jstl - forEach, bean having a list of beans as property

Question

I have a bean called Experiment which has a property that is a arraylist of beans of a type called Assay.

In a jsp I want to iterate over the list of assays stored in an Experiment bean, which I try to do by doing this:

                <c:forEach items="${exp.assays}" var="ay">
                    <tr><td>${ay.decision}</td><td>${ay.comment}</td></tr>
                </c:forEach>

'descision' and 'comment' are properties of the Assay bean.

But this doesn't work. I get the error:

SEVERE: javax.el.PropertyNotFoundException: The class 'beans.Experiment' does not have the property 'decision'.

as if the items in the 'exp.assays' list where of bean type Experiment and not of Assay as I would expect.

So I tried accessing Experiment property (eid, which I know I can access by directly writing ${exp.eid}) in the forEach-loop instead, like this:

                <c:forEach items="${exp.assays}" var="ay">
                    <tr><td>${ay.eid}</td></tr>
                </c:forEach>

but then I got the error message:

SEVERE: javax.el.PropertyNotFoundException: The class 'beans.Assay' does not have the property 'eid'. 

Anyone who knows what is going on or how I could fix it?

The full bean code is pretty long but here are the parts that I think are relevant here

Experiment:

public class Experiment extends dataItem implements Serializable {

    private String eid;
    private List<Assay> assays = new ArrayList();

    public String getEid() {
        return eid;
    }

    public void setEid(String id) {
        eid = id;
    }  

    public List<Assay> getAssays() {
        return assays;
    }

    public void setAssays(List<Assay> assays) {
        this.assays = assays;
    }

}

And Assay:

public class Assay extends dataItem implements Serializable {

    private Integer id;
    private stock antigen;
    private String decision;
    private String comment;
    private String freeAb;    
    private List<AssayData> data;
    private List<conjugate> conjugates = new ArrayList();

    public List<conjugate> getConjugates() {
        return conjugates;
    }

    public void setConjugates(List<conjugate> conjugates) {
        this.conjugates = conjugates;
    }   

    public Integer getId() {
        return id;
    }

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

    public stock getAntigen() {
        return antigen;
    }

    public void setAntigen(String id) {
        stock s = new stock();
        s.setSID(id);

        this.antigen = s;
    }

    public String getDecision() {
        return decision;
    }

    public void setDecision(String decision) {
        this.decision = decision;
    }

    public String getComment() {
        return comment;
    }

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

    public String getFreeAb() {
        return freeAb;
    }

    public void setFreeAb(String freeAb) {
       this.freeAb = freeAb;
    }

    public List<AssayData> getData() {
       return data;
    }

    public void setData(List<AssayData> data) {
       this.data = data;
    }   
}

Solution

I have just attempted to replicate the issue that you are having and find that it works without error. Here is my code:

The Assay class:

 public class Assay {

     private String decision;
     private String comment;    

     Assay(){}

     Assay(String decision, String comment){
         setComment(comment);
         setDecision(decision);
     }

     public String getComment() {
         return comment;
     }
     public void setComment(String comment) {
         this.comment = comment;
     }
     public String getDecision() {
         return decision;
     }
     public void setDecision(String decision) {
         this.decision = decision;
     }  
 }

The Experiment class:

 public class Experiment {

     private ArrayList<Assay> assays = new ArrayList<Assay>();

     public Experiment() {      
         assays.add(new Assay("c1","d1"));
         assays.add(new Assay("c2","d2"));          
     }

     public ArrayList<Assay> getAssays() {
         return assays;
     }

         public void setAssays(ArrayList<Assay> assays) {
             this.assays = assays;
         }  
 }

The JSP:

 <%
      Experiment e = new Experiment();
      pageContext.setAttribute("exp", e);
 %>

 <c:forEach items="${exp.assays}" var="ay">
      <tr><td>${ay.decision}</td><td>${ay.comment}</td></tr>
 </c:forEach>

The output is: c1d1 c2d2

Compare what I have done above with your code and see if you can identify any differences. If you continue to have problems post your code here.