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How to get a Hazelcast map inside a Camel route?

I'm really fresh to Camel (and hazelcast, at that), and I've been playing around with it a bit recently. A seemingly simple operation is causing me a lot of trouble, and I'm struggling to find any waypointers anywhere.
I have a listener watching for changes on a hazelcast map. If said changes match a certain criteria, I want to grab the entire map and send it to a processor. Something like this:
from(hazelcast:map:someMap?hazelcastInstance=#hazelcastInstance)
.filter().method(SomeFilter.class, filterMethod)
.???
// If the filter cafeterias are met, get the entire map and send it to a processor
But I am really not sure how to, well, get entire map itself, especially using Java DSL. The closest thing I've found is to get the map's keySet and then call getAll(keySet) on it, which seems needlessly contrived for such a simple thing? If this is really the preferred method, there is another issue - how do you pass said keySet as the parameter to the getAll operation? I.e.:
<snip>
.setHeader(HazelcastConstants.OPERATION, constant(HazelcastConstants.GET_KEYS_OPERATION))
.to(hazelcast:map:someMap?hazelcastInstance=#hazelcastInstance) // Gets the keySet just fine.
.setHeader(HazelcastConstants.OPERATION, constants(HazelcastConstants.GET_ALL_OPERATION))
.????
// I've tried .setHeader(HazelcastConstants.OPERATION_PARAM, new
// SimpleExpression("${body}")> here,
// amongst many other things, but, I just get an empty object back, so it's
// pretty clear I'm messing up
// the format or parameter choice here.
.to(hazelcast:map:someMap?hazelcastInstance=#hazelcastInstance)
Using camel 2.18.0 here, by the way.

Well after bit more trial and error, I got it working. I swear it was one of the first things I tried, but I must've bungled it up on the first attempt and got stumped. All you really do is get the keySet and then put into OBJECT_ID. So something like this:
.setHeader(HazelcastConstants.OPERATION, constant(HazelcastConstants.GET_KEYS_OPERATION))
.to(hazelcast:map:someMap?hazelcastInstance=#hazelcastInstance)
.setHeader(HazelcastConstants.OPERATION, constants(HazelcastConstants.GET_ALL_OPERATION))
.setHeader(HazelcastConstants.OBJECT_ID, new SimpleExpression("${body}"))
.to(hazelcast:map:someMap?hazelcastInstance=#hazelcastInstance)
(Note: it's hazelcast-map in newer versions.)
And ta-dah, you've got a Hashmap to work with. The alternative seems to use QUERY, but I couldn't figure out the proper syntax for, well, the query. I'd love to hear if anyone has a working example with a QUERY header...

How to handle filtering in restlet resource

Hi i am pretty new to Restlet, and generally building web servers. I need to support filtering like this:
http://deviceip:port/resource?id=id
So far i know how to return a json message when user invokes different resources, based on my web server state. I would attach it to router, and add class which handles that resource. But how can i return only one resource from collection based on id? What i need to change in my class which is responsible from handling of that resource. Also how can i attach this resource to router? Any help is welcome, if you can write some code snippet to help me, that would be great.
Thanks

So as i understand you can approach to this in two ways. One is explained by link above and another one is using query. So basically you font have to create another resource like in the answer from link above, instead you can just extract query with this.getQuery()
and than call method getFirstValue("id"), which will return entered id.

Xamarin c# Loader example?

This problem is for Xamarin Android C# , but if someone can help in java I'm sure I can convert the code over ..
I'm trying to get some sort of automatic notification on a db that data has been inserted / deleted / etc.
There is outside apps that have access to the db in question, that insert / etc..
I've tried a file observer but it misses most of the inserts.
I've tried using content observer but it never fires a onchange
I've tried using the content observer inside a cursor but no onchange happens either.
(if I understand correctly they will only fire if I register a change occurred which is what I don't want)
Now I've discovered that loaders might be a solution..
They seem to have their own observer that fires when the data changes.
If this is also not an answer then perhaps a database trigger of some kind to notify my app the data was modified ?
I really need guidance here.. no idea how to properly implement a loader..
or if the content observer can be sufficient somehow with some sort of auto trigger as such..

OK, So!
The reason that file Observer was missing db inserts is because a SQLite DB is actually a 2 - 3 file object .. if you watch "Example.DB" then you can miss insert that can happen on Example.DB-shm or Example.DB-wal..
The fix to this, and its not a great fix, is to instead watch the folder ..
doing this will catch all inserts/deletes ..
The problem with this is that it will cause multiple OnChange() 's to execute..
So when coding a file observer like this, you have to either call the stopwatch() while you process the call and switch it on afterwards
OR
Have a "Global Variable" (C# guys are gonna swear at me for calling it that)
or static var
that lets the app know that you are already busy on the event so don't execute the code till the previous call has been completed ..

Is there any other alternative to template specific exclusion of pages from search

I have restricted some pages like admin pages from not getting visible in search results.Using the below code
map.put("group.1_group.1_property","**jcr:content/cq:template**");
map.put("group.1_group.1_property.1_value","**/apps/MyApp/templates/SampleTemplate**");
map.put("group.1_group.1_property.and","true");
map.put("group.1_group.1_property.operation","unequals");
final Query finalQuery = builder.createQuery(PredicateGroup.create(map),
session);
which means it is template specific search filtration,means that Im telling the query builder not to display those pages having the above specified template .However the drawback is that, in future if we want to restrict more pages, those pages also must be mapped to the above template. So instead of specifying the template in the map, can we put any other property in the map, so that search restriction is not template specific.
Thanks,
Balaji

What other properties do your pages have available (specifically, the admin pages)? For example, if you have a specific property that you add to your admin pages, or other pages that you could sort on, that could work. On one site I worked on, we had a property we put into certain content items called hideInNav. So along those lines, this is how I would do it:
map.put("group.1_group.1_property","jcr:content/hideInNav");
map.put("group.1_group.1_property.1_value","/content/somepath/you/want");
map.put("group.1_group.1_property.and","true");
map.put("group.1_group.1_property.operation","unequals");
I hope that helps to make sense of it. Am I understanding it correctly? If not, please clarify and I'll try to help more.
---------------EDIT-----------------------
If you don't have a custom property, but you know the path these pages are located, and maybe a default property they all have in common (like a jcr:title), you could try doing that instead. Like this:
map.put(1_group.0_path","/content/yoursite");
map.put(2_group.0_type","cq:Page");
map.put(3_group.fulltext","test text");
map.put(3_group.fulltext.relPath","jcr:content/#jcr:title");
You can see how this would run on a local query debugger when you have CQ running:
http://localhost:4502/libs/cq/search/content/querydebug.html?_charset_=UTF-8&query=http%3A%2F%2Flocalhost%3A4502%2Fcontent%2Fsalesportal%2Fen%2Fmobile%2Fresources.assets.get.json%3Fp.limit%3D7%0D%0A1_group.0_path%3D%2Fcontent%2Fyoursite%0D%0A2_group.0_type%3Dcq%3APage%0D%0A3_group.fulltext%3Dtest+text%0D%0A3_group.fulltext.relPath%3Djcr%3Acontent%2F%40jcr%3Atitle
Hopefully that's more helpful.
EDIT #2
This is a summary of both my answers, and will hopefully answer your last comment as well.
In order to more fully answer your question (since you're still not quite getting what you want), I dug a little deeper to find the information you need. Just as a reference, any time you're doing XPath querying, this is a great tool to look at: JCR Query Usecases - jboss
Anyway, you said that you were getting results that didn't include items that were missing the 'hideInNav' property. Here is how you can get those results, specifically:
map.put("1_group.0_path","/content/yoursite");
map.put("2_group.0_type","cq:Page");
map.put("3_group.1_property","jcr:content/hideInNav");
map.put("3_group.1_property.1_value","not");
map.put("3_group.1_property.operation","not");
This way, you're searching in the path you want, getting the type of result you want (cq:Page, if that is what you're actually looking for), and you're getting the results that DO NOT HAVE the property 'hideInNav'.

Understanding Android's webview addjavascriptinterface

I know that to interact from Javascript to Java you have to inject a Java object using the addjavascriptInterface method in webview.
Here is the problem I am facing.
I register a java object using addJavascriptInterface method to be available in my JS.
I inject few JS in the webview using webview.loadURL("javascript:XXX");
I send a JS event when I am done with injecting the JS.
The problem is that if immediately after step 1, if I execute the following Javascript:
mWebView.loadUrl("javascript:if(window.myobject) console.log('myobject found---------'); else {console.log('myobject not found----');}");
I get "myobject not found" in my console's log.
I want to know that if there is some time before I can access my object and if so, how do I get to know how much time should I wait to call my object?

I want to know that if there is some time before i can access my object
Yes, I think there is a delay, because WebView.addJavascriptInterface will run in the WebView's internal worker thread. Perhaps you've thought about this, and realized that WebView has to maintain at least one worker thread to do asynchronous network IO. Maybe you also noticed these threads in DDMS while using a WebView.
It turns out that it also uses a thread to do work for a number of other public methods. I really wish the docs from Google made this clearer! But I hope I can help and show you how I tried to confirm this for myself.
Follow me as I take a look at the source for WebView. It's reasonably readable, even if you can't follow exactly what's going on, it's possible to trace through answer some questions with respect to threads.
You can download the Android framework source through the SDK manager tool, but it's also mirrored on Github, so that's what I've linked to here. I guessed and picked a tag that's close to some version of ICS. It's not hard to find WebView.addJavascriptInterface. I just Googled "WebView.java site:github.com/android".
The method WebView.addJavascriptInterface sends a message to an instance of WebViewCore:
mWebViewCore.sendMessage(EventHub.ADD_JS_INTERFACE, arg);
In WebViewCore.java there are a bunch of overloaded methods called sendMessage, but we don't really need to know which exactly is being called, since they do pretty much the same thing. There's even a nice comment to give us a hint that we're in the right place! All of them are delegating to an instance of EventHub which is some inner class. This method turns out to be synchronized, and is sending a message to an instance of Handler, which is a good indication that this is probably running in another thread, but for completeness sake, let's find out!
That Handler is instantiated in EventHub.transferMessages which is called from WebViewCore.initialize. There are a few more hops here, but eventually I found out that this is called from run in WebCoreThread (subclass of Runnable), which is instantiated along with a new Thread right here.
What an adventure! So, even though I really can't say for sure what's going on with all these moving parts, I am pretty confident to say that this method is not synchronous, and sends a message to the WebView's worker thread. I hope that makes sense!
if so, how do i get to know how much time should i wait to call my object?
Unfortunately, I don't know the answer to this. I was researching this exact issue and found this question on StackOverflow in the course of my Googling. I think you have the following options, some of which are nicer or easier than others:
1) Just Thread.sleep for 100 ms or something between addJavascriptInterface and loadUrl("javascript:..."). Blech, I don't like this, but it is potentially the easiest.
2) Another possibility is that you could call WebView.loadUrl with a snippet of JavaScript that specifically tests if the interface is set, and catches the ReferenceError that is thrown if it's not set yet. However, as you might have guessed, this kind of involves adding a JavaScript interface to the WebView!
3) Call WebView.setWebChromeClient instead, and catch JavaScript's alert() or console.log instead. From my experiments, this method is synchronous, so there is no delay. (I have confirmed this in source, but I'll leave details as an exercise for the reader) You should probably come up with some special string to call alert with and check for it inside onJsAlert, so you aren't just catching all alert()s.
Sorry for the length of this answer, I hope that helps. Good luck!

Ensure your Javascript objects declared in your HTML / Javascript that you need to access from Java are declared global otherwise they will most likely be collected. I have code that does this (where Android is my interface added with addJavascriptInterface):
<script>
var cb = function(location) {
alert('location is ' + location);
}
Android.getLocation('cb');
</script>
The getLocation method invokes Android's LocationManager.requestSingleUpdate which then invokes the callback when the LocationListener fires.
Without the "var" I find that by the time the location lookup invokes the callback the callback function has been garbage collected.

(copied from my response on a similar question)
I've taken Jason Shah's and Mr S's implementation as the building block for my fix and improved upon it greatly.
There's just far too much code to put into this comment I'll just link to it.
Details: http://twigstechtips.blogspot.com/2013/09/android-webviewaddjavascriptinterface.html
Source: https://github.com/twig/twigstechtips-snippets/blob/master/GingerbreadJSFixExample.java
Key points are:
Applies to all versions of Gingerbread (2.3.x)
Calls from JS to Android are now synchronous
No longer have to map out interface methods manually
Fixed possibility of string separators breaking code
Much easier to change JS signature and interface names