Iterate query result - put specific rows in a collection and do output

Question

JDeveloper 11.1.1.3.0
Oracle Lite: 10.2.0.1.0
Browser: IE 7
Hi,
please help me in working on following requirement:
1. Iterate the View Object Query Result
2. Do some calculation on the Rows, lets say:
Concatination of column1 and column2 and place it in a non database Attribute "column3"
3. How to handle/place the non database attribute?
4. Fetch specific rows from the query result; there should be a comparison, like checking master and detail hierachy struktur:
Take Column1_ID (Master) check in columns2_ID (Detail), when found detail take this Row and place it in a buffer (Maybe ArrayList, or something like that)
5. Show the Chace(ArrayList) to user, in a form of View Object, with standard functions like sorting and filtering
Till now my process of solving the above requiremnts are:
To Point 1:
Created a service method in Application Implementation Class
   public void iterateEmp(){
     EmployeesVOImpl vo = getEmployeesVO1();
     while (vo.hasNext()){
      EmployeesVORowImpl row = (EmployeesVORowImpl)vo.next();
      System.out.println(row.getEmployeeId() + " | " + row.getFirstName() + " | " + row.getLastName() + " | " +  row.getEmail());   
      //row.setCalcCol(row.getFirstName() + "," + row.getLastName());
     }To point 2:
Added an attribute to the View Object, with updateable and Queryable options. Place it on the JSPX Page.
With setter method, filled with values, for example (non Database Attributes Name is CalcCol):
Name:
//see above code
row.setCalcCol(row.getFirstName() + "," + row.getLastName());When doing so, on initial Call the values will be representated, but when sorting o filtering will be done, the values then will be erased.
3. Added an Attribute in View Object "Attributes Panel".
Here the XML Code of the View Object:
<?xml version="1.0" encoding="windows-1252" ?>
<!DOCTYPE ViewObject SYSTEM "jbo_03_01.dtd">
<!---->
<ViewObject
  xmlns="http://xmlns.oracle.com/bc4j"
  Name="EmployeesVO"
  Version="11.1.1.56.60"
  BindingStyle="OracleName"
  CustomQuery="true"
  ComponentClass="model.EmployeesVOImpl"
  PageIterMode="Full"
  UseGlueCode="false"
  RowClass="model.EmployeesVORowImpl">
  <DesignTime>
    <Attr Name="_codeGenFlag2" Value="Access|Coll|VarAccess"/>
    <Attr Name="_isExpertMode" Value="true"/>
    <Attr Name="_isCodegen" Value="true"/>
  </DesignTime>
  <SQLQuery>
    <![CDATA[select employee_id, first_name, last_name, email from employees]]>
  </SQLQuery>
  <ViewAttribute
    Name="EmployeeId"
    IsUpdateable="false"
    IsPersistent="false"
    IsNotNull="true"
    PrecisionRule="true"
    Precision="6"
    Scale="0"
    Type="oracle.jbo.domain.Number"
    ColumnType="NUMBER"
    AliasName="EMPLOYEE_ID"
    Expression="EMPLOYEE_ID"
    SQLType="NUMERIC">
    <DesignTime>
      <Attr Name="_DisplaySize" Value="22"/>
    </DesignTime>
  </ViewAttribute>
  <ViewAttribute
    Name="FirstName"
    IsUpdateable="false"
    IsPersistent="false"
    PrecisionRule="true"
    Precision="20"
    Type="java.lang.String"
    ColumnType="VARCHAR2"
    AliasName="FIRST_NAME"
    Expression="FIRST_NAME"
    SQLType="VARCHAR">
    <DesignTime>
      <Attr Name="_DisplaySize" Value="20"/>
    </DesignTime>
  </ViewAttribute>
  <ViewAttribute
    Name="LastName"
    IsUpdateable="false"
    IsPersistent="false"
    IsNotNull="true"
    PrecisionRule="true"
    Precision="25"
    Type="java.lang.String"
    ColumnType="VARCHAR2"
    AliasName="LAST_NAME"
    Expression="LAST_NAME"
    SQLType="VARCHAR">
    <DesignTime>
      <Attr Name="_DisplaySize" Value="25"/>
    </DesignTime>
  </ViewAttribute>
  <ViewAttribute
    Name="Email"
    IsUpdateable="false"
    IsPersistent="false"
    IsNotNull="true"
    PrecisionRule="true"
    Precision="25"
    Type="java.lang.String"
    ColumnType="VARCHAR2"
    AliasName="EMAIL"
    Expression="EMAIL"
    SQLType="VARCHAR">
    <DesignTime>
      <Attr Name="_DisplaySize" Value="25"/>
    </DesignTime>
  </ViewAttribute>
  <ViewAttribute
    Name="CalcCol"
    IsSelected="false"
    IsPersistent="false"
    PrecisionRule="true"
    Type="java.lang.String"
    ColumnType="VARCHAR2"
    AliasName="VIEW_ATTR"
    SQLType="VARCHAR"/>
  <AttrArray Name="KeyAttributes">
    <Item Value="EmployeeId"/>
  </AttrArray>
</ViewObject>To Point 4:
There should be a specific sort order, which i have to code in ADF.
Just to give an overview:
Colum1 and Column2 (nothing to do with the emp table) have relationship. Several hierachies are existing in the Query Result.
For identifying the start point of any of these hierachies, i have to iterate through the Query Result and fetch these start point
and buffer it in an array or something like that.So in the end i have to get the same query Result but with different Sort Order.
How to buffer theses Rows (Array?) and show in a View Object?
Can we use the same view Object for solving that, or should we use another View Object which catches the new Result Set?
To Point 5:
The Result should be, as mentioned above, a View Object including new Result Set, which can provide standard behavior (sort, filter)
I hope the requirement is defined clearly enough, so maybe you can make some suggestions on that.
Thank you for replies.
Edited by: user9198377 on 13.07.2011 02:52

Answer 1

Hi.. You can do this without DB View. Have CalcCol transient attribute in VO. Instead of iterating VO rows and setting CalcCol attr, generate View Row Impl class. Inside getCalcCol(), write your logic. This will be called during each and every request so that transient attr data won't become null during sorting and filtering. If your VO is entity driven, do the same in Entity impl class
Raghu
Edited by: Raguraman on Sep 5, 2011 9:48 AM