Dynamic table not displaying.

[Vic Hood]

Hi all ,
Im trying to dynamically populate a list of tables based on the selection in a dropdown .Im using a list of beans to store the values that I obtain from the database.However, no matter what selection I make , in the dropdown the the display only shows that there are no records to display> im also using a displaytag library here , to aid with the formatting of my table . Im pasting the code from my jsp that I use below to generate the table.

  <display:table name="${dao.domList}" pagesize="2" id ="dl" export="true" >     
       <display:column property="code" sortable="true"/>     
       <display:column property="description" sortable="true" />    
       <display:column  property="statusActive" sortable="true" title="IsActive?"/>   
       <display:column  property="statusEdit" title="IsEdit?" sortable="true"/>  
      
       	<display:column title="Edit" media="html">  
       <c:set var="id" value="${dl.objid}" />  
        <a href="POC.jsp?${id}" onclick="selectobjID(${id})">Edit </a>   
    	</display:column>  

The servlet code ie. used to fetch the records.Im being able to see the records through logging here though.

ublic void setDomList(ArrayList domList) {
	this.domList = domList;
}
public List getDomList()throws Exception {

if(domainType_Oid!=0 && domainType_Oid!=-1){
int dt_oid=domainType_Oid;
Connection con = null;
PreparedStatement stmt = null;
ResultSet rs = null;
DomainBean domainBean=null;
System.out.println("The domaintype being accessed by listDomain has dt-oid="+dt_oid);
System.out.println("Listing records in DAO");
List<DomainBean> domList = new ArrayList<DomainBean>();
try {
	con= DBConnector.getConnection();
	if (con != null){
		System.out.println("Connected");
	String query= "SELECT OBJECTID,CODE,DESCRIPTION,ISEDITABLE, ISACTIVE FROM DOMAIN WHERE DOMAINTYPE_OID='"+dt_oid+"' ORDER BY DOMAINTYPE_OID,OBJECTID " ;
	System.out.println(query);
	stmt = con.prepareStatement(query);
	
	rs = stmt.executeQuery();
	while (rs.next()){
		System.out.println("In While");
		domainBean= new DomainBean();
		domainBean.setObjid(rs.getInt("OBJECTID"));
		System.out.println("The value of Objid"+domainBean.getObjid());
		domainBean.setCode(rs.getString("CODE"));
		if (rs.getString("ISACTIVE").equals("1"))
			domainBean.setstatusActive("Yes");
		if (rs.getString("ISACTIVE").equals("0"))
			domainBean.setstatusActive("No");
		if (rs.getString("ISEDITABLE").equals("1"))
			domainBean.setstatusEdit("Yes");
		if (rs.getString("ISEDITABLE").equals("0"))
			domainBean.setstatusEdit("No");
		domainBean.setDescription(rs.getString("DESCRIPTION"));
		System.out.println("The value of Code"+domainBean.getCode());
		System.out.println("The value of Description"+domainBean.getDescription());
		System.out.println("The value of Status Active"+domainBean.getstatusActive());
		domList.add(domainBean);
	}
//		System.out.println("Objectid in DAO-ListDomain  "+domainBean.getObjid());
			}
	}catch (SQLException sqe) {
		sqe.printStackTrace();

	} finally {
		DBConnector.closeResultSet(rs);
		DBConnector.closeStatement(stmt);
		DBConnector.closeConnection(con);
	}
		
}
return domList;
}

Any pointers as to where i could be going wrong?

[Robin John]

you say that the dao.domList is fetched from the database and is populated. so now remove all the code from the jsp and put a c:forEach tag and see the contents of the ${dao.domList}, if that is okay.. then display tag should not give you that error message.

[Vic Hood]

HI Robin,
Thanks for replying. as you suggested i did try the following code snippet To replace the display table tag

 	
 	   <table>
 	   <c:if test="${dao.domList != null}" > 
      <c:forEach var="dl"  items="${dao.domList}">
        <tr>
          <td>${dl.code}</td>
          <td>${dl.description}</td>
        </tr>
      </c:forEach>
      </c:if>
    </table>
     

However, there was no change in the situation , the records are being fetched in the DAO , but not being displayed in the front end/jsp . Also, the condition is the same even if the c:if test is removed .Any pointers to what i could be missing??
Thanks.

[Robin John]

Vic Hood wrote:
However, there was no change in the situation , the records are being fetched in the DAO , but not being displayed in the front end/jsp . Also, the condition is the same even if the c:if test is removed .Any pointers to what i could be missing??

so you have the answer... the dao object is not being set to the request. put an else tag in the page.. if it enters that, then its null !

[Vic Hood]

hi Robin ,
Thanks for replying !Yes you are right , the dao object is not being set , any ideas on how i could go about in fixing this?
EDIT: I did try the else part using an other if , and it executed .

[Robin John]

this Link

and this Link might help you...


Also go through Bear's Article Here

[Vic Hood]

Thanks for the reply Robin! However, im not using a session here , the dao and domain objects are set only in the request . I dont want to use a session here , are you saying that its not possible to retrieve the contents using the request scope ?

[Robin John]

Yes, since you are not using any frameworks like struts/struts2 which make the action forms / bean properties automatically available to the jsp page, you have to set it 'somewhere'. Decide for yourself which scope to use. Use request.setAttribute to pass objects.. Set the object in the request if you dont want to use the session scope... but do retrieve them in your jsp's using EL tags and NOT scriptlets !!

[Vic Hood]

Thanks for replying John!
Im using a list of beans to populate the table , are you suggesting that i set this list-'domList' in the request? The reason I ask is , im using another list of beans to generate the drop down , but it works fine without being set in the request.

EDIT- Tried setting it in the request, but doesnt work:(.also , i ve used only EL tags and no scriptlets

[Robin John]

how are you setting it ? use proper getters and setters for getting objects "case and spelling" matters a lot.

paste some code.

[Vic Hood]

Okay , well if you mean the DAO class , im using a getter and setter of the following nature ..

public ArrayList domList;
public void setDomList(ArrayList domList) {
			this.domList = domList;
		}
public List getDomList()throws Exception {
//code to get the domList
...
...
return domList;

In my bean class , DomainBean .java

package com.jspcrud.bean;



import java.io.Serializable;

import java.util.ArrayList;

public class DomainBean implements Serializable  {
/**
	 * 
	 */
	private static final long serialVersionUID = 1L;
private String domainType;
private String  code;
private String description;

private int domainTypeOid;
private boolean active;/*active and edit are meant to be used only in the servlet after obtaining the value of checkbox using statusActive and statusEdit*/
private boolean edit;
@SuppressWarnings("rawtypes")
private ArrayList domList;
private String statusActive;
private String statusEdit;
private String message;
private int  objid;// to get link ..

ArrayList<DomainBean> dtList = new ArrayList<DomainBean>();
	

	public DomainBean(){}
	
	
	public void setDomainType(String domainType) {
		this.domainType = domainType;	}

	public String getDomainType() {
	return domainType;
	}

	public void setCode(String code) {
		this.code = code;
	}

	public String getCode() {
		return code;
	}

	public void setDescription(String description) {
		this.description = description;
	}

	public String getDescription() {
		return description;
	}

	


	@SuppressWarnings("rawtypes")
	public ArrayList getDomList() {
		return domList;
	}

	@SuppressWarnings("rawtypes")
	public void setDomList(ArrayList domList) {
		this.domList = domList;
	}

	public void setDomainTypeOid(int dt_oid) {
		this.domainTypeOid = dt_oid;
	System.out.println(" DomainBean.java--domainTypeOid is "+dt_oid);
	
	}

	public int getDomainTypeOid() {
		return domainTypeOid;
	}

	public void setObjid(int objid) {
		System.out.println("The value of objid in the bean  "+objid);
		this.objid = objid;
	}

	public int getObjid() {
		return objid;
	}

	public void setstatusActive(String statusActive) {
		this.statusActive = statusActive;
	}

	public String getstatusActive() {
		//System.out.println("Status of active check"+statusActive);
		return statusActive;
		
	}

	public void setstatusEdit(String statusEdit) {
		this.statusEdit = statusEdit;
	}

	public String getstatusEdit() {
		return statusEdit;
	}

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

	public String getMessage() {
		return message;
	}

	

	
	public ArrayList<DomainBean> getDtList() {
		return dtList;
	}

	public void setDtList(ArrayList<DomainBean> dtList) {
		this.dtList = dtList;
	}


	public void setActive(boolean active) {
		this.active = active;
	}


	public boolean getActive() {
		return active;
	}


	public void setEdit(boolean edit) {
		this.edit = edit;
	}


	public boolean getEdit() {
		return edit;
	}
	
	

}

[Robin John]

You have in your servlet code ->

 @SuppressWarnings("rawtypes")
 public ArrayList dtList;// List to store the domaintype beans.
 @SuppressWarnings("rawtypes")
 public ArrayList domList;

and later in your code in getters and setters ->

dtList = new ArrayList<DomainTypeBean>() ;      // in getDtList() you have set the instance variable.
List<DomainBean> domList = new ArrayList<DomainBean>();  // in getDomList() you have created a local variable.

just try changing that to "domList = new ArrayList<DomainBean>(); // set it to instance variable.

[Vic Hood]

I tried that too , werent you suggesting something like this?

...
public void setDomList(ArrayList domList) {
			this.domList = domList;
		}
		public List getDomList()throws Exception {

		if(domainType_Oid!=0 && domainType_Oid!=-1){
		int dt_oid=domainType_Oid;
		Connection con = null;
		PreparedStatement stmt = null;
		ResultSet rs = null;
		DomainBean domainBean=null;
		System.out.println("The domaintype being accessed by listDomain has dt-oid="+dt_oid);
		System.out.println("Listing records in DAO");
		domList = new ArrayList<DomainBean>();// <--Here??
		try {
			con= DBConnector.getConnection();
			if (con != null){
				System.out.println("Connected");
			String query= "SELECT OBJECTID,CODE,DESCRIPTION,ISEDITABLE, ISACTIVE FROM DOMAIN WHERE DOMAINTYPE_OID='"+dt_oid+"' ORDER BY DOMAINTYPE_OID,OBJECTID " ;
			System.out.println(query);
			....

However , there is no change

[Robin John]

as I have asked before, how are you setting it to the request ? the dao object ? or are you setting specific variables... ?

[Vic Hood]

Yep that was the right question! I was overseeing something simple , I guess i tried accessing the bean through a dao object dao.domList however when I changed that to plain domList , it showed a corresponding list of records.(I wonder why this is happening because I use a dao object to generate another list dtList for a dropdown of the form dao.dtList , then wonder why the same doesnt apply here? )
However , here too when i try to implement pagination using the display tag , only the records in the first page are displayed , when i click on the next page it returns an empty result . Ive tried changing the no. of records in the page however only the ones in the first page are displayed and not the rest. Any clues as to where I could be going wrong?
Thanks for replying.

[Robin John]

Vic Hood wrote:.....
However , here too when i try to implement pagination using the display tag , only the records in the first page are displayed , when i click on the next page it returns an empty result . Ive tried changing the no. of records in the page however only the ones in the first page are displayed and not the rest. Any clues as to where I could be going wrong?
Thanks for replying.

well that should be handled by display tag ( pagination, sorting etc. ), so give the entire list to the tag at one go and it will do all the pagination on its own. If you dont want the tag to do it then it also allows you to use your customized comparators / decorators etc... have a look at the library reference page at sourceforge for further details on those topics.

[Vic Hood]

Well robin , if it were only the problem of pagination then the submit action, that was working would still work? . Why isnt that working then?

[Vic Hood]

Vic Hood wrote:Well robin , if it were only the problem of pagination then the submit action, that was working would still work? . Why isnt that working then?

I meant that 'was' working..Sorry for the typo