java.lang.NoClassDefFoundError: com.arangodb.ArangoDB$Builder Tomcat 9.0.4，Maven

Question

我有java.lang.ClassNotFoundException: com.arangodb.ArangoDB$Builder错误，但不是在编译期间，而是在运行时。

完全堆栈跟踪：

java.lang.NoClassDefFoundError: com/arangodb/ArangoDB$Builder
    at dbmanager.ArangoDBManager.<init>(ArangoDBManager.java:12)
    at dbmanager.DbManager.createExercise(DbManager.java:296)
    at main.CreateProjectServlet.processRequest(CreateProjectServlet.java:34)
    at main.CreateProjectServlet.doPost(CreateProjectServlet.java:21)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:660)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:741)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
    at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53)
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:199)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96)
    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:502)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:140)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:81)
    at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:651)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:87)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:342)
    at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:417)
    at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66)
    at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:754)
    at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1376)
    at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
    at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
    at java.lang.Thread.run(Thread.java:748)
Caused by: java.lang.ClassNotFoundException: com.arangodb.ArangoDB$Builder
    at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1275)
    at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1104)
    ... 28 more

我所读到的(而且我读了很多)可能是由于编译过程中出现的运行时女巫缺少类造成的。这有点道理，但我没有找到解决问题的办法。

当我从那个类中的main调用类(ArangoDBManager)时，它正常工作，所以必须在服务器上出现问题。

我使用Tomcat 9.0.4、Maven和Java 8。

我的pom.xml：

<groupId>groupId</groupId>
<artifactId>JavaEETomcat</artifactId>
<version>1.0-SNAPSHOT</version>

<build>
    <plugins>
        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-compiler-plugin</artifactId>
            <version>3.7.0</version>
            <configuration>
                <source>1.8</source>
                <target>1.8</target>
            </configuration>
        </plugin>
    </plugins>
</build>


<dependencies>
    <dependency>
        <groupId>mysql</groupId>
        <artifactId>mysql-connector-java</artifactId>
        <version>5.1.45</version>
    </dependency>

    <dependency>
        <groupId>com.google.code.gson</groupId>
        <artifactId>gson</artifactId>
        <version>2.8.4</version>
        <scope>provided</scope>
    </dependency>

    <dependency>
        <groupId>com.arangodb</groupId>
        <artifactId>arangodb-java-driver</artifactId>
        <version>4.3.0</version>
    </dependency>

    <dependency>
        <groupId>javax</groupId>
        <artifactId>javaee-api</artifactId>
        <version>7.0</version>
        <scope>provided</scope>
    </dependency>

    <dependency>
    <groupId>javax.servlet</groupId>
    <artifactId>javax.servlet-api</artifactId>
    <version>3.0.1</version>
    <scope>provided</scope>
</dependency>
</dependencies>

​

我试过几个版本的arangodb-java-驱动程序，但是没有用。

类来处理ArangoDB：

import com.arangodb.ArangoDB;
import com.arangodb.entity.BaseDocument;

public class ArangoDBManager {
    private final ArangoDB arangoDB;
    static final String DB = "DP";
    static final String COLLECTION = "user_exercise_files";

public ArangoDBManager() {
    arangoDB = new ArangoDB.Builder().password("********").build();
}

public void insertDocument(BaseDocument document) {
    arangoDB.db(DB).collection(COLLECTION).insertDocument(document);
}

public void deleteDocument(String key) {
    arangoDB.db(DB).collection(COLLECTION).deleteDocument(key);
}

public BaseDocument getDocument(String key) {
    return arangoDB.db(DB).collection(COLLECTION).getDocument(key,
            BaseDocument.class);
}

错误正在构造函数中生成。

我有一个类路径类：模块依赖

如果我忘了一些信息让我知道。我希望有人有什么想法，我觉得我已经什么都试过了。

Answer 1

我通过将.jar文件添加到Tomcat上的lib文件夹来解决这个问题。看起来它是由损坏的maven引起的，所以干净地安装maven也会有帮助。

Answer 2

我认为您需要将arangodb-java-驱动程序的类路径范围更改为提供。