Dropwizard 客户端类型不匹配答案

【问题标题】：Dropwizard client type mismatchDropwizard 客户端类型不匹配
【发布时间】：2017-01-09 07:08:49
【问题描述】：

首先介绍一下背景知识，我正在尝试在 Eclipse 中设计一个 RESTfull 应用程序，并且我一直在使用此处提供的 pdf 书籍自学 DropWizard：https://github.com/adhulappanavar/Dropwizard/blob/master/RESTful%20Web%20Services%20with%20Dropwizard%20%5BeBook%5D.pdf

这本书大约有两年的历史了，因此我遇到了一些错误，但是我的应用程序入口类 (rappApplication) 中的以下错误确实让我感到难过。

     Exception in thread "main" java.lang.ClassCastException: org.glassfish.jersey.client.JerseyClient cannot be cast to com.sun.jersey.api.client.Client
at edu.udel.rapp.rapp.rappApplication.run(rappApplication.java:50)
at edu.udel.rapp.rapp.rappApplication.run(rappApplication.java:1)
at io.dropwizard.cli.EnvironmentCommand.run(EnvironmentCommand.java:43)
at io.dropwizard.cli.ConfiguredCommand.run(ConfiguredCommand.java:85)
at io.dropwizard.cli.Cli.run(Cli.java:75)
at io.dropwizard.Application.run(Application.java:79)
at edu.udel.rapp.rapp.rappApplication.main(rappApplication.java:31)

在本课中：

import io.dropwizard.Application;
import io.dropwizard.setup.Bootstrap;
import io.dropwizard.setup.Environment;

import org.skife.jdbi.v2.DBI;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import io.dropwizard.Application;
import io.dropwizard.Configuration;
import io.dropwizard.client.JerseyClientBuilder;

import io.dropwizard.jdbi.DBIFactory;
import edu.udel.rapp.resources.ClientResource;
import edu.udel.rapp.resources.StudentResource;

import com.sun.jersey.api.client.Client;



public class rappApplication extends Application<rappConfiguration> {
private static final Logger LOGGER =
        LoggerFactory.getLogger(rappApplication.class);

public static void main(final String[] args) throws Exception {
    new rappApplication().run(args);
}

@Override
public String getName() {
    return "rapp";
}

@Override
public void initialize(final Bootstrap<rappConfiguration> bootstrap) {
    // TODO: application initialization
}




@Override
public void run(rappConfiguration c, Environment e) throws Exception {

    final Client client = new JerseyClientBuilder(e).build("REST Client");
    e.jersey().register(new ClientResource(client));


    LOGGER.info("Method App#run() called");
    for (int i=0; i < c.getMessageRepetitions(); i++) {
    System.out.println(c.getMessage());
}
System.out.println(c.getAdditionalMessage());
// Create a DBI factory and build a JDBI instance
final DBIFactory factory = new DBIFactory();
final DBI jdbi = factory.build(e, c.getDataSourceFactory(), "mysql");
// Add the resource to the environment
e.jersey().register(new StudentResource(jdbi, e.getValidator()));
}






 }

现在在书中，我的运行方法中客户端的初始化没有需要强制转换为客户端，但是 Eclipse 给了我一个编译错误（“类型不匹配：无法从 javax.ws 转换。 rs.client.Client 到 com.sun.jersey.api.client.Client") 如果我不在那里投射到客户端...然后在运行时导致错误。

此外，当我为我的班级导入的内容是 io.dropwizard.client.JerseyClientBuilder 时，为什么 Eclipse 会出现“org.glassfish.jersey.client.JerseyClient”问题，我对此感到困惑；

这几乎就像 Eclipse 对 Client 到底是什么感到困惑。

编辑：我在 pom.xml 中使用具有以下依赖项的 Maven，

<dependencies>
<dependency>
  <groupId>junit</groupId>
  <artifactId>junit</artifactId>
  <version>3.8.1</version>
  <scope>test</scope>
</dependency>

<dependency>
    <groupId>com.fasterxml.jackson.core</groupId>
    <artifactId>jackson-core</artifactId>
    <version>2.6.7</version>
</dependency>

<dependency>
    <groupId>io.dropwizard</groupId>
    <artifactId>dropwizard-testing</artifactId>
    <version>${dropwizard.version}</version>
    <scope>test</scope>
</dependency>

<dependency>
    <groupId>io.dropwizard</groupId>
    <artifactId>dropwizard-client</artifactId>
    <version>${dropwizard.version}</version>
</dependency>

<dependency>
    <groupId>io.dropwizard</groupId>
    <artifactId>dropwizard-assets</artifactId>
    <version>${dropwizard.version}</version>
</dependency>


<dependency>
    <groupId>io.dropwizard</groupId>
    <artifactId>dropwizard-forms</artifactId>
    <version>${dropwizard.version}</version>
</dependency>

<dependency>
    <groupId>com.h2database</groupId>
    <artifactId>h2</artifactId>
    <version>1.4.190</version>
</dependency>

<dependency>
    <groupId>com.google.api-client</groupId>
    <artifactId>google-api-client</artifactId>
    <version>1.22.0</version>
</dependency>

<dependency>
    <groupId>com.google.oauth-client</groupId>
    <artifactId>google-oauth-client-jetty</artifactId>
    <version>1.22.0</version>
</dependency>

<dependency>
    <groupId>com.google.apis</groupId>
    <artifactId>google-api-services-drive</artifactId>
    <version>v3-rev32-1.22.0</version>
</dependency>

<dependency>
    <groupId>mysql</groupId>
    <artifactId>mysql-connector-java</artifactId>
    <version>5.1.6</version>
</dependency>

 <dependency>
    <groupId>io.dropwizard</groupId>
    <artifactId>dropwizard-jdbi</artifactId>
    <version>${dropwizard.version}</version>
</dependency>

<!-- https://mvnrepository.com/artifact/com.sun.jersey/jersey-core -->
<dependency>
    <groupId>com.sun.jersey</groupId>
    <artifactId>jersey-core</artifactId>
    <version>1.8</version>
</dependency>




</dependencies>

执行 mvn clean dependency:tree 给出以下输出

[INFO] Scanning for projects...
[INFO]                                                                         
[INFO] ------------------------------------------------------------------------
[INFO] Building rapp 0.0.1-SNAPSHOT
[INFO] ------------------------------------------------------------------------
[INFO] 
[INFO] --- maven-clean-plugin:2.5:clean (default-clean) @ rapp ---
[INFO] 
[INFO] --- maven-dependency-plugin:2.8:tree (default-cli) @ rapp ---
[INFO] edu.udel.rapp:rapp:jar:0.0.1-SNAPSHOT
[INFO] +- junit:junit:jar:3.8.1:test
[INFO] +- com.fasterxml.jackson.core:jackson-core:jar:2.6.7:compile
[INFO] +- io.dropwizard:dropwizard-testing:jar:1.0.4:test
[INFO] |  +- io.dropwizard:dropwizard-core:jar:1.0.4:compile
[INFO] |  |  +- io.dropwizard:dropwizard-util:jar:1.0.4:compile
[INFO] |  |  |  +- com.fasterxml.jackson.core:jackson-annotations:jar:2.7.8:compile
[INFO] |  |  |  +- com.google.guava:guava:jar:19.0:compile
[INFO] |  |  |  \- joda-time:joda-time:jar:2.9.4:compile
[INFO] |  |  +- io.dropwizard:dropwizard-jackson:jar:1.0.4:compile
[INFO] |  |  |  +- com.fasterxml.jackson.core:jackson-databind:jar:2.7.8:compile
[INFO] |  |  |  +- com.fasterxml.jackson.datatype:jackson-datatype-guava:jar:2.7.8:compile
[INFO] |  |  |  +- com.fasterxml.jackson.datatype:jackson-datatype-jsr310:jar:2.7.8:compile
[INFO] |  |  |  +- com.fasterxml.jackson.datatype:jackson-datatype-jdk8:jar:2.7.8:compile
[INFO] |  |  |  +- com.fasterxml.jackson.module:jackson-module-afterburner:jar:2.7.8:compile
[INFO] |  |  |  \- com.fasterxml.jackson.datatype:jackson-datatype-joda:jar:2.7.8:compile
[INFO] |  |  +- io.dropwizard:dropwizard-validation:jar:1.0.4:compile
[INFO] |  |  |  +- org.hibernate:hibernate-validator:jar:5.2.4.Final:compile
[INFO] |  |  |  |  +- org.jboss.logging:jboss-logging:jar:3.2.1.Final:compile
[INFO] |  |  |  |  \- com.fasterxml:classmate:jar:1.1.0:compile
[INFO] |  |  |  \- org.glassfish:javax.el:jar:3.0.0:compile
[INFO] |  |  +- io.dropwizard:dropwizard-configuration:jar:1.0.4:compile
[INFO] |  |  |  +- com.fasterxml.jackson.dataformat:jackson-dataformat-yaml:jar:2.7.8:compile
[INFO] |  |  |  |  \- org.yaml:snakeyaml:jar:1.15:compile
[INFO] |  |  |  \- org.apache.commons:commons-lang3:jar:3.4:compile
[INFO] |  |  +- io.dropwizard:dropwizard-logging:jar:1.0.4:compile
[INFO] |  |  |  +- io.dropwizard.metrics:metrics-logback:jar:3.1.2:compile
[INFO] |  |  |  +- org.slf4j:jul-to-slf4j:jar:1.7.21:compile
[INFO] |  |  |  +- ch.qos.logback:logback-core:jar:1.1.7:compile
[INFO] |  |  |  +- org.slf4j:log4j-over-slf4j:jar:1.7.21:compile
[INFO] |  |  |  +- org.slf4j:jcl-over-slf4j:jar:1.7.21:compile
[INFO] |  |  |  \- org.eclipse.jetty:jetty-util:jar:9.3.9.v20160517:compile
[INFO] |  |  +- io.dropwizard:dropwizard-metrics:jar:1.0.4:compile
[INFO] |  |  +- io.dropwizard:dropwizard-jersey:jar:1.0.4:compile
[INFO] |  |  |  +- org.glassfish.jersey.ext:jersey-metainf-services:jar:2.23.2:compile
[INFO] |  |  |  +- org.glassfish.jersey.ext:jersey-bean-validation:jar:2.23.2:compile
[INFO] |  |  |  +- io.dropwizard.metrics:metrics-jersey2:jar:3.1.2:compile
[INFO] |  |  |  +- com.fasterxml.jackson.jaxrs:jackson-jaxrs-json-provider:jar:2.7.8:compile
[INFO] |  |  |  |  +- com.fasterxml.jackson.jaxrs:jackson-jaxrs-base:jar:2.7.8:compile
[INFO] |  |  |  |  \- com.fasterxml.jackson.module:jackson-module-jaxb-annotations:jar:2.7.8:compile
[INFO] |  |  |  +- org.glassfish.jersey.containers:jersey-container-servlet:jar:2.23.2:compile
[INFO] |  |  |  +- org.eclipse.jetty:jetty-server:jar:9.3.9.v20160517:compile
[INFO] |  |  |  |  +- javax.servlet:javax.servlet-api:jar:3.1.0:compile
[INFO] |  |  |  |  \- org.eclipse.jetty:jetty-io:jar:9.3.9.v20160517:compile
[INFO] |  |  |  +- org.eclipse.jetty:jetty-webapp:jar:9.3.9.v20160517:compile
[INFO] |  |  |  |  \- org.eclipse.jetty:jetty-xml:jar:9.3.9.v20160517:compile
[INFO] |  |  |  \- org.eclipse.jetty:jetty-continuation:jar:9.3.9.v20160517:compile
[INFO] |  |  +- io.dropwizard:dropwizard-jetty:jar:1.0.4:compile
[INFO] |  |  |  +- io.dropwizard.metrics:metrics-jetty9:jar:3.1.2:compile
[INFO] |  |  |  +- org.eclipse.jetty:jetty-servlet:jar:9.3.9.v20160517:compile
[INFO] |  |  |  |  \- org.eclipse.jetty:jetty-security:jar:9.3.9.v20160517:compile
[INFO] |  |  |  +- org.eclipse.jetty:jetty-servlets:jar:9.3.9.v20160517:compile
[INFO] |  |  |  \- org.eclipse.jetty:jetty-http:jar:9.3.9.v20160517:compile
[INFO] |  |  +- io.dropwizard:dropwizard-lifecycle:jar:1.0.4:compile
[INFO] |  |  +- io.dropwizard.metrics:metrics-core:jar:3.1.2:compile
[INFO] |  |  +- io.dropwizard.metrics:metrics-jvm:jar:3.1.2:compile
[INFO] |  |  +- io.dropwizard.metrics:metrics-servlets:jar:3.1.2:compile
[INFO] |  |  |  \- io.dropwizard.metrics:metrics-json:jar:3.1.2:compile
[INFO] |  |  +- io.dropwizard.metrics:metrics-healthchecks:jar:3.1.2:compile
[INFO] |  |  +- io.dropwizard:dropwizard-request-logging:jar:1.0.4:compile
[INFO] |  |  |  \- ch.qos.logback:logback-access:jar:1.1.7:compile
[INFO] |  |  +- net.sourceforge.argparse4j:argparse4j:jar:0.7.0:compile
[INFO] |  |  \- org.eclipse.jetty.toolchain.setuid:jetty-setuid-java:jar:1.0.3:compile
[INFO] |  +- org.mockito:mockito-core:jar:2.0.54-beta:test
[INFO] |  |  \- net.bytebuddy:byte-buddy:jar:1.3.16:test
[INFO] |  +- org.objenesis:objenesis:jar:2.3:test
[INFO] |  +- org.assertj:assertj-core:jar:3.4.1:test
[INFO] |  \- org.glassfish.jersey.test-framework.providers:jersey-test-framework-provider-inmemory:jar:2.23.2:test
[INFO] |     +- org.glassfish.jersey.test-framework:jersey-test-framework-core:jar:2.23.2:test
[INFO] |     |  \- org.glassfish.jersey.containers:jersey-container-servlet-core:jar:2.23.2:compile
[INFO] |     \- org.ow2.asm:asm-debug-all:jar:5.0.4:test
[INFO] +- io.dropwizard:dropwizard-client:jar:1.0.4:compile
[INFO] |  +- org.glassfish.jersey.core:jersey-client:jar:2.23.2:compile
[INFO] |  +- org.apache.httpcomponents:httpclient:jar:4.5.2:compile
[INFO] |  |  +- org.apache.httpcomponents:httpcore:jar:4.4.4:compile
[INFO] |  |  \- commons-codec:commons-codec:jar:1.9:compile
[INFO] |  +- io.dropwizard.metrics:metrics-httpclient:jar:3.1.2:compile
[INFO] |  \- org.glassfish.jersey.connectors:jersey-apache-connector:jar:2.23.2:compile
[INFO] +- io.dropwizard:dropwizard-assets:jar:1.0.4:compile
[INFO] |  \- io.dropwizard:dropwizard-servlets:jar:1.0.4:compile
[INFO] |     +- org.slf4j:slf4j-api:jar:1.7.21:compile
[INFO] |     +- io.dropwizard.metrics:metrics-annotation:jar:3.1.2:compile
[INFO] |     \- ch.qos.logback:logback-classic:jar:1.1.7:compile
[INFO] +- io.dropwizard:dropwizard-forms:jar:1.0.4:compile
[INFO] |  \- org.glassfish.jersey.media:jersey-media-multipart:jar:2.23.2:compile
[INFO] |     \- org.jvnet.mimepull:mimepull:jar:1.9.6:compile
[INFO] +- com.h2database:h2:jar:1.4.190:compile
[INFO] +- com.google.api-client:google-api-client:jar:1.22.0:compile
[INFO] |  +- com.google.oauth-client:google-oauth-client:jar:1.22.0:compile
[INFO] |  |  +- com.google.http-client:google-http-client:jar:1.22.0:compile
[INFO] |  |  \- com.google.code.findbugs:jsr305:jar:1.3.9:compile
[INFO] |  +- com.google.http-client:google-http-client-jackson2:jar:1.22.0:compile
[INFO] |  \- com.google.guava:guava-jdk5:jar:17.0:compile
[INFO] +- com.google.oauth-client:google-oauth-client-jetty:jar:1.22.0:compile
[INFO] |  +- com.google.oauth-client:google-oauth-client-java6:jar:1.22.0:compile
[INFO] |  \- org.mortbay.jetty:jetty:jar:6.1.26:compile
[INFO] |     +- org.mortbay.jetty:jetty-util:jar:6.1.26:compile
[INFO] |     \- org.mortbay.jetty:servlet-api:jar:2.5-20081211:compile
[INFO] +- com.google.apis:google-api-services-drive:jar:v3-rev32-1.22.0:compile
[INFO] +- mysql:mysql-connector-java:jar:5.1.6:compile
[INFO] +- io.dropwizard:dropwizard-jdbi:jar:1.0.4:compile
[INFO] |  +- io.dropwizard:dropwizard-db:jar:1.0.4:compile
[INFO] |  |  \- org.apache.tomcat:tomcat-jdbc:jar:8.5.3:compile
[INFO] |  |     \- org.apache.tomcat:tomcat-juli:jar:8.5.3:compile
[INFO] |  +- org.jdbi:jdbi:jar:2.73:compile
[INFO] |  \- io.dropwizard.metrics:metrics-jdbi:jar:3.1.2:compile
[INFO] +- org.glassfish.jersey.core:jersey-server:jar:2.11:compile
[INFO] |  +- org.glassfish.jersey.core:jersey-common:jar:2.11:compile
[INFO] |  |  +- org.glassfish.jersey.bundles.repackaged:jersey-guava:jar:2.11:compile
[INFO] |  |  \- org.glassfish.hk2:osgi-resource-locator:jar:1.0.1:compile
[INFO] |  +- javax.ws.rs:javax.ws.rs-api:jar:2.0:compile
[INFO] |  +- javax.annotation:javax.annotation-api:jar:1.2:compile
[INFO] |  +- org.glassfish.hk2:hk2-api:jar:2.3.0-b05:compile
[INFO] |  |  +- org.glassfish.hk2:hk2-utils:jar:2.3.0-b05:compile
[INFO] |  |  \- org.glassfish.hk2.external:aopalliance-repackaged:jar:2.3.0-b05:compile
[INFO] |  +- org.glassfish.hk2.external:javax.inject:jar:2.3.0-b05:compile
[INFO] |  +- org.glassfish.hk2:hk2-locator:jar:2.3.0-b05:compile
[INFO] |  |  \- org.javassist:javassist:jar:3.18.1-GA:compile
[INFO] |  \- javax.validation:validation-api:jar:1.1.0.Final:compile
[INFO] \- com.sun.jersey:jersey-core:jar:1.8:compile
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS

【问题讨论】：

这是一个明显的依赖不匹配问题。请说明您使用的是哪种构建工具，并提供使用的依赖项。
@code 刚刚更新了我的操作
看起来与 jersey-core 的依赖冲突。确保从所有其他依赖项中排除此依赖项，以确保在运行时不使用其他版本
@code 感谢所有帮助！我不熟悉依赖冲突或排除，所以请耐心等待；我根据我能够做的一点点研究对 pom.xml 进行了修补，但没有骰子，如果我没有在我的应用程序文件中包含（客户端）它返回编译，如果我这样做了它给了我上述运行时错误。也许我在排除方面做错了？另外，为了将来参考，有没有办法判断它是否存在依赖不匹配问题？
您的 edit 2 没有用，而且是错误的。阅读有关 Maven 依赖项的信息，了解它们是如何注入到您的项目中的。告诉 maven 不要在您的项目中包含该工件（这是您排除的依赖项的一部分）。其他版本的 Jersey-core 可能来自任何其他依赖项（作为传递依赖项）。另外，尝试添加 jersey-server，如下所述：stackoverflow.com/questions/26906534/…

标签： java eclipse jersey client dropwizard

【解决方案1】：

如代码所示here，

new JerseyClientBuilder(e).build("REST Client");

返回javax.ws.rs.client.Client 类型的实例。但是您在代码中导入了com.sun.jersey.api.client.Client。

替换

导入 com.sun.jersey.api.client.Client;

与

导入 javax.ws.rs.client.Client

【讨论】：

不幸的是，我已经尝试过这样做，但没有成功；这是因为弹出了许多不同的错误，所以我会看看是否有办法解决这些问题并使其工作。话虽如此，本书作者确实确认依赖项存在问题，我希望尽快收到他们的回复，提供具体细节。