Thursday, July 31, 2014

Re: GWT, Hibernate and a many to many relationship

The basic answer is you cannot. You will need to transform the Hibernate object into a POJO to make it serial, this is a requirement of any object being passed between the client and the server in GWT.

On Jul 30, 2014, at 5:07 AM, Peter S. <> wrote:

Hey all,

after searching the complete web for a solution and didn't find one, I will try to share my problem with you ;)..

Well I have the famous failure with GWT and Hibernate:

java.lang.RuntimeException: Type 'org.hibernate.collection.PersistentSet' was not included in the set of types which can be serialized by this SerializationPolicy or its Class object could not be loaded. For security purposes, this type will not be serialized.: instance = []

I have a hbm.xml file where Hibernate generates an Entity.

<class abstract="false"
        <meta attribute="extends">net.sf.gilead.pojo.gwt.LightEntity</meta>  <!-- This was a try but also didn't work. so that line is not implemented in general -->
        <meta attribute="implements">com.egrima.webinfotools.common.entity.BasisEntity</meta>
        <id column="ID" name="id" type="java.lang.Long">
            <generator class="sequence">
                <param name="sequence">SEQ_WITPOIS</param>

        <property column="ZALTKN" generated="never" lazy="false"
            name="zaltkn" length="6" type="java.lang.String" />
        <property column="NAME" generated="never" lazy="false" name="name"
            length="255" type="java.lang.String" />
        <property column="ADDRESS" generated="never" lazy="false"
            name="address" length="512" type="java.lang.String" />
        <property column="LONGITUDE" generated="never" lazy="false"
            name="longitude" type="java.lang.Double" />
        <property column="LATITUDE" generated="never" lazy="false"
            name="latitude" type="java.lang.Double" />
        <property column="ANL_DAT_ZEIT" generated="never" lazy="false"
            name="createdDate" type="java.util.Date" />
        <property column="AEN_DAT_ZEIT" generated="never" lazy="false"
            name="changedDate" type="java.util.Date" />
        <property column="TERM" generated="never" name="hostname"
            length="12" type="java.lang.String" />
        <property column="BEN" generated="never" name="username"
            length="8" type="java.lang.String" />

        <many-to-one name="category" foreign-key="fk_poi_category" cascade="all"
            column="category_id" lazy="false"    class="com.egrima.webinfotools.common.entity.generated.PointOfInterestCategory" />
        <one-to-one name="poiNameTranslation" lazy="false" cascade="all"  foreign-key="fk_witpoi_translation" class="com.egrima.webinfotools.common.entity.generated.PointOfInterestTranslation"/>
        <set name="attributes" inverse="true" table="witpoi_attribute" lazy="false" cascade="all" fetch="select">
          <key column="POI_ID"/>
            <many-to-many  class="com.egrima.webinfotools.common.entity.generated.PointOfInterestAttribute" column="ATTRIBUTE_ID"   fetch="join"/>

The generated Class looks like this:

package com.egrima.webinfotools.common.entity;
// Generated 30.07.2014 10:56:07 by Hibernate Tools 3.2.2.GA

import com.egrima.webinfotools.common.entity.generated.PointOfInterestAttribute;
import com.egrima.webinfotools.common.entity.generated.PointOfInterestCategory;
import com.egrima.webinfotools.common.entity.generated.PointOfInterestTranslation;
import java.util.Date;
import java.util.HashSet;
import java.util.Set;

 * PointOfInterest generated by hbm2java

public class PointOfInterest  implements com.egrima.webinfotools.common.entity.BasisEntity, {

    private static final long serialVersionUID = 42L;

     private Long id;
     private String zaltkn;
     private String name;
     private String address;
     private Double longitude;
     private Double latitude;
     private Date createdDate;
     private Date changedDate;
     private String hostname;
     private String username;
     private PointOfInterestCategory category;
     private PointOfInterestTranslation poiNameTranslation;
     private Set<PointOfInterestAttribute> attributes = new HashSet<PointOfInterestAttribute>(0);

    public PointOfInterest() {

    public PointOfInterest(String zaltkn, String name, String address, Double longitude, Double latitude, Date createdDate, Date changedDate, String hostname, String username, PointOfInterestCategory category, PointOfInterestTranslation poiNameTranslation, Set<PointOfInterestAttribute> attributes) {
       this.zaltkn = zaltkn; = name;
       this.address = address;
       this.longitude = longitude;
       this.latitude = latitude;
       this.createdDate = createdDate;
       this.changedDate = changedDate;
       this.hostname = hostname;
       this.username = username;
       this.category = category;
       this.poiNameTranslation = poiNameTranslation;
       this.attributes = attributes;

    public Long getId() {
        return id;
    public void setId(Long id) { = id;
    public String getZaltkn() {
        return zaltkn;
    public void setZaltkn(String zaltkn) {
        this.zaltkn = zaltkn;
    public String getName() {
        return name;
    public void setName(String name) { = name;
    public String getAddress() {
        return address;
    public void setAddress(String address) {
        this.address = address;
    public Double getLongitude() {
        return longitude;
    public void setLongitude(Double longitude) {
        this.longitude = longitude;
    public Double getLatitude() {
        return latitude;
    public void setLatitude(Double latitude) {
        this.latitude = latitude;
    public Date getCreatedDate() {
        return createdDate;
    public void setCreatedDate(Date createdDate) {
        this.createdDate = createdDate;
    public Date getChangedDate() {
        return changedDate;
    public void setChangedDate(Date changedDate) {
        this.changedDate = changedDate;
    public String getHostname() {
        return hostname;
    public void setHostname(String hostname) {
        this.hostname = hostname;
    public String getUsername() {
        return username;
    public void setUsername(String username) {
        this.username = username;
    public PointOfInterestCategory getCategory() {
        return category;
    public void setCategory(PointOfInterestCategory category) {
        this.category = category;
    public PointOfInterestTranslation getPoiNameTranslation() {
        return poiNameTranslation;
    public void setPoiNameTranslation(PointOfInterestTranslation poiNameTranslation) {
        this.poiNameTranslation = poiNameTranslation;
    public Set<PointOfInterestAttribute> getAttributes() {
        return attributes;
    public void setAttributes(Set<PointOfInterestAttribute> attributes) {
        this.attributes = attributes;


In our project we also make use of GILEAD and this description  they also mention the problem I have. But how does this work together with code-generation. Because when I make use of Gilead I can not generate the class. And when I uncomment the class in the hbm.xml the mapping won't work. How can I solve this problem? I really have no clue anymore.. please help me :)

Thank you!
Greetz Peter

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