Category Archives: ADF Faces

Tuning for ADF


MaxFetchSize

MaxFetchSize is the maximum number of rows fetched from the database for the current view object. Setting -1 will retrieve unlimited number of rows or the entire rows returned from a query. Setting 0 will cause no query execution and no rows will be returned. Check in the VO for this property.

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FetchSize

This is the number of rows that is returned on a single database round trip. This setting will determine how many rows will be returned for a particular view object at run-time on a single query. Set the size In batches of n+1. check in VO, AM instance, table component for this property.

2

FetchMode

This is the mode that controls how the rows are retrieved in a JDBC resultset. Some of the modes allowed for the FETCH_ALL, FETCH_AS_NEEDED. Number of rows retrieved is based on the RangeSize of the VO.

FETCH_ALL – will fetch all the rows at a time. This causes all rows to be retrieved from a JDBC result set immediately, and then closes the result set.

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FETCH_AS_NEEDED – will fetch number of rows defined by the RangeSize first and is again fetched upon request. A fetch mode that causes rows to be retrieved from a JDBC result set as the user navigates through the row set. The result set is closed when the user reaches the end of the row. The executeQuery() will fetch this much only.

4

RangeSize

Number or rows to be displayed in the Iterator collection. Table rows maps to this. By default is 25. Maps from View Object to the UI Collection. Check in VO, Page definition file for this property.

5

ListRangeSize

ListRangeSize is the setting for the List of values that is added to the attribute in the View object which will be set to less value to reduce large number of rows getting returned unnecessarily. Setting -1 will retrieve all the rows. Check in the VO for this property.

6RowCountThreshold

Specify a value to determine if a result set returns the number of rows you specify as a value. If you set RowCountThreshold to 0, the Iterator returns the estimated row count in the result set by executing the count query. If you set RowCountThreshold to less than 0, the Iterator does not execute the count query. If RowCountThreshold is set to -1 then it will load the table faster and will not execute the SELECT COUNT query for the number of data retrieved. Check in page definition file.

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AccessMode

This defines how the row is accessed in a view object. The modes are

SCROLLABLE – Rows are cached in a collection. This is the most flexible mode for accessing rows and working with a RowSet. Ideal for less number of rows. For large numbers use RANGE_PAGING or RANGE_PAGING_INCREMENTAL.

FORWARD_ONLY– Sequential Access to rows in a collection. The Iterator on this RowSet will not allow scrolling back

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RANGE_PAGING – The paging is done based on the RangeSize defined. If the rows which are requested are not in the range then the rows are fetched from the database using the ROWNUM query. it only keeps the current range (or “page”) of rows in memory in the view row cache at a time

RANGE_PAGING_AUTO_POST – The rowset will post any changes in the transaction for rows out of the current range.

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RANGE_PAGING_INCR – the UI incrementally displays the result set from the memory cache and thus supports scrolling within a single database query. the UI incrementally displays the result set from the memory cache and thus supports scrolling within a single database query. The number of rows that the end user can scroll though in a single query is determined by the range size and a range paging cache factor that you set. For example, suppose that you set the range size to 4 and the cache factor to 5. Then, the maximum number of rows to cache in memory will be 4*5 = 20

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Query Optimizer

These are hints added to the query to help retrieve the record efficiently. This will influence the execution plan of the query.  Check in the VO.

ALL_ROWS – Fetch all the rows as soon as possible.

FIRST_ROWS – fetch the first rows as quickly as possible

Row Limit

This is updated in the adf-config.xml file. The value of -1 will fetch all the rows for the VO in the application. You can limit the row limit fetched by the VO in an application using this option.

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AutoHeightRows

The number of rows used to size the component height. The default value is -1 (no auto-sizing for any number of rows). The height of the component can grow to a maximum of autoHeightRows after which a scrollbar is displayed. A value of 0 can be used to default the autoHeightRows to the current fetchSize. autoHeightRows value cannot be larger than fetchSize attribute. Check in the table component.

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How to in Jdeveloper ADF – increase the inputcomboboxlistofvalues dialog width


Problem:

To increase the width of the af:inputcomboboxlistofvalues dialog box.

Solution:

Recently I have been challenged to increase the width of the af:inputcomboboxlistofvalues dialog box. using contentStyle or inlinestyle will increase the width of the component and the dialog box will remain the same. So i thought of playing with the CSS file and could possibly achieve the width with the following hack.


<af:resource type=”css”>
.adf_dialog_main{
   min-width: 500px;
}
</af:resource>

How To in Jdeveloper ADF – To call a VO from another VO or from AM method


Scenario:
How to set an Attribute value from one VO into another VO?

Solution: 

//in you Application module Impl file have the follwing code written inside the method which will set the value for another vo
//lets say UploadView is the View object that you would want to set the value
ViewObject vo = findViewObject("tUploadView");
//if its not in Application Module, you will have to get the VO instance either from iterator if you are using this code in the bean
//get the rowset of UploadView
RowSet rs = vo.getRowSet();
//iterate through
while(rs.hasNext()){
//get the row
Row r = rs.next();
//set the value
r.setAttribute("ValueItem", value); //ValueItem is the Attribute that you want to set
}
}

Jdeveloper 11.1.2.3 is out with ADF Essentials


Jdeveloper 11.1.2.3 is out with ADF Essentials – ADF Free to develop and Deploy.. 🙂

http://www.oracle.com/technetwork/developer-tools/jdev/documentation/index.html

How to in Jdeveloper ADF–Single row table selection


Scenario:

How to enable single row table selection?

Solution:

This seems an obvious question but newbie’s miss to understand this and will find difficulties in fixing this.

So what exactly we do to make the selection happen and confirm that it points to the current row of the af:table.

first, make sure that you have the following entries added to the af:table component of your page

selectedRowKeys="{bindings.Customers.collectionModel.selectedRow}"
selectionListener="#{bindings.Customers.collectionModel.makeCurrent}"
rowSelection="single"

Note: Customers is the tree binding for the table in the page definition file.

So what these entries do?

selectedRowKeys – the state of the selection is stored in this property. This property identifies the current selected row in the collectionModel of the table.

selectionListener – this is a listener that corresponds to the selection of the row. we bind it to the makeCurrent method of the table bindings collectionModel

rowSelection – we make it single row selection.

How To in Jdeveloper ADF Tutorials – Add Date based on another Date


Scenario:

How to calculate the datefield by considering another datefield that’s entered in by the user.
If you have entered a datefield “Today” as 12/04/2012
Now the requirement is to calculate another datefield’s date as 12/04/2012 + 30 days?

Solution:

  • Have two fields in the page. inputDate1 and inputDate2 bounded to the value in the bean as date1 and date2.
  • set inputDate1 autosubmit=true, and inputDate2 partialTrigger is set to the id of the inputDate1

<af:inputDate label="Date 1" id="id1" value="#{bean.date1}" autoSubmit="true"/>
<af:inputDate label="Date 2" id="id2" value="#{bean.date2}" partialTriggers="id1"/>

in the bean for the date fields. have getter and setter

in the getter of the date2 field have the following code


private Date date1;
private Date date2;

public void setDate1(Date date1) {
this.date1 = date1;
}

public Date getDate1() {
return date1;
}

public void setDate2(Date date2) {
this.date2 = date2;
}

public Date getDate2() {
if(date1 != null){
Calendar cal =Calendar.getInstance();
cal.setTime(date1);
cal.add(Calendar.DATE, 30);
date2 = cal.getTime();
}
return date2;
}

The source code is downloaded from here, for Jdeveloper 11.1.2.2.0

How To in Jdeveloper ADF Tutorials – creates new row in af:panelist


Scenario:

How to make a panellist that reads data from a database and according to the number of records in the database creates new row in the panellist?

Solution:


<af:iterator id="i3" value="#{emp.collectionModel}" var="row"> //emp.collectionModel is your collection
          <af:panelList id="pl1">
            <af:outputText value="#{row.empName}" id="ot3"/> // empName is the attribute to show
          </af:panelList>
        </af:iterator>