如何修复 HTTP 状态 500 - Servlet.init() for servlet jersey 抛出异常？

Question

I am trying to create a web service with Restful API using Tomcat and Maven. After pulling some unversioned files, I started constantly getting a 500 error whenever I attempted to do an XMLHTTPrequest. I tried recreating the artifacts and the target files however the response did not change. I tried adding a breakpoint to the code supposed to be reached by the GET request however the debugger did not start so I assumed it was a path issue but the path appears to be working clearly.

error in java

    @Path("{version}")
public class VersionResource {

    @Secured
    @Path("/get")
    @GET
    @Produces("application/json")   //returns all the questions in the CRFversion that corresponds to the given string version
    public List<Question> getCRFVersion(@PathParam("version") String version) throws SQLException, ClassNotFoundException {
            return Arrays.asList(Optional.of(CRFversionDAO.instance.getVersion(version)).orElse(new Question[0]));
    }

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>nl.utwente.di</groupId>
<artifactId>CRFdatabase</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>war</packaging>
<properties>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
</properties>

<name>JDBC Adapter for JCasbin</name>
<description>Load policy from JDBC supported database or save policy to it</description>
<url>https://github.com/jcasbin/jdbc-adapter</url>
<inceptionYear>2018</inceptionYear>

<build>
    <finalName>${project.artifactId}</finalName>
    <plugins>
        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-compiler-plugin</artifactId>
            <version>3.8.0</version>
            <configuration>
                <release>11</release>
            </configuration>
        </plugin>
        <plugin>
            <groupId>org.eluder.coveralls</groupId>
            <artifactId>coveralls-maven-plugin</artifactId>
            <version>4.3.0</version>
        </plugin>

        <plugin>
            <groupId>org.jacoco</groupId>
            <artifactId>jacoco-maven-plugin</artifactId>
            <version>0.7.6.201602180812</version>
            <executions>
                <execution>
                    <id>prepare-agent</id>
                    <goals>
                        <goal>prepare-agent</goal>
                    </goals>
                </execution>
            </executions>
        </plugin>
        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-compiler-plugin</artifactId>
            <configuration>
                <source>8</source>
                <target>8</target>
            </configuration>
        </plugin>

    </plugins>
</build>
<dependencies>
    <dependency>
        <groupId>org.junit.jupiter</groupId>
        <artifactId>junit-jupiter-api</artifactId>
        <version>5.6.1</version>
    </dependency>

    <dependency>
        <groupId>org.junit.jupiter</groupId>
        <artifactId>junit-jupiter-engine</artifactId>
        <version>5.6.1</version>
    </dependency>

    <dependency>
        <groupId>com.fasterxml.jackson.core</groupId>
        <artifactId>jackson-core</artifactId>
        <version>2.5.3</version>
    </dependency>

    <dependency>
        <groupId>javax.servlet</groupId>
        <artifactId>javax.servlet-api</artifactId>
        <version>3.1.0</version>
        <scope>provided</scope>
    </dependency>

    <!-- https://mvnrepository.com/artifact/org.glassfish.jersey.containers/jersey-container-servlet -->
    <dependency>
        <groupId>org.glassfish.jersey.containers</groupId>
        <artifactId>jersey-container-servlet</artifactId>
        <version>2.30.1</version>
    </dependency>

    <dependency>
        <groupId>org.glassfish.jersey.inject</groupId>
        <artifactId>jersey-hk2</artifactId>
        <version>2.30.1</version>
    </dependency>

    <!-- Required only when you are using JAX-RS Client -->
    <dependency>
        <groupId>org.glassfish.jersey.core</groupId>
        <artifactId>jersey-client</artifactId>
        <version>2.30.1</version>
    </dependency>

    <!-- https://mvnrepository.com/artifact/org.glassfish.jersey.media/jersey-media-json-jackson -->
    <dependency>
        <groupId>org.glassfish.jersey.media</groupId>
        <artifactId>jersey-media-json-jackson</artifactId>
        <version>2.30.1</version>
    </dependency>

    <!-- https://mvnrepository.com/artifact/jakarta.xml.bind/jakarta.xml.bind-api -->
    <dependency>
        <groupId>jakarta.xml.bind</groupId>
        <artifactId>jakarta.xml.bind-api</artifactId>
        <version>2.3.3</version>
    </dependency>

    <!-- https://mvnrepository.com/artifact/org.glassfish.jaxb/jaxb-runtime -->
    <dependency>
        <groupId>org.glassfish.jaxb</groupId>
        <artifactId>jaxb-runtime</artifactId>
        <version>2.3.3</version>
    </dependency>
    <dependency>
        <groupId>junit</groupId>
        <artifactId>junit</artifactId>
        <version>4.11</version>
        <scope>test</scope>
    </dependency>
    <dependency>
        <groupId>org.casbin</groupId>
        <artifactId>jcasbin</artifactId>
        <version>1.1.0</version>
    </dependency>
    <dependency>
        <groupId>mysql</groupId>
        <artifactId>mysql-connector-java</artifactId>
        <version>8.0.12</version>
        <scope>test</scope>
    </dependency>
    <!-- https://mvnrepository.com/artifact/com.oracle/ojdbc -->
    <dependency>
        <groupId>com.oracle.database.jdbc</groupId>
        <artifactId>ojdbc6</artifactId>
        <version>11.2.0.4</version>
    </dependency>
    <!-- https://mvnrepository.com/artifact/org.postgresql/postgresql -->
    <dependency>
        <groupId>org.postgresql</groupId>
        <artifactId>postgresql</artifactId>
        <version>42.2.12</version>
    </dependency>
    <!-- https://mvnrepository.com/artifact/com.microsoft.sqlserver/mssql-jdbc -->
    <dependency>
        <groupId>com.microsoft.sqlserver</groupId>
        <artifactId>mssql-jdbc</artifactId>
        <version>8.2.2.jre8</version>
    </dependency>
    <dependency>
        <groupId>mysql</groupId>
        <artifactId>mysql-connector-java</artifactId>
        <version>8.0.12</version>
        <scope>compile</scope>
    </dependency>
    <dependency>
        <groupId>junit</groupId>
        <artifactId>junit</artifactId>
        <version>4.13</version>
        <scope>compile</scope>
    </dependency>



</dependencies>

error code

Type Exception Report

Message Servlet.init() for servlet [javax.ws.rs.core.Application] threw exception

Description The server encountered an unexpected condition that prevented it from fulfilling the request.

Exception

javax.servlet.ServletException: Servlet.init() for servlet [javax.ws.rs.core.Application] threw exception
    org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:543)
    org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:81)
    org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:690)
    org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:343)
    org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:615)
    org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:65)
    org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:818)
    org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1627)
    org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)
    java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128)
    java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628)
    org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
    java.base/java.lang.Thread.run(Thread.java:830)
Root Cause

java.lang.IllegalStateException: The resource configuration is not modifiable in this context.
    org.glassfish.jersey.server.ResourceConfig$ImmutableState.register(ResourceConfig.java:248)
    org.glassfish.jersey.server.ResourceConfig$ImmutableState.register(ResourceConfig.java:195)
    org.glassfish.jersey.server.ResourceConfig.register(ResourceConfig.java:428)
    org.glassfish.jersey.servlet.WebComponent.<init>(WebComponent.java:306)
    org.glassfish.jersey.servlet.ServletContainer.init(ServletContainer.java:154)
    org.glassfish.jersey.servlet.ServletContainer.init(ServletContainer.java:347)
    javax.servlet.GenericServlet.init(GenericServlet.java:158)
    org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:543)
    org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:81)
    org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:690)
    org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:343)
    org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:615)
    org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:65)
    org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:818)
    org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1627)
    org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)
    java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128)
    java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628)
    org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
    java.base/java.lang.Thread.run(Thread.java:830)

web.xml

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee 
         http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd"
         version="3.1">

    <servlet>
        <servlet-name>javax.ws.rs.core.Application</servlet-name>
    </servlet>
    <servlet-mapping>
        <servlet-name>javax.ws.rs.core.Application</servlet-name>
        <url-pattern>/rest/*</url-pattern>
    </servlet-mapping>
</web-app>

Answer 1

I think when I was reading through the documentation on Applications, you need to use javax.ws.rs.Application, no "core" in it. I may be mistaken though, or the version may be different and call for different verbage.

Take a look here at 4.7.1.1: https://eclipse-ee4j.github.io/jersey.github.io/documentation/latest/deployment.html#deployment.servlet.2