Grails: Migrating enum mapping from 1.0 to 1.2 or newer

We have an ongoing long-term web application running on Grails. It started with Grails 1.0.3 and Grails moved on to 1.3.3 in the meantime. Due to time constraints and lack of resources we were not able to update to each new major version. Now, some years later, the time has finally come for us to benefit from all the new features, bugfixes and improvements of the platform. There were quite some changes in behaviour and one of the biggest is the change of how enums are mapped to the database.

In Grails 1.0.x and 1.1.x Java enums were mapped as int values in the database. Starting with Grails 1.2 they are mapped as varchars containing the enum name. Now you have the problem to migrate your existing data over to the new mapping style of the framework. One solution is to use autobase or liquibase migrations to port the enum values for the new mapping style.
Suppose we have the enum Coolness:

pulic enum Coolness {
    COOL, UNCOOL;
}

The SQL for migrating it on the PostgreSQL DBMS looks as simple like this:

alter table foo alter column bar type varchar
    using case when bar = 0 then 'COOL'
            when bar = 1 then 'UNCOOL'
            end

and as an autobase migration it becomes something like this:

changeSet(id: 'change foo bar from int to varchar', author: 'me') {
    preConditions(onFail: "CONTINUE") {
        dbms(type: "postgresql")
    }
    sql("""alter table foo alter column bar type varchar
            using case when bar = 0 then 'COOL'
                    when bar = 1 then 'UNCOOL'
                    end""")
}

We use the precondition to skip our non-persistent in-memory databases we use in development and only apply the change set with persistent test or production databases.

For Oracle and maybe other database systems which do not support altering the column type with the using-clause it may look like

alter table foo add bar_new varchar(255);
update foo set bar_new =
    (case when type = 0 then 'COOL'
            when type = 1 then 'UNCOOL'
      end);
alter table foo drop column bar;
alter table foo rename column bar_new to bar;

I hope this helps when you have to perfom similar migrations some time.

Stay tuned for other changes in API and behaviour between the different Grails framework versions.

Get the basics right

Nowadays with all the fancy stuff around, with features over features, bells and whistles it is even more important to get the basics right.

Nowadays with all the fancy stuff around, with features over features, bells and whistles it is even more important to get the basics right. But what are the basics?
If you apply for a job the first basic would be to read the job posting carefully. Many corporations require you to use a special keyword or cite the reference in a certain way. This is an easy way to avoid that the email ends up in the spam folder and it shows that you can also see who really read the job posting. But many get this wrong. Why? For me that’s one of the basics. Another basic breaker is many or highly visible typos. Once in a while we get some unusual and fancy looking applications with typos in the job title or in headlines. Hmmm.. why bother with time-consuming layouts and colors and have typos all over the place?
This trend can be seen in many places. We have a new and modern door opener. The buttons are in white and pastel colors. Which ruins the contrast. When the light is dim, I cannot make out a difference between the one for opening the door and switching on the light in the hallway. Looking fancy but useless.
The IT business is also good in breaking the basics. In the last weeks some of the major IDEs or frameworks brought out versions which had regression in one of the most basic places: version control. Why didn’t they catch it before release?
Why are features nowadays more important than the basics?

Open Source Love Day July 2010

Our Open Source Love Day for July 2010 brought love for Hudson (especially the CMake and Crap4j plugins), RXTX and JUnit.

This friday , we held our Open Source Love Day for July 2010.  We began with several internal meetings and discussion (like the Homepage Comittee meeting) and dived right in our work afterwards. Everybody had a little backlog of issues that we wanted to get done on this day. Nearly everybody succeeded (well, the author had a minor delay – read about it below). The day went by in a very fast pace, but it felt right.

The Open Source Love Day

We introduced a monthly Open Source Love Day (OSLD) to show our appreciation to the Open Source software ecosystem and to donate back. We heavily rely on Open Source software for our projects. We would be honored if you find our contributions useful. Check out our first OSLD blog posting for details on the event itself.

On this OSLD, we accomplished the following tasks:

  • There are really cool new features in the latest JUnit versions and Rules are one of them. What hurt our aesthetic sense was that the field that hold the Rule instance has to be public. Checkstyle was on our side, so we tweaked JUnit to allow all kinds of visibility. You can read about the change needed here: http://github.com/KentBeck/junit/issues#issue/31. The fix is almost trivial and will hopefully be incorporated in the next versions of JUnit, so we do not publish our altered version.
  • We constantly receive requests and remarks about our cmake plugin for Hudson. This lead to a new version of the plugin fixing two issues with matrix builds and custom build types. Head over to the plugin homepage and grab the new version 1.6. The issues were in detail:
    • The plugin can be used with matrix builds now
    • Custom build types can be defined now
  • RXTX is our choice for serial port communication with Java. We fixed some issues during the last few OSLDs, with one issue left for today: When you flush your stream while using a special type of usb-to-rs232 converter, you got an exception. The corresponding issue is #102 in the RXTX issue tracker. We proposed a patch that fixes the problem.
  • Another hudson plugin is our crap4j reporter. It lacked some love for months now and finally broke when used with the latest hudson versions. Fixing the problem was a lot harder than we thought, basically because the plugin needed adjustments to recent API changes and we couldn’t figure out exactly what adjustments are necessary. You might have a look at the developer mailing list thread for this question. Finally, we got it resolved (on sunday, with a sudden stroke of insight) and a new version 0.8 is published.
  • We use an internal time tracking tool for our projects. This tool isn’t specifically open source yet, but continues to grow in terms of features and usability. The work invested in this tool helps us to continue with the OSLD, so it’s beneficial work nonetheless.
  • During the last OSLD, we had plans for a new hudson plugin and even produced a prototype. This time, we looked around the hudson plugin zoo (it’s getting a bit difficult to keep track of all of them) for inspiration and found a wonderful piece of art: The Groovy Postbuild Plugin. Using this plugin with a small groovy script served our needs exactly. No need for a full-blown plugin when you can scratch your itch with a simple script. Thanks to Serban Iordache for his great work!

What were our lessons learnt today?

  • If you need to setup a fresh workspace for an open source project, consider to prepare it over the night before, or the download delay will kill your precious work time. There is nothing more frustrating than staring at a “downloading…” progress bar while being eager to start programming.
  • Always look around what others have done before. We wanted to build a full hudson plugin from scratch when all we needed was a little groovy script placed inside another plugin. Sweet!
  • Do not hesitate to privately fix open source issues that won’t get done in time for you. Just make sure to have a management process in place to track those changes and be able to re-apply them to future versions. More important though, be able to tell exactly when NOT to re-apply them because the original project has fixed the issue.

Retrospective of the OSLD

The OSLD went smooth and was productive. We tend to work on backlogs instead of searching for random issues now, but that’s just a sign that our approach has matured and we depend on the OSLD to get work done.

Last wednesday, we held our Open Source Love Day for June 2010. This one was productive despite the heat that had us sweating the whole day long (as a sidenote: it got even warmer the days afterwards). Some features were finished and will help at least us in our projects. We still look forward for the right way to release them. Another release was even more problematic, you will read about it below.The Open Source Love Day

We introduced a monthly Open Source Love Day (OSLD) to show our appreciation to the Open Source software ecosystem and to donate back. We heavily rely on Open Source software for our projects. We would be honored if you find our contributions useful. Check out our first OSLD blog posting for details on the event itself.

On this OSLD, we accomplished the following tasks:

Follow-up to our Dev Brunch July 2010

A follow-up to our July 2010 Dev Brunch, summarizing the talks and providing bonus material.

Last Saturday, we held our Dev Brunch for July 2010. The setting of this brunch was unusual, as we didn’t brunch, but cooked spaghetti (to be exact: had spaghetti cooked while we ranted about different workplaces). We also didn’t start in the late morning, but in the early afternoon. Later on, a LAN computer game party was held in our office, limiting our time-frame a bit. Due to rainy weather, we stayed inside and discussed the topics listed below.

The Dev Brunch

If you want to know more about the meaning of the term “Dev Brunch” or how we implement it, have a look at the follow-up posting of the brunch in October 2009. We continue to allow presence over topics. Our topics for the brunch were:

  • Your own Java ResourceBundle implementation – Since Java 6, there is the new possibility to add your own ResourceBundle formats under the generic API using ResourceBundle.Control. We discussed several possible use cases and had an example case mocked up in source code. The API enables you to do what was impossible beforehands but isn’t as polished as it could be. Worth a closer look if you want to combine ResourceBundle with your i18n database, for example.
  • Thoughts on “Team Rooms” – Lately, there was a very good blog entry about team rooms and how they are introduced by Martin Fowler. The article is titled “The rise of the cattle office” and has some valid points. But nearly every attendee of the brunch likes working in a team room. We had a great discussion that can’t be summarized in a single sentence, but one advice: Mr. Fowler, please put up some nicer teaser image in your bliki!
  • Retrospective of the Java Forum Stuttgart 2010 – The Java Forum Stuttgart 2010 is a local conference dedicated to Java. It grew into a 1k+ developer’s meeting for southwest germany. You cannot avoid to meet former colleagues and chat non-stop in the pauses. The presentations are mostly very professional and worthwhile. We learnt a bit about long-term serialization issues (put a version in your XML namespace!), better JUnit (Rules are cool!), some Dependency Injection myths (though this presentation could have been snappier) and got introduced to Apache Hadoop (Map/Reduce at its best). Embedded Java still is the hell we remembered it to be. But the best presentation of the day clearly was Dr. Simon Wiest talking about Hudson and advanced techniques to speed up your build.

Retrospection of the brunch

The group of attendees was small again, with several firsttime guests. This helped the disgression factor a lot, we talked a lot about all kinds of topics that didn’t make it on the list above. The time and setup was a bit unusual, but the brunch itself was fun and insightful as always.

Non-trivial Custom Data in QActions

If you want to implement dynamic context menus with non-trivial custom data in your QActions, the Qt4 documentation is not very helpful. The article describes some solutions to this task.

Sometimes I get very frustrated with the online Qt4 documentation. Sure, the API docs are massive but for many parts they provide only very basic information. Unfortunately, many Qt books, too, often stop exactly at the point where it gets interesting.

One example for this are context menus. The API docs just show you how menus in general are created and how they are connected to the application: Basically, all menus are instances of QMenu which are filled with instances of QAction. QActions are used as representation of any kind of action than can be triggered from the GUI.

The standard method to connect QActions to the GUI controlling code is to use one of their signals, e.g. triggered(). This signal can be connected to a slot of your own class where you can then execute the corresponding action. This works fine as long as you have a limited set of actions that you all know at coding time. For example, a menu in your tool bar which contains actions Undo/Redo/Cut/Copy/Paste can be created very easily.

But there are use cases where you do not know in advance how many actions there will be in your menus. For example, in an application that provides a GUI for composing a complex data structure you may want to provide the user assisting context menus for adding new data parts depending on what parts already exist. Suddenly, you have to connect many actions to one slot and then you somehow have to know which QAction the user actually clicked.

Btw, let’s all recall the Command Pattern for a moment… ok, now on to some solutions.

Method 0 – QAction::setData: The QAction class provides method setData(), which can be used to store custom data in a QAction instance using QVariant as data wrapper. If you then use QMenu’s triggered signal, which gives you a pointer to the QAction that was clicked, you can extract your data from the QAction. I find this a little bit ugly since you have to wrap your data into QVariant which can get messy, if you want to provide more than one data element

Method 1 – Enhancing QAction::triggered(): By sub-classing QAction you can provide your own triggered() signal which you can enhance with all parameters you need in your slot.

class MyAction : public QAction
{
  Q_OBJECT
  public:
    MyAction(QString someActionInfo)
      : someActionInfo_(someActionInfo)
    {
      connect(this, SIGNAL(triggered()),
              this, SLOT(onTriggered()));
    }
  signals:
    void triggered(QString someActionInfo);
  private slots:
    void onTriggered() {
      emit triggered(someActionInfo_);
    }
  private:
    QString someActionInfo_;
};

This is nice and easy but limited to what data types can be transported via signal/slot parameters.

Method 2 – QSignalMapper: From the Qt4 docs on QSignalMapper:

This class collects a set of parameterless signals, and re-emits them with integer, string or widget parameters corresponding to the object that sent the signal.

… which is basically the same as we did in method 1.

Method 3 – Separate domain specific action classes: By the time the context menu is created you add QActions to the menu using QMenu’s addAction methods. Then you create instances of separate Command-like classes (as in Command Pattern) and connect them with the QAction’s triggered() signal:

// Command-like custom action class. No GUI related stuff here!
class MySpecialAction : public QObject
{
  Q_OBJECT
  public:
    MySpecialAction(QObject* parent, <all necessary parameters to execute>);

  public slots:
    void execute();
  ...
};

// create context menu
QAction* specialAction =
  menu->addAction("Special Action Nr. 1");
MySpecialAction* mySpecialAction =
  new MySpecialAction(specialAction, ...);
connect(specialAction, SIGNAL(triggered()),
        mySpecialAction, SLOT(execute()));

As you can see, QAction specialAction is parent of mySpecialAction, thereby taking ownership of mySpecialAction. This is my preferred approach because it is the most flexible in terms of what custom data can be stored in the command. Furthermore, the part that contains the execution code – MySpecialAction – has nothing at all to do with GUI stuff and can easily be used in other parts of the system, e.g. non-GUI system interfaces.

How have you solved this problem?

Are programming books overrated?

A little insight gathered through feedback from an internship. Software development books are somewhat overrated as they can’t teach practice well.

In the last few weeks, we had an internship of a student that just finished academic high school (“Gymnasium”) and is looking forward to take up studies in computer science. He wanted to get in touch with the practical aspects of the career he is about to choose. The programming courses in school merely covered the basics of a programming language (Java) and some UML.

We prepared the student for the internship by feeding him several books we thought were appropriate for his level of knowledge. The books were a beginner’s book about Java (Head First Java), an introduction to unit testing (Pragmatic Unit Testing) and a foundation on clean code programming (Refactoring). Our student read them thoroughly and could make references to the chapters during pair programming sessions.

Retrospective on the books

But one feedback we got from him was that the books alone were nearly useless for his case. If there wouldn’t have been tutorial style pair programming coding sessions and several short lectures , he couldn’t grasp the deeper meaning of the book chapters he read (he suffered from the “blank slate blockade” several times). This came a bit as a surprise for us, as the student was very clever and really into it. It wasn’t the student, it was the books.

But you can’t blame it on “Refactoring”, for example, as this book is an all-time classic filled with really important knowledge. It has to be the medium itself, books are not the ideal source to learn about programming and software development.

Books are part of the academics

There is an old question in our profession. It revolves around if we are more like engineers or artists, craftsmen or scientists. In the core of this question is a uncertainty about the right model of education. Artists and craftsmen prefer more practical training, with apprentice/master relations and personal knowledge transfer. For engineers and scientists, literature and more standardized lectures are better suited. Academic knowledge is transferred during debate, not during exercises.

The duality of our profession

Projecting the feedback of our student onto this question, there seems to be a duality in our profession: Both (or all four if you want) approaches are needed to form a whole. You can’t learn the theory and expect to excel on the job. But pratical experience alone will not suffice to keep up with the pace of our profession. Good books are like afterburners here, you’ll be hurled forward by every page.

Conclusion

If it’s really true that we need to learn our profession both ways at once, pair programming (in the tour guide or backseat driver style) is an essential part of our qualification. And our current university curriculum fails to deliver this part. Students nowadays can team up to program together on an assignment, but that’s not learning from a master (unless one in the team has distinctly more experience than everybody else and is able to transfer it). So I vote to bring more craftsmanship to the academic education, as the books alone won’t cut it.

Your opinion?

What’s your opinion on this topic? Drop us a line about your thoughts.

An Oracle story: Null, empty or what?

One big argument for relational databases is SQL which as a standard minimizes the effort needed to switch your app between different DBMSes. This comes particularily handy when using in-memory databases (like HSQL or H2) for development and a “big” one (like PostgreSQL, MySQL, DB2, MS SqlServer or Oracle) in production. The pity is that there are subtle differences with regard to the interpretation of the SQL-standard when it comes to databases from different vendors.

Oracle is particularily picky and offers quite some interesting behaviours: Most databases (all that I know well) treat null and empty as different values when it comes to strings. So it is perfectly valid to store an empty string in a not-null column and retrieving the string from the column yields an empty string. Not so with Oracle 10g! Inserting null and retrieving the value yields unsurprisingly null, even using Oracle. Inserting an empty string and retrieving the value leaves you with null, too! Oracle does not differentiate between empty strings and null values like a Java developer would expect. In our environment this has led to surprised developers and locally unreproducible bug which clearly exist in production a couple of times.

[rant]Oracle has great features for big installations and enterprises that can afford the support, maintenance and hardware of a serious Oracle DBMS installation. But IMHO it is a shame that such a big player in the market does not really care about the shortcomings of their flagship product and standards in general (Oracle 10g only supports SQL92 entry level!). Oracle, please fix such issues and help us developers to get rid of special casing for your database product![/rant]

The lesson to be learnt here is that you need a clone of the production database for your integration tests or acceptance tests to be really effective. Quite some bugs have slipped into production because of subtle differences in behaviour of our inhouse databases and the ones in production at the customer site.

Grails pitfall: Proxies and inheritance

When using inheritance in a lazy fetched association, proxies are a common pitfall in Grails.

Problem

You have a domain class hierarchy and want to use the classes in an association. You typically use the base class in a hasMany:

class Domain {
  static hasMany = [others:BaseClass]
}

Dependent on the actual class in the set others you want to call a different method:

public doSomething(domain) {
  domain.others.each {doThis(it)}
}

public doThis(ChildClassOne c) {}

public doThis(ChildClassTwo c) {}
...

Here the proxy mechanism of Hibernate (and Grails) causes a MethodMissingException to be thrown because the proxies are instances of the base class and not the actual child ones.
One way would be to activate eager fetching or you could use…

Solution: A dynamic visitor

Declare a visit method in the base class which takes a closure

def visit(Closure c) {
return c(this)
}

and make the dispatch in a method for the base class:

public doThis(BaseClass c) {
  return c.visit {doThis(it)}
}

Open Source Love Day June 2010

Our Open Source Love Day for June 2010 brought love for Hudson (especially the Campfire Plugin), Launch4j and RXTX. Everything went smooth and we were soaked with sweat due to massive sunshine.

Last wednesday, we held our Open Source Love Day for June 2010. This one was productive despite the heat that had us sweating the whole day long (as a sidenote: it got even warmer the days afterwards). Some features were finished and will help at least us in our projects. We still look forward for the right way to release them. Another release was even more problematic, you will read about it below.

The Open Source Love Day

We introduced a monthly Open Source Love Day (OSLD) to show our appreciation to the Open Source software ecosystem and to donate back. We heavily rely on Open Source software for our projects. We would be honored if you find our contributions useful. Check out our first OSLD blog posting for details on the event itself.

On this OSLD, we accomplished the following tasks:

  • Launch4j is a java application launcher for Windows, handling all the stuff a startup script would do, too. At the last OSLD, we added the ability to restart the application in case of a crash or other unplanned exit. To utilize this feature for automatic update routines, we needed to add the additional feature of starting another command instead of the original one. If the program fills a special file with the command needed, Launch4j will execute it after the program’s exit. This patch builds onto the previous patch and we are still investigating how to publish this functionality without breaking backward compatibility. We are looking forward to release it on the next OSLD.
  • We use RXTX to perform the serial (RS232) communication on all our java projects. We worked on an issue with serial converters over the course of several OSLDs now and released the patch to the issue tracker of RXTX after a longterm stability test. See the reworked patch for issue #144. There is another issue with the flush() method that seems to affect not only virtual RS232 ports that we currently investigate. But we aren’t yet able to come up with a complete issue description or a fix, so this will be suspended until the next OSLD.
  • We have written the Campfire Hudson Plugin as part of previous OSLDs. When issues emerged, we got patches from the community here. Thank you guys! We included the changes to the code and prepared a new release, when maven failed. This is not an issue, except when it fails repeatedly and messes up the workspace and the repository. After a long time of helpless fiddling with the parameters, we decided to start over and increase the version number to 2.1 (instead of 1.2). All of a sudden, everything worked out fine. Maven is a mysterious beast.
  • The initial work for a New Hudson Plugin was made. One tradition of the OSLD has always been to scratch our own itches. While there are many useful hudson plugins, we have the immediate need for another one that doesn’t exist yet. Without going into details here (we save this for the next OSLD), we produced a proof of concept and a first iteration of the code. Stay tuned for details on the next OSLD.

What were our lessons learnt today?

  • If you don’t succeed with maven’s automatic processes, do not try to sort out things manually. You’ll just end up with a gigantic mess that won’t work either way. The best way to deal with maven failures is to revert everything and try again with different parameters.
  • The best approach to develop hudson plugins is to adapt the old “monkey see, monkey do” process. There are so many plugins already, chances are good your immediate question was already answered somewhere. Just check the found solution for accidental complexity. Sometimes, the first solution isn’t the easiest.
  • When dealing with the legacy Win32 API, combined knowledge scraping is king. We had discussions throughout the day that only consisted of little parts of recollections about knowledge that seemed long forgotten. But finally, we put the pieces together and solved the problem. It should be called teamthink, i guess.

Retrospective on the OSLD

The weather at this OSLD was way too hot to operate at normal speed. But we got some nice results and a cliffhanger for the next OSLD. We left soaked with sweat but happy that evening.

Add flair to your code: Code Squiggles

Introduction to Code Squiggles, a coding style that improves the readability of your java code.

Wrought Iron by quadriremeFor several months now, I’m experimenting with a programming style that you might want to call “syntax aware programming”. Every coding step starts with the question “what do I want to achieve and how do I want to write it down?”. Then I proceed to write it down in this perfect manner, mostly some english sentence, and try to incrementally convert the syntax into something the java compiler stops complaining about. There’s a lot to be learnt about API design, naming and creative syntax usage this way. One thing I’ve discovered along the way are Code Squiggles.

Introduction to Code Squiggles

Code squiggles are little methods that contain no functionality, other than directly returning the single given parameter. Their purpose is to make the code more fluently readable by casual readers. Calling these methods is absolutely optional, as they offer no behaviour at runtime. But by bloating your code with these method calls, you lower the amount of syntax rules and conventions the reader has to know before being able to understand the code. The process of adding the method calls feels like adding “happy little squiggles” (I certainly miss Bob Ross!) to your code.

Adding Code Squiggles by example

Let me give you a full example how Code Squiggles can turn your boring old java code into something even non-programming readers can grasp without problems. Note that the process of transforming the code isn’t the process I initially described, but the way to deal with existing code.

The initial code fragment looks like this:

assertTrue(filesDirectory.getChild("0.png").isFile());

As you can see, it’s an assertion line of an unit test. We improve the readability by extracting the intent of the assertion into the called method name (it’s a normal “extract method” refactoring):

assertFileExists("0.png", filesDirectory);

Now is the time to add the first Code Squiggle:

assertFileExists("0.png", in(filesDirectory));

You’ve noticed the difference? It’s just the word “in”, but it improves the semantics of the second parameter. As I promised, Code Squiggles are methods without any functionality worth talking about:

protected VirtualFile in(VirtualFile filesDirectory) {
    return filesDirectory;
}

The method takes a parameter and returns it. The real “functionality” of this method lies within its name. Everything else is only necessary to overcome (or overcode) java’s shortcoming of advanced syntax definition measures.

That’s all about Code Squiggles. But it doesn’t stop here. Let’s improve the example to its final shape, when we add two squiggles:

assertFile(withName("0.png"), existsIn(filesDirectory));

Read this line out loud! And notice the subtle change in the assertion method’s name. It begins to deminish clarity without the Code Squiggles. That’s when your API begins to depend on them. But it’s still perfectly valid java code if you just omit them.

The conceptual origin of Code Squiggles clearly comes from the behaviour driven development (BDD) style of writing tests and the ScalaTest Matchers. So I can’t claim much originality or cleverness myself here. But Code Squiggles, despite this initial example, aren’t limited to test code.

Adding inline documentation with Code Squiggles

Remember the last time you needed to integrate an horrible third-party API? Probably, there was a method with seven or eight parameters and all of them were primitive ints. No matter how often you called this method, you couldn’t remember the order of these ints. That’s when Code Squiggles might help you a bit.

This is the signature of a fairly complex method:

protected int performCalculation(int value, int lowerLimit, int upperLimit, int offset) { ...

Therefore, your call isn’t very self-explanatory:

int result = performCalculation(10, 2, 23, 13);

But it might be a lot more understandable when you add some squiggles:

int result = performCalculation(value(10), lowerLimit(2), upperLimit(23), offset(13));

I won’t spell out the squiggle implementations, as they should be straight-forward. Note that the java compiler doesn’t catch up here. You can easily swap the squiggles around to obfuscate your code. All you got is read-time safety. If you want compile-time safety, you need to replace the primitives with types and probably pay for some rounds of beer for the third-party API developers to include your changes or write an adapter (“corruption layer” is my preferred term here).

Regular use of Code Squiggles

If you want to use squiggles a lot, you might think about collecting them in a dedicated class. Design them to be static and generic, and you can use them easily with static imports:

public static <T> T existsIn(T instance) {
    return instance;
}

But remember that there are reserved keywords in java that might hamper you a bit.

Conclusion

Code Squiggles are useless bloat to your code unless you value read-time safety or casual readability. They can tidy up your code to a point where method or even class names are affected to form a block of code where you only have to replace the funnier chars with blanks to obtain a paragraph of plain written english anybody can read and understand.

What are your ideas towards Code Squiggles? Have you used them on your code? Mind to share the result?

Code squiggles are little methods that contain no functionality, other than directly returning the single given parameter. Their purpose is to make the code more fluently readable by casual readers.