JSF: Automatically replace Tags in Strings with CommandLinks - jsf-2.2

Question

i have a String like "Hello [everyone]!". "Everyone" should be replaced with a commandLink that points to an Page-Object.
For Example:
My Code detects "[everyone]" and creates a new "Page" with the headline "everyone" in my JavaDB Database. Now i want that [everyone] will shown as an commandLink:
Hello <h:commandLink value="everyone" action="#{PageController.getPage(everyone)}" />
or something else.
ATM i have this code to display the text with the []-Tags:
<h:outputText value="#{PageController.currentPage.latestContent.text}" />
Now what is the best practise to replace Tags (i.e. [XYZ]) with a specific commandLink? Or rather: how i can replace substrings with JSF-Tags (they should be rendered)? I have only found the possibility to create converter, but only examples to convert the complete string. :/ To find out the right substring i use Regulary Expressions.
Merry Christmas :)

Answer 1

My Soluion:
#ApplicationScoped
#Named("TagViewPhase")
public class TagViewPhase implements Serializable {
Application app;
public void beforePhase(PhaseEvent event) {
if (app == null) {
app = event.getFacesContext().getApplication();
}
if (event.getPhaseId() == PhaseId.RENDER_RESPONSE) {
scanForPageContent(event.getFacesContext().getViewRoot());
}
}
private void scanForPageContent(UIComponent component) {
for (UIComponent i : component.getChildren()) {
if ("pageContent".equals(i.getId())) {
HtmlOutputText content = (HtmlOutputText) i;
HtmlPanelGroup group = generatePageContent(content);
content.getParent().getChildren().add(group);
content.getParent().getChildren().remove(i);
} else {
scanForPageContent(i);
}
}
}
private HtmlPanelGroup generatePageContent(final HtmlOutputText pContent) {
List<UIComponent> childTree = new ArrayList<>();
String content = pContent.getValue().toString();
Pattern pattern = Pattern.compile("\\[(.*?)\\]");
Matcher matcher = pattern.matcher(content);
Integer start, end = 0;
String linkValue;
while (matcher.find()) {
start = matcher.start();
if (end < start) {
HtmlOutputText htmlText = (HtmlOutputText) app.createComponent(HtmlOutputText.COMPONENT_TYPE);
htmlText.setValue(content.substring(end, start));
childTree.add(htmlText);
}
end = matcher.end();
linkValue = content.substring(start + 1, end - 1);
HtmlCommandLink link = (HtmlCommandLink) app.createComponent(HtmlCommandLink.COMPONENT_TYPE);
link.setValue(linkValue);
link.setActionExpression(JSFExpression.createMethodExpression(
"#{PageController.switchPageByString('" + linkValue + "')}",
String.class,
new Class<?>[]{}
));
childTree.add(link);
}
if (end < content.length()) {
HtmlOutputText htmlText = (HtmlOutputText) app.createComponent(HtmlOutputText.COMPONENT_TYPE);
htmlText.setValue(content.substring(end, content.length()));
childTree.add(htmlText);
}
HtmlPanelGroup group = (HtmlPanelGroup) app.createComponent(HtmlPanelGroup.COMPONENT_TYPE);
group.getChildren().addAll(childTree);
return group;
}
}
xhtml File:
<f:view beforePhase="#{TagViewPhase.beforePhase}">
<h:panelGroup>
<h:outputText id="pageContent" value="#{PageController.currentPageContent.text}" />
</h:panelGroup>
</f:view>