March 6, 2015

Git - Useful Commands - 2

Git Verify a Pull Request Locally

Before merging a pull request to your repository, it is best to verify the pull request locally. Therefore, do the following :

$git fetch origin pull/X/head:pullX

Replace X with the pull request number. Here we assume that you are directly working on the repository the pull request was sent to. Now a new branch is created in your local repository as pullX and it contains the changes of the pull request. Now you need to merge this with the current branch or any other branch to verify. Assuming you want to merge to master branch,

$git checkout master

$git merge pullX

Now you can verify the pull request and decide on the next step for committing.

Git Verify a Pull Request of Non Default Repository Locally

Assume you are on repository A. The pull request has been sent to repository A2. A2 is a fork of A. 
Now, you will have to do the following :

$git remote add upstream [url to A2]

This will add A2 as a remote branch referred by upstream.

Now you can fetch the pull request same like before using :

$git fetch upstream pull/X/head:pullX

Notice that, now you are fetching the pull request from the upstream repository. Rest of the process is same as above. 

Git Rollback a Pushed Commit
$git reset --hard <old-commit-id>
$git push -f origin <branch>

Git Rollback Last Pushed Commit
$git reset HEAD^ --hard
$git push -f origin <branch>

Git Remove a File from Last Commit
If you mistakenly committed a file and you want to remove it from your last commit, do the following : 

Checkout the required commit version of the particular file. If it is a new file, it is okay to remove the file with "rm"
$git checkout <commit_id> <path_to_file>

Now amend the commit
$git commit --amend

If you have already pushed your commit,
$git push -f origin <branch>

Amend Last Commit
--amend option can be used to modify last commit in anyway. Example : modify a file, add a missed file, change commit message, etc.

If you do not want to change the commit message,
$git commit --amend --no-edit

March 2, 2015

WSO2 ESB - Running Integration Tests

Integration tests for WSO2 ESB is available in product-esb repository at

You can clone this module and build ESB product with mvn clean install. The product will be created in [PRODUCT_ESB]/modules/distribution/target folder as wso2esb-[version].zip file.

This will also run all the integration tests for the product and you can find the surefire reports for the product at [PRODUCT_ESB]/modules/integration/tests-integration/[relevant_module_folder]/target/surefire-reports folder.

If you are executing tests by module, you can navigate to the relevant module and issue mvn clean install. However, before doing so, issue a mvn clean install -Dmaven.test.skip=true at product-esb level, to create the distribution pack. At test execution time, the test framework extracts this pack and starts the ESB server to deploy the required artifacts or make the required configuration changes for executing the tests.

Make sure you shutdown any running instances of a WSO2 product or a Axis2 Server instance or any other before running the tests, as it might interrupt with the servers that will be started and stopped during test execution.

Debugging Integration Tests

In order to debug integration tests, do the following :
  1. Navigate to required module or product-esb folder and issue mvn clean install -Dmaven.surefire.debug
  2. Notice the following in console :
    Listening for transport dt_socket at address: 5005
  3. Now click on debug button or Run>Debug in IntellijIDEA or Eclipse (Notice that you need to do a remote debugging here. Refer )
  4. You can apply breakpoints, watch expressions as you would in any normal debug scenario

Useful TestNG Tips

These integration tests use TestNG as the test engine.

Test suites and test cases to be run is included in the testng.xml. This testng.xml file can be found at [PRODUCT_ESB]/modules/integration/tests-integration/[relevant_module_folder]/src/tests/resources/testng.xml.

The tests can be included in package level or classes or even method level. Tests can also be excluded in debug Refer [1] to read up on TestNG. Following are some useful tips on TestNG.

1. To define a new test suite, add the following within <suite> tag of testng.xml :
   <test name="[TestSuite name]" preserve-order="true" verbose="2">
            <package name="[package containing tests]"/>

set preserver-order to true, if you want to run the tests in the order specified in package or classes.

2. Instead of package, if you want to add classes :
   <test name="[TestSuite name]" preserve-order="true" verbose="2">
            <class name="[fully qualified class name]"/>
            <class name="[fully qualified class name]"/>
            <class name="[fully qualified class name]"/>

3. If you want to add specific test methods of a class :
  <test name="[TestSuite name]" preserve-order="true" verbose="2">
            <class name="[fully qualified class name]"/>
                    <include name="[test method name]" />
                    <include name="[test method name]" />

4. If you want to exclude specific methods of a class :
  <test name="[TestSuite name]" preserve-order="true" verbose="2">
            <class name="[fully qualified class name]"/>
                    <exclude name="[test method name]" />
                    <exclude name="[test method name]" />

4. You can exclude or include all test methods by using ".*" as regex value for name :
    <exclude name=".*" />
    <include name=".*" />

5. To disable a test suite, use enabled property (true/false) :
    <test name="[TestSuite name]" preserve-order="true" verbose="2" enabled="false">

6. The test suites run in the order specified in the testng.xml. However, the order of the surefire report is different to this

7. Test methods can be identified by @Test annotation in the Java class

8. You can also disable test methods in Java class
    @Test(groups = {"wso2.esb"}, description = "...", enabled = false)
    public void testMethod() {
Refer next post for notes on writing ESB integration tests.

Reference : 

February 22, 2015

Using Code Formatter for Blogger

Wordpress have a <code> tag to wrap code segments, but this is not so in blogger. So when I migrated from wordpress to blogger, all the formatting and syntax highlighting had to be redone.

I used SyntaxHighlighter [1] for this.

Step 1 :

First step is to add required css and javascript to the blogger template. So whatever template you have chosen, go to your Blogger Home > Template > Edit HTML

Step 2 :

Add the following within <head> tag

<!-- BEGIN SyntaxHighlighter BEGIN -->

<link href='' rel='stylesheet' type='text/css'/>

<link href='' rel='stylesheet' type='text/css'/>

<script src='' type='text/javascript'/>

<script src='' type='text/javascript'/>

<script src='' type='text/javascript'/>

<script src='' type='text/javascript'/>

<script src='' type='text/javascript'/>

<script src='' type='text/javascript'/>

<script src='' type='text/javascript'/>

<script src='' type='text/javascript'/>

<script src='' type='text/javascript'/>

<script src='' type='text/javascript'/>

<script src='' type='text/javascript'/>

<script src='' type='text/javascript'/>

<script src='' type='text/javascript'/>

<script src='' type='text/javascript'/>

<script src='' type='text/javascript'/>

<script src='' type='text/javascript'/>

<script src='' type='text/javascript'/>

<script language='javascript' type='text/javascript'>

    SyntaxHighlighter.config.bloggerMode = true;



<!-- END SyntaxHighlighter END -->

Step 3 : Writing blog posts

In your blog posts, go to HTML view and wrap all your code segments with a <pre> tag as below,

<pre class="brush:java">

System.out.println ("Using Syntax Highlighter");


Below is the real preview of the above:

System.out.println ("Using Syntax Highlighter");
For more info on SyntaxHighlighter configurations, visit [2]

Reference :

February 13, 2015

Apple Script to copy a file repeatedly

Open Apple Script Editor and add the following script and hit run button.

set theFile to "Macintosh HD:Users:maheeka:original_file:test.xml"
set theDestinationFolder to "Macintosh HD:Users:maheeka:test_des"

repeat 10 times
tell application "Finder"
duplicate theFile to theDestinationFolder with replacing
end tell
delay 2
end repeat

Note :
  • Always use an alias for the file location
  • File path should be separated with : and not /

January 28, 2015

Remove 3rd Party Apps in OSX

Removing apps installed on OSX via App Store is very easy. You just have to go to LaunchPad tap and hold on the icon of the app you want to uninstall until a small cross appears on the top right corner. Click on this cross and you can uninstall the app.

However, for 3rd party apps where you either downloaded a .dmg and installed or however, it is not that straightforward. So in order to do that you can do the following. 

Example : 

Maheekas-MacBook-Pro:~ maheeka$ mdfind -name mackeeper
/Users/maheeka/Library/Application Support/MacKeeper Helper

This lists down all folders and files in the system with name as "mackeeper". Delete each of these folders and files. 

Local FTP Server on OSX

To start a local FTP server : 
$ sudo -s launchctl load -w /System/Library/LaunchDaemons/ftp.plist

To stop local FTP server : 
$ sudo -s launchctl unload -w /System/Library/LaunchDaemons/ftp.plist

To connect to FTP server : 
Maheekas-MacBook-Pro:~ maheeka$ ftp localhost
Trying ::1...
Connected to localhost.
220 ::1 FTP server (tnftpd 20100324+GSSAPI) ready.
Name (localhost:maheeka): maheeka
331 User maheeka accepted, provide password.
230 User maheeka logged in.
Remote system type is UNIX.
Using binary mode to transfer files.


Once connected, most of normal file system related commands will work similarly.

ftp> pwd
Remote directory: /Users/maheeka
ftp> mkdir test
257 "test" directory created.
ftp> cd test
250 CWD command successful.
ftp> mkdir newfolder
257 "newfolder" directory created.
ftp> ls
229 Entering Extended Passive Mode (|||50051|)
150 Opening ASCII mode data connection for '/bin/ls'.
total 0
drwxr-xr-x  2 maheeka  staff  68 Feb  1 10:02 newfolder
226 Transfer complete.
ftp> pwd

Remote directory: /Users/maheeka/test

For a complete reference of ftp commands refer :

To access FTP Server from browser :

Type ftp://username:password@localhost/ on address bar.

Reference : 

November 13, 2014

Remote Debugging WSO2 ESB with IntellijIdea and Eclipse

This post assumes you are familiar with debugging concepts. The remote debugging will be explained using WSO2 ESB product.

What happens in remote debugging is that the debugging information of a running application is communicated with an IDE that has the source of the application. The application is not running from the source, and thus the term "remote" debugging. Similar to any normal debug scenario, where you would be running the application in debug mode from the IDE, you can have breakpoints, watch expressions, etc.

Read more about how remote debugging works in JVM at [1].

Let's proceed on how to debug WSO2 ESB.

Setup the Source for Debugging WSO2 ESB

There are a number of components in WSO2 stack that contribute to the complete WSO2-ESB product. Some of these components are : wso2-synapse, carbon-mediation, wso2-axis2-transport, carbon4-kernel, etc. You can download source of all these components at

Decide on the component(s) you need to debug, and import them to your preferred IDE (Eclipse or IntellijIdea). To do this :
  1. Clone the required component from the git repository : git clone <repository_url>
  2. Build the component : mvn clean install or mvn clean install -Dmaven.test.skip=true (to skip tests)
  3. To setup as an IDE project : mvn idea:idea (for IntellijIdea) or mvn eclipse:eclipse (for Eclipse)
  4. Add breakpoints as needed
  5. If debugging multiple components, 
    • Eclipse : Import as project to the same workspace and add breakpoints
    • Idea : Import as module to the same window and add breakpoints
    • Optionally, at the time of debug, when debugging takes you to the .class files, you can attach the relevant components as sources with "attach source" option and continue.
Note : 
If you want to debug message flow on ESB, add a breakpoint to receive(org.apache.axis2.context.MessageContext mc) method in org.apache.synapse.core.axis2.ProxyServiceMessageReceiver class in wso2-synapse. This is the start point to the message flow on ESB.

Remote Debugging WSO2-ESB

Step 1 : Start WSO2-ESB in debug mode

$ sh bin/ debug 5005
Please start the remote debugging client to continue...
JAVA_HOME environment variable is set to /System/Library/Java/JavaVirtualMachines/1.6.0.jdk/Contents/Home
CARBON_HOME environment variable is set to /Users/maheeka/wso2esb-4.8.1
Listening for transport dt_socket at address: 5005

We have started the ESB in debug mode, and it listens now on port 5005 for a remote debugging client. 

Step 2 : Start Remote Debugging Client (IDE)

  1. Run > Edit Configurations
  2. On the left panel, click on "+" and add a new Remote Configurations. Notice the port to be same as you give when starting ESB.
  3. Then Run > Debug 'wso2-synapse' to start the listener
  4. The application will now run as normal and stop at the breakpoints you have added

  1. Run > Debug Configurations
  2. Add a new Remote Java Application Configuration. Notice the port number to be same as you give when starting ESB.
  3. Click on Debug to start debugging 

November 10, 2014

Building WSO2 ESB 4.8.1 from source in OSX

WSO2 products are all built on top of WSO2 Carbon Kernel. This is the common ground for all products. Turing is the platform release name for WSO2 Carbon 4.2.0 and WSO2 ESB 4.8.1 is based on turing. Not all products of the WSO2 platform does not get released at the same time. Therefore, these products are released in chunks. ESB 4.8.1 comes under chunk 7 of the turing platform. Refer the release matrix to get more info on this [2].
Prerequisites : 
1. Install Java 1.6 and Maven 3
       If you have only 1.7 installed, you will have to install 1.6 on OSX. Unfortunately, there is no direct installation for 1.6. But this sorted out for me  since jdk 1.6 was automatically installed when I installed IntellijIdea
       At the moment, all WSO2 products are compiled on Java 1.6 and is supported up to 1.7. This is why we need to build the source on 1.6.
2. Checkout Source (Orbit, Kernel, Platform)

Building the Source : 

Start building in order Orbit > Kernel > Platform (chunk 07) repos respectively.

To build ESB 4.8.1, you need to build wso2carbon-platform/product-releases/chunk-07 as Platform in above.

The distribution will be created in :


When building, since it will take a lot of time, and to avoid unit test failures from building the product, skip unit tests when building.

mvn clean install -Dmaven.test.skip=true

Build ESB only :

If you need to build only ESB, build at wso2carbon-platform/products/esb with mvn clean install -Dmaven.test.skip=true

Another option is to comment out other product modules in platform/trunk/pom.xml and rebuilding in Orbit > Kernel > Platform in order.

Encountered Errors : 
  1. WSS4 maven install fails > You need to compile in Java 1.6
  2. [WARNING] Error injecting: org.apache.maven.reporting.exec.DefaultMavenReportExecutor > Set maven-site plugin version to 3.3 in all places [4]
Environment : 

October 26, 2014

Grep - Find a text in file (Unix/Linux)

To find the text files containing a particular string :

grep -l "maheeka" *.txt

Search in current directory :
grep -lr "maheeka" . 

To view the occurrences of the string in the files, use without "-l" option


October 15, 2014

Find and Duplicate with Regex in Notepad++

In order to duplicate a text (instead of find and replace, find and duplicate) use regex feature provided with Notepad++ as follows.

Assume the following content in an XML :
 <person firstname="ann" /> 
Now lets convert this to following :
<person firstname="ann" nickname="ann"/>
So to do the above you need to do as below.
  • Go to Find and Replace window
  • In Find text enter : firstname="(.*)"
  • In Replace with text enter : firstname="\1" nickname="\1"

March 2, 2014

Git - Useful Commands

Commit Changes without Staging Stage : 
$ git commit -a -m "committing without staging"

To Push to a Branch : 

Assuming a branch is created and checked out :
git push origin branch

If pushing to a non-default branch, you need to specify the source ref and the target ref :
git push origin branch1:branch2

Fetch from Original Forked Repository or any other Related Repository : 

First you need to add the desired repository as a remote :

$ git remote add upstream

This remote will be referred to as 'upstream' now. Then you can fetch from this upstream. You can verify the added remote repositories as below :

$ git remote -v
origin (fetch)
origin (push)
upstream (fetch)
upstream (push)

Now merge the changes to the local branch :
$ git merge upstream/master master

upstream/master is the upstream branch that you need to merge from and master is your local branch. If you are merging to another branch use that branch name instead of master.
$ git merge upstream/branch branch

Now push these commits to your repository :
$ git push origin master

Checkout a Branch from Upstream :

Create a branch tracking upstream branch and checkout :
$ git checkout -b branch1 upstream/branch1
Branch branch1 set up to track remote branch branch1 from upstream.
Switched to a new branch 'branch1'

Now you can commit and push as you would for any other branch.

Edit Committed (and Pushed) Commit Message : 
  1. $git commit --amend -m "new commit message"
  2. $git push origin master -f

Adding an Existing Project to git (bitbucket) :
  1. Create a project in bitbucket - you will get "clone url"
  2. Issue the following commands on git bash :

Initialize git repository : 
leo@LEODEN ~ $ git init Initialized empty Git repository in C:/Users/leo/.git/ 

Navigate to the project location
leo@LEODEN ~ (master) $ cd C:/Users/leo/git/timesheetApp/TimeSheet 

Initialize existing git repository
leo@LEODEN ~/git/timesheetApp/TimeSheet (master) $ git init Reinitialized existing Git repository in c:/Users/leo/git/timesheetApp/TimeSheet /.git/

Add(Stage) all files and folders
leo@LEODEN ~/git/timesheetApp/TimeSheet (master) $ git add * 

Check status (optional) which will list down the files to be committed
leo@LEODEN ~/git/timesheetApp/TimeSheet (master) $ git status 
# On branch master # 
# Initial commit # 
# Changes to be committed: 
# (use "git rm --cached <file>..." to unstage) # 
# new file: .classpath 
# new file: .project 
# new file: .settings/org.eclipse.jdt.core.prefs 
# new file: .settings/org.eclipse.jdt.ui.prefs .....

Commit the staged
leo@LEODEN ~/git/timesheetApp/TimeSheet (master) $ git commit -m "first project add" [master (root-commit) 71447ea] 
first project add 56 files changed, 707 insertions(+) 
create mode 100644 .classpath 
create mode 100644 .project ..... 

Check the status (optional) which will show that all are committed
leo@LEODEN ~/git/timesheetApp/TimeSheet (master) $ git status 
# On branch master nothing to commit, working directory clean 

Push the changes to bitbucket repository
leo@LEODEN ~/git/timesheetApp/TimeSheet (master) $ git push -u origin master 
Password for '': 
Counting objects: 90, done. Delta compression using up to 4 threads. 
Compressing objects: 100% (71/71), done. 
Writing objects: 100% (90/90), 1.47 MiB | 14 KiB/s, done. 
Total 90 (delta 5), reused 0 (delta 0) To * [new branch] master -> master Branch master set up to track remote branch master from origin.

Reference : 

August 16, 2012

Access outer class members from inner class

The following example shows how to access outer class members from inner class
public class OuterClass{

   public void method() {
      //do something

   class InnerClass {

      public void innerMethod() {
         //do something

August 8, 2012

Right align tabs in JTabbedPane

Some useful tips for aligning tabs in JTabbedPane :-

Align tabs to right
Place tabs on right of the JTabbedPane


August 7, 2012

Java Swing UI Settings

To set global UI settings in Java Swing, use UIManager and set the properties as needed. All components have their respective keys and default values. For a complete list of properties, refer

These settings should be done before creating the JFrame where all these components are put into.

Example :
UIManager.put("Button.background", Color.RED);
UIManager.put("Button.font", new FontUIResource(new Font("Arial", Font.BOLD, 12)));

July 23, 2012

OLE Exception in Eclipse for MSOffice files

If you have got the above error message when you try to open a MS Office file in eclipse, that means your OLE editor is not working in eclipse. When i googled I found that this is a common problem for Excel files. So I suggest to set the Excel files to open in Excel editor instead of OLE editor. So, do the following ;

  1. Go to Eclipse -> Window -> Preference -> General -> Editors -> File Associations

  2. Add the .xls file type (or any other file type you want)

  3. Choose the Excel WorkBook 97-2003 WorkSheet (or any other file editor you want)

  4. Click OK-> OK

  5. Now the .xls file will opens in Ms Excel

July 4, 2012

JDOM Document to String

XMLOutputter outputter = new XMLOutputter(Format.getPrettyFormat());
String scenarioStr = outputter.outputString(jdomDoc);

Reference :

June 29, 2012

Java Varargs - Unlimited parameters to a Java method

When you cannot decide the number of parameters you need for a method, varargs becomes the solution. Earlier, if we couldn't determine such, we had to use a collection as a parameter to help with this scenario. But varargs simplifies this.

Varargs does use an array underneath, but using varargs syntax hides the process.

public static String format(String pattern,
                                Object... arguments);

Example :

If you need to write a file name extension filter for a number of extensions, you can use this method of defining the method.

public FileNameExtensionFilter(String description, String... extensions) {

Read more on varargs at :

JFileChooser - Useful Tips

Set Starting Directory
JFileChooser fileSaver = new JFileChooser();
String cpath = "C:/MWork/Test1/script/";
File f1 = new File(cpath);

File Filter
FileNameExtensionFilter filter = new FileNameExtensionFilter("eXtensible Markup Language file (*.xml) ", "xml");
fileSaver .setFileFilter(filter);

Default File Save Name
jFileChooser.setSelectedFile(new File("untitled.xml"));