创建 JAXBContext 实例时出现 IndexOutOfBoundsException

Question

So this program is supposed to marshall the object I've created. I create an object and give value to every property it has, with the intention of generating a.xml with its data. To do so i have to make an instance of JAXBContext in which I specify the class of the object. And this is where i get the IndexOutOfBoundsException:

"JAXBContext jc = JAXBContext.newInstance(HealthTopic.class);"

Right as i get to the above mentioned line, i get

Output from ActividadXML3

```Exception in thread "main" java.lang.IndexOutOfBoundsException: Index: 1, Size: 1
    at java.util.ArrayList.rangeCheck(ArrayList.java:653)
    at java.util.ArrayList.get(ArrayList.java:429)
    at com.sun.xml.internal.bind.v2.model.impl.ClassInfoImpl.addProperty(ClassInfoImpl.java:885)
    at com.sun.xml.internal.bind.v2.model.impl.ClassInfoImpl.findFieldProperties(ClassInfoImpl.java:393)
    at com.sun.xml.internal.bind.v2.model.impl.ClassInfoImpl.getProperties(ClassInfoImpl.java:296)
    at com.sun.xml.internal.bind.v2.model.impl.RuntimeClassInfoImpl.getProperties(RuntimeClassInfoImpl.java:171)
    at com.sun.xml.internal.bind.v2.model.impl.ModelBuilder.getClassInfo(ModelBuilder.java:246)
    at com.sun.xml.internal.bind.v2.model.impl.RuntimeModelBuilder.getClassInfo(RuntimeModelBuilder.java:88)
    at com.sun.xml.internal.bind.v2.model.impl.RuntimeModelBuilder.getClassInfo(RuntimeModelBuilder.java:69)
    at com.sun.xml.internal.bind.v2.model.impl.ModelBuilder.getClassInfo(ModelBuilder.java:212)
    at com.sun.xml.internal.bind.v2.model.impl.RuntimeModelBuilder.getClassInfo(RuntimeModelBuilder.java:83)
    at com.sun.xml.internal.bind.v2.model.impl.RuntimeModelBuilder.getClassInfo(RuntimeModelBuilder.java:69)
    at com.sun.xml.internal.bind.v2.model.impl.ReferencePropertyInfoImpl.addAllSubtypes(ReferencePropertyInfoImpl.java:332)
    at com.sun.xml.internal.bind.v2.model.impl.ReferencePropertyInfoImpl.calcTypes(ReferencePropertyInfoImpl.java:158)
    at com.sun.xml.internal.bind.v2.model.impl.ReferencePropertyInfoImpl.getElements(ReferencePropertyInfoImpl.java:107)
    at com.sun.xml.internal.bind.v2.model.impl.RuntimeReferencePropertyInfoImpl.getElements(RuntimeReferencePropertyInfoImpl.java:56)
    at com.sun.xml.internal.bind.v2.model.impl.ReferencePropertyInfoImpl.ref(ReferencePropertyInfoImpl.java:98)
    at com.sun.xml.internal.bind.v2.model.impl.RuntimeReferencePropertyInfoImpl.ref(RuntimeReferencePropertyInfoImpl.java:60)
    at com.sun.xml.internal.bind.v2.model.impl.RuntimeReferencePropertyInfoImpl.ref(RuntimeReferencePropertyInfoImpl.java:40)
    at com.sun.xml.internal.bind.v2.model.impl.ModelBuilder.getClassInfo(ModelBuilder.java:260)
    at com.sun.xml.internal.bind.v2.model.impl.RuntimeModelBuilder.getClassInfo(RuntimeModelBuilder.java:88)
    at com.sun.xml.internal.bind.v2.model.impl.RuntimeModelBuilder.getClassInfo(RuntimeModelBuilder.java:69)
    at com.sun.xml.internal.bind.v2.model.impl.ModelBuilder.getClassInfo(ModelBuilder.java:212)
    at com.sun.xml.internal.bind.v2.model.impl.RuntimeModelBuilder.getClassInfo(RuntimeModelBuilder.java:83)
    at com.sun.xml.internal.bind.v2.model.impl.RuntimeModelBuilder.getClassInfo(RuntimeModelBuilder.java:69)
    at com.sun.xml.internal.bind.v2.model.impl.ModelBuilder.getTypeInfo(ModelBuilder.java:360)
    at com.sun.xml.internal.bind.v2.model.impl.ModelBuilder.getTypeInfo(ModelBuilder.java:375)
    at com.sun.xml.internal.bind.v2.runtime.JAXBContextImpl.getTypeInfoSet(JAXBContextImpl.java:439)
    at com.sun.xml.internal.bind.v2.runtime.JAXBContextImpl.<init>(JAXBContextImpl.java:277)
    at com.sun.xml.internal.bind.v2.runtime.JAXBContextImpl.<init>(JAXBContextImpl.java:124)
    at com.sun.xml.internal.bind.v2.runtime.JAXBContextImpl$JAXBContextBuilder.build(JAXBContextImpl.java:1123)
    at com.sun.xml.internal.bind.v2.ContextFactory.createContext(ContextFactory.java:147)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:498)
    at javax.xml.bind.ContextFinder.newInstance(ContextFinder.java:247)
    at javax.xml.bind.ContextFinder.newInstance(ContextFinder.java:234)
    at javax.xml.bind.ContextFinder.find(ContextFinder.java:462)
    at javax.xml.bind.JAXBContext.newInstance(JAXBContext.java:641)
    at javax.xml.bind.JAXBContext.newInstance(JAXBContext.java:584)
    at actividadxml3.ActividadXML3.main(ActividadXML3.java:139)
C:\Users\aitor\AppData\Local\NetBeans\Cache\8.2\executor-snippets\run.xml:53: Java returned: 1
BUILD FAILED (total time: 0 seconds)```

At this point i have been 2 days stuck here with no progress after searching documentation and forums, so i do like all of us always do when we cant find the answer and we feel overwhelmed: Open a stack overflow question to be burnt by the community.

Here is the main class of my program in which i create the object and fill all of its properties to hopefully when this works, generate the.xml

ActividadXML3.java

package actividadxml3;

import java.io.File;
import java.util.ArrayList;
import javax.xml.bind.JAXBContext;
import javax.xml.bind.JAXBException;
import javax.xml.bind.Marshaller;

/**
 *
 * @author Smock
 */
public class ActividadXML3 {

    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) {



        try{

            //crear y poblar objeto
            HealthTopic ht = new HealthTopic();
            //atributos HealthTopic
            ht.setMetaDesc("Un ataque cerebral hemorrágico ocurre cuando un vaso sanguíneo se rompe y sangra en el cerebro. Entérese sobre síntomas, diagnóstico y tratamientos ");
            ht.setTitle("Accidente cerebrovascular hemorrágico");
            ht.setUrl("https://medlineplus.gov/spanish/hemorrhagicstroke.html");
            ht.setId(6264);
            ht.setLanguage("Spanish");
            ht.setDateCreated("08/26/2015");
            //elementos valorados dentro de HealthTopic
            ArrayList<String> alsoCalled = new ArrayList<String>();
            alsoCalled.add("Accidente cerebral hemorrágico");
            alsoCalled.add("Ataque cerebral hemorrágico");
            alsoCalled.add("Derrame cerebral hemorrágico");
            ht.setAlsoCalled(alsoCalled);        
            ht.setFullSummary("https://medlineplus.gov/spanish/stroke.html");

            //GROUP
            Group gp = new Group();
            gp.setUrlGroup("https://medlineplus.gov/spanish/bloodheartandcirculation.html");
            gp.setIdGroup(7);
            gp.setValor("Sangre, corazón y circulación");
            ht.addObject(gp);
            Group gp2 = new Group();
            gp2.setUrlGroup("https://medlineplus.gov/spanish/brainandnerves.html");
            gp2.setIdGroup(14);
            gp2.setValor("Cerebro y nervios");
            ht.addObject(gp2);

            //LANGUAGE-MAPPED-TOPIC
            LanguageMappedTopic lmt = new LanguageMappedTopic();
            lmt.setUrlLanguage("https://medlineplus.gov/hemorrhagicstroke.html");
            lmt.setIdLanguage(6263);
            lmt.setLanguage("English");
            lmt.setValorLanguage("Hemorrhagic Stroke");
            ht.addObject(lmt);

            //PRIMARY-INSTITUTE
            PrimaryInstitute pi = new PrimaryInstitute();
            pi.setUrlInstitute("https://medlineplus.gov/spanish/nihinstitutes.html#NINDS");
            pi.setValor("Instituto Nacional de Trastornos Neurológicos y Accidentes Cerebrovasculares");
            ht.addObject(pi);

            //SITES
            Site s1 = new Site();
            s1.setTitle("Alta tras accidente cerebrovascular");
            s1.setUrl("https://medlineplus.gov/spanish/ency/patientinstructions/000132.htm");
            s1.setLanguageMappedUrl("https://medlineplus.gov/ency/patientinstructions/000132.htm");
            ArrayList<String>info1 = new ArrayList<String>();
            info1.add("Mas informacion");
            info1.add("Spanish/Español");
            info1.add("NON_DISPLAY (Patient Handout");
            s1.setInformationCategory(info1);
            s1.setOrganization("Enciclopedia Médica");
            ht.addObject(s1);

            Site s2 = new Site();
            s2.setTitle("Angiopatia amiloide cerebral");
            s2.setUrl("https://medlineplus.gov/spanish/ency/article/000719.htm");
            s2.setLanguageMappedUrl("https://medlineplus.gov/ency/article/000719.htm");
            ArrayList<String>info2 = new ArrayList<String>();
            info2.add("Mas informacion");
            info2.add("Spanish/Español");
            s2.setInformationCategory(info2);
            s2.setOrganization("Enciclopedia Médica");
            ht.addObject(s2);

            Site s3 = new Site();
            s3.setTitle("Hablemos sobre el ataque hemorrágico al cerebro");
            s3.setUrl("https://www.stroke.org/-/media/stroke-files/spanish-resources/ltas-hemorrhagic-stroke.pdf");
            s3.setLanguageMappedUrl("https://www.stroke.org/en/about-stroke/types-of-stroke/hemorrhagic-strokes-bleeds");
            ArrayList<String>info3 = new ArrayList<String>();
            info3.add("Mas informacion");
            info3.add("Spanish/Español");
            s3.setInformationCategory(info3);
            s3.setOrganization("Asociación Americana del Corazón");
            s3.setStandardDescription("PDF");
            ht.addObject(s3);

            Site s4 = new Site();
            s4.setTitle("Hemorragia subaracnoidea");
            s4.setUrl("https://medlineplus.gov/spanish/ency/article/000701.htm");
            s4.setLanguageMappedUrl("https://medlineplus.gov/ency/article/000701.htm");
            ArrayList<String>info4 = new ArrayList<String>();
            info4.add("Mas informacion");
            info4.add("Spanish/Español");
            s4.setInformationCategory(info4);
            s4.setOrganization("Enciclopedia Médica");
            ht.addObject(s4);

            Site s5 = new Site();
            s5.setTitle("Prevención de un accidente cerebrovascular");
            s5.setUrl("https://medlineplus.gov/spanish/ency/patientinstructions/000678.htm");
            s5.setLanguageMappedUrl("https://medlineplus.gov/ency/patientinstructions/000678.htm");
            ArrayList<String>info5 = new ArrayList<String>();
            info5.add("Mas informacion");
            info5.add("Spanish/Español");
            info5.add("NON-DISPLAY (Patient Handout)");
            s5.setInformationCategory(info5);
            s5.setOrganization("Enciclopedia Médica");
            ht.addObject(s5);


            //System.out.println(ht.toString());

            //Error en jaxbConext indexOutofBoundsException en l asiguiente linea  
            System.out.println("Inicio creacion objeto JAXB");
            JAXBContext jc = JAXBContext.newInstance(HealthTopic.class);
            System.out.println("Ojala algun dia lea esto en pantalla");

            Marshaller mar = jc.createMarshaller();
            mar.setProperty(Marshaller.JAXB_FORMATTED_OUTPUT, true);
            File xml = new File("health-topic.xml");
            mar.marshal(ht, xml);


        }catch(JAXBException ex){
            System.out.println(ex);
            System.out.println(ex.getMessage());
        }
    }

}

Im pretty sure you will need my HealthTopic.class to help me, i dont think you need the rest of the subclasses but if you do, let me know and i will gladly edit and post them.

HealthTopic.class

package actividadxml3;

import java.util.ArrayList;
import javax.xml.bind.annotation.*;

/**
 *
 * @author Smock
 */
@XmlRootElement(name="health-topic")
@XmlAccessorType(XmlAccessType.FIELD)//todos los campos son automaticamente generados
public class HealthTopic {

    @XmlAttribute(name = "meta-desc")
    private String metaDesc;

    @XmlAttribute(name = "title")
    private String title;

    @XmlAttribute(name = "url")
    private String url;

    @XmlAttribute(name = "id")
    private int id;

    @XmlAttribute(name = "language")
    private String language;

    @XmlAttribute(name = "date-created")
    private String dateCreated;


    @XmlElement(name = "also-called")
    private ArrayList<String> alsoCalled;

    //@XmlMixed
    @XmlElement(name="full-summary")
    private String fullSummary;

    @XmlMixed
    @XmlElementRefs({
        @XmlElementRef(type = Group.class),
        @XmlElementRef(type = LanguageMappedTopic.class),
        @XmlElementRef(type = PrimaryInstitute.class),
        @XmlElementRef(type = Site.class)
    })

    private ArrayList<Object> objects = new ArrayList();

    public HealthTopic() {
    }

    public HealthTopic(String metaDesc, String title, String url, int id, String language, String dateCreated, ArrayList<String> alsoCalled, String fullSummary, ArrayList<Object> objects) {
        this.metaDesc = metaDesc;
        this.title = title;
        this.url = url;
        this.id = id;
        this.language = language;
        this.dateCreated = dateCreated;
        this.alsoCalled = alsoCalled;
        this.fullSummary = fullSummary;
        this.objects = objects;
    }

    public String getMetaDesc() {
        return metaDesc;
    }


    public void setMetaDesc(String metaDesc) {
        this.metaDesc = metaDesc;
    }

    public String getTitle() {
        return title;
    }

    public void setTitle(String title) {
        this.title = title;
    }

    public String getUrl() {
        return url;
    }

    public void setUrl(String url) {
        this.url = url;
    }

    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    public String getLanguage() {
        return language;
    }

    public void setLanguage(String language) {
        this.language = language;
    }

    public String getDateCreated() {
        return dateCreated;
    }

    public void setDateCreated(String dateCreated) {
        this.dateCreated = dateCreated;
    }

    public ArrayList<String> getAlsoCalled() {
        return alsoCalled;
    }

    public void setAlsoCalled(ArrayList<String> alsoCalled) {
        this.alsoCalled = alsoCalled;
    }

    public String getFullSummary() {
        return fullSummary;
    }

    public void setFullSummary(String fullSummary) {
        this.fullSummary = fullSummary;
    }

    public ArrayList<Object> getObjects() {
        return objects;
    }

    public void setObjects(ArrayList<Object> objects) {
        this.objects = objects;
    }



    public void addObject(Object object){
        objects.add(object);
    }

    @Override
    public String toString() {
        return "HealthTopic{" + "metaDesc=" + metaDesc + ", title=" + title + ", url=" + url + ", id=" + id + ", language=" + language + ", dateCreated=" + dateCreated + ", alsoCalled=" + alsoCalled + ", fullSummary=" + fullSummary + ", objects=" + objects + '}';
    }



}

It would mean a lot to me if somebody was able to find a solution to this or point me in the right direction, since I've already lost too much time in this with no progress and i would feel bad leaving this without a fix.

EDIT: Adding the rest of the classes since it may help

Group.java

package actividadxml3;

import javax.xml.bind.annotation.*;

/**
 *
 * @author Smock
 */
@XmlRootElement(name="group")
@XmlAccessorType(XmlAccessType.PROPERTY)//todos los getters/setter se generan automaticamente
public class Group {

    private String urlGroup;

    private int idGroup;

    //implementar valor del group
    private String valor;

    public Group() {
    }

    public Group(String urlGroup, int idGroup, String valor) {
        this.urlGroup = urlGroup;
        this.idGroup = idGroup;
        this.valor = valor;
    }

    public String getUrlGroup() {
        return urlGroup;
    }
    @XmlAttribute(name="url")
    public void setUrlGroup(String urlGroup) {
        this.urlGroup = urlGroup;
    }

    public int getIdGroup() {
        return idGroup;
    }

    @XmlAttribute(name="id")
    public void setIdGroup(int idGroup) {
        this.idGroup = idGroup;
    }

    public String getValor() {
        return valor;
    }

    //no hace falta anotaciones prueba
    public void setValor(String valor) {
        this.valor = valor;
    }


    @Override
    public String toString() {
        return "Group{" + "urlGroup=" + urlGroup + ", idGroup=" + idGroup + ", valor=" + valor + '}';
    }


}

LanguageMappedTopic.java

package actividadxml3;

import javax.xml.bind.annotation.*;

/**
 *
 * @author Smock
 */
@XmlRootElement(name="language-mapped-topic")
@XmlAccessorType(XmlAccessType.NONE) // nada se genera a no ser que se anote
public class LanguageMappedTopic {

    @XmlAttribute(name="url")
    private String urlLanguage;

    @XmlAttribute(name="id")
    private int idLanguage;

    @XmlAttribute(name="language")
    private String language;

    @XmlValue
    private String valorLanguage;


    public LanguageMappedTopic() {
    }

    public LanguageMappedTopic(String urlLanguage, int idLanguage, String language, String valorLanguage) {
        this.urlLanguage = urlLanguage;
        this.idLanguage = idLanguage;
        this.language = language;
        this.valorLanguage = valorLanguage;
    }

    public String getUrlLanguage() {
        return urlLanguage;
    }

    public void setUrlLanguage(String urlLanguage) {
        this.urlLanguage = urlLanguage;
    }

    public int getIdLanguage() {
        return idLanguage;
    }

    public void setIdLanguage(int idLanguage) {
        this.idLanguage = idLanguage;
    }

    public String getLanguage() {
        return language;
    }

    public void setLanguage(String language) {
        this.language = language;
    }

    public String getValorLanguage() {
        return valorLanguage;
    }

    public void setValorLanguage(String valorLanguage) {
        this.valorLanguage = valorLanguage;
    }

    @Override
    public String toString() {
        return "LanguageMappedTopic{" + "urlLanguage=" + urlLanguage + ", idLanguage=" + idLanguage + ", language=" + language + ", valorLanguage=" + valorLanguage + '}';
    }



}

PrimaryInstitute.java

package actividadxml3;

import javax.xml.bind.annotation.*;

/**
 *
 * @author Smock
 */
@XmlRootElement(name="primary-institute")
@XmlAccessorType(XmlAccessType.PUBLIC_MEMBER)//se genera todo lo declarado publico
public class PrimaryInstitute {


    private String urlInstitute;

    private String valor;

    public PrimaryInstitute() {
    }

    public PrimaryInstitute(String urlInstitute, String valor) {
        this.urlInstitute = urlInstitute;
        this.valor = valor;
    }

    public String getUrlInstitute() {
        return urlInstitute;
    }

    @XmlAttribute(name="url")
    public void setUrlInstitute(String urlInstitute) {
        this.urlInstitute = urlInstitute;
    }

    public String getValor() {
        return valor;
    }

    @XmlValue
    public void setValor(String valor) {
        this.valor = valor;
    }

    @Override
    public String toString() {
        return "PrimaryInstitute{" + "urlInstitute=" + urlInstitute + ", valor=" + valor + '}';
    }


}

** Site.class**

package actividadxml3;

import java.util.ArrayList;
import javax.xml.bind.annotation.*;
/**
 *
 * @author Smock
 */
@XmlRootElement(name="site")
public class Site {

    @XmlAttribute(name="title")
    private String title;

    @XmlAttribute(name="url")
    private String url;

    @XmlAttribute(name="language-mapped-url")
    private String languageMappedUrl;

    @XmlMixed
    @XmlElement(name="information-category")
    private ArrayList<String> informationCategory;

    @XmlElement(name="organization")
    private String organization;

    @XmlElement(name="standard-description",required=false)
    private String standardDescription;

    public Site() {
    }

    public Site(String title, String url, String languageMappedUrl, ArrayList<String> informationCategory, String organization, String standardDescription) {
        this.title = title;
        this.url = url;
        this.languageMappedUrl = languageMappedUrl;
        this.informationCategory = informationCategory;
        this.organization = organization;
        this.standardDescription = standardDescription;
    }

    public String getTitle() {
        return title;
    }

    public void setTitle(String title) {
        this.title = title;
    }

    public String getUrl() {
        return url;
    }

    public void setUrl(String url) {
        this.url = url;
    }

    public String getLanguageMappedUrl() {
        return languageMappedUrl;
    }

    public void setLanguageMappedUrl(String languageMappedUrl) {
        this.languageMappedUrl = languageMappedUrl;
    }

    public ArrayList<String> getInformationCategory() {
        if(informationCategory == null){
            informationCategory = new ArrayList<>();
        }
        return informationCategory;
    }

    public void setInformationCategory(ArrayList<String> informationCategory) {
        this.informationCategory = informationCategory;
    }

    public String getOrganization() {
        return organization;
    }

    public void setOrganization(String organization) {
        this.organization = organization;
    }

    public String getStandardDescription() {
        return standardDescription;
    }

    public void setStandardDescription(String standardDescription) {
        this.standardDescription = standardDescription;
    }

    @Override
    public String toString() {
        return "Site{" + "title=" + title + ", url=" + url + ", languageMappedUrl=" + languageMappedUrl + ", informationCategory=" + informationCategory + ", organization=" + organization + ", standardDescription=" + standardDescription + '}';
    }


}

This should be all. As somebody told, i tried modifying the getters for ArrayLists in case they were null so that i return a newly created ArrayList, but im still getting the same error.

I dont think there is more code of my program to show but let me know if im wrong.

Answer 1

in HealthTopic class, change your getter for list. if list is null then create object and then only return list like below (change for all list):

public ArrayList<String> getAlsoCalled() {
        if (alsoCalled == null) {
          alsoCalled = new ArrayList<>();
        } 
        return alsoCalled;
    }

Answer 2

Problem is in your Site class, please do the below changes to your Site class

1. Add

   @XmlAccessorType(XmlAccessType.FIELD)

2. Remove @XmlMixed annotation for informationCategory variable

   // @XmlMixed @XmlElement(name="information-category") private ArrayList<String> informationCategory;