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Showing posts from July, 2015

Selenium - Use Explicit Waits for checking elements quickly disappear like loading icon

I have a table that is displayed a list of competence groups. When I click on a competence group, it will display a table that contains a lot of criteria belong to the competence group. Each times I click on a competence group, a "loading" icon is displayed while waiting for all criteria is fully displayed.

<div id="loading" style="display: none;"> <div></div> <div></div>
I tried to write a Selenium test to make sure this behavior is covered. I saw that the loading icon element is always available on DOM tree because I just used Jquery to handle its displaying. Beside that, the loading icon is appeared dynamically and quickly disappear afterwards. It is hard to checking the visibility on GUI of loading icon. By normal way that I frequently used, the code looks like:

public boolean isLoadingIconDisplayed() { List<WebElement> loadingIcons = driver.findElements("loading")); if(!loadingIcons.isEmpty())…

Junit - Test fails on French or German string assertion

In my previous post about building a regex to check a text without special characters but allow German and French. I met a problem that the unit test works fine on my machine using Eclipse, but it was fail when running on Jenkins' build job.

Here is my test:

@Test public void shouldAllowFrenchAndGermanCharacters(){ String source = "ÄäÖöÜüß áÁàÀâÂéÉèÈêÊîÎçÇ"; assertFalse(SpecialCharactersUtils.isExistSpecialCharater(source)); }
Production code:

public static boolean isExistNotAllowedCharacters(String source){ Pattern regex = Pattern.compile("^[a-zA-Z_0-9_ÄäÖöÜüß áÁàÀâÂéÉèÈêÊîÎçÇ]*$"); Matcher matcher = regex.matcher(source); return !matcher.matches(); }
The result likes the following:
Failed tests: SpecialCharactersUtilsTest.shouldAllowFrenchAndGermanCharacters:32 null
A guy from says:

"This is probably due to the default encoding used for your Java source files. The ö in the string literal in the JUnit source code …

Regex - Check a text without special characters but German, French

Special characters such as square brackets ([ ]) can cause an exception "java.util.regex.PatternSyntaxException" or something like this if we don't handle them correctly.

I had met this issue. In my case, my customers want our application should allow some characters in German and French even not allow some special characters.

The solution is that we limit the allowed characters by showing the validation message on GUI. For an instance, the message looks like the following:

"This field can't contain any special characters; only letters, numbers, underscores (_), spaces and single quotes (') are allowed."

I used Regular Expression to check it. For entering Germany and French, I actually don't have this type of keyboard, so I referred these sites:

* German characters: * French characters:
Here is my code:
package vn.nvanhuong.practice; import java.util.regex.Matcher; import java.util.regex.Pattern; …

Tip for resolving the compile errors when importing a Maven project in Eclipse

Sometimes, I import a existing Maven project into Eclipse and I get some compile errors related to "pom.xml", "facet version of Web", and  so on. It was really frustrating me because I even cleaned, built and updated the project many times but the errors still occurred.

I accidentally found the following steps to resolve this issue but honestly I still don't know why.

Step 1: Delete the project that met the compile errors in Eclipse, but don't delete it on disk.

Step 2: Open the project (by Windows Explorer if you use Windows) and remove  file/folder ".classpath", ".settings" and ".project" .

Step 3: Import the project back into Eclipse.

Maven is a build automation tool used primarily for Java projects.
Eclipse is an integrated development environment (IDE).

No difficulties, no discovery

Bill Gate had said that “I choose a lazy person to do a hard job. Because a lazy person will find an easy way to do it.” In my opinion, that remark is so true in some cases. My team has tried to apply integration tests for our projects. Firstly, we had meeting to figure out what problems we met. Then, we decided to create a new project that is similiar to the current one and we called it a prototype project. Yeah, I and some members were reponsile for it. I spent a lot of time and took a lot of efforts for coppying the current project because its domain logic was really complicated. What a boring task! I smelt a rat and felt too lazy. At that time, I thought that I need a change. I discussed with others: "Why don't we just create a branch of curent project and work on it?". We didn't need spending time for coppying anymore. Just forked it and modified on it. Therefore, it was really a good solution.

Leave your comments about that. ;)

How did you fix the hardest bug that you have ever seen?

"Holy shit"

Have you ever fixed a feature that has a lot of issues? I had met this situation. I would like to tell you my process to deal with it.

My problem: Fixing the wrong validation after hitting the F5 on a page.

Step 1. List out all of issues that I met on this feature.

Yeah, after hitting F5, I got:
- The validation dialog could not be closed.
- The data of the page could not be reverted the previous data.
- I wonder why it automatically called the new select event on the combobox on the page?

Step 2. Fix the problem: issue by issue, simple to complicated.

- Try to close the dialog -> solved
- Try to revert the previous data -> solved
- Try to fix the last issue -> I was so confused about this case. I spent haft day find the root caused but I could not solve it. I decided go to step 3.

Step 3. Tell to other members about my problems. Discussing for the win!

There are six people in the discussing. We had a lot of guessing, a lot of investigating, a lot of ideas,…

How to convert time between timezone in Java, Primefaces?

I use the calendar Primefacescomponent with timeOnly and timeZone attributes for using only hour format (HH:mm). Like this:
<p:calendar id="xabsOvertimeTimeFrom" pattern="HH:mm" timeOnly="true" value="#{data.dateFrom}" timeZone="#{data.timeZone}"/> We can convert the value of #{data.dateFrom} from GMT/UTC time zone to local, conversely, from local time zone to GMT/UTC time zone. Here is my functions:
package vn.nvanhuong.timezoneconverter; import java.text.ParseException; import java.text.SimpleDateFormat; import java.util.Calendar; import java.util.Date; import java.util.TimeZone; public class TimeZoneConverter { /** * convert a date with hour format (HH:mm) from local time zone to UTC time zone */ public static Date convertHourToUTCTimeZone(Date inputDate) throws ParseException { if(inputDate == null){ return null; } Calendar calendar = Calendar.getInstance(); calendar.setTime(inputDate); int hours…