java windowbuilder can't add bindings for columns
<p>I am trying to bind an ArrayList of objects to a jTable using Eclipse WindowsBuilder. 
But Create Data Binding screen doesn't show "Add" button, as is shown in eclipse tutorial.</p>

<p>Here is my object:</p>

<pre><code>public class EventDTO implements Serializable {
private static final long serialVersionUID = 1L;
private Integer id;
private String comment;
private Date date;
private String message;
private Set&lt;EventGiftDTO&gt; eventGifts;
private Set&lt;EventPersonDTO&gt; participants;
private Set&lt;EventProductDTO&gt; eventProducts;
private PersonDTO initiator;
private EventTypeDTO eventType;

public EventDTO() {
}

public Integer getId() {
    return this.id;
}

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

public String getComment() {
    return this.comment;
}

public void setComment(String comment) {
    this.comment = comment;
}

public Date getDate() {
    return this.date;
}

public void setDate(Date date) {
    this.date = date;
}

public String getMessage() {
    return this.message;
}

public void setMessage(String message) {
    this.message = message;
}

public Set&lt;EventGiftDTO&gt; getGifts() {
    return eventGifts;
}

public void setGifts(Set&lt;EventGiftDTO&gt; eventGifts) {
    this.eventGifts = eventGifts;
}

public boolean addGift(EventGiftDTO eg){
    if(eventGifts==null)eventGifts=new HashSet&lt;&gt;();
    return eventGifts.add(eg);
}

public boolean removeGift(EventGiftDTO adv){
    if(eventGifts==null) return true;
    return eventGifts.remove(adv);
}

public Set&lt;EventPersonDTO&gt; getParticipants() {
    return participants;
}

public void setParticipants(Set&lt;EventPersonDTO&gt; participants) {
    this.participants = participants;
}

public boolean addParticipant(EventPersonDTO p){
    if(participants==null) participants=new HashSet&lt;&gt;();
    return participants.add(p);
}

public boolean removeParticipant(EventPersonDTO p){
    if(participants==null) return true;
    return participants.remove(p);
}

public Set&lt;EventProductDTO&gt; getProducts() {
    return eventProducts;
}

public void setProducts(Set&lt;EventProductDTO&gt; eventProducts) {
    this.eventProducts = eventProducts;
}

public boolean addProduct(EventProductDTO pr){
    if(eventProducts==null) eventProducts=new HashSet&lt;&gt;();
    return eventProducts.add(pr);
}

public boolean removeProduct(EventProductDTO pr){
    if(eventProducts==null) return true;
    return eventProducts.remove(pr);
}

public PersonDTO getInitiator() {
    return initiator;
}

public void setInitiator(PersonDTO initiator) {
    this.initiator = initiator;
}

public EventTypeDTO getEventType() {
    return eventType;
}

public void setEventType(EventTypeDTO eventType) {
    this.eventType = eventType;
}
</code></pre>

<p>}</p>

<p>and here is my Create Data Binding screen:</p>

<p><a href="http://i.stack.imgur.com/iyHRT.png" rel="nofollow">Create Data Binding</a></p>

<p>Any help would be appreciated!</p>