View Link on two programmatic view objects

Question

Hello,
I use Build JDEVADF_11.1.1.1.0_GENERIC_090615.0017.5407
I have two programmatic View Objects with data from other sources (an ArrayList in my example).
Now I would like to create a View Link on it. How can I do this?
I'm quite new on Java and ADF...
I know it is possible because I already found Steve's example 132 here [http://blogs.oracle.com/smuenchadf/examples/|http://blogs.oracle.com/smuenchadf/examples/]
But could somebody create a simple example based on my example classes below (which is understandable for a newbie like me ;-) ?
Has been asked already here, but I did not found a solution as yet.
Error with view link and ADF table Tree
This is my example code for the view objects:
Employee.java:
private Number empno;
private String ename;
private Number dept;
with getters and setters...
Department.java
private Number deptno;
private String dname;
with getters and setters...
public class StaticDataDepartmentsImpl extends ViewObjectImpl {
int rows = -1;
private List<Department> departments = new ArrayList<Department>();
protected void executeQueryForCollection(Object rowset, Object[] params,
int noUserParams) {
// Initialize our fetch position for the query collection
setFetchPos(rowset, 0);
super.executeQueryForCollection(rowset, params, noUserParams);
// Help the hasNext() method know if there are more rows to fetch or not
protected boolean hasNextForCollection(Object rowset) {
return getFetchPos(rowset) < rows;
// Create and populate the "next" row in the rowset when needed
protected ViewRowImpl createRowFromResultSet(Object rowset,ResultSet rs) {
ViewRowImpl r = createNewRowForCollection(rowset);
int pos = getFetchPos(rowset);
populateAttributeForRow(r, 0, departments.get(pos).getDeptno());
populateAttributeForRow(r, 1, departments.get(pos).getDname());
setFetchPos(rowset, pos + 1);
return r;
// When created, initialize static data and remove trace of any SQL query
protected void create() {
super.create();
// Setup string arrays of codes and values from VO custom properties
initializeStaticData();
rows = (departments != null) ? departments.size() : 0;
// Wipe out all traces of a query for this VO
getViewDef().setQuery(null);
getViewDef().setSelectClause(null);
setQuery(null);
// Return the estimatedRowCount of the collection
public long getQueryHitCount(ViewRowSetImpl viewRowSet) {
return rows;
// Subclasses override this to initialize their static data
protected void initializeStaticData() {
Department d1 = new Department();
d1.setDeptno(new Number(10));
d1.setDname("IT");
Department d2 = new Department();
d2.setDeptno(new Number(20));
d2.setDname("HR");
departments.add(d1);
departments.add(d2);
// Store the current fetch position in the user data context
private void setFetchPos(Object rowset, int pos) {
if (pos == rows) {
setFetchCompleteForCollection(rowset, true);
setUserDataForCollection(rowset, new Integer(pos));
// Get the current fetch position from the user data context
private int getFetchPos(Object rowset) {
return ((Integer)getUserDataForCollection(rowset)).intValue();
public class StaticDataEmployeesImpl extends ViewObjectImpl {
int rows = -1;
private List<Employee> employees = new ArrayList<Employee>();
protected void executeQueryForCollection(Object rowset, Object[] params,
int noUserParams) {
// Initialize our fetch position for the query collection
setFetchPos(rowset, 0);
System.out.println("in executeQueryForCollection");
super.executeQueryForCollection(rowset, params, noUserParams);
// Help the hasNext() method know if there are more rows to fetch or not
protected boolean hasNextForCollection(Object rowset) {
System.out.println("in hasNextForCollection. Rows:" + rows);
return getFetchPos(rowset) < rows;
// Create and populate the "next" row in the rowset when needed
protected ViewRowImpl createRowFromResultSet(Object rowset,ResultSet rs) {
ViewRowImpl r = createNewRowForCollection(rowset);
int pos = getFetchPos(rowset);
System.out.println("in createRowFromResultSet. Pos=" + pos);
populateAttributeForRow(r, 0, employees.get(pos).getEmpno());
populateAttributeForRow(r, 1, employees.get(pos).getEname());
populateAttributeForRow(r, 2, employees.get(pos).getDept());
setFetchPos(rowset, pos + 1);
return r;
// When created, initialize static data and remove trace of any SQL query
protected void create() {
super.create();
// Setup string arrays of codes and values from VO custom properties
initializeStaticData();
rows = (employees != null) ? employees.size() : 0;
System.out.println("in create(). Rows=" + rows);
// Wipe out all traces of a query for this VO
getViewDef().setQuery(null);
getViewDef().setSelectClause(null);
setQuery(null);
// Return the estimatedRowCount of the collection
public long getQueryHitCount(ViewRowSetImpl viewRowSet) {
return rows;
// Subclasses override this to initialize their static data
protected void initializeStaticData() {
Employee e1 = new Employee();
e1.setEmpno(new Number(2333));
e1.setEname("Emp1");
e1.setDept(new Number(10));
Employee e2 = new Employee();
e2.setEmpno(new Number(1199));
e2.setEname("Emp2");
e2.setDept(new Number(20));
Employee e3 = new Employee();
e3.setEmpno(new Number(3433));
e3.setEname("Emp3");
e3.setDept(new Number(10));
Employee e4 = new Employee();
e4.setEmpno(new Number(5599));
e4.setEname("Emp4");
e4.setDept(new Number(20));
Employee e5 = new Employee();
e5.setEmpno(new Number(5676));
e5.setEname("Emp5");
e5.setDept(new Number(10));
Employee e6 = new Employee();
e6.setEmpno(new Number(7867));
e6.setEname("Emp6");
e6.setDept(new Number(20));
employees.add(e1);
employees.add(e2);
employees.add(e3);
employees.add(e4);
employees.add(e5);
employees.add(e6);
// Store the current fetch position in the user data context
private void setFetchPos(Object rowset, int pos) {
if (pos == rows) {
setFetchCompleteForCollection(rowset, true);
setUserDataForCollection(rowset, new Integer(pos));
// Get the current fetch position from the user data context
private int getFetchPos(Object rowset) {
return ((Integer)getUserDataForCollection(rowset)).intValue();
Who can help?
Thnx in advance!
Rolf

Answer 1

Rolf,
I guess when we try to do it for you, we end up with almost the sample code provided by Steve Muench.
So there from my point of view it doesn't make sense to do it all over.
Take some time and study the sample code, run it without changes and after that try some changes which suits your use case better.
If you don't understand what's going on in the sample post the question here and we try to help you.
Timo