java - 无法使用 Jetty、RestEasy 和 Guice 从导出的 JAR 中找到消息正文阅读器

Question

我有一个非常具体的问题。从 Eclipse 运行时该应用程序工作正常(没有任何参数)。但给出

ERROR: RESTEASY002010: Failed to execute javax.ws.rs.NotSupportedException: RESTEASY003200: Could not find message body reader for type: class hu.edudroid.matek.web.endpoints.RequestData of content type: application/json

运行导出的 JAR 时出现异常(mvn cleancompile assembly:single)。否则注入(inject)工作正常，不依赖 JSON 解析的端点工作正常。 get方法工作正常，post方法抛出错误。我不知道该怎么办。

我的服务器:

public static void main(String[] args) throws Exception {
    Injector injector = Guice.createInjector(new MathModule(args));
    int port = args.length > 0 ? Integer.parseInt(args[1]):8081; 
    Server server = new Server(port);
    ServletContextHandler servletHandler = new ServletContextHandler();
    servletHandler.addEventListener(injector.getInstance(GuiceResteasyBootstrapServletContextListener.class));

    ServletHolder sh = new ServletHolder(HttpServletDispatcher.class);
    servletHandler.addServlet(sh, "/*");

    server.setHandler(servletHandler);
    server.start();
    server.join();
}

我的依赖项:

public class MathModule extends RequestScopeModule {

    @Override
    public void configure() {
        super.configure();
        bind(TestEndpoint.class).in(Singleton.class);
    }
}

我的端点:

@Path("/test")
public class TestEndpoint {

    @GET
    @Path("/")
    @Produces(MediaType.APPLICATION_JSON)
    @Consumes(MediaType.APPLICATION_JSON)   
    public String get() {
        return "Hello World";
    }

    @POST
    @Path("/")
    @Produces(MediaType.APPLICATION_JSON)
    @Consumes(MediaType.APPLICATION_JSON)   
    public String post(RequestData value) {
        return "Hello " + value.getName();
    }
}

POJO:

@Data
@NoArgsConstructor
public class RequestData {
    private String name;
}

最后是 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>hu.edudroid.matek</groupId>
    <artifactId>core</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>jar</packaging>

    <name>core</name>
    <url>http://maven.apache.org</url>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    </properties>

    <dependencies>

        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <version>1.16.18</version>
            <scope>compile</scope>
        </dependency>

        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.12</version>
        </dependency>

        <dependency>
            <groupId>org.mockito</groupId>
            <artifactId>mockito-core</artifactId>
            <version>2.8.47</version>
            <scope>compile</scope>
        </dependency>

        <dependency>
            <groupId>com.google.guava</groupId>
            <artifactId>guava</artifactId>
            <version>21.0</version>
        </dependency>

        <dependency>
            <groupId>com.google.inject</groupId>
            <artifactId>guice</artifactId>
            <version>4.1.0</version>
        </dependency>

        <dependency>
            <groupId>org.eclipse.jetty</groupId>
            <artifactId>jetty-server</artifactId>
            <version>9.4.5.v20170502</version>
        </dependency>

        <dependency>
            <groupId>org.eclipse.jetty</groupId>
            <artifactId>jetty-servlet</artifactId>
            <version>9.4.5.v20170502</version>
        </dependency>

        <dependency>
            <groupId>org.jboss.resteasy</groupId>
            <artifactId>resteasy-jaxrs</artifactId>
            <version>3.1.3.Final</version>
        </dependency>

        <dependency>
            <groupId>org.jboss.resteasy</groupId>
            <artifactId>resteasy-servlet-initializer</artifactId>
            <version>3.1.3.Final</version>
        </dependency>

        <dependency>
            <groupId>org.jboss.resteasy</groupId>
            <artifactId>resteasy-jackson2-provider</artifactId>
            <version>3.1.3.Final</version>
        </dependency>

        <dependency>
            <groupId>org.jboss.resteasy</groupId>
            <artifactId>resteasy-guice</artifactId>
            <version>3.1.3.Final</version>
        </dependency>

        <dependency>
            <groupId>com.fasterxml.jackson.core</groupId>
            <artifactId>jackson-core</artifactId>
            <version>2.8.9</version>
        </dependency>

    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>3.6.1</version>
                <configuration>
                    <source>1.8</source>
                    <target>1.8</target>
                </configuration>
            </plugin>
            <plugin>
                <artifactId>maven-assembly-plugin</artifactId>
                <configuration>
                    <archive>
                        <manifest>
                            <mainClass>hu.edudroid.matek.web.main.MatekServer</mainClass>
                        </manifest>
                    </archive>
                    <descriptorRefs>
                        <descriptorRef>jar-with-dependencies</descriptorRef>
                    </descriptorRefs>
                </configuration>
            </plugin>
        </plugins>
    </build>
</project>

Answer 1

当您使用 jar-with-dependencies 程序集描述符时，所有依赖项 jar 都会提取到一处。有时这个 jar 可以包含同名的文件。在这种情况下，只有第一个 jar 中的文件才会包含在结果 jar 中。 在程序集文件 META-INF\services\javax.ws.rs.ext.Providers 中存在两个依赖项 jar(resteasy-jaxrs 和resteasy-jettison-provider)。最后一个 jar 包含 application/json 内容类型的提供程序，但没有服务描述 Resteasy 找不到它。您可以尝试shade plugin带变压器concatenate service description files

<plugin>
    <groupId>org.apache.maven.plugins</groupId>
    <artifactId>maven-shade-plugin</artifactId>
    <version>3.0.0</version>
    <executions>
        <execution>
            <goals>
                <goal>shade</goal>
            </goals>
            <configuration>
                <transformers>
                    <transformer implementation="org.apache.maven.plugins.shade.resource.ServicesResourceTransformer"/>
                </transformers>
            </configuration>
        </execution>
    </executions>
</plugin>