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Tuesday 1 December 2015

Some useful Linux commands for Developers

1. find the files modified before a certain time
find /path/to/folder/ -mmin +60
2. find the modified after a certain time
find  /path/to/folder/ -mmin -60

Wednesday 14 October 2015

Some sql errors and resolutions

1. SQL Error: ORA-00932: inconsistent datatypes: expected DATE got NUMBER
Put the input date as DATE '2016-09-30'

2.  <JDBC> <BEA-001129> <Received exception while creating connection for pool "SOADataSource": ORA-28000: the account is locked

and change the password in the datasource added in console

Friday 15 May 2015

Set Initial focus on any ADF UI component

Often developers requires focus on a particular UI component on page load. ADF provides out-of-the-box feature for this problem. All you need is the exact component id of that element.
In this example I will show you how to move cursor to the input box used as a username input. This component was inside a bounded-taskflow exposed in a jspx region.
First the jspx code .

 <af:document id="d1" title="#{sessionScope.pageTitle}" 
partialTriggers="r1" initialFocusId="r1:0:sf1:it1">

This is our login module and now will try to find out its id generated on the webpage by developer tool.
We can now see the actual id of the UI component exposed in browser. It is the same ID we need to put in 

Thursday 14 May 2015

Pitfalls in System.out.print or SOPs

While developing any kind of application we want that application to be as fast as we can. But it is not an easy task to achieve. Making a fast application is easy if the application is not complex. With complexity applications tends to slow down and one of the major reason is - System.out.print() of java.

Some of you may know this fact or some of you not. To understand how costly is this SOP . Let's try to build a simple method to test the speed.

    public static void main(String[] s) throws FileNotFoundException,
                                               IOException {
        String count = "";
        long total=0;
        for (int j = 0; j < 20; j++) {
            long temp=calculateCostofSOP();
            count = count + String.valueOf(temp) + " ";

This loop iterator 20 times to have a clear picture of COST of SOP. Let's now have our implementation of calculateCostofSOP

    public static long calculateCostofSOP() throws FileNotFoundException, IOException {
        FileReader fr =
            new FileReader("C:\\gre");
        PrintWriter pw=new PrintWriter("C:\\grew");
        BufferedReader bfr = new BufferedReader(fr);

        String line = "";
        StringBuilder sb = new StringBuilder();
        long sv = System.currentTimeMillis();
        while ((line = bfr.readLine()) != null) {
            line = line.replace("\t", "=");
            sb.append(line + "\n");
            System.out.println(line);   //comment this line while we use file out
           // pw.write(line + "\n");   //comment this line while we use console out
        FileWriter f =
            new FileWriter("C:\\gre");
        BufferedWriter buffW = new BufferedWriter(f);
        return (System.currentTimeMillis() - sv);
Now look at the output we received. It took whopping 109028 milliseconds. The file "gre" was not too long. It contains data from here https://quizlet.com/47571/export.
But when I commented the SOP line and save data to the file the following output was arrived.

pw.write(line + "\n"); 
Now, it took only 1062 milliseconds.
Try it by yourself and see the results. By the above experiment we reach to following conclusion.

  • Try to avoid SOPs as much as you can
  • Never try to put SOPs inside any loop.
  • In prod applications use ADFLogger or log4j for the better performance.
  • If possible concat the String inside the loop and SOP it outside the loop.In my case it took-45216 ms

Tuesday 27 January 2015

Using google / custom fonts in the ADF application

In ADF use can use any google font as you used to use default fonts provided by ADF or Webcenter.
Here are the steps.

  1. Register the css file in the page through the af:resource tag
<af:resource type="css" source="http://fonts.googleapis.com/css?family=Lobster"/>

     2. Make an entry in the application's css file.

.inText {
    font-family: 'Lobster', cursive;
    font-size: medium;

   3. Put the above styleclass in the component
<af:outputText styleClass="inText " value="Text with google font"

Precaution while using javascript in a page fragment or in ADF region

Don't include javascript in the page Fragment just after the jsp:root tag . It will cause undesired effects if this page is navigated from somewhere else.
This will be a wrong approach for a jsff page
<jsp:root xmlns:jsp="http://java.sun.com/JSP/Page" version="2.1"
  <af:resource type="javascript" source="/js/custom.js"/>

The right approach is to include this resource component inside a  container component . Like this
  <af:resource type="javascript" source="/js/custom.js"/>

Tuesday 13 January 2015

ADF Performance Tuning part-1 - Production tuning

  1. animation-enabled=false in trinidad-config.xml file
  2. in web.xml file do the following changes if not done already
    1. oracle.adf.view.rich.automation.ENABLE=false
    2. oracle.adf.view.rich.ASSERT_ENABLED=false
    3. org.apache.myfaces.trinidad.CHECK_FILE_MODIFICATION=false
    4.  org.apache.myfaces.trinidad.COMPRESS_VIEW_STATES=true
    5. org.apache.myfaces.trinidad.DEBUG_JAVASCRIPT=false
    6. org.apache.myfaces.trinidad.DISABLE_CONTENT_COMPRESSION=false
    7. oracle.adf.view.rich.libraryPartitioning.DISABLED=false 
    8. oracle.adf.view.rich.LOGGER_LEVEL=false
    9. javax.faces.STATE_SAVING_METHOD=client 
    10. oracle.adf.view.rich.versionString.HIDDEN=true

  3.  Use the ADFLogger
  4. Don't use System.out.* or System.err.* - These have major impact on performance
  5. Remove commented out code
  6. Do not import view or controller classes
  7. Close callableStatement, preparedStatements and RowSetIterators
  8. Use application module JDBC data source only not  JDBC URLs.
  9. Run with Enable Application Module pooling on for production .
  10. Define at least one entity object key attribute per entity object.
  11.  Ensure entity object UI Hints and messages are internationalized
  12. Avoid read only view objects as far as possible
  13. Use view criteria over editing view object where clauses
  14. Never use view object select *
  15. Limit custom code in bean accessors -ie. in getters and setters
  16. Use beans only defined in the task flow for reuse 
  17. Avoid applicationScope and sessionScope variables
  18. Define applicationScope and sessionScope beans in adfc-config.xml
  19. Only create backing beans when actually needed, do not bind unnecessary component references into backing beans.
  20. Avoid long component ID lengths.
  21. Avoid unnecessary use of clientComponent=true
  22. Use rendered=false over visible=false wherever possible.
  23. Never rely on UI side validation.
  24. Avoid inline page/fragment JavaScript and CSS
  25. Manual tests for UIs should include stretch / shrink behavior.
  26. Manual tests for UIs should include changing font size[Zoom-in and Zoom-out testing]
  27. url.rewriting.enabled should be false in weblogic.xml
  28. Make sure jbo.debugoutput  is disabled for production
  29. Make HA available. Add this entry in adf-config.xml file
  <adf-controller-config xmlns="http://xmlns.oracle.com/adf/controller/config">

Monday 5 January 2015

Useful methods in Oracle ADF part-2

//1. Method to call a flow in taskFlow programatically 

 public static void gotoFlow(String flowName) {
        FacesContext context = FacesContext.getCurrentInstance();
        Application app = context.getApplication();
        NavigationHandler handler = app.getNavigationHandler();
        handler.handleNavigation(context, null, flowName);
//2. Util method to show error and Success Msg
 public static void showMsg(String msgBody, String msgSeverity) {
        FacesMessage fm = new FacesMessage(msgBody);
        if (msgSeverity.equals("info")) {
        } else if (msgSeverity.equals("warn")) {
        } else if (msgSeverity.equals("error")) {
        } else {
        FacesContext fctx = FacesContext.getCurrentInstance();
        fctx.addMessage(null, fm);
//3. Get Cookie value in ADF
        public static String getCookieValue(String cookieName) {
        FacesContext fctx = FacesContext.getCurrentInstance();
        ExternalContext ectx = fctx.getExternalContext();
        Map vRequestCookieMap = ectx.getRequestCookieMap();
        Cookie cookie = (Cookie)vRequestCookieMap.get(cookieName);
        if (cookie != null) {
            return cookie.getValue();
        return null;
//4. Load a jsp or jspx page (redirect to a page)
  public static String loadPage(String pageName) {
        FacesContext vFacesContext = FacesContext.getCurrentInstance();
        ExternalContext vExternalContext = vFacesContext.getExternalContext();
        ControllerContext controllerCtx = null;
        controllerCtx = ControllerContext.getInstance();
        String activityURL = controllerCtx.getGlobalViewActivityURL(pageName);
        try {
        } catch (IOException e) {

        return null;
//5. Initializing the ADFLogger

private static ADFLogger _logger = 
//6. Clear the ADF table filter
    public static void removeFilter(RichTable tableBind,String processQueryName) {
        FilterableQueryDescriptor queryDescriptor =
        if (queryDescriptor != null &&
            queryDescriptor.getFilterCriteria() != null) {
//processQueryName can found in queryListner of table eg:- #{bindings.Employee1Query.processQuery}
                                              Object.class, QueryEvent.class,
                                              new QueryEvent(tableBind,
// 7.Implementing like type filter in ADF table filter
public static void likeFilter(RichTable tableBind,String processQueryName) {
        FilterableQueryDescriptor queryDescriptor =
        if (queryDescriptor != null &&
            queryDescriptor.getFilterCriteria() != null) {
            Map m=queryDescriptor.getFilterCriteria();
            Set keys = m.keySet();
           Map modified=new HashMap();
            for (Iterator i = keys.iterator(); i.hasNext();) {
                  String key = (String) i.next();
                  String value = (String) m.get(key);
                if(value!=null && !value.equals("")){
                  System.out.println(key + " = " + value);
                                              Object.class, QueryEvent.class,
                                              new QueryEvent(tableBind,
                                              Object.class, QueryEvent.class,
                                              new QueryEvent(tableBind,
// 8. Launching / Invoking a PopUp from Bean. [popupBind is binding of popup inside the bean]
RichPopup.PopupHints hints = new RichPopup.PopupHints();