10 Ağustos 2015 Pazartesi

creating ant file for eclipse project

Sometimes you need an ant build file for an existing Eclipse project, for instance when moving it to jenkins.. The easy way to do it is as follows:
on Eclipse click on File -> Export -> General -> Ant Buildfiles and specify the wanted fields.
It does not automatically have a war target, so have to add it.

8 Temmuz 2015 Çarşamba

selenium quickstart tips

By using Selenium (http://www.seleniumhq.org/), you can automate browsers and it is a good practice to use the tool to do some integration testing.. There are many tutorials about this on the web, the following worked for me:
Absoft Training presents more tutorials here: http://www.absofttrainings.com/selenium-training-free-videos/ 

My usage tips :
  • Download Selenium standalone server and the java client.
  • In Eclipse create a java project and add the downloaded jars (must be 2 jars) to classpath.
  • Download Selenium IDE and install it as Firefox plugin.
  • Run the server and deploy your application to test.
  • Open Firefox, start Selenium IDE, press record button and enter your web application url.
  • Test your application, one use case at a time.
  • Close Selenium recording, save it and export test case as Java / Junit 4/ WebDriver.
  • I did not use the immediately exported files. But, i got help from them. I think preparing a utility file which enables you to switch between browser types, between development and production environments is convenient. If you have a complicated web page, it is good practice to write find methods for web elements and reuse them.
  • Then run tests as junit.
Some technical tips:
  • WebDriver interface provides many methods including findElement(), getTitle(), close(), getCurrentUrl() etc. It is good to examine its javadoc.
  • You can locate a web element by id, name or xpath.
  • To create Firefox driver, simply :
    • WebDriver driver = new FirefoxDriver();
  • To create Chrome driver, download the third party executable
    • System.setProperty("webdriver.chrome.driver", "path_to_executable");
    • WebDriver driver = new ChromeDriver();
  • To create IE driver, download the third party executable
    • System.setProperty("webdriver.ie.driver", "path_to_executable");
    • WebDriver driver = new InternetExplorerDriver();
  • To make same arrangements:
    • driver.manage().timeouts().implicitlyWait(60, TimeUnit.SECONDS);
    • driver.manage().window().maximize(); // maximizes opening browser
  • Selenium sees everything on a web page as web element.
  • findElement retrieves first one that matches
  • findElements retrieves all elements that match
  • You can locate by
    • Id
    • Name
    • LinkText (text of hyperlink)
    • PartialLinkText
    • Xpath (ultimate solution, when others don't work)
      • ByXpath("//input[@placeholder='Email']") means locate an input field whose placeholder attribute value is Email.
    • CssSelector
    • TagName
    • ClassName
  • Locating by Xpath
    • Xpath-Absolute: not recommended.
      • //html/body/tag1[index]/..
    • Xpath-Attributes: best when can't use id or name
      • //input[@id='Pass' and @placeholder='Password']
      • //input[contains(@id, 'user')] 
      • //input[starts-with(@id, 'user')] 
      • Selenium IDE and Firefox developer tools can help to get the xpath of the element.
    • Xpath-Relative: best for table cells
      • //table[@id='xtable']/tbody/tr[3]/td[2]
  • You can make Selenium to wait for the presence of some element:
    • final WebDriverWait wait = new WebDriverWait(driver, 60);
    • wait.until(ExpectedConditions.presenceOfElementLocated(By.id("the_id")));
A test case template:

// create driver for the browser you want
WebDriver driver = new FirefoxDriver();

//open homepage

//find related field, enter some value

//find command button and click

//assert results

6 Temmuz 2015 Pazartesi

mockito with testng suite

When writing tests by mocking your objects, you have to call a method in order to make sure your @Mock annotations really work. This method call is as follows:

In general, we use a BaseTest and call the method there and extend our tests from that BaseTest. Thus, the tests succeed when you run them separately. However, when you call them as suite, you may get the folowing error:
 testClass cannot be null. For info how to use @Mock annotations see examples in javadoc for MockitoAnnotations class  

I tried several approaches to fix this including using MockitoTestNGListener.class, none of which work. Then i find an article advising not to use inheritance in tests (http://www.petrikainulainen.net/programming/unit-testing/3-reasons-why-we-should-not-use-inheritance-in-our-tests/), removing inheritance and calling MockitoAnnotations.initMocks(this);  inside every test class worked :)

18 Haziran 2015 Perşembe

using testng on eclipse

This post provides a quick roadmap to start using testng on eclipse, since there is enourmous amount of documentation on web and it is hard to pick the most relevant ones..

another tip: testng eclipse plugin version 6.9.5... (Update Site - http://beust.com/eclipse) supports JDK7 and 6.8.6 (Update Site - http://beust.com/eclipse-old/eclipse- supports JDK6. 

16 Haziran 2015 Salı

Lucene tip

If you manually delete some files from the lucene index directory, than the next time you try to index you will get an error about the location being OUT-OF-SYNC. The error message may look like something like that:
 Entity com.mypackage.MyEntity Id 12345 Work Type org.hibernate.search.backend.UpdateLuceneWork  
 Entity com.mypackage.MyEntity Id 12346 Work Type org.hibernate.search.backend.UpdateLuceneWork  
 : org.apache.lucene.store.LockObtainFailedException: Lock obtain timed out: NativeFSLock@/path/to/index/com.mypackage.MyEntity/write.lock  
 at org.apache.lucene.store.Lock.obtain(Lock.java:84) [lucene-core-3.5.0.jar:3.5.0 1204425 - simon - 2011-11-21 11:20:12]  
 at org.apache.lucene.index.IndexWriter.(IndexWriter.java:1108) [lucene-core-3.5.0.jar:3.5.0 1204425 - simon - 2011-11-21 11:20:12]  
 at org.hibernate.search.backend.impl.lucene.IndexWriterHolder.createNewIndexWriter(IndexWriterHolder.java:127) [hibernate-search-engine-4.1.0.Final.jar:4.1.0.Final]  
 at org.hibernate.search.backend.impl.lucene.IndexWriterHolder.getIndexWriter(IndexWriterHolder.java:102) [hibernate-search-engine-4.1.0.Final.jar:4.1.0.Final]  
 at org.hibernate.search.backend.impl.lucene.AbstractWorkspaceImpl.getIndexWriter(AbstractWorkspaceImpl.java:119) [hibernate-search-engine-4.1.0.Final.jar:4.1.0.Final]  
 at org.hibernate.search.backend.impl.lucene.LuceneBackendQueueTask.applyUpdates(LuceneBackendQueueTask.java:99) [hibernate-search-engine-4.1.0.Final.jar:4.1.0.Final]  
 at org.hibernate.search.backend.impl.lucene.LuceneBackendQueueTask.run(LuceneBackendQueueTask.java:67) [hibernate-search-engine-4.1.0.Final.jar:4.1.0.Final]  
 at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:471) [rt.jar:1.7.0_03]  
 at java.util.concurrent.FutureTask$Sync.innerRun(FutureTask.java:334) [rt.jar:1.7.0_03]  
 at java.util.concurrent.FutureTask.run(FutureTask.java:166) [rt.jar:1.7.0_03]  
 at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1110) [rt.jar:1.7.0_03]  
 at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:603) [rt.jar:1.7.0_03]  
 at java.lang.Thread.run(Thread.java:722) [rt.jar:1.7.0_03]  

My solution to this situation, is clearing the OUT-OF-SYNC folder content, restart the server and reindex.
More practical solutions may exist, but that worked for me.. By the way, just deleting the write.lock file does not work here..
Another tip about the lock mechanism:
(from http://www.gossamer-threads.com/lists/lucene/java-user/261725 :)

The existence of the write.lock file has nothing to do with actual locking. The lock file is just a placeholder file (0 bytes) on which the lock during indexing is applied (the actual locking is done on this file using a fnctl). When indexing finishes, the lock is removed from this file, but the file stays alive. This was different in Lucene 3, where the lock was also removed. But this caused problems because of non-atomic file operations. Lock factory only checks the "lock on the file", not "the existence of the file as a lock".