Oracle ADF | Techartifact

August 30, 2013

Set value in attribute in binding in Oracle ADF

Requirement – how to set value of attribute value in binding…

Solutions – you can use this expression –

JsfUtils.setExpressionValue("#{ManagedBean.empName}", "Vinay");

You have to add this method in JsfUtils class.

Note to call the getters and setters via your EL expression, you don’t include the get/set prefix.

 public static void setExpressionValue(String expression, Object newValue) {
    FacesContext facesContext = getFacesContext();
    Application app = facesContext.getApplication();
    ExpressionFactory elFactory = app.getExpressionFactory();
    ELContext elContext = facesContext.getELContext();
    ValueExpression valueExp = elFactory.createValueExpression(elContext, expression, Object.class);

    //Check that the input newValue can be cast to the property type
    //expected by the managed bean.
    //If the managed Bean expects a primitive we rely on Auto-Unboxing
    //I could do a more comprehensive check and conversion from the object
    //to the equivilent primitive but life is too short
    Class bindClass = valueExp.getType(elContext);
    if (bindClass.isPrimitive() || bindClass.isInstance(newValue)) {
      valueExp.setValue(elContext, newValue);
    }
  }

Happy coding in Techartifact with Vinay…

August 18, 2013August 18, 2013

Generate Excel file in Oracle ADF using Apache POI

Requirement:Generate excel file using open source “Apache POI” to generate excel spreadsheets from my ADF application.

Advantage of using POI over default export collectionListener of ADF –

1. Using Apache POI, you can not only export excels but also can read excel files (.xls or .xlsx) from local machines and upload them to ADF applications
2. User has more control on the excel output file (than using “Export Collection Action Listener”)
for e.g. you can put data formatting for your currency/date column, freeze panes, apply filters etc.
3. Size of generated excel is less than from export CollectionListener.

Solution-

You need to download the apache POI jar from poi.apache.org

–>> poi-3.7-20101029.jar
You need to add this jar in project libraries and classpath of project.

Creating a sample project (using Department and Employee tables) and attaching libararies.

I would like to keep it simple as we don’t want to focus on any steps other than excel here, here are quick steps to create a sample application

1. create view object using query on locations table.
2. Expose the VO to applicationModule.then drag drop VO from data control to page as table
3. Place a command button anywhere on the page and label it as “ExporToExcel”
4. Drop a “” component on this button.
Put property of af:fileDownloadActionListener as follows
-> contentType: application/vnd.openxmlformats-officedocument.spreadsheetml.sheet or you can use “application/octet-stream” .
-> ExcelFromPoi.xls
-> Method: #{PoiBean.generateExcel} //custom method call to export data

Now writing a custom method in managed bean to export locations shown in the screen.
I am writing an generateExcel() method.

In short, follow the steps-
create a Workbook object.create a Sheet object.Get object of bindings .After that we will get page iterator and from that iterator we will get all rows in that range. Start creating row first and then cells. After completion of sheet , we will writing outputStream on the workBook.

Following is code of managed bean –

package vinay.view;

import com.sun.jmx.snmp.Timestamp;

import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.OutputStream;

import java.util.HashMap;
import java.util.Map;

import javax.faces.context.FacesContext;
import org.apache.poi.hssf.usermodel.HSSFCell;
import org.apache.poi.hssf.usermodel.HSSFCellStyle;
import org.apache.poi.hssf.usermodel.HSSFDataFormat;
import org.apache.poi.hssf.usermodel.HSSFRow;
import org.apache.poi.hssf.usermodel.HSSFSheet;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.hssf.util.HSSFColor;
import oracle.adf.model.BindingContainer;
import oracle.adf.model.BindingContext;
import oracle.adf.model.binding.DCBindingContainer;

import oracle.adf.model.binding.DCIteratorBinding;



public class PoiBean {
    public PoiBean() {
    }


        public static BindingContainer getBindingContainer() {
            //return (BindingContainer)JSFUtils.resolveExpression("#{bindings}");
            return (BindingContainer)BindingContext.getCurrent().getCurrentBindingsEntry();
        }

        public static DCBindingContainer getDCBindingContainer() {
            return (DCBindingContainer)getBindingContainer();
        }
      
      public void generateExcel(FacesContext facesContext, OutputStream outputStream) throws IOException {
          try {
         
                            
                                HSSFWorkbook workbook = new HSSFWorkbook();
                                    HSSFSheet worksheet = workbook.createSheet("POI Worksheet");
              
                                DCBindingContainer bindings = (DCBindingContainer)BindingContext.getCurrent().getCurrentBindingsEntry();
                                DCIteratorBinding dcIteratorBindings = bindings.findIteratorBinding("ViewObj1Iterator");
                                HSSFRow  excelrow = null;
              
                                        // Get all the rows of a iterator
                                        oracle.jbo.Row[] rows = dcIteratorBindings.getAllRowsInRange();
                                    int i = 0;
                             

                                            for (oracle.jbo.Row row : rows) {

                                                //print header on first row in excel
                                                if (i == 0) {
                                                    excelrow = (HSSFRow)worksheet.createRow((short)i);
                                                    short j = 0;
                                                    for (String colName : row.getAttributeNames()) {
                                                      
                                                            HSSFCell cellA1 = excelrow.createCell((short) j);
                                                            cellA1.setCellValue(colName);
                                                            j++;
                                                        
                                                    }
                                                }

                                                //print data from second row in excel
                                                ++i;
                                                short j = 0;
                                                excelrow = worksheet.createRow((short)i);
                                                for (String colName : row.getAttributeNames()) {
                                                    System.out.println("hello "+row.getAttribute(colName));
                                                    System.out.println("hello "+colName);
                                                        HSSFCell  cell = excelrow.createCell(j);
                                                    if (colName.equalsIgnoreCase("DepartmentId")) {

                                                       
                                                        cell.setCellValue(row.getAttribute(colName).toString());
                                                        System.out.println("colName "+colName+"row.getAttribute(colName).toString()"+row.getAttribute(colName).toString());
                                                    }
                                                        //logic for cell formatting
                                                        if (colName.equalsIgnoreCase("DepartmenName")) {
                                                            cell.setCellValue(row.getAttribute(colName).toString());
                                                            
                                                        }
                                                        //make it double if you want and convert accordingly
                                                        else if (colName.equalsIgnoreCase("LocationId")){
                                                            cell.setCellValue(row.getAttribute(colName).toString());
                                                        }
                                                        else if (colName.equalsIgnoreCase("ManagerId")){
                                                            if(null!=row.getAttribute(colName)){
                                                            cell.setCellValue(row.getAttribute(colName).toString());
                                                            }
                                                        } else
                                                         cell.setCellValue(row.getAttribute(colName).toString());

                                                        j++;
                                                      
                                                    }
                                                
                                                   worksheet.createFreezePane(0, 1, 0, 1);
                                               } 
              workbook.write(outputStream);
              outputStream.flush();
              
          }
                                            catch (Exception e) {
                                          e.printStackTrace();
                                            }
                                        
      }
      }

You can freeze the header like this —

worksheet.createFreezePane(0, 1, 0, 1);

Resize the column automatically –

            sheet.autoSizeColumn(0);
            sheet.autoSizeColumn(1);
            sheet.autoSizeColumn(2);
            sheet.autoSizeColumn(3);

And finally you can get the generated excel report like below

you can download the sample application from below, I have also illustrat how you can generate excel using export collectionListner in sample application.Button label as exportCollectionActionListener –

exportToExcel

Happy coding with Vinay kumar in Techartifact

August 9, 2013August 9, 2013

Dynamic Creation of cascading Lov in oracle ADF or model driven Lov in Oracle ADF.

Requirement – I am working on tricky requirement where i have two child component and one child LOV.How to do that?

Solution- Well if you have working knowledge of cascading LOV in then we pass bind parameter of parent LOV attribute in child LOV View Accessor(VA) . But in this scenario , we have two master LOV. then we will be doing by passing through managed bean, using Application module session .

What i have done.I have used HR schema .

I have 3 view object. one as country table of HR schema.One View object for location table.One view which have all transient attribute and consider to be main view object.

As i found this approach in Jobinesh’s blog- i write a custom method in applicationModuleImpl.java as below –

    public void setLocationIDSessionData(String locId){
          System.out.println("hello 232323&&&"+locId);
        this.getSession().getUserData().put("LocationId", locId);
        
      }

I have getUserData method of applicationModule interface which returns a java.util.Hashtable which may be used to store user specific context that is related to this application session.

Read all other method related to this
http://docs.oracle.com/cd/E12839_01/apirefs.1111/e10653/oracle/jbo/ApplicationModuleHandle.html

Ok, coming back to this requirement – I used a managed bean in backing bean scope where i executed the binding of applicationModuleImpl custom method as below –

    public void executec(String valueChangeEvent) {
    BindingContext bctx = BindingContext.getCurrent();
           BindingContainer bindings = bctx.getCurrentBindingsEntry();
           OperationBinding op =
               (OperationBinding)bindings.getOperationBinding("setLocationIDSessionData");
           op.getParamsMap().put("locId",valueChangeEvent);
           op.execute();
    }

Here we are passing the value of both LOV to locationId to custom applicationModuleImpl method.In both parent LOV , i create valuechangeEvent method , which get the current selected countryId and pass to custom applicationModuleImpl method. that is below –

    public void VC(ValueChangeEvent valueChangeEvent) {
      System.out.println("hello &&&"+valueChangeEvent.getNewValue());
      
       
        executec(valueChangeEvent.getNewValue().toString());
    }

    public void vc2(ValueChangeEvent valueChangeEvent) {
        System.out.println("hello &&&34343"+valueChangeEvent.getNewValue());
        executec(valueChangeEvent.getNewValue().toString());
    }

Now we have final task, we have to set the value of child lov bind parameter in child View Accessor as adf.userSession.userData.LocationId –

That’s it.now we will run the jspx , which have all 3 lov.2 parent and one child LOV.
for displaying LOV , we need to click on create button.after click you can see all 3 LOVs.