500 internal error while creating restAPI in jersey

Question

I am getting 500 internal error while executing a basic program on the rest API in a jersey project

Student.java

package com.api.api;


import javax.xml.bind.annotation.XmlRootElement;

@XmlRootElement
public class Student {
    private String name;
    private String subject;
    private String marks;

    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    public String getSubject() {
        return subject;
    }
    public void setSubject(String subject) {
        this.subject = subject;
    }
    public String getMarks() {
        return marks;
    }
    public void setMarks(String marks) {
        this.marks = marks;
    }
}

StudentResource.java

package com.api.api;

import javax.ws.rs.GET;
import javax.ws.rs.Path;
import javax.ws.rs.Produces;
import javax.ws.rs.core.MediaType;

@Path("student")
public class StudentResource {
    
    @GET
    @Produces(MediaType.APPLICATION_XML)
    public Student getStudents()
    {
        System.out.println("called...");
        Student s1=new Student();
        s1.setMarks("19");
        s1.setName("kart");
        s1.setSubject("maths");
        
        System.out.println(s1.getMarks());
        
        return s1;
       // return "<?xml version=\"1.0\"?>" + "<hello> Hello Jersey" + "</hello>";  
    }

}

this is my pom.xml file

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

    <build>
        <finalName>api</finalName>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <version>3.8.1</version>
                <inherited>true</inherited>
                <configuration>
                    <source>1.8</source>
                    <target>1.8</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>
        <dependency>
            <groupId>org.glassfish.jersey.containers</groupId>
            <artifactId>jersey-container-servlet-core</artifactId>
            <!-- use the following artifactId if you don't need servlet 2.x compatibility -->
            <!-- artifactId>jersey-container-servlet</artifactId -->
        </dependency>
        <dependency>
            <groupId>org.glassfish.jersey.inject</groupId>
            <artifactId>jersey-hk2</artifactId>
        </dependency>
        <dependency>
        <groupId>javax.xml.bind</groupId>
        <artifactId>jaxb-api</artifactId>
        <version>2.3.1</version>
        </dependency>
        
        <!-- uncomment this to get JSON support
        <dependency>
            <groupId>org.glassfish.jersey.media</groupId>
            <artifactId>jersey-media-json-binding</artifactId>
        </dependency>
        -->
    </dependencies>
    <properties>
        <jersey.version>2.26-b06</jersey.version>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    </properties>
</project>

where I added this dependency additionally

<dependency>
    <groupId>javax.xml.bind</groupId>
    <artifactId>jaxb-api</artifactId>
    <version>2.3.1</version>
</dependency>

this is the output I got

I suspect there is some issue with the XML bind, because when I return the XML as a string it is working fine but when i convert the object to XML i am getting internal error so please help me solving this

this is my file structure in eclipse

and also I am not able to see any error logs

Answer 1

Root cause analysis

ClassNotFoundException

Probably, the ClassNotFoundException is thrown by the org.glassfish.hk2.osgiresourcelocator.ServiceLoader#lookupProviderClasses method.

The ClassNotFoundException exception message:

java.lang.ClassNotFoundException: com.sun.xml.internal.bind.v2.ContextFactory

The ClassNotFoundException exception stacktrace:

java.lang.ClassNotFoundException: com.sun.xml.internal.bind.v2.ContextFactory
    at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:636)
    at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:182)
    at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:519)
    at javax.xml.bind.ServiceLoaderUtil.nullSafeLoadClass(ServiceLoaderUtil.java:122)
    at javax.xml.bind.ServiceLoaderUtil.safeLoadClass(ServiceLoaderUtil.java:155)
    at javax.xml.bind.ContextFinder.newInstance(ContextFinder.java:276)
    at javax.xml.bind.ContextFinder.find(ContextFinder.java:421)
    at javax.xml.bind.JAXBContext.newInstance(JAXBContext.java:721)
    at javax.xml.bind.JAXBContext.newInstance(JAXBContext.java:662)
    at org.glassfish.jersey.jaxb.internal.AbstractJaxbProvider.getStoredJaxbContext(AbstractJaxbProvider.java:311)
<…>

JAXBException

The mentioned above ClassNotFoundException exception is caught and rethrown as JAXBException by the javax.xml.bind.ContextFinder#newInstance(java.lang.Class[], java.util.Map, java.lang.String) method.

The JAXBException exception message:

javax.xml.bind.JAXBException: Implementation of JAXB-API has not been found on module path or classpath.

• with linked exception: [java.lang.ClassNotFoundException: com.sun.xml.internal.bind.v2.ContextFactory]

The JAXBException exception stacktrace:

javax.xml.bind.JAXBException: Implementation of JAXB-API has not been found on module path or classpath.
 - with linked exception:
[java.lang.ClassNotFoundException: com.sun.xml.internal.bind.v2.ContextFactory]
    at javax.xml.bind.ContextFinder.newInstance(ContextFinder.java:278)
    at javax.xml.bind.ContextFinder.find(ContextFinder.java:421)
    at javax.xml.bind.JAXBContext.newInstance(JAXBContext.java:721)
    at javax.xml.bind.JAXBContext.newInstance(JAXBContext.java:662)
    at org.glassfish.jersey.jaxb.internal.AbstractJaxbProvider.getStoredJaxbContext(AbstractJaxbProvider.java:311)
    at org.glassfish.jersey.jaxb.internal.AbstractJaxbProvider.getJAXBContext(AbstractJaxbProvider.java:296)
    at org.glassfish.jersey.jaxb.internal.AbstractJaxbProvider.getMarshaller(AbstractJaxbProvider.java:263)
    at org.glassfish.jersey.jaxb.internal.AbstractJaxbProvider.getMarshaller(AbstractJaxbProvider.java:230)
    at org.glassfish.jersey.jaxb.internal.AbstractRootElementJaxbProvider.writeTo(AbstractRootElementJaxbProvider.java:174)
    at org.glassfish.jersey.message.internal.WriterInterceptorExecutor$TerminalWriterInterceptor.invokeWriteTo(WriterInterceptorExecutor.java:266)
<…>
Caused by: java.lang.ClassNotFoundException: com.sun.xml.internal.bind.v2.ContextFactory
    at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:636)
    at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:182)
    at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:519)
<…>

Root cause

The root cause is described by the JAXBException exception message:

javax.xml.bind.JAXBException: Implementation of JAXB-API has not been found on module path or classpath.

Solution

Add the JAXB implementation Maven dependency.

For example, this one seems to work fine for the mentioned version of JAXB API:

<dependency>
    <groupId>com.sun.xml.bind</groupId>
    <artifactId>jaxb-impl</artifactId>
    <version>2.3.6</version>
    <scope>runtime</scope>
</dependency>