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Is there a way to set a validation and edit a long value in an editable Vaadin 8 Grid

I have a Vaadin 8 Grid where I would like to set one column as editable. For this I have where Food.calories is a long (yes in this case it could be an int but keep in mind this is an example and my specific use case requires a long):
Binder<Food> binder = foodGrid.getEditor().getBinder();
TextField caloriesTextField = new TextField();
binder.forField(caloriesTextField)
.withValidator(CustomCaloryValidator::isValidValue, "Must be valid a positive amount")
.withConverter(new StringToCaloriesConverter("Must be an integer"))
.bind(Food::getCalories, Food::setCalories);
// This line fails with the error because the types do not match.
foodGrid.addColumn(Food::getCalories, new NumberRenderer(myNumberFormat))
.setEditorComponent(new TextField(), Food::setCalories);
Unfortunately this doesn't work and has the following error:
Inferred type 'C' for type parameter 'C' is not within its bound; should implement 'com.vaadin.data.HasValue'
I looked everywhere I could and couldn't find any example of anything beyond simple edits. The demo sampler did have a more complex example using a slider but I couldn't figure out how to extrapolate from that example...
I understand the error, it's trying to map a long to a String. However I can't find a way to add a converter to the addColumn to make it work...

Firstly the main issue was that the Binder did not specify the generic type, it needed to be:
Binder<Food> binder = foodGrid.getEditor().getBinder();
And NOT:
Binder binder = foodGrid.getEditor().getBinder();
That being said there were several other gotchas. First when you do a forField() you need to keep track of that binding to be able to set it later with the column. This wasn't clear at all for me. Specifically you need to:
Binder.Binding<Food, Long> caloriesBinder = binder.forField(caloriesTextField)
.withValidator(CustomCaloryValidator::isValidValue, "Must be valid a positive amount")
.withConverter(new StringToCaloriesConverter("Must be an integer"))
.bind(Food::getCalories, Food::setCalories);
I'm not 100% sure on the caloriesBinder because my code is different and this is an example, but you need that binding. You then take that binding and do:
foodGrid.getColumn("calories").setEditorBinding(caloriesBinding);
This allows the correct editor to work. This is in the documentation but the example is very simple so I missed that.
The next step which is extremely important depending on what you're displaying, is to add a renderer otherwise you can run into some weird issues. For example if you're using long to store a currency then you need to convert it to display a currency amount. Similarly if you're using a date then you probably also want to format it. You then need to add a renderer. The only way I could find how to do it without compilation errors (mismatched types) was:
((Grid.Column<Food, Long>)foodGrid.getColumn("calories")).setRenderer(new CaloriesRenderer());
Just for completeness you then need to enable the editor with:
foodGrid.getEditor().setEnabled(true);
Lastly, if the table is part of a bigger bean then you need to call foodGrid.setItems(), you cannot just rely on binder.readBean() because it cannot accept a list. So for example if instead of food the bean was a meal which consisted of a number of ingredients, then you could not do binder.readBean(meal) nor could you do binder.readBean(meal.getIngredients) even though you can do binder.readBean(meal) for the rest of the form. The only way I could make it work was to do:
binder.readBean(meal);
foodGrid.setItems(meal.getIngredients);

fail to create a string with inner properties

I have a map prop call row which is Map (string , string), now what I want is to add to it a Link key val to the map, but from some reason I get fail when im trying to do s"=HYPERLINK(\"${tmpLink}\")", which suppose to work cause if s"=HYPERLINK(\"www.something.com\")") it works, so obviously there is something wrong with the ${tmpLink} but I dont understan why, you can see here how I set up tmpLink which I checked and is a string:
val tmpLink = s"https://bla.com/${invID.replaceAll("[\"=]", "")}"
row ++ Map("Link" -> s"=HYPERLINK(\"${tmpLink}\")")
and the error I get is:
value $ is not a member of (String, String)
someone knows whats the issue?

Here is issue you are facing https://issues.scala-lang.org/browse/SI-6476, essentially, escapes don't work with string interpolation.
It's unfortunate but for most cases you can use the triple quote syntax as a work around:
s"""=HYPERLINK("${tmpLink}")"""
And it will work.

convert from boolean to byte in java

I need to set byte value as method parameter. I have boolean variable isGenerated, that determines the logic to be executed within this method. But I can pass directly boolean as byte parameter this is not allowed and can't be cast in java. So the solution I have now looks like this:
myObj.setIsVisible(isGenerated ? (byte)1 : (byte)0);
But it seems odd for me. Maybe some better solution exists to do this?

your solution is correct.
if you like you may avoid one cast by doing it the following way:
myObj.setIsVisible((byte) (isGenerated ? 1 : 0 ));
additionally you should consider one of the following changes to your implementation:
change your method to something like setVisiblityState(byte state) if you need to consider more than 2 possible states
change your method to setIsVisible(boolean value) if your method does what it's looking like

You can use this solution. I found it on this very useful page
boolean vIn = true;
byte vOut = (byte)(vIn?1:0);

It is not odd. It is OK.
The odd is that you need to transform typed boolean value to not self explainable byte. However sometimes we have to do this when working with legacy APIs.
BTW if you want to save memory you can use 1 bit instead of byte, so you can group several boolean flags together while using bit for each boolean value. But this technique is relevant for huge amounts of data only when saving several bytes can be significant.

Accessing specific Grails Params in controller

This is probably a simple one and more Java related than grails but I'm a bit lost and not sure where to even start looking on this, I've googled about but am not really sure what I'm after, so would appreciate a pointer if possible please!
In the grails app I have a form which I save, all well and good. In the controller I can see the list of params it returns via a simple println and when I want to find a specific value currently I do a params.each and then compare the key to a pre defined string to find the one I want, my question is: -
Can I, and how would I, specifically say "get me the value of the parameter with the key "banana", rather than having to loop through the whole list to find it?
Also is there a way of creating a new set of secondary params, or just another plain old dictionary item (is that the right term?) where I use a regular expression to say "give me all the items whose key match the pattern "XYZ"?
It probably doesn't make much difference speed wise as the params are never that big but it'd be nice to make things more efficient where possible.
Any feedback much appreciated!

For a first question, to get 'banana' parameter you have to use:
params.banana
For second, find all with regexp:
def matched = params.findAll { it.key =~ /XYZ/ }
//or
Pattern p = ~/XYZ/
def matched = params.findAll { p.matcher(it.key).matches() }

There's a params object you can use. Eg with someurl.com?myparam=test you can access it with "params.myparam"
More information over here: http://grails.org/doc/2.2.x/ref/Controllers/params.html

using java for replacing text in database

i am using replace method for editing text in mysql database and its working well for
every time i try to replace a string by some other string e.g
REPLACE(Eligibility_Points , '(ii)', 'second point is')";
works well for above case
but does not work well in the following case
REPLACE(Eligibility_Points , '(ii)-(iii)', 'second and third point is')";
how should i fix this problem, thanks for your help

Assuming that this is the MySQL REPLACE string function you are talking about, the only reason I can see why the second example wouldn't work is that (maybe) the Eligibility_Points field (or whatever) doesn't contain the first string at all.
Maybe you could provide more context; e.g. what evidence you have that the replace isn't working.
However #vadchen makes a good point. If you do the replacement in the first example, then it will remove all examples that might trigger a replacement in the second example. Maybe you just need to do the "edits" in the reverse order.
There is no need to escape any of the characters in those fragments, either from the Java or SQL perspective.