Am trying out the JMS example bundled with Apache Camel
ApplicationContext context = new ClassPathXmlApplicationContext("camel-config.xml");
producer)
ProducerTemplate camelTemplate = context.getBean("camelTemplate", ProducerTemplate.class);
System.out.println("Invoking the multiply with 22");
int responseData = (Integer)camelTemplate.sendBody("jms:queue:numbers", ExchangePattern.InOut, 22);
System.out.println("... the result is: " + responseData);
This is the code. This works perfectly when I run in as a standalone application.
The same thing I just put in a servlet and tried running it. I got this error
The OUT message was not received within
This was really a Blunder I made.
Thought of deleting the question. But many might do the same mistake
camelTemplate.sendBody("jms:queue:numbers", ExchangePattern.InOut, 22);
The problem was with the above line. Am passing 22 as parameter which is an Integer, but the real method in the JSM was receiving a InputStream as argument.
When I changed it , the problem got resolved.
Related
Requisite disclaimer about being new to Camel--and, frankly, new to developing generally. I'd like to have a string generated as the output of some function be the source of my camel route which then gets written to some file. It's the first part that seems challenging: I have a string, how do I turn it into a message? I can't write it into a file nor can I use JMS. I feel like it should be easy and obvious, but I'm having a hard time finding a simple guide to help.
Some pseudo-code using the Java DSL:
def DesiredString() {return "MyString";}
// A camel route to be implemented elsewhere; I want something like:
class MyRoute() extends RouteBuilder {
source(DesiredString())
.to("file://C:/out/?fileName=MyFileFromString.txt");
}
I vaguely understand using the bean component, but I'm not sure that solves the problem: I can execute my method that generates the string, but how do I turn that into a message? The "vague" is doing a lot of work there: I could be missing something there.
Thanks!
Not sure if I understand your problem. There is a bit of confusion about what the String should be become: the route source or the message body.
However, I guess that you want to write the String returned by your method into a File through a Camel route.
If this is correct, I have to clarify first the route source. A Camel Route normally starts with
from(component:address)
So if you want to receive requests from remote via HTTP it could be
from("http4:localhost:8080")
This creates an HTTP server that listens on port 8080 for messages.
In your case I don't know if the method that returns the String is in the same application as the Camel route. If it is, you can use the Direct component for "method-like" calls in the same process.
from(direct:input)
.to("file:...");
input is a name you can freely choose. You can then route messages to this route from another Camel route or with a ProducerTemplate
ProducerTemplate template = camelContext.createProducerTemplate();
template.sendBody("direct:input", "This is my string");
The sendBody method takes the endpoint where to send the message and the message body. But there are much more variants of sendBody with different signatures depending on what you want to send it (headers etc).
If you want to dive into Camel get a copy of Camel in Action 2nd edition. It contains everything you need to know about Camel.
Example:Sending String(as a body content)to store in file using camel Java DSL:
CamelContext context = new DefaultCamelContext();
context.addRoutes(new RouteBuilder() {
public void configure() {
from("timer:StringSentToFile?period=2000")
.setBody(simple(DesiredString()))
.to("file:file://C:/out/?fileName=MyFileFromString.txt&noop=true")
.log("completed route");
}
});
ProducerTemplate template = context.createProducerTemplate();
context.start();
I am working on a piece of code that uses CXF (3.1.2)
I am seeing this error intermittently:
java.lang.IllegalStateException: Entity is not available
at org.apache.cxf.jaxrs.impl.ResponseImpl.checkEntityIsClosed(ResponseImpl.java:481)
at org.apache.cxf.jaxrs.impl.ResponseImpl.doReadEntity(ResponseImpl.java:333)
at org.apache.cxf.jaxrs.impl.ResponseImpl.readEntity(ResponseImpl.java:320)
at org.apache.cxf.jaxrs.impl.ResponseImpl.readEntity(ResponseImpl.java:310)
To improve performance, the Response objects are held through a Google Guava LoadingCache (com.google.common.cache.LoadingCache). It seems like I would get this error after an object has been in the cache for a few minutes. Could the Response object because invalid
after a few minutes?
private static LoadingCache<String, Response> cachedLdapRespMap
= CacheBuilder.newBuilder()
.maximumSize(Constants.LDAP_RESP_CACHE_SIZE)
.expireAfterWrite(Constants.LDAP_RESP_CACHE_KEEP_ALIVE_MINUTE
, TimeUnit.MINUTES)
.build(
new CacheLoader<String, Response>() {
#Override
public Response load(String uid)
throws Exception {
Response res = makeLdapRequest(uid);
return res;
}
}
);
(I am answer the question myself)
The problem was that I have concurrent processes that attempted to readEntity(), the first process consumed the input stream (or may have even closed the stream), and the second process would either get thrown an IllegalStateException or got an empty message. Here is what the JavaDoc of javax.ws.rs.core.Response (which org.apache.cxf.jaxrs.impl.ResponseImpl extends) says:
Throws:
IllegalStateException - if the entity is not backed by an
input stream, the response has been closed already, or if the entity
input stream has been fully consumed already and has not been buffered
prior consuming.
So to fix the problem, I changed my design to cache not the Response object but rather the string message that is the result of the readEntity() call. The call would be done exactly once when the response comes back:
Response resp ...
String respStr = resp.readEntity(String.class);
and the problem is solved.
I got the following error:
This is my code:
At first glance, I see one problem: You never tell the SolrServer which core or collection to address. As is stated in the SolrJ docs:
There are two ways to use an HttpSolrClient:
1) Pass a URL to the constructor that points directly at a particular core
SolrClient client = new HttpSolrClient("http://my-solr-server:8983/solr/core1");
In this case, you can query the given core directly, but you cannot query any other cores or issue CoreAdmin requests with this client.
2) Pass the base URL of the node to the constructor
SolrClient client = new HttpSolrClient("http://my-solr-server:8983/solr");
QueryResponse resp = client.query("core1", new SolrQuery("*:*"));
BTW: You should use that Solrclient object that you commented out. The SolrServer objects are deprecated.
I have a problem using "fire()" with a GWT RequestFactory after I've used it to unfreeze and edit a proxy.
If I have two request factory objects and their associated contexts like this:
private SyntheticRequest req1 = requestFactory.someRequest();
private Request<xProxy> sendRequest1 = req1.something();
private SyntheticRequest req2 = requestFactory.someRequest();
private Request<xProxy> sendRequest2 = req2.something();
using "fire()" on the first request works fine:
sendRequest1.fire(new Receiver<xProxy>() {
#Override
public void onSuccess(xProxy response) {
...
if (somethingIsTrue){
xProxy x = req2.edit(response); //<-- **I think this causes a problem later, although the proxy "x" works as expected here.**
x.setSomething("something");
update();
}
});
that part runs ok because I get to the "onSuccess". But when this one runs "update()", which looks like this:
private void update(){
sendRequest2.fire(new Receiver<xProxy>(){
...onFailure...
...onSuccess...
});
}
sendRequest2 always fails, with the error
Server Error Index:0 Size:0
and I put a breakpoint in the code for the "something()" service and it never even gets to that code! There must be something about the "req2.edit()" that hurts req2 and sendRequest2, but what?
Thanks.
what is 'b'? the line xProxy x = req2.edit(b); is the first time it's mentioned? is it supposed to be xProxy x = req2.edit(response);
Anyway.. that is not the problem..
'Server Error' indicates that RequestFactory caught an exception during the processing of a request, server-side. Something (but maybe not something()) is throwing an IndexOutOfBounds exception.
If you have a look at RequestFactoryServlet.java (which you can replace with your own very easily btw) you can see it setting up a try catch block that catches all exceptions when processing a request. It passes them to 'DefaultExceptionHandler' which wraps them in a ServerFailure, and that gets returned to you GWT code as an onFailure() call.
An easy way to find where the exception is being thrown is set a breakpoint on IndexOutOfBoundsException, making sure to catch 'caught' exceptions as well as uncaught.
Sporadically, I receive an error in my WP7 Silverlight application. The error is a random "System.NotSupportedException". This error is thrown occassionally when the following code is executed:
// 1. Build the url
string serviceURL = "http://www.mydomain.com/service.svc/param1/param2";
// 2. Asynchronously execute the query using HttpWebRequest instead of WebClient. There is a UI performance issue with the WebClient currently
WebRequest request = HttpWebRequest.Create(serviceUrl);
request.BeginGetResponse(new AsyncCallback(MyService_Completed), request);
...
private void MyService_Completed(IAsyncResult result)
{
// Do stuff
}
I have verified that the URL I am sending is correct. Please note, that this request is part of my view model, which may have other network requests fired off at the same time. I have no idea why this happens ocassionally. Can anybody point out any potential reasons?
Thank you!
When this happens, make sure you look at the View Detail part of the exception report. It might be that your service is refusing connection or the data passed is invalid. NotSupported is a very general exception that covers many possible situations.
A similar question has been asked previously. If you look at the comments the original poster added to the answer, he claims to have solved the problem by replacing
request.BeginGetResponse(new AsyncCallback(MyService_Completed), request);
with
request.BeginGetResponse( MyService_Completed, request);