern>/*</url-pattern>
    </filter-mapping>

    <servlet>
        <servlet-name>RESTService</servlet-name>
        <servlet-class>org.glassfish.jersey.servlet.ServletContainer</servlet-class>
        <init-param>
            <param-name>jersey.config.server.provider.packages</param-name>
            <param-value>com.cws.rest</param-value>
        </init-param>
        <init-param>
            <param-name>com.sun.jersey.api.json.POJOMappingFeature</param-name>
            <param-value>true</param-value>
        </init-param>
        <load-on-startup>1</load-on-startup>
    </servlet>
    <servlet-mapping>
        <servlet-name>RESTService</servlet-name>
        <url-pattern>/rest/*</url-pattern>
    </servlet-mapping>
</web-app>

我在这一行得到一个空指针

return caseParticipantsDAO.getCaseClients(caseId);

其中caseParticipantsDAO为空

如果我手动尝试使用以下代码加载applicationContext.xml

ApplicationContext configFile = new ClassPathXmlApplicationContext(
         "applicationContext.xml");
         CaseParticipantsDAO caseParticipantsDAO = (CaseParticipantsDAO)
         configFile
         .getBean("caseParticipantsDAO");

---

一切正常。但是我需要通过web.xml加载applicationContext.xml，并希望在整个应用程序中保持上下文，以便在需要时自动连接bean。

您应该尝试包括maven-spring3。这应该考虑到jersey和spring的集成

<!-- https://mvnrepository.com/artifact/com.sun.jersey.contribs/jersey-spring -->
<dependency>
    <groupId>com.sun.jersey.contribs</groupId>
    <artifactId>jersey-spring</artifactId>
    <version>1.19.4</version>
</dependency>

---

您是如何创建CaseParticipantsService的？可能与我没有专门创建CaseParticipantsService类的实例重复。它是一个RESTful web服务，当我点击url调用此特定服务时会调用它。我是否也需要单独加载服务类？我尝试使用SpringBeanAuthoringSupport扩展CaseParticipants服务，方法如下：公共类CaseParticipants服务扩展SpringBeanAuthoringSupport，效果如预期。它不再提供空指针异常。但我不确定这是否正确。请注意，您使用的是Jersey，Jersey控制的是bean，而不是spring，尽管有@Component注释，因此@Autowired无法工作。你必须确保你有正确的Jersey/Spring集成，这是你目前没有的。看见

<!-- https://mvnrepository.com/artifact/com.sun.jersey.contribs/jersey-spring -->
<dependency>
    <groupId>com.sun.jersey.contribs</groupId>
    <artifactId>jersey-spring</artifactId>
    <version>1.19.4</version>
</dependency>