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How to start CloudFoundry app using ReactorCloudFoundryClient?

I used StartApplicationRequest to create a sample request to start the application as given below:
StartApplicationRequest request = StartApplicationRequest.builder()
.applicationId("test-app-name")
.build();
Then, I used the ReactorCloudFoundryClient to start the application as shown below:
cloudFoundryClient.applicationsV3().start(request);
But my test application test-app-name is not getting started. I'm using latest Java CF client version (v4.5.0 RELEASE), but not seeing a way around to start the application.
Quite surprisingly, the outdated version seems to be working with the below code:
cfstatus = cfClient.startApplication("test-app-name"); //start app
cfstatus = cfClient.stopApplication("test-app-name"); //stop app
cfstatus = cfClient.restartApplication("test-app-name"); //stop app
I want to do the same with latest CF client library, but I don't see any useful reference. I referred to test cases written at CloudFoundry official Github repo. I derived to the below code after checking out a lot of docs:
StartApplicationRequest request = StartApplicationRequest.builder()
.applicationId("test-app-name")
.build();
cloudFoundryClient.applicationsV3().start(request);
Note that cloudFoundryClient is ReactorCloudFoundryClient instance as the latest library doesn't support the client class used with outdated code. I would like to do all operations (start/stop/restart) with latest library. The above code isn't working.

A couple things here...
Using the reactor based client, your call to cloudFoundryClient.applicationsV3().start(request) returns a Mono<StartApplicationResponse>. That's not the actual response, it's the possibility of one. You need to do something to get the response. See here for more details.
If you would like similar behavior to the original cf-java-client, you can call .block() on the Mono<StartApplicationResponse> and it will wait and turn into a response.
Ex:
client.applicationsV3()
.start(StartApplicationRequest.builder()
.applicationId("test-app-name")
.build())
.block()
The second thing is that it's .applicationId not applicationName. You need to pass in an application guid, not the name. As it is, you're going to get a 404 saying the application doesn't exist. You can use the client to fetch the guid, or you can use CloudFoundryOperations instead (see #3).
The CloudFoundryOperations interface is a higher-level API. It's easier to use, in general, and supports things like starting an app based on the name instead of the guid.
Ex:
ops.applications()
.start(StartApplicationRequest.builder()
.name("test-app-name").build())
.block();

Java Google datastore async calls

I do not want to block threads in my application and so I am wondering are calls to the the Google Datastore async? For example the docs show something like this to retrieve an entity:
// Key employeeKey = ...;
LookupRequest request = LookupRequest.newBuilder().addKey(employeeKey).build();
LookupResponse response = datastore.lookup(request);
if (response.getMissingCount() == 1) {
throw new RuntimeException("entity not found");
}
Entity employee = response.getFound(0).getEntity();
This does not look like an async call to me, so it is possible to make aysnc calls to the database in Java? I noticed App engine has some libraries for async calls in its Java API, but I am not using appengine, I will be calling the datastore from my own instances. As well, if there is an async library can I test it on my local server (for example app engine's async library I could not find a way to set it up to use my local server for example I this library can't get my environment variables).

In your shoes, I'd give a try to Spotify's open-source Asynchronous Google Datastore Client -- I have not personally tried it, but it appears to meet all of your requirements, including being able to test on your local server. Please give it a try and let us all know how well it meets your needs, so we can all benefit and learn -- thanks!

Neo4j java rest binding

I am trying to get more familiar with the java-rest-binding (https://github.com/neo4j/java-rest-binding).
My main question is what operations of the GraphDatabaseService supports.
For example I read here that GlobalGraphOperation are not supported, but the tests use them. I have the final release (2.0.1). In adittion to this I would like to know if there is a significant defference between
GraphDatabaseService gds = new RestGraphDatabase("http://localhost:7474/db/data");
and
RestAPI restAPI = new RestAPIFacade("http://localhost:7474/db/data");`
or it's the same way to connect to the neo4j server.

The java-rest-binding is a flaky abstraction over REST-Operations over the wire. Unless you have a really good reason to use it, I wouldn't use it.
What's your actual use-case that you want to solve?

MATLAB proxy could not be created in 180000 milliseconds

I am using the matlabcontrol-4.0.0.jar library to call Matlab from Java. This on Ubuntu 11.10, Matlab r2011b and Java version "1.6.0_23".
When trying to run this simple program:
public static void main(String[] args) throws MatlabConnectionException,
MatlabInvocationException {
//Create a proxy, which we will use to control MATLAB
MatlabProxyFactory factory = new MatlabProxyFactory(options);
MatlabProxy proxy = factory.getProxy();
//Display 'hello world' just like when using the demo
proxy.eval("disp('hello world')");
//Disconnect the proxy from MATLAB
proxy.disconnect();
}
I get, after the Matlab launch screen appears (which is good), a time out:
Exception in thread "main" matlabcontrol.MatlabConnectionException:
MATLAB proxy could not be created in 180000 milliseconds at matlabcontrol.RemoteMatlabProxyFactory.getProxy(RemoteMatlabProxyFactory.java:158)
at
matlabcontrol.MatlabProxyFactory.getProxy(MatlabProxyFactory.java:81)
at Main.main(Main.java:15)
I've looked everywhere including all the tips from provided by stackoverflow, but nothing seems to fit the problem i am encountering
*UPDATE*
I forbore to mention that I already tried the scenario described by Joshua Kaplan (thanks!) .This seems be for my case of no help, meaning that it just keeps waiting. Could someone perhaps elaborate on the communication protocol between java and the matlab proxy?
-> It could be an incompatibility issue as well, I've posted on the website delivering the resource, have received no answer so far...
*END UPDATE*
So, any of you a tip where to start looking, that would be wonderful
thanks

The getProxy() method is a blocking operation with a default timeout of 3 minutes (or 180 seconds or 180000 milliseconds). For most people's machines that is long enough, if the connection was not established in that amount of time then something has gone wrong. However, this timeout can be changed by creating an instance of a MatlabProxyFactoryOptions which is done by using a MatlabProxyFactoryOptions.Builder. The MatlabProxyFactoryOptions instance you create is passed into MatlabProxyFactory's constructor. Here's an example with a 5 minute timeout:
MatlabProxyFactoryOptions options = new MatlabProxyFactoryOptions.Builder()
.setProxyTimeout(300000L)
.build();
MatlabProxyFactory factory = new MatlabProxyFactory(options);
MatlabProxy proxy = factory.getProxy();
Alternatively you can request a proxy which is a non-blocking operation that has no timeout. Once the proxy has been created it will be passed to the provided callback. Example:
MatlabProxyFactory factory = new MatlabProxyFactory();
factory.requestProxy(new MatlabProxyFactory.RequestCallback()
{
public void proxyCreated(MatlabProxy proxy)
{
//TODO: Make use of the proxy
}
});

I got similar problem. Main issue is that in your imported .jar file "matlabcontrol-4.0.0.jar" there is default, configuration in class Configuration.java. In my case there was problem, that libraries cannot properly call matlab with all arguments. Try to add to your project not .jar file, but package matalbcontrol with all source .java files. You can download it form the same page http://code.google.com/p/matlabcontrol/downloads/list, form where you got .jar libs. Then in Configuration.java edit getMatlabLocation() lines:
else if(isWindows() || isLinux())
{
matlabLoc = "matlab";
}
replace with:
else if(isLinux())
{
matlabLoc = "/usr/local/MATLAB/R2011b/bin/matlab"; //or place where you got installed your matlab, directory bin, in my case, like in example
}
else if(isWindows())
{
matlabLoc = "matlab";
}

Error implementing the Thrift API

I'm implementing the Thrift Remote Procedure call framework in Java. I set up thrift and generated my skeleton code without a lot of issues, but now that I'm actually using the API methods, I get strange errors.
Here are the errors I get:
Exception in thread "main" org.apache.thrift.transport.TTransportException: Cannot write to null outputStream
at org.apache.thrift.transport.TIOStreamTransport.write(TIOStreamTransport.java:142)
at org.apache.thrift.protocol.TBinaryProtocol.writeI32(TBinaryProtocol.java:163)
at org.apache.thrift.protocol.TBinaryProtocol.writeMessageBegin(TBinaryProtocol.java:91)
at SimonSays$Client.send_registerClient(SimonSays.java:102)
at SimonSays$Client.registerClient(SimonSays.java:96)
at simon.main(testClass.java:16)
I don't think I'm not making any mistakes, but just to make sure, here's the code that's leading to the errors:
TProtocol prot = new TBinaryProtocol(new TSocket("http://thriftpuzzle.facebook.com",9030));
SimonSays.Client client = new SimonSays.Client(prot);
client.registerClient("userEmailAddress#gmail.com");
The error is said to be generated from the client.registerClient() call, but that is a call to the code generated by Thrift, which makes me feel that I'm doing something wrong in setting up the connection itself.
The part about making a TProtocol instance I included myself, and it's likely that that's where the problem lies.
I was hoping that someone would have more of an idea about what's going wrong that I do.
Please let me know if more information or clarification is needed.
Edit: I found the TProtocol instantiation statement from the Cassandra Wiki

You need to call the open() method on your TSocket instance in order for it to connect and obtain the input/output streams it needs.
Source: TSocket.java