Code Coverage in ADF with EMMA

If you have a requirement for doing code coverage in an ADF application you can easily accomplish it using EMMA. The good thing about EMMA is that it supports offline instrumentation which essentially helps in collecting and merging the data from various runs plus in case of offline instrumentation you are not affected by the runtime class loading behavior of the application container. The concept in brief is to have the compiled classes with byte-code instrumentation done by EMMA and then later post you run your use cases you can merge the coverage data with the class metadata and generate the report regarding the code coverage done during testing.
The steps to accomplish it for your ADF app are simple.

1. Just create an ant build file for each of your projects i.e one for your model project and the other for your view project. Also make sure that you select the ojdeploy tasks while doing so for your view controller project.
   
2. Now add the emma ant task for generating the class metadata for each of your projects. The following snippet shows the relevant ant tasks for the ViewController project.

   <property file="build1.properties"/>
       <path id='emma.lib' >
       <pathelement location="${emma.dir}/emma.jar"/>
       <pathelement location="${emma.dir}/emma_ant.jar"/>
     </path>
      <taskdef resource="emma_ant.properties" classpathref="emma.lib"/>
    <target name="init">
       <tstamp/>
       <mkdir dir="${output.dir}"/>
        <mkdir dir="${coverage.dir}"/>
       <mkdir dir="${instrumentation.dir}"/>
     </target>
   <target name="emma" description="turns on EMMA instrumentation/reporting" >
       <!-- EMMA instr class output directory: -->
        <property name="emma.enabled" value="true" />
       <property name="out.instr.dir" value="outinstr" />
       <mkdir dir="${out.instr.dir}" />
   </target>
   <target name="emmabuild" depends="clean,init,compile,emma,copy" description="runs the examples" >
       <emma  enabled="${emma.enabled}"  >
       <instr merge="yes" filter="com.blogspot.*"  destdir="${instrumentation.dir}" instrpath="${output.dir}" mode="copy"/>
    </emma>
    </target>
     <target name="instrumentView" description="Copy instrumented classes to output directory"
             depends="emmabuild">
             
       <patternset id="copy1.patterns">
       <include name="**/*.class"/>
       </patternset>
          <copy todir="${output.dir}">
         <fileset dir="${instrumentation.dir}">
           <patternset refid="copy1.patterns"/>
         </fileset>
         </copy>
     </target>

   
   As can be seen from the above snippet EMMA provides you with filtering capabilities so that you can select the classes that you want to be part of the instrumented build.



3. The following snippet shows the relevant snippet from ojdeploy task
   

   <target name="deploy" description="Deploy JDeveloper profiles"
             depends="instrumentView">
   .........
   ..........
   
    <ora:deploy>
           <ora:parameter name="workspace"
                          value="${oracle.jdeveloper.workspace.path}"/>
          <parameter name="nodatasources" value="true"/>
          <parameter name="forcerewrite" value="true"/> 
           <ora:parameter name="profile"
                          value="${oracle.jdeveloper.deploy.profile.name}"/>
           <ora:parameter name="nocompile" value="true"/>
           <ora:parameter name="outputfile"
                          value="${oracle.jdeveloper.deploy.outputfile}"/>
         </ora:deploy>
   </target>

   
   Notice the nocompile option is set to true because we do not want the ojdeploy build task to overwrite the instrumented classes.



4. Also i have added the following snippet to the copy task so that the page definitions are also included in the ear that is going to be generated
   

   <fileset dir="adfmsrc">
         <patternset refid="copy.patterns"/>
         </fileset>

   
   



5. Now to build the project just run the ant task instrumentModel followed by the deploy task and you will have the ear file with instrumented build. Also you will have class metadata file coverage.em generated for each of your projects (rename either one as coverage1.em)



6. Place only the emma.jar into lib/ext directory of the jre used by your weblogic server.



7. Start the weblogic server, deploy the generated ear file and run through a flow and shutdown the server, you will see in the logs the location of generated coverage file (coverage.ec)



8. Place all the three files in one directory (only for ease of use) and run the following command to generate the html report showing the code coverage done while executing your flow.
   
   
   
   

   java emma report -report html,txt -in "C:/emmareport/coverage.em" -in "C:/emmareport/coverage1.em" -in "C:/emmareport/coverage.ec" -Dreport.html.out.file="C:/emmareport/coverage.html" 

   
   Sample images of the report are shown below.
   
   
   
   

The sample application can be downloaded from here.

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ADF 11gR2 custom facelet component for image/flash preview

I have created a custom faces component for previewing the uploaded images/flash files. It is a facelet component and the implementation is very crude but i hope that the product team can come up with something better. As other frameworks like richfaces/primefaces do have this kind of component. The component does not have any renderer  registered with it. The entire thing is being handled in the component class.

The logic on which this component is based upon is to render markup based upon content type of the file. It then generates a URL to which a servlet is registered to write the data back to the stream. There are a couple of things to note 1) The values are being stored in session so for large files this will be a issue, a better implementation can store the file in temporary location and then retrieve it, The other thing is it only handles images and flash file preview but this can be extended for text,js or pdf preview.

The component class below extends UIXOutput so as to provide partialTrigger attribute for partial update of component tree.

package com.blogspot.ramannanda.components;
import java.io.IOException;
import java.net.MalformedURLException;
import java.net.URI;
import java.net.URISyntaxException;
import java.util.HashMap;
import java.util.Map;
import javax.faces.context.FacesContext;
import javax.faces.context.ResponseWriter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpSession;
import org.apache.myfaces.trinidad.component.UIXOutput;


/**
 * @author Ramandeep Nanda
 */
public class RichPreviewOutput extends UIXOutput{
    public RichPreviewOutput() {
        super();
        this.setRendererType(null);
    }


  @Override
    public void encodeEnd(FacesContext facesContext) throws IOException {
        super.encodeEnd(facesContext);
        String elementType=(String)this.getAttributes().get("elementType");
        byte[] data= (byte []) this.getAttributes().get("data");
        if(elementType!=null){
            if(elementType.contains("image")){
                encodeImage(facesContext);
                }
            else
            if(elementType.contains("application/x-shockwave-flash")){
                encodeFlash(facesContext);
                }
            }
        
    }


    private void encodeImage(FacesContext facesContext) throws IOException {
       ResponseWriter writer=  facesContext.getResponseWriter();
       writer.startElement("img", this);
       String fileName=(String)getAttributes().get("filename");
       String uri= generateResourceUrl(fileName);
       String uriAttr=(String)this.getAttributes().get("uriAttr");
       String contentType=(String)this.getAttributes().get("elementType");
       writer.writeAttribute(uriAttr, uri, uriAttr);
            String style=(String)getAttributes().get("style");
            if(style==null){
            writer.writeAttribute("style","width=100px height=100px","style");
            }
            else{
                writer.writeAttribute("style", style, "style");
                }
       byte [] data=(byte[])getAttributes().get("data");
       Map map=new HashMap();
       map.put("data",data);
       map.put("contenttype",contentType);
       HttpSession session=(HttpSession) facesContext.getCurrentInstance().getExternalContext().getSession(false);
       session.setAttribute(fileName, map);
       writer.endElement("img");

       
        }

    private String generateResourceUrl(String fileName) {
       HttpServletRequest request=(HttpServletRequest)FacesContext.getCurrentInstance().getExternalContext().getRequest();
       String ctxtPath=FacesContext.getCurrentInstance().getExternalContext().getRequestContextPath().toString();
       String resPath=FacesContext.getCurrentInstance().getExternalContext().getInitParameter("ServletPath");
       ctxtPath=request.getRequestURL().toString();
       ctxtPath=ctxtPath.substring(0,ctxtPath.lastIndexOf("/faces"));
       ctxtPath=ctxtPath+resPath+"?fileName="+fileName;
       
       URI uri=null;
       String returnURI=null;
       try {
         uri=new URI(ctxtPath);
        } catch (URISyntaxException e) {
           e.printStackTrace();
        }
        try {
            System.out.println(uri.toString());
            returnURI=uri.toURL().toString();
            
        } catch (MalformedURLException e) {
         System.out.println(returnURI);
         e.printStackTrace();
        }
        return returnURI;
    }


    private void encodeFlash(FacesContext facesContext) throws IOException{
        ResponseWriter writer=  facesContext.getResponseWriter();
        writer.startElement("object", this);
        String fileName=(String)getAttributes().get("filename");
        String uri= generateResourceUrl(fileName);
        String uriAttr=(String)this.getAttributes().get("uriAttr");
        String contentType=(String)this.getAttributes().get("elementType");
        writer.writeAttribute(uriAttr, uri, uriAttr);
        writer.writeAttribute("type",contentType , "elementType");
        String style=(String)getAttributes().get("style");
        if(style==null){
        writer.writeAttribute("style","width=100px height=100px","style");
        }
        else{
            writer.writeAttribute("style", style, "style");
            }
        writer.writeAttribute(uriAttr, uri, uriAttr);
        writer.startElement("param", this);
        writer.writeAttribute("name", "flash", "param name");
        writer.writeAttribute("value",uri, "uri");
        writer.endElement("param");
        writer.startElement("a",this);
        writer.writeAttribute("href","http://www.adobe.com/go/getflash", "href");
        writer.writeText("Get Flash", null);
        writer.endElement("a");
        writer.endElement("object");
        byte [] data=(byte[])getAttributes().get("data");
        Map map=new HashMap();
        map.put("data",data);
        map.put("contenttype",contentType);
        HttpSession session=(HttpSession) facesContext.getCurrentInstance().getExternalContext().getSession(false);
        session.setAttribute(fileName, map);
        
    }
}

The tag attributes and usage is shown below.

<f:view xmlns:f="http://java.sun.com/jsf/core"
        xmlns:h="http://java.sun.com/jsf/html"
        xmlns:preview="com.blogspot.ramannanda.components"
        >
    <document title="untitled1.jsf"
          id="d1"    xmlns="http://xmlns.oracle.com/adf/faces/rich"
            >
        
        <form id="f1" usesUpload="true">
           
     <panelGroupLayout id="pgl1">
   <inputFile value="#{pageFlowScope.TestUploadBacking.file}" label="Upload" id="if1"/>
   <preview:richpreview data="#{pageFlowScope.TestUploadBacking.data.data}"
                       style="width:100px;height:100px"   elementType="#{pageFlowScope.TestUploadBacking.data.elementType}"
                          filename="#{pageFlowScope.TestUploadBacking.data.fileName}"
                         uriAttr="#{pageFlowScope.TestUploadBacking.data.uriAttr}"
                         value="#{pageFlowScope.TestUploadBacking.data.value}"/> 
    <commandButton text="Submit"
                      action="#{pageFlowScope.TestUploadBacking.uploadAction}" id="cb1"/>
  </panelGroupLayout>

        </form>
    </document>
</f:view>

Here data is a POJO class.

The attributes and their meaning for tag richpreview  is explained below
elementtype- The content type of the element. This attribute is required.
uriattr- The uri attribute. This can either be src or data and depends upon whether it is a image file or a flash file, for an image it is src and for flash it is data.This attribute is required.
data- It represents the actual data in a byte array. It is required.
filename- It is used for specifying the name of the file. It is required

Wherever you have to use the tag the registration of the resource servlet will be  required along with a init param as shown below. The ServletPath param has to be same as url pattern.

<context-param>
  <param-name>ServletPath</param-name>
  <param-value>/myservlet</param-value>
  </context-param>

  <servlet>
  <servlet-name>MyResourceServlet</servlet-name>
  <servlet-class>com.blogspot.ramannanda.DynamicResourceServlet</servlet-class>
  </servlet>
  <servlet-mapping>
  <servlet-name>MyResourceServlet</servlet-name>
  <url-pattern>/myservlet</url-pattern>
</servlet-mapping>

The entire source code for the tag library and sample usage project can be downloaded from below links.

Tag library project
Sample usage
Tag library

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taskflowViewable vs userInRole

This is a short post about how one can use ADF security to hide/show links to the taskflows depending upon the user role. We can either use userInRole or taskflowViewable EL expressions on the visible or rendered property of the af:command link. But, choosing one over the other has repercussions on maintainability and also causes replication of security configuration in the source code   The preferred way, i think is to use taskflowViewable expression as it avoids the aforementioned problems. This can be seen by the sample usage of the aforementioned expressions below.
1. taskflowViewable :-

<af:commandLink id="cl1" rendered="#{securityContext.taskflowViewable['/pathtotaskflowdefinition/#taskflow_defn_id']}" >
  <af:setPropertyListener type="action"   from="/pathtotaskflowdefinition/#taskflow_defn_id" to="#{viewScope.NavBacking.taskFlowId}" />
              </af:commandLink>

2. isUserRole:-

<af:commandLink id="cl1" rendered="#{securityContext.userInRole['abcRole','xyzRole']}" >
   <af:setPropertyListener type="action"   from="/pathtotaskflowdefinition/#taskflow_defn_id" to="#{viewScope.NavBacking.taskFlowId}" />
              </af:commandLink>
 

As you can see the first expression is only concerned with implicitly restricting access to the users of the particular taskflow that have not been granted access in jazn-data.xml file whereas, the second expression is doing so explicitly by mentioning two specific application roles hence it is causing replication and maintenance issues.

The second snippet by explicitly specifying which users can access the taskflow is replicating the security configuration made in the jazn-data.xml and also if a need arises to grant or revoke access to the taskflow, code change will be required in the second scenario along with the merging of security policy where as in former case only thing required will be the merging of security policy. Hence you should prefer taskflowViewable over userInRole.

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ADF ViewCriteria performance impact

There is a caveat i wanted to highlight with respect to view criteria that has a performance impact.
if you use a view criteria it is applied after the query block as shown below.
This example is based on the scott schema.

select * from (select empno from emp)QRSLT where empno=2;

Now the query execution plan will be the same to the output of the following query where you filter the records inside rather than using a viewcriteria.

select empno from emp where empno=:bvar;

The plan is shown below :-

PLAN_TABLE_OUTPUT
--------------------------------------------------------------------------------
Plan hash value: 56244932

----------------------------------------------------------------------------
| Id  | Operation         | Name   | Rows  | Bytes | Cost (%CPU)| Time     |
----------------------------------------------------------------------------
|   0 | SELECT STATEMENT  |        |     1 |     4 |     0   (0)| 00:00:01 |
|*  1 |  INDEX UNIQUE SCAN| PK_EMP |     1 |     4 |     0   (0)| 00:00:01 |
----------------------------------------------------------------------------

Predicate Information (identified by operation id):
---------------------------------------------------

   1 - access("EMPNO"=TO_NUMBER(:BVAR))

But the fact that ADF view criteria where clause is applied after the main query block will have a huge performance impact in case you end up using a analytical function inside your query block as shown below.

select * from (select empno,row_number() over (order by 1) from emp) QRSLT where empno=2;

The query plan is shown below

PLAN_TABLE_OUTPUT
--------------------------------------------------------------------------------
Plan hash value: 1674134785

----------------------------------------------------------------------------
| Id  | Operation         | Name   | Rows  | Bytes | Cost (%CPU)| Time     |
----------------------------------------------------------------------------
|   0 | SELECT STATEMENT  |        |    14 |   364 |     1   (0)| 00:00:01 |
|*  1 |  VIEW             |        |    14 |   364 |     1   (0)| 00:00:01 |
|   2 |   WINDOW NOSORT   |        |    14 |    56 |     1   (0)| 00:00:01 |
|   3 |    INDEX FULL SCAN| PK_EMP |    14 |    56 |     1   (0)| 00:00:01 |
----------------------------------------------------------------------------

Predicate Information (identified by operation id):
---------------------------------------------------

   1 - filter("Q1"."EMPNO"=2)

Without view criteria

The query is shown below :-

select empno,row_number() over (order by 1) from emp where empno=:bvar

The execution plan :-

PLAN_TABLE_OUTPUT
-----------------------------------------------------------------------------------
Plan hash value: 1807209526

-----------------------------------------------------------------------------
| Id  | Operation          | Name   | Rows  | Bytes | Cost (%CPU)| Time     |
-----------------------------------------------------------------------------
|   0 | SELECT STATEMENT   |        |     1 |     4 |     0   (0)| 00:00:01 |
|   1 |  WINDOW NOSORT     |        |     1 |     4 |     0   (0)| 00:00:01 |
|*  2 |   INDEX UNIQUE SCAN| PK_EMP |     1 |     4 |     0   (0)| 00:00:01 |
-----------------------------------------------------------------------------

Predicate Information (identified by operation id):
---------------------------------------------------

   2 - access("EMPNO"=TO_NUMBER(:BVAR))

Now this plan is far better as it will firstly filter the rows and then the analytical function row_number() will be applied. You can see that in the plan output that the rows that need to be accessed are 14 (all the rows) and a full index scan (all the index blocks are going to be visited) is going to take place.

The plan output differs due to the fact that whenever you are using analytical function or a rownum clause inside your query. The query optimizer will not push predicates to the inner query block because it can effect the result set returned by the query. While in the former case the query optimizer will push the predicates inside hence execution plans are same.

Hence if you are using analytical functions or a rownum clause in your query be aware of the performance impact and always filter the rows inside.

Note:Also don't choose to ignore null values for predicates that are required and create proper indexes on the table structure depending upon how you filter results. For ex: If predicate is upper(ename)=upper(:bvar) then create a index on upper(ename) .

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Handling Browser Close Event in ADF

In this post i would discuss a simple workaround to the fact that ADF 11g does not support a explicit window close event. The workaround is to use a library like dojo or jquery. One should use these libraries as it will make the function cross browser compatible.

The code mentioned below logs the user out when they press the close button on browser. It essentially calls the unLoad function which makes the use of dojo.io.script.get function (this dojo function also allows cross site data access using callbacks).

<script type="text/javascript" src="http://ajax.googleapis.com/ajax/libs/dojo/1.4/dojo/dojo.xd.js" ></script>
<script type="text/javascript">
dojo.require("dojo.io.script");
var unLoad = function() {
    dojo.io.script.get({
    url:'http://127.0.0.1:7101/myapp/adfAuthentication?logout=true',
    timeout:15000,
    });
 
 
  }
  dojo.addOnWindowUnload(unLoad);
</script>

Add this code in the fragment or the jspx page. Also note that if you are adding it in a fragment make sure to add the script in a af:panelFormLayout.

Note: The documentation states the following.

However, you need to be careful about what work you do during dojo.addOnUnload/window.onbeforeunload since 
this event can be triggered if the user 
clicks a link to download a file or a javascript: link. 
In these cases, the document will not be destroyed 
and so any destructive operations done 
during a dojo.addOnUnload callback may be premature.

Therefore you will have to ignore such events by using something like this.

<script type="text/javascript">
dojo.require("dojo.io.script");
var doUnload=true;
var unLoad = function() {
if(doUnload){
    dojo.io.script.get({
    url:'http://127.0.0.1:7101/myapp/adfAuthentication?logout=true',
    timeout:15000,
    });
  }
doUnload=true;
  };
var init=function(){
dojo.connect(dojo.doc, "onkeypress", function(e){
   switch(e.charOrCode){
        case dojo.keys.F5: doUnload=false;
        break; 
        case dojo.keys.BACKSPACE: doUnload=false;
        }
 dojo.stopEvent(e); 
});
dojo.connect(dojo.doc, "onclick", function(e){
   doUnload=false;
});

};
dojo.addOnWindowUnload(unLoad);
dojo.addOnLoad(function (){init();});
</script>

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Oracle Database account unlocker

This is a simple procedure i created for unlocking user account and resetting the password to the original password, Although a very small utility it helps you with unlocking accounts that you tend to use after a long time which in my case were the SOA server and the BAM server user accounts.

CREATE OR REPLACE PROCEDURE "SYS"."ACCOUNT_UNLOCKER" ( p_user in varchar2 )
is
temp_password varchar2(255);
begin
select password into temp_password from sys.user$ where upper(name)=upper(p_user
);
execute immediate 'alter user '||p_user||' account unlock ' ;
execute immediate 'alter user '||p_user|| ' identified by values '''||temp_passw
ord||'''';
end;

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Whitepaper on resetting field values in ADF

Following is a technical white paper that shows you how to reset field values in ADF using ADF JavaScript client library.

View/Download

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Error handling in adf

To override the default error handler one can extend the  DCErrorHandlerImpl. In this you can process the exceptions or can choose to suppress them. In this post i will explain a way to suppress the RowValException message and display only the detail entity attribute level exception ie AttrValException.

In ADF the exceptions are grouped and raised together as a single object. For example let's say that 2 of the attributes fail the mandatory validation then the exceptions raised for them will be 2 individual AttrValException these are then attached as detail objects into a RowValException and if there are many such RowValException they will be attached and raised together as a TxnValException.

So now to handle the aforementioned task we need to recursively  process the exceptions and suppress the RowValException message. The snippet below shows that :-

public class MyErrorHandler extends DCErrorHandlerImpl {
    private static final ADFLogger logger = ADFLogger.createADFLogger(VleAdminErrorHandler.class);
    private static ResourceBundle rb = ResourceBundle.getBundle("mypackage.myBundle");
    public MyErrorHandler() {
        super(true);
    }

    public MyErrorHandler(boolean setToThrow) {
        super(setToThrow);
    }

    public void reportException(DCBindingContainer bc, java.lang.Exception ex) {
        disableAppendCodes(ex);
        logger.info("entering reportException() method");
        BindingContext ctx = bc.getBindingContext();
        String err_code;
        err_code = null;
        if(ex instanceof NullPointerException){
              logger.severe(ex); 
              JboException e = new JboException(rb.getString("STANDARD_ERROR_MESSAGE"));
              super.reportException(bc, e);
            }
        else if(ex instanceof RowValException){
          
          Object[] exceptions= ((RowValException)ex).getDetails();
          if(exceptions!=null){
            for(int i=0;i<exceptions.length;i++){
                  if(exceptions[i] instanceof RowValException){
                       this.reportException(bc, (Exception)exceptions[i]);                                 
                  }
                  else if(exceptions[i] instanceof AttrValException){
                super.reportException(bc, (Exception)exceptions[i]);
                  }
              }
          }
            else{
            this.reportException(bc, ex);
            }
            
        }
       else if (ex instanceof TxnValException) {
          Object[] exceptions= ((TxnValException)ex).getDetails();
          if(exceptions!=null){
          for(int i=0;i<exceptions.length;i++){
              if(exceptions[i] instanceof RowValException){
                   this.reportException(bc, (Exception)exceptions[i]);                                 
              }
              else{
            super.reportException(bc, (Exception)exceptions[i]);
              }
          }
          }
          else {
                super.reportException(bc, ex);
              }
        }
      
       else if (ex instanceof oracle.jbo.DMLException) {
           JboException e = new JboException(rb.getString("STANDARD_ERROR_MESSAGE"));
            super.reportException(bc, e);
        }
       else if(ex instanceof javax.xml.ws.WebServiceException){
            JboException e=new JboException(rb.getString("WEB_SERVICE_EXCEPTION"));
            super.reportException(bc, e);
            }
       
        else if (ex instanceof JboException) {
            super.reportException(bc, ex);
        }

    }


    public static FacesMessage getMessageFromBundle(String key, FacesMessage.Severity severity) {
        ResourceBundle bundle = ResourceBundle.getBundle("sahaj.apps.vleadministration.view.resources.VLEAdministrationUIBundle");
        String summary = JSFUtil.getStringSafely(bundle, key, null);
        String detail = JSFUtil.getStringSafely(bundle, key + "_detail", summary);
        FacesMessage message = new FacesMessage(summary, detail);
        message.setSeverity(severity);
        return message;
    }
  private void disableAppendCodes(Exception ex) {
      if (ex instanceof JboException) {
        JboException jboEx = (JboException) ex;
        jboEx.setAppendCodes(false);
        Object[] detailExceptions = jboEx.getDetails();
        if ((detailExceptions != null) && (detailExceptions.length > 0)) {
          for (int z = 0, numEx = detailExceptions.length; z < numEx; z++) {
            disableAppendCodes((Exception) detailExceptions[z]);
          }
        }
      }
  }
  @Override  
    protected boolean skipException(Exception ex) {  
      if (ex instanceof JboException) {  
        return false;  
      } else if (ex instanceof SQLIntegrityConstraintViolationException) {  
        return true;  
      }  
      return super.skipException(ex);  
    }

    @Override
    public String getDisplayMessage(BindingContext bindingContext,
                                    Exception exception) {
        return super.getDisplayMessage(bindingContext, exception);
    }

    @Override
    public DCErrorMessage getDetailedDisplayMessage(BindingContext bindingContext,
                                                    RegionBinding regionBinding,
                                                    Exception exception) {
        
        
    return super.getDetailedDisplayMessage(bindingContext, regionBinding, exception);
    }
} 

In this snippet i am recursively processing TxnValException->RowValException -> AttrValException. The AttrValException is being passed in the super call to the DCErrorHandlerImpl to process and display the message.

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