Develop Reference

Add Renderer to Vaadin Grid

I migrating a Vaadin 8 project to Vaadin 14 and i try to show HTML in a grid column.
I figured out, that i have to use a TemplateRenderer, but how can i use it?
Here is the code from Vaadin 8:
grid.addColumn(e -> {
return ((Data) e).getValues()[index];
}).setCaption(myCaption).setRenderer(new HtmlRenderer());
In Vaadin 14 i did this:
gird.addColumn(e -> {
return TemplateRenderer.<Data>of((String) e.getValues()[index])
}).setHeader(myCaption);
e.getValues()[index] includes HTML, for example: <FONT SIZE = 4 COLOR = BLACK> ⚫</FONT>
In Vaadin 14 it always returns com.vaadin.flow.data.renderer.

Before we get to how to use a TemplateRenderer with Grid, I first need to point out that what you're trying to do is potentially dangerous because of the way it can lead to XSS vulnerabilities if the HTML strings that you want to show may be supplied by application users.
Using the Html component is indeed one potential solution to this problem, but it causes some overhead because there will be one component instance in memory for each row in the grid. There's also the same problem with potentially causing XSS vulnerabilities.
The first thing to notice with TemplateRenderer is that the renderer needs to be supplied directly as a parameter to addColumn. Wrapping it in a lambda will instead use that lambda as a value provider, which means that the toString() value of the renderer instance will be used with the default plain text renderer.
All rows should use the same renderer instance, configured with the same template string. The trick is that you can pass the data to show as a per-row property that the template will render for you. The last piece of the puzzle is that the template syntax tries to protect you against accidental XSS vulnerabilities, so you need to use a slightly contrived syntax to actually make it render the data as HTML.
Putting everything together, and also using JSoup to remove any dangerous stuff from your HTML strings, the working solution looks like this:
grid.addColumn(TemplateRenderer
.<Data> of("<div inner-h-t-m-l='[[item.html]]'></div>")
.withProperty("html", e -> {
String unsafeHtml = e.getValues()[index];
String safeHtml = Jsoup.clean(unsafeHtml, Whitelist.basic());
return safeHtml;
})).setHeader(myCaption);

I found a solution.
Instead of using the TemplateRenderer I used a ComponentRenderer.
The migration documentation recomented to use a TempleteRenderer or an ComponentRenderer instead of the htmlRenderer.
https://vaadin.com/docs/v14/flow/migration/8-migration-example.html#step-4-product-grid
Here is the code that worked for me:
grid.addColumn(new ComponentRenderer<>(e -> {
String value = (String) e.getValues()[index];
return new Html(value);
})).setHeader(String.valueOf(col + 1));

Comparing your attempts with TemplateRenderer and the documentation, I would assume it will have to look like this:
grid.addColumn(e ->
TemplateRenderer.<Data>of("[[item.customValue]]")
.withProperty("customValue", (String) e.getValues()[index])
).setHeader(myCaption);

How can I get value after hashtag from URL in Java

I have a URL and I want to print in my graphical user interface the ID value after the hashtag.
For example, we have www.site.com/index.php#hello and I want to print hello value on a label in my GUI.
How can I do this using Java in Netbeans?

Simple solution is getRef() in URL class:
URL url = new URL("http://www.anyhost.com/index.php#hello");
jLabel.setText(url.getRef());
EDIT: According to #Henry comment:
I would recommend to use the java.net.URI as it also deals with encoding. The Javadocs say: "Note, the URI class does perform escaping of its component fields in certain circumstances. The recommended way to manage the encoding and decoding of URLs is to use URI, and to convert between these two classes using toURI() and URI.toURL()."
and this comment:
Why not just doing uri.getFragment()
URI uri = new URI("http://www.anyhost.com/index.php#hello");
jLabel.setText(uri.getFragment());

Use the String.split() Method.
public static String getId(string url) {
return url.split("#")[1];
}
String.split() returns an array of Strings that are delimited, or "Split," by the value you pass to it, or in this case #.
Because you want only the string after the #, you can just use the second item in the array that it returns by adding [1] to the end of it.
For more on String.split() go to Tutorials Point.
By the way, the part of the URL you are referencing is the Element ID. It is used to jump to an Element on a webpage.

Build DB connection string from environment variables

I'm using the Play Framework (Java) and am not able to figure out how to use environment variables in my configuration file for building the database connection string. While I'm able to use environment variables like this (for user name and password):
default.username = ${?FU_MAIN_DB_USERNAME}
default.password = ${?FU_MAIN_DB_PASSWORD}
I'm not able to make it work in the url string. Perhaps this is a simple case of string processing in Scala that I'm missing, but since I'm working in Java, I could use some help.
So far, I have tried the url string in the following formats and failed:
Tried to add a $ to variable name to perform interpolation:
default.url = "jdbc:postgresql://$${?FU_MAIN_DB_HOST}:$${?FU_MAIN_DB_PORT}/$${?FU_MAIN_DB_NAME}";
But this doesn't substitute. Rather, it picks the string as such.
default.url = "jdbc:postgresql://${?FU_MAIN_DB_HOST}:${?FU_MAIN_DB_PORT}/${?FU_MAIN_DB_NAME}";
This too inserts the '$' and all verbatim. Then I thought maybe something like PHP-style will work
default.url = "jdbc:postgresql://${${?FU_MAIN_DB_HOST}}:${${?FU_MAIN_DB_PORT}}/${${?FU_MAIN_DB_NAME}}";
But no.
I also tried doing stuff like "jdbc:postgresql://".concat(${?FU_MAIN_DB_HOST}) ... but this also inserts '.concat' verbatim.
Finally, I tried concatenation using the '+' operator, but I'm told (by my IDE) that symbols like +: etc. are not allowed in the application.conf file.
How then, in God's name, am I supposed to do that?!

The double quotes turn off interpolation. But you need to do that for the : and the //.
Try
default.url = "jdbc:postgresql://"${?FU_MAIN_DB_HOST}":"${?FU_MAIN_DB_PORT}/${?FU_MAIN_DB_NAME}
Maybe you are better off to set the whole thing in one big environment variable instead.

java regex matcher results != to notepad++ regex find result

I am trying to extract data out of a website access log as part of a java program. Every entry in the log has a url. I have successfully extracted the url out of each record.
Within the url, there is a parameter that I want to capture so that I can use it to query a database. Unfortunately, it doesn't seem that the web developers used any one standard to write the parameter's name.
The parameter is usually called "course_id", but I have also seen "courseId", "course%3DId", "course%253Did", etc. The format for the parameter name and value is usually course_id=_22222_1, where the number I want is between the "_" and "_1". (The value is always the same, even if the parameter name varies.)
So, my idea was to use the regex /^.*course_id[^_]*_(\d*)_1.*$/i to find and extract the number.
In java, my code is
java.util.regex.Pattern courseIDPattern = java.util.regex.Pattern.compile(".*course[^i]*id[^_]*_(\\d*)_1.*", java.util.regex.Pattern.CASE_INSENSITIVE);
java.util.regex.Matcher courseIDMatcher = courseIDPattern.matcher(_url);
_courseID = "";
if(courseIDMatcher.matches())
{
_courseID = retrieveCourseID(courseIDMatcher.group(1));
return;
}
This works for a lot of the records. However, some records do not record the course_id, even though the parameter is in the url. One such example is the record:
/webapps/contentDetail?course_id=_223629_1&content_id=_3641164_1&rich_content_level=RICH&language=en_US&v=1&ver=4.1.2
However, I used notepad++ to do a regex replace on this (in fact, every) url using the regex above, and the url was successfully replaced by the course ID, implying that the regex is not incorrect.
Am I doing something wrong in the java code, or is the java matcher broken?

How to inject HTML into {0} of springMessageText in Velocity?

I'm using Apache Velocity in an internationalized Spring MVC website.
I want to use "Redirecting in X seconds" as the phrase (message key) that my translators will translate. The X will obviously be a variable number of seconds, and Javascript will update the page every second to count it down.
I thought I'd do this:
#springMessageText("Redirecting in {0} seconds" ["<span class='seconds'>5</span>"])
But this displays:
Redirecting in <span class='seconds'>5</span> seconds
(without parsing the HTML).
I need to be able to put the HTML tag in there because that is how javascript will know which part of the translated phrase to update.
What am I doing wrong?

UPDATED ANSWER:
I created a custom macro file called custom.vm:
#macro( springMessageHtml $code, $args, $defaultValue)
$springMacroRequestContext.getMessage($code, $args.toArray(), $defaultValue, false)
#end
In my velocity.properties file, I changed this line to reference it:
velocimacro.library=org/springframework/web/servlet/view/velocity/spring.vm,/velocity/custom.vm
And now in my views (like sample.vm), I can call it like:
#springMessageHtml("Redirecting in {0} seconds" ["<span class='seconds'>5</span>"])
OLDER ANSWER:
I found an answer here: http://feima2011.wordpress.com/2011/01/18/misc-notes/
#set($args = ["<span class='seconds'>5</span>"])
$springMacroRequestContext.getMessage("Redirecting in {0} seconds",
$args.toArray(), "", false)
#springMessageText is just a macro that calls $springMacroRequestContext.getMessage() anyway; by calling it directly, I'm able to specify that last parameter (a boolean for whether to escape the HTML).
Now I'm able to have unescaped HTML. Maybe eventually I'll code a new macro called #springMessageHtml, and it will call $springMacroRequestContext.getMessage() with the escapeHtml parameter set to False. Then in my view, I'd only need 1 line of code.