There's a lot of information out there, but I can't quite figure out:
What's Java's answer to PHP's SoapClient()?
No frills, just want to create a client to access the methods described by a .wsdl document.
See this question. There are many Web Services frameworks in Java that can generate a client from a WSDL file. Eclipse has a plug-in to create a client stub from a WSDL file using the Axis2 framework. Perhaps this is the easiest option for a beginner.
If all you want is a piece of software to generate client code from an existing WSDL, you have more options than you can shake a stick at. I've tried several, and they all do pretty much the same thing in the same way, the big difference between them being the documentation. For me, the best documented of the lot is Apache CXF, which will generate JAX-WS-compliant code that you can then use with any JAX-WS library in your application (such as CXF itself, or Sun's JAX-WS-RI, and so on).
It's going to be more complex than SoapClient, I would imagine.
JAX-WS, most appserver vendors supply implementations and tooling.
See glassfish for an exmple implementation. The glassfish guide docs give details of how to go about developing, there are many variations depending upon how you would normally go about doing Java development. For me, I work with IBM tools and therefore simply load up RAD point as the WSDL and click "generate".
You can try using RCPServiceClient class in axis2.
Here is the java doc for it:
ws.apache.org/axis2/1_1_1/api/org/apache/axis2/rpc/client/RPCServiceClient.html
It doesn't require you to generate code to call web services.
Here is a decent example of how you can interact with a service using RPCServiceClient.
ws.apache.org/axis2/1_2/pojoguide.html#testingpojows
Do remember that java is strongly typed language so you can't do things like serviceClient->someRandomFunction(params), since someRandomFunction will not be defined ahead of time if you are trying to do something like PHP's SoapClient.
However, it will be equivalent to $soapClient->_soapCall function, as you will be able to do something like
serviceClient.invokeBlocking(
opProcess, -- function you are trying to call..
opResponseArgs, -- these are arguments you are passing
returnTypes); -- types that you are expecting back
Hope this helps.
Related
The circumstances force me to start writing a java based server and I am looking for a REST framework for Java. I really like the way OpenRasta works - a REST framework for .NET, so my question - does anyone know a REST framework for Java which works similarly to OpenRasta?
Thanks.
EDIT
Unfortunately, I am not in a position to be an early adaptor, so well established frameworks have preference over emerging ones.
You want to use one of the implementations of the JAX-RS specification, one of the main ones being Jersey. The specification and it's implementations have been around for a long time and are tried and tested (as opposed to Play! which you don't seem to like due to it being a newer framework).
I used OpenRasta and then worked on Java projects using JAX-RS. It will feel very familiar and you will get the benefits of POJOs like you get from OpenRasta's use of POCOs. I feel it's a great choice for creating RESTful services. In fact, I would probably chose it over OpenRasta now but this is more due the benefits of working within a Unix environment than the frameworks themselves.
The play framework is a popular new choice for Scala and the JVM:
http://www.playframework.org/documentation/1.2/routes
One option is Play!, which is basically framework based off Ruby on Rails.
Second option you might be interested in is Lift, which also has really cool features like comet, AJAXy snippets, etc. But it is a little bit different than Play!.
As part of this project, I would recommend Restlet which is the first and most comprehensive REST framework for Java. It works on both client and server side and is indeed resource centric, not just a MVC framework adapted to REST.
I am really really having hard time to create simple "Hello World" Web Service in Java. If you exclude several mobile Android mobile apps I have done, I am pretty new to Java environment.
First I tried Axis2 and that simply doesn't work out of the box. Fresh installation of Eclipse, Tomcat 6.0 and Axis2. Tried sample test app and it failed miserably. You can read about it here. My conclusion is that Axis2 simply doesn't work (maybe it used to work). I will try to go back to install older versions, maybe one will magically start working. I have to modify some old project at work that was using Axis2, so that's why I have to stick with it. I would hate to have to migrate to some other tool.
Then I ran on Oracle article Getting Started with JAX-RPC and I was thinking, cool, let's try that. Well, I just managed to get pissed off. After getting half way through the article and trying to write some simple test web service I realized that their code examples are poorly written. Missing brackets, wrong references, missing explanations, etc...
First of all, an interface should extend not implement. Am I right?
public interface SunRegPort implements java.rmi.Remote {
Also, this doesn't exist:
import java.xml.rpc.server.ServiceLifecycle;
But this does:
import javax.xml.rpc.server.ServiceLifecycle;
Well, I don't feel competent to criticize too much (cause of my level of knowledge about this subject of course), but after all I am suspicious that this article is complete JUNK and therefore I am not able to follow it.
Please somebody tell me that I am wrong and if anybody has some advice or link to some How-To page that talks about web services, I would appreciate.
Thanks.
The terminology Web Services is pretty vague. In Java, the modern and reasonably easy way to do this is by annotating classes.
I would recommend that first, you decide whether you want to implement:
SOAP Web Services -> look at JAX-WS
REST Web Services -> look at JAX-RS
Once you have chosen the "type" of Web Services, choose the library that implements the specification.
The Wikipedia entries list a few of these implementations. Apache CXF (complete but a beast), Jersey (popular) and Restlet are very common choices. I personally like the JBoss implementations as well for JAX-WS.
For JAX-WS with Apache CXF, here is a quick start tutorial that looks pretty good (untested)
For JAX-RS with Jersey, try this
Unless you have strong reasons to do otherwise (for instance you need to call an existing system), use REST which is simpler and leaner.
I would recommend you to check out the CXF project by apache. It's quite easy to use and should help you to set up a webservice.
There is a nice guide to Hello world set up.
http://cxf.apache.org/docs/a-simple-jax-ws-service.html
If you're still interested in giving Tomcat a shot, here is a tutorial on youtube of making a very basic "Hello world" example using Eclipse. It leaves a lot to learn; but it looks like it will at least get you started.
FYI, the version of Eclipse used is slightly outdated. So some of the menu options may not be exactly the same:
http://www.youtube.com/watch?v=EOkN5IPoJVs
Also, the meaning of "Web Service" can be subjective. So, to be specific; this just shows you how to get a basic HTTP endpoint started on your local machine.
If you are not tied to Eclipse, give NetBeans a shot. I think it's much better for Web Services in Java.
Web Services are most widely implemented examples of Service Oriented Architecture (SOA). A service contract is defined with the help of SOAP and Web Service Definition Language (WSDL) and that is published for other applications to use.
In this article we will see how we can create web service and web service client in java.
http://www.opencodez.com/java/how-to-build-and-deploy-web-service-and-client-in-java.htm
If I have implemented a Java Library (that offers certain functionality), could I transform this into a JavaScript library, such that the same functionality can be offered?
I know this may be an ask, but, I was wondering if there are frameworks existing that help in this?
No, in general this is not possible, Java and JavaScript are more or less completely different languages.
However there are a couple of Java to JavaScript translators that you can try. Java2Script is one such tool. Apparently the Google Web Toolkit (GWT) does this as well. Source.
While you could probably do some sort of conversion, it's important to note that Java and JavaScript, while similarly named, are not at all related. Unfortunately, I think you'll be hard pressed to find a framework or system that does a good job converting one to the other. :(
Everything I download seems hellbent on using all of Java EE. I need to build a single page to handle requests to it and do a tiny bit of processing based on parameters. This is to hook into another framework that will routinely call this URL.
I want a quick and easy way to create a page with some processing. Is there an easy way to do this using Java? I am using Java because I am comfortable with Java. I used SE for years and did some work in EE but I don't want all the stuff that comes with EE.
Should I maybe just avoid Java altogether and use something else. This needs to be deployed in a linux environment.
I used SE for years and did some work in EE but I don't want all the stuff that comes with EE.
Then just use a Servlet and that's all. Nothing, I repeat NOTHING, forces you to use "all that stuff" and your question is either a free rant or shows some deep misunderstanding.
You need Tomcat (or jetty, or any servlet container - jetty has an embeddable version btw)
You need a .jsp file and optionally an HttpServlet
Generally, it's not a good practice to put any processing code in a JSP, but if it is really simple and won't be extended, simply put the logic there - it is translated to a Servlet anyway.
yes, all the servlet based solutions are quite chubby.
jetty is all right, but the download is 20MB. that is ridiculous.
currently, the best choice is probably com.sun.net.httpserver which is bundled in JDK 6. you can easily implement your service.
It sounds like you could use PHP to do your processing. Call the page and POST the parameters to it, compute, and return the result.
If you are not very particular about using java and are willing to experiment, you should look at nodejs. It runs on V8 javascript engine and runs on linux.
There are a couple of fraemworks for nodejs for web apps:
Expressjs and spludo
as mentioned, you can do this very simply with jetty and a servlet, you don't even need a JSP if you just need a URL that does some processing based on request parameters and returns a response.
For development, it's really easy to create a dynamic web project in eclipse, just follow the steps in this article.
That said, I don't think java is a great choice for really lightweight stuff. PHP is probably the easiest thing to use if you just want to get it working yesterday.
You can use Java with FastCGI. This is very flexible, but also a bit low-level for most Java programmers.
If you aren't afraid of servlets (they are only a very small part of Java EE!), I can recommend JAX-RS, it is quite easy to get started with. If you client-side is JavaScript based, you can avoid using JSP (which I would recommend you to avoid).
For example, see backbone-jax-cellar. The Java source is here. For a Java app, this is light-weight. He is rolling his own DAO, but that's the price you pay for using Java and SQL and no dependencies (other than JDBC). The code is reminiscent of object-oriented PHP if you ask me. The point is, that if you have a JavaScript client, you don't need template rendering or all that cruft and a REST interface should be enough.
If you are afraid of the heavy build systems too, I made an example REST Todo app backend (which uses an existing frontend) that only requires a POSIX system, the JDK and sqlite3, and gets its own other dependencies (including webserver). I did not use a DAO. The repository front page has a README.
Another possibility is the Play Framework which does not use Java EE. It is rather heavy-weight, though. Full featured though. You would definitely need to use an IDE for this, you don't need that for developing JAX-RS/FastCGI apps.
I would reccomend Sinatra it is a very light-weight ruby web framework.
I need to implement webservices in an upcoming project and wanted to know what are the main points to base the decision on whether to implement using java or .NET
I'm a C++er...
If you're a Java shop use Java. If you're a .NET shop use .NET.
There really is no difference that makes one of the two languages superior to the other in regards to web services.
Possible consideration - .NET pre 3.5 only provided support for SOAP based services, but I believe the 3.5 WCF offers REST and SOAP now.
There's no real difference from programmer's point of view (implementation).
For me, a reason to pick Java is that all tools and infrastructure are free/open source. OS, deployment web server, databases, IDEs and developer tools.
I have plenty of experience with both, and both will certainly do the job.
However I tend to prefer Java over .Net for things like web services for the following reasons:
It's cross-platform, which gives you much better options on the hosting side (e.g. running a big Linux cluster on Amazon EC2)
The library ecosystem is larger and more mature, especially on the server side.
I prefer the more flexible open source philosophy to "the only way is Microsoft". Vendor lock-in is always a bad idea for your enterprise architecture in the long run.
You can optionally use awesome languages like Clojure or Scala on the JVM
Ultimately though, I'd go with the one your team has the most skills with. This will determine what you are most productive with, which is usually most important if your main objective is to deliver value quickly.
It's a personal decision, usually determined by the technology already in place or the skill set of the developer(s) writing the services.
i've never really developed web services in java, but i have in .NET and if you're using Visual Studio they're an absolute cinch to whip up (i expect they're a little more difficult to do without the aid of VS).
if you're already working in java, and don't have any .NET stuff in place, stick with java - it'll save you a lot of money (if you were to get Visual Studio in, as i mentioned), and possibly some time involved in learning the specifics of .NET
In my experience, Web Services are a bit more tightly integrated into Visual Studio than they are into Java's editors.
The Eclipse IDE doesn't even have JAX-WS (Java standard web services stack) support built in, opting to use Apache Axis 1 instead.
Netbeans supports JAX-WS, though.
I personally prefer .NET to Java for many reasons I don't want to go through, since it doesn't really matter and is more a personal preference than a strict guideline I can recommend.
If you have Java infrastructure in place or using a platform other than Windows for your server applications, I strongly suggest Java. However, if you don't have anything in place and running on Windows platform, .NET is pretty cool in that area (WCF/ASMX/WSE/...).
As you say you're a C++ - er you'll probably find .NET easier as you can target it directly from C++.
I'm a Java guy, but I think Web Services are easier to code in .NET. Visual Studio takes care of everything, in Java it takes a bit to get started.
A bit of a problem in some projects with JAX-WS is, that SUN ships the "old" version 2.0 with Java 6. If you want to use the current version, it's some work to make it run with Java 5 and Java 6.
If your app must be portable, you should obviously choose Java. Otherwise I would say it's just a choice of your preferred language, since the above issues are really small (maybe you want to choose Axis or something else anyway, I haven't worked with something other than JAX-WS yet).
IMO if you want to do SOAP, then its a heck of a lot easier to use .NET and WCF. However, I've found REST to be a bit tricky with WCF, and had to implement a custom XML parser to do it instead of using their built-in one.
You probably want to consider your hosting environment too. If you are going to serve this from Windows hardware, you can drop .NET WCF web services into IIS. If you are going to run a Linux/Solaris server, then it isn't even a question...
I suggest implementation with JSP ,it provides a robust platform for development
I prefer JSP to ASP or any microsoft techonolgy!