I don&#39;t think I can point to only one resource but I would take a path (which you can customize based on your level of understanding of REST). I&#39;m somebody who would like to get my concepts real clear first and then think about the tools to implement the concepts.

- If you haven&#39;t read [chapter 5 of Roy Fielding&#39;s dissertation][1], I&#39;d start from there. It&#39;s an excellent piece of writing, and what better source to learn from than the master himself.

-  Infoq is an excellent source for REST articles, helped me significantly, here is a [compilation of REST resources][2]. Also on Infoq read this [excellent article][3] by Allamaraju.

- If you are looking at books, the two that I liked so far: [RESTful Web Services Cookbook][4] and [RESTful Web Services][5] 

- As you are looking for Java-based services -- I&#39;d get familiar with [Jersey][6] and/or [RESTEasy][7]. Write as many small programs as you can, what&#39;s the best way to get familiarized.

-  When you are at a point to try an exciting RESTful framework that&#39;s based on Hypermedia constraint I&#39;d explore [Restfulie][8].

Obviously, I haven&#39;t provided a single resource, but something in the lines I&#39;ve provided would serve well, IMO.


  [1]: http://www.ics.uci.edu/~fielding/pubs/dissertation/rest_arch_style.htm
  [2]: http://www.infoq.com/minibooks/emag-03-2010-rest
  [3]: http://www.infoq.com/articles/subbu-allamaraju-rest
  [4]: http://www.amazon.com/RESTful-Web-Services-Cookbook-Scalability/dp/0596801688/ref=sr_1_3?ie=UTF8&amp;s=books&amp;qid=1273964210&amp;sr=1-3
  [5]: http://www.amazon.com/Restful-Web-Services-Leonard-Richardson/dp/0596529260/ref=pd_sim_b_1
  [6]: http://jersey.java.net/
  [7]: http://www.jboss.org/resteasy
  [8]: http://restfulie.caelum.com.br/

I found [REST in Practice][1] to be the best book covering different styles of REST architectures.  It&#39;s also far more practical in its advice than many other books (I wasn&#39;t impressed by RESTful Web Services as I think it lacks focus).

  [1]: http://www.amazon.com/REST-Practice-Hypermedia-Systems-Architecture/dp/0596805829

My recommendation would be this one:

[![alt text][1]][2]
&lt;!-- source: http://ecx.images-amazon.com/images/I/41gVyjIn3WL._BO2,204,203,200_PIsitb-sticker-arrow-click,TopRight,35,-76_AA300_SH20_OU01_.jpg --&gt;


  [1]: https://i.stack.imgur.com/H3KMa.jpg
  [2]: https://www.amazon.com/Restful-Web-Services-Leonard-Richardson/dp/0596529260

I&#39;d recommend this extensive [NetBeans tutorial][1], [this Sun tutorial][2] and maybe having at look at the [Restlet][3] framework.


  [1]: http://netbeans.org/kb/docs/websvc/rest.html
  [2]: http://java.sun.com/developer/technicalArticles/WebServices/restful/
  [3]: http://www.restlet.org/

I have used [RESTlet in Action][1] to learn about REST concepts. It&#39;s an early access book so only the first few chapters are currently available, but I found the writing to be very clear.


  [1]: http://www.restlet.org/documentation/books

Need some compact code for counting the number of lines in a string in Java. The string is to be separated by `\r` or `\n`. Each instance of those newline characters will be considered as a separate line. For example -

    &quot;Hello\nWorld\nThis\nIs\t&quot;
 
should return 4. The prototype is 

    private static int countLines(String str) {...}

Can someone provide a compact set of statements? I have a solution at here but it is too long, I think. Thank you.

Count the number of lines in a Java String

I want to be able to create a collection of functions in a header file that I could #include in one of my C Programs.

How can I create C header files

I&#39;m looking for a book or any other resource that will help me learn how to create RESTful APIs in Java. 
Looking on Amazon, I saw that there are [several solutions for RESTful Java][1], but I&#39;m looking for the one that is tailored to a novice.

Looking forward to getting your advices/opinions, thanks!


  [1]: http://www.amazon.com/s?tag=ronin-20&amp;index=blended&amp;field-keywords=restful%20java

What&#39;s the best source for learning how to create RESTful APIs in Java?

<p>I'm looking for a book or any other resource that will help me learn how to create RESTful APIs in Java.
Looking on Amazon, I saw that there are <a href="http://www.amazon.com/s?tag=ronin-20&#x26;index=blended&#x26;field-keywords=restful%20java" target="_blank" rel="noopener noreferrer">several solutions for RESTful Java</a>, but I'm looking for the one that is tailored to a novice.</p>
<p>Looking forward to getting your advices/opinions, thanks!</p>


May I know what is the difference between:-

 1. Spring
 2. Struts
 3. Struts 2
 4. Hibernate
 5. JavaServer Faces
 6. JavaServer Pages
 7. Tapestry

Are these technologies/framework complementary to each other? Or they are alternatives to each other (after I use one of them, then I don&#39;t need to use the other)?

Thanks.


What is the difference between Spring, Struts, Hibernate, JavaServer Faces, Tapestry?

I&#39;ve heard this term used, but I&#39;m not entirely sure what it means, so:

* What DOES it mean and what DOESN&#39;T it mean?
* What are some examples of what IS and ISN&#39;T microbenchmarking?
* What are the dangers of microbenchmarking and how do you avoid it?
   * (or is it a good thing?)

What is microbenchmarking?

I have the following code:

    String[] where;
    where.append(ContactsContract.Contacts.HAS_PHONE_NUMBER + &quot;=1&quot;);
    where.append(ContactsContract.Contacts.IN_VISIBLE_GROUP + &quot;=1&quot;);

Those two appends are not compiling. How would that work correctly?


How to add new elements to an array?

I have an HttpResponse object for a web request I just made. The response is in the JSON format, so I need to parse it.  I can do it in an absurdly complex way, but it seems like there must be a better way.

Is this really the best I can do?

        HttpResponse response; // some response object
        Reader in = new BufferedReader(
            new InputStreamReader(response.getEntity().getContent(), &quot;UTF-8&quot;));
        StringBuilder builder= new StringBuilder();
        char[] buf = new char[1000];
        int l = 0;
        while (l &gt;= 0) {
            builder.append(buf, 0, l);
            l = in.read(buf);
        }
        JSONTokener tokener = new JSONTokener( builder.toString() );
        JSONArray finalResult = new JSONArray( tokener );

I&#39;m on Android if that makes any difference.

How do I parse JSON from a Java HTTPResponse?

This question is related to my question on [existing coroutine implementations in Java][1].  If, as I suspect, it turns out that there is no full implementation of coroutines currently available in Java, what would be required to implement them?

As I said in that question, I know about the following:

  1.  You can implement &quot;coroutines&quot; as threads/thread pools behind the scenes.
  2.  You can do tricksy things with JVM bytecode behind the scenes to make coroutines possible.
  3.  The so-called &quot;Da Vinci Machine&quot; JVM implementation has primitives that make coroutines doable without
      bytecode manipulation.
  4.  There are various JNI-based approaches to coroutines also possible.

I&#39;ll address each one&#39;s deficiencies in turn.

## Thread-based coroutines ##

This &quot;solution&quot; is pathological.  The whole point of coroutines is to *avoid* the overhead of threading, locking, kernel scheduling, etc.  Coroutines are supposed to be light and fast and to execute only in user space.  Implementing them in terms of full-tilt threads with tight restrictions gets rid of all the advantages.

## JVM bytecode manipulation ##

This solution is more practical, albeit a bit difficult to pull off.  This is roughly the same as jumping down into assembly language for coroutine libraries in C (which is how many of them work) with the advantage that you have only one architecture to worry about and get right.

It also ties you down to only running your code on fully-compliant JVM stacks (which means, for example, no Android) unless you can find a way to do the same thing on the non-compliant stack.  If you do find a way to do this, however, you have now doubled your system complexity and testing needs.

## The Da Vinci Machine ##

The Da Vinci Machine is cool for experimentation, but since it is not a standard JVM its features aren&#39;t going to be available everywhere.  Indeed I suspect most production environments would specifically forbid the use of the Da Vinci Machine.  Thus I could use this to make cool experiments but not for any code I expect to release to the real world.

This also has the added problem similar to the JVM bytecode manipulation solution above: won&#39;t work on alternative stacks (like Android&#39;s).

## JNI implementation ##

This solution renders the point of doing this in Java at all moot.  Each combination of CPU and operating system requires independent testing and each is a point of potentially frustrating subtle failure.  Alternatively, of course, I could tie myself down to one platform entirely but this, too, makes the point of doing things in Java entirely moot.

So...

Is there any way to implement coroutines in Java without using one of these four techniques?  Or will I be forced to use the one of those four that smells the least (JVM manipulation) instead?

----------

*Edited to add:*

Just to ensure that confusion is contained, this is a *related* question to [my other one][1], but not the same.  That one is looking for an **existing** implementation in a bid to avoid reinventing the wheel unnecessarily.  This one is a question relating to how one would go about implementing coroutines in Java should the other prove unanswerable.  The intent is to keep different questions on different threads.

  [1]: https://stackoverflow.com/questions/2846428/coroutines-in-java &quot;StackOverflow: Coroutines in Java&quot;

Implementing coroutines in Java

Is there a public API from some big company to get my public ip from within a program? 

I&#39;ve found `http://ip-address.domaintools.com/myip.xml`, which is exactly what I want, but unfortunately it blocks Python&#39;s `urllib` as well as many other http libraries, unless you spoof user-agent (anything doing that can&#39;t be called an API at all).

The problem is that I need this data for some potentially open source library, so we have to play by the rules. I also know that I can just do smth like `print $_SERVER[REMOTE_ADDR]`, but I don&#39;t want to server traffic to everyone using my library.

So, is there something like the URL above, but real API, that allows robots?

Getting my public IP via API

I&#39;m at the point where I need to write unit tests for a REST API written using CakePHP 1.3. The API supports GET, POST and PUT requests for querying and manipulating data.

Is there any established way to test the correct input/output of an API simulating an HTTP request, using **fixtures**? I do not want to run actual POST/PUT requests against the live (dev) database. How can I best mock out the system to use temporary models, yet test the rest of the stack as-is?

----------

Testing GET requests is easy enough with [controller tests][1]. However, for data manipulation the API uses HTTP headers quite extensively and also parses raw XML and JSON POST/PUT data. The controller unit test methods only mock POST data by setting `$this-&gt;data` in the controller, which does not allow me to properly test the API.

  [1]: http://book.cakephp.org/view/1210/Testing-controllers

How to unit test your API?

Now, I did find the [Google Finance API][1] and started looking through that but I found a lot of info about portfolios, transactions, positions &amp; other stuff I know nothing about. 

Am I looking at the wrong docs? What do I need to do to get a feed of exchange rates from GF? Is this even possible?

**EDIT**

To make things a little clearer. I&#39;m not interested in technical stuff nor do I want any code. 



  [1]: http://code.google.com/apis/finance/
  [2]: http://themoneyconverter.com/RSSFeeds.aspx

How do I get currency exchange rates via an API such as Google Finance?

Is there any podcast directory search API out there apart from the iTunes search API? I have looked around but could not find anything useful. Can I use feedburner for this? Is there a search API for feedburner too? 

Podcast search API

I selected API minimum level 1.5 for my android app and I&#39;m just about to integrate gestures in to it which came in 1.6. Is there a way in Eclipse to change the minimum level from 1.5 to 1.6 halfway through building an app?

Many thanks

Can you change min. API level for your Android app in Eclipse?

I&#39;m trying to inject a *Stateless EJB* into my JAX-RS webservice via annotations. Unfortunately  the EJB is just `null` and I get a `NullPointerException` when I try to use it.


    @Path(&quot;book&quot;)
    public class BookResource {
    
        @EJB
        private BookEJB bookEJB;
    
        public BookResource() {
        }
        
        @GET
        @Produces(&quot;application/xml&quot;)
        @Path(&quot;/{bookId}&quot;)
        public Book getBookById(@PathParam(&quot;bookId&quot;) Integer id)
        {
            return bookEJB.findById(id);
        }
    }

What am I doing wrong?

Here is some information about my machine:

 - Glassfish 3.1 
 - Netbeans 6.9 RC 2
 - Java EE 6

Can you guys show some working example? 

Inject an EJB into JAX-RS (RESTful service)

What is the proper way to structure a RESTful resource for resetting a password?

This resource is meant to be a password resetter for someone who has lost or forgotten their password.  It invalidates their old password and e-mails them a password.

The two options that I have are:

    POST /reset_password/{user_name}

or...

    POST /reset_password
       -Username passed through request body

I&#39;m pretty sure the request should be a POST.  I&#39;m less confident that I have selected an appropriate name.  And I&#39;m not sure if the user_name should be passed through the URL or the request body.

RESTful password reset

Hey, I&#39;m working on the model layer for our app here.

Some of the requirements are like this:

 1. It should work on iPhone OS 3.0+.
 2. The source of our data is a RESTful Rails application.
 3. We should cache the data locally using Core Data.
 4. The client code (our UI controllers) should have as little knowledge about any network stuff as possible and should query/update the model with the Core Data API.

I&#39;ve checked out the *WWDC10 Session 117* on Building a Server-driven User Experience, spent some time checking out the [Objective Resource](https://github.com/yfactorial/objectiveresource/tree/master), [Core Resource](http://coreresource.org), and [RestfulCoreData](http://github.com/lukeredpath/RestfulCoreData) frameworks. 

The Objective Resource framework doesn&#39;t talk to Core Data on its own and is merely a REST client implementation. The Core Resource and RestfulCoreData all assume you talk to Core Data in your code and they solve all the nuts and bolts in the background on the model layer.

All looks okay so far and initially I though either Core Resource or RestfulCoreData will cover all of the above requirements, but... There&#39;s a couple of things none of them seemingly happen to solve correctly:

1. The main thread should not be blocked while saving local updates to the server.
2. If the saving operation fails the error should be propagated to the UI and no changes should be saved to the local Core Data storage.

Core Resource happens to issue all of its requests to the server when you call `- (BOOL)save:(NSError **)error` on your Managed Object Context and therefore is able to provide a correct NSError instance of the underlying requests to the server fail somehow. But it blocks the calling thread until the save operation finishes. FAIL.

RestfulCoreData keeps your `-save:` calls intact and doesn&#39;t introduce any additional waiting time for the client thread. It merely watches out for the `NSManagedObjectContextDidSaveNotification` and then issues the corresponding requests to the server in the notification handler. But this way the `-save:` call always completes successfully (well, given Core Data is okay with the saved changes) and the client code that actually called it has no way to know the save might have failed to propagate to the server because of some `404` or `421` or whatever server-side error occurred. And even more, the local storage becomes to have the data updated, but the server never knows about the changes. FAIL.

So, I&#39;m looking for a possible solution / common practices in dealing with all these problems:

1. I don&#39;t want the calling thread to block on each `-save:` call while the network requests happen.
2. I want to somehow get notifications in the UI that some sync operation went wrong.
3. I want the actual Core Data save fail as well if the server requests fail.

Any ideas?




How to sync CoreData and a REST web service asynchronously and the same time properly propagate any REST errors into the UI

I&#39;m in need of some clarification. I&#39;ve been reading about REST, and building RESTful applications. According to wikipedia, REST itself is defined to be *Representational State Transfer*. I therefore don&#39;t understand all this stateless *gobbledeygook* that everyone keeps spewing.

From wikipedia:

&gt; At any particular time, a client can either be in transition between
&gt; application states or &quot;at rest&quot;. A client in a rest state is able to
&gt; interact with its user, but creates no load and consumes no per-client
&gt; storage on the set of servers or on the network.

Are they just saying don&#39;t use session/application level data store??? 

I get that one goal of REST is to make URI access consistent and available, for instance, instead of hiding paging requests inside posts, making the page number of a request a part of the GET URI.  Makes sense to me. But it seems like it is just going overboard saying that *no per client data* (session data) should ever be stored server side.

What if I had a queue of messages, and my user wanted to read the messages, but as he read them, wanted to block certain senders messages coming through for the duration of his session? Wouldn&#39;t it make sense to store this in a place on the server side, and have the server only send messages (or message ID&#39;s) that were not blocked by the user?

Do I really have to send the entire list of message senders to block each time I request the new message list? The message list pertinent to me wouldn&#39;t/shouldn&#39;t even be a publicly available resource in the first place.. 

Again, just trying to understand this. Someone *please* clarify. 


----------


**Update:**

I have found a stack overflow question that has an answer that doesn&#39;t quite get me all the way there:
https://stackoverflow.com/questions/2641901/how-to-manage-state-in-rest
which says that the client state that is important *should* all be transferred on every request.... Ugg.. seems like a lot of overhead... Is this right??



If REST applications are supposed to be stateless, how do you manage sessions?

I&#39;m looking to make a service which I can use to make calls to a web-based REST API.

Basically I want to start a service on app init then I want to be able to ask that service to request a url and return the results.  In the meantime I want to be able to display a progress window or something similar.

I&#39;ve created a service currently which uses IDL, I&#39;ve read somewhere that you only really need this for cross app communication, so think these needs stripping out but unsure how to do callbacks without it.  Also when I hit the `post(Config.getURL(&quot;login&quot;), values)` the app seems to pause for a while (seems weird - thought the idea behind a service was that it runs on a different thread!)

Currently I have a service with post and get http methods inside, a couple of AIDL files (for two way communication), a ServiceManager which deals with starting, stopping, binding etc to the service and I&#39;m dynamically creating a Handler with specific code for the callbacks as needed.

I don&#39;t want anyone to give me a complete code base to work on, but some pointers would be greatly appreciated.

Code in (mostly) full:

    public class RestfulAPIService extends Service  {
    
    final RemoteCallbackList&lt;IRemoteServiceCallback&gt; mCallbacks = new RemoteCallbackList&lt;IRemoteServiceCallback&gt;();

    public void onStart(Intent intent, int startId) {
        super.onStart(intent, startId);
    }
    public IBinder onBind(Intent intent) {
        return binder;
    }
    public void onCreate() {
        super.onCreate();
    }
    public void onDestroy() {
        super.onDestroy();
        mCallbacks.kill();
    }
    private final IRestfulService.Stub binder = new IRestfulService.Stub() {
        public void doLogin(String username, String password) {
            
            Message msg = new Message();
            Bundle data = new Bundle();
            HashMap&lt;String, String&gt; values = new HashMap&lt;String, String&gt;();
            values.put(&quot;username&quot;, username);
            values.put(&quot;password&quot;, password);
            String result = post(Config.getURL(&quot;login&quot;), values);
            data.putString(&quot;response&quot;, result);
            msg.setData(data);
            msg.what = Config.ACTION_LOGIN;
            mHandler.sendMessage(msg);
        }

        public void registerCallback(IRemoteServiceCallback cb) {
            if (cb != null)
                mCallbacks.register(cb);
        }
    };

    private final Handler mHandler = new Handler() {
        public void handleMessage(Message msg) {

            // Broadcast to all clients the new value.
            final int N = mCallbacks.beginBroadcast();
            for (int i = 0; i &lt; N; i++) {
                try {
                    switch (msg.what) {
                    case Config.ACTION_LOGIN:
                        mCallbacks.getBroadcastItem(i).userLogIn( msg.getData().getString(&quot;response&quot;));
                        break;
                    default:
                        super.handleMessage(msg);
                        return;

                    }
                } catch (RemoteException e) {
                }
            }
            mCallbacks.finishBroadcast();
        }
        public String post(String url, HashMap&lt;String, String&gt; namePairs) {...}
        public String get(String url) {...}
    };

A couple of AIDL files:

    package com.something.android
    
    oneway interface IRemoteServiceCallback {
        void userLogIn(String result);
    }

and 

    package com.something.android
    import com.something.android.IRemoteServiceCallback;

    interface IRestfulService {
        void doLogin(in String username, in String password);
        void registerCallback(IRemoteServiceCallback cb);
    }

and the service manager:


    public class ServiceManager {

        final RemoteCallbackList&lt;IRemoteServiceCallback&gt; mCallbacks = new RemoteCallbackList&lt;IRemoteServiceCallback&gt;();
        public IRestfulService restfulService;
        private RestfulServiceConnection conn;
        private boolean started = false;
        private Context context;

        public ServiceManager(Context context) {
            this.context = context;
        }
    
        public void startService() {
            if (started) {
                Toast.makeText(context, &quot;Service already started&quot;, Toast.LENGTH_SHORT).show();
            } else {
                Intent i = new Intent();
                i.setClassName(&quot;com.something.android&quot;, &quot;com.something.android.RestfulAPIService&quot;);
                context.startService(i);
                started = true;
            }
        }

        public void stopService() {
            if (!started) {
                Toast.makeText(context, &quot;Service not yet started&quot;, Toast.LENGTH_SHORT).show();
            } else {
                Intent i = new Intent();
                i.setClassName(&quot;com.something.android&quot;, &quot;com.something.android.RestfulAPIService&quot;);
                context.stopService(i);
                started = false;
            }
        }

        public void bindService() {
            if (conn == null) {
                conn = new RestfulServiceConnection();
                Intent i = new Intent();
                i.setClassName(&quot;com.something.android&quot;, &quot;com.something.android.RestfulAPIService&quot;);
                context.bindService(i, conn, Context.BIND_AUTO_CREATE);
            } else {
                Toast.makeText(context, &quot;Cannot bind - service already bound&quot;, Toast.LENGTH_SHORT).show();
            }
        }

        protected void destroy() {
            releaseService();
        }

        private void releaseService() {
            if (conn != null) {
                context.unbindService(conn);
                conn = null;
                Log.d(LOG_TAG, &quot;unbindService()&quot;);
            } else {
                Toast.makeText(context, &quot;Cannot unbind - service not bound&quot;, Toast.LENGTH_SHORT).show();
            }
        }

        class RestfulServiceConnection implements ServiceConnection {
            public void onServiceConnected(ComponentName className, IBinder boundService) {
                restfulService = IRestfulService.Stub.asInterface((IBinder) boundService);
                try {
                restfulService.registerCallback(mCallback);
                } catch (RemoteException e) {}
            }

            public void onServiceDisconnected(ComponentName className) {
                restfulService = null;
            }
        };

        private IRemoteServiceCallback mCallback = new IRemoteServiceCallback.Stub() {
            public void userLogIn(String result) throws RemoteException {
                mHandler.sendMessage(mHandler.obtainMessage(Config.ACTION_LOGIN, result));

            }
        };

        private Handler mHandler;

        public void setHandler(Handler handler) {
            mHandler = handler;
        }
    }


Service init and bind:

    // this I&#39;m calling on app onCreate
    servicemanager = new ServiceManager(this);
    servicemanager.startService();
    servicemanager.bindService();
    application = (ApplicationState)this.getApplication();
    application.setServiceManager(servicemanager);

service function call:

    // this lot i&#39;m calling as required - in this example for login
    progressDialog = new ProgressDialog(Login.this);
    progressDialog.setMessage(&quot;Logging you in...&quot;);
    progressDialog.show();

    application = (ApplicationState) getApplication();
    servicemanager = application.getServiceManager();
    servicemanager.setHandler(mHandler);

    try {
        servicemanager.restfulService.doLogin(args[0], args[1]);
    } catch (RemoteException e) {
        e.printStackTrace();
    }

    ...later in the same file...
                
    Handler mHandler = new Handler() {
        public void handleMessage(Message msg) {

            switch (msg.what) {
            case Config.ACTION_LOGIN:

                if (progressDialog.isShowing()) {
                    progressDialog.dismiss();
                }

                try {
                    ...process login results...
                    }
                } catch (JSONException e) {
                    Log.e(&quot;JSON&quot;, &quot;There was an error parsing the JSON&quot;, e);
                }
                break;
            default:
                super.handleMessage(msg);
            }

        }

    };


Content Type	Original Author	Original Content on Stackoverflow
Question	Marius Butuc	View Question on Stackoverflow
Solution 1 - Java	Surya Suravarapu	View Answer on Stackoverflow
Solution 2 - Java	Will Sargent	View Answer on Stackoverflow
Solution 3 - Java	Pascal Thivent	View Answer on Stackoverflow
Solution 4 - Java	Bozhidar Batsov	View Answer on Stackoverflow
Solution 5 - Java	dafmetal	View Answer on Stackoverflow

What's the best source for learning how to create RESTful APIs in Java?

Java Problem Overview

Java Solutions

Solution 1 - Java

Solution 2 - Java

Solution 3 - Java

Solution 4 - Java

Solution 5 - Java

How can I create C header files

Count the number of lines in a Java String

Attributions