java - 使用 Java 配置 Spring RESTFUL API webapp

Question

我在尝试使用 Spring Framework 和 Spring Security + Jersey 设置 RESTFUL API 时遇到了一些问题.

我可以部署 Jersey REST API 并成功请求资源，但是当我还实现了 Spring(框架 + Spring 安全性)时，事情就变得失控了。

我以前使用过旧的 Spring 版本，其中配置是使用 XML 文件进行的，但我想尝试并学习如何使用 配置它仅限 Java 注释。我遇到了麻烦，因为我无法通过 applicationContext.xml。我只是不想放置 XML 文件，我只想仅使用 Java 注释配置我的小型 Rest api Web 应用程序。

当我将 Spring Security 配置行添加到我的 web.xml 并尝试请求任何资源时，出现此错误:

未找到 WebApplicationContext:未注册 ContextLoaderListener 或 DispatcherServlet？

因此，我还将此代码段添加到了我的 web.xml 中:

    <listener>
        <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
    </listener>

然后，我为 Spring 创建了一个新的配置类，一个简单的:

@Configuration
@ComponentScan({
    "com.myapp.rest.api", 
    "com.myapp.business.services"
})
public class SpringApplicationConfig {

}

我再次重新启动我的 Tomcat 并尝试请求任何资源，然后它开始提示找不到 applicationContext.xml 文件，我没有提供，但我不知道为什么如果我有另一个带有 @Configuration 注释的类，它仍然试图找到它。如何在不使用 applicationContext.xml 的情况下配置 Spring？

注意:我知道 Spring MVC 和 Spring Boot，但我目前正在使用 Jersey > 并使用 Spring Framework 进行依赖注入(inject)，显然还使用 Spring Security 进行身份验证和安全性工作。

在我的web.xml下面:

<?xml version="1.0" encoding="UTF-8"?>
<!-- This web.xml file is not required when using Servlet 3.0 container, 
    see implementation details http://jersey.java.net/nonav/documentation/latest/jax-rs.html -->
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xmlns="http://java.sun.com/xml/ns/javaee"
    xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
    version="2.5">

    <servlet>
        <servlet-name>Jersey Web Application</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.myapp.rest.api</param-value>
        </init-param>
        <load-on-startup>1</load-on-startup>
    </servlet>
    <servlet-mapping>
        <servlet-name>Jersey Web Application</servlet-name>
        <url-pattern>/rest/*</url-pattern>
    </servlet-mapping>

    <!-- SPRING SECURITY -->
    <listener>
        <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
    </listener>
    <filter>
        <filter-name>springSecurityFilterChain</filter-name>
        <filter-class>org.springframework.web.filter.DelegatingFilterProxy</filter-class>
    </filter>

    <filter-mapping>
        <filter-name>springSecurityFilterChain</filter-name>
        <url-pattern>/*</url-pattern>
    </filter-mapping>
</web-app>

还有我的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/maven-v4_0_0.xsd">

    <modelVersion>4.0.0</modelVersion>

    <groupId>com.myapp</groupId>
    <artifactId>api</artifactId>
    <packaging>war</packaging>
    <version>0.0.1-SNAPSHOT</version>
    <name>api</name>

    <build>
        <finalName>my api</finalName>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>2.5.1</version>
                <inherited>true</inherited>
                <configuration>
                    <source>1.7</source>
                    <target>1.7</target>
                </configuration>
            </plugin>
        </plugins>
    </build>

    <dependencyManagement>
        <dependencies>
            <dependency>
                <groupId>org.glassfish.jersey</groupId>
                <artifactId>jersey-bom</artifactId>
                <version>${jersey.version}</version>
                <type>pom</type>
                <scope>import</scope>
            </dependency>
        </dependencies>
    </dependencyManagement>

    <dependencies>
        <!-- JERSEY (2) -->
        <dependency>
            <groupId>org.glassfish.jersey.containers</groupId>
            <artifactId>jersey-container-servlet-core</artifactId>
        </dependency>
        <!-- Soporte JSON -->
        <dependency>
            <groupId>org.glassfish.jersey.media</groupId>
            <artifactId>jersey-media-moxy</artifactId>
        </dependency>

    <!-- SPRING + SPRING SECURITY -->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context</artifactId>
            <version>${spring.version}</version>
        </dependency>

        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-context</artifactId>
            <version>${spring.version}</version>
        </dependency>

        <dependency>
            <groupId>org.springframework.security</groupId>
            <artifactId>spring-security-web</artifactId>
            <version>${spring-security.version}</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.security</groupId>
            <artifactId>spring-security-config</artifactId>
            <version>${spring-security.version}</version>
        </dependency>


        <!-- https://mvnrepository.com/artifact/javax.servlet/javax.servlet-api -->
        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>javax.servlet-api</artifactId>
            <version>${servlet-api.version}</version>
            <scope>provided</scope>
        </dependency>

        <!-- JACKSON - JSON -->
        <!-- https://mvnrepository.com/artifact/com.fasterxml.jackson.core/jackson-core -->
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-core</artifactId>
            <version>${jackson.version}</version>
        </dependency>
        <!-- https://mvnrepository.com/artifact/com.fasterxml.jackson.core/jackson-annotations -->
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-annotations</artifactId>
            <version>${jackson.version}</version>
        </dependency>
        <!-- https://mvnrepository.com/artifact/com.fasterxml.jackson.core/jackson-databind -->
        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-databind</artifactId>
            <version>${jackson.version}</version>
        </dependency>

        <!--  LOG4J2 -->
        <dependency>
            <groupId>org.apache.logging.log4j</groupId>
            <artifactId>log4j-api</artifactId>
            <version>${log4j.version}</version>
        </dependency>
        <dependency>
            <groupId>org.apache.logging.log4j</groupId>
            <artifactId>log4j-core</artifactId>
            <version>${log4j.version}</version>
        </dependency>

        <!--  JWT TOKEN -->
        <dependency>
            <groupId>com.nimbusds</groupId>
            <artifactId>nimbus-jose-jwt</artifactId>
            <version>${jose.jwt.version}</version>
        </dependency>


    </dependencies>


    <properties>
        <jose.jwt.version>4.39.2</jose.jwt.version>
        <spring-security.version>4.2.3.RELEASE</spring-security.version>
        <spring.version>4.3.9.RELEASE</spring.version>
        <log4j.version>2.8.2</log4j.version>
        <jersey.version>2.9.1</jersey.version>
        <jackson.version>2.8.9</jackson.version>
        <servlet-api.version>3.1.0</servlet-api.version>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    </properties>
</project>

Answer 1

您缺少 web.xml 中的一些重要点

 // For java config, you don't want to use .xml 
  // you have to include AnnotationConfigWebApplicationContext
    <context-param>
        <param-name>contextClass</param-name>
        <param-value>
org.springframework.web.context.support.AnnotationConfigWebApplicationContext
      </param-value>
    </context-param>

    // Location of your Configuration class
    <context-param>
        <param-name>contextConfigLocation</param-name>
        <param-value>my.package.AppConfig</param-value>
    </context-param>

    // To load context
    <listener>
        <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
    </listener>

    // Spring Servlet
    <servlet>
        <servlet-name>SpringApplication</servlet-name>
        <servlet-class>org.glassfish.jersey.servlet.ServletContainer</servlet-class>
   // Your controllers
        <init-param>
            <param-name>jersey.config.server.provider.classnames</param-name>
            <param-value>my.package.controllers.HomeController</param-value>
        </init-param>
        <load-on-startup>1</load-on-startup>
    </servlet>

    // Servlet url mapping
    <servlet-mapping>
        <servlet-name>SpringApplication</servlet-name>
        <url-pattern>/*</url-pattern>
    </servlet-mapping>

添加 Controller 类

@Component
@Path("/home")
public class HomeController {

更新: 据了解，问题的作者只对 Spring DI 感兴趣，不涉及 Spring MVC，下面是简单的配置引导 WebApplicationInitializer 以编程方式配置 ServletContext，无需 web.xml。请注意，这需要 Servlet 3.0+ 容器。

public class ApplicationInitializer implements WebApplicationInitializer {

    @Override
    public void onStartup(ServletContext servletContext)  throws ServletException {

        AnnotationConfigWebApplicationContext context 
          = new AnnotationConfigWebApplicationContext();

        servletContext.addListener(new ContextLoaderListener(context));
        servletContext.setInitParameter(
          "contextConfigLocation", "com.package.my");
    }
}