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Spring cache/fallback framework

My use case is that I want to cache certain request:response in my service caller classes:
public class Abc{
public Response serviceCall(Request r){}
}
public class Memcached{
public Response get(Request r){}
public void put(Request r, Response rs){}
}
I want to use memcached for caching . The request would be the key and value would be the response. Whenever serviceCall() is called I want to check if request is already present in cache if so then return response from the cache.
If not then actually execute serviceCall() method and put request:response key:value in memcached
Is there any way in spring to achieve the same.
I did look into #Cacheable here http://www.baeldung.com/spring-cache-tutorial
But I am unable to understand how I make spring use my "Memcached" class, more specifically where do I wire my "Memcached" class so that it is available to class "Abc" in above example
Could you please help . I am working in spring boot completely annotation based and looking for annotation based solution

Spring caching doesn't support Memcached by out-of-the-box (Supported Cache Providers).
If you want to use Memcached in your project please check out Memcached Spring Boot caching library.
There is also an example Java project of how to use Memcached with Spring.

You don't need the memcached class. Just put the #Cacheable annotation on Abc.serviceCall as per the baeldung tutorial.

developing a webservice using java and mysql

I am not familiar with websrvices and mysql ..i followed this http://www.vogella.com/articles/REST/article.html tutorial and developed a RESTful web service in Java with the JAX-RS reference implementation Jersey.
I want to create an websrevice using eclipse which select the data from mysql database and display the result in xml format.
I got lots of sample developing webservices with PHP and mysql but i want to develop in java.
Please suggest me some good tutorial/links on this or idea which may help me. i want to use that webservice in my android application.
In the above example ,i am not getting where to put the connection string to establish the connection between MySQL database and java files.
Here is the TodoResource.java :
package de.vogella.jersey.jaxb;
import javax.ws.rs.GET;
import javax.ws.rs.Path;
import javax.ws.rs.Produces;
import javax.ws.rs.core.MediaType;
import de.vogella.jersey.jaxb.model.Todo;
#Path("/todo")
public class TodoResource {
// This method is called if XMLis request
#GET
#Produces( { MediaType.APPLICATION_XML, MediaType.APPLICATION_JSON })
//#Produces( { MediaType.TEXT_XML })
public Todo getXML() {
Todo todo = new Todo();
todo.setSummary("This is my first todo");
todo.setDescription("This is my first todo");
todo.setMy_id(1);
return todo;
}
// This can be used to test the integration with the browser
#GET
#Produces( { MediaType.TEXT_XML })
public Todo getHTML() {
Todo todo = new Todo();
todo.setSummary("This is my first todo");
todo.setDescription("This is my first todo");
return todo;
}
}

I would start here : http://wiki.restlet.org/docs_2.1/13-restlet/21-restlet.html
You can create a java class/method that encapsulates the Business logic, for example a method like getData(DataFormat xml/html, whatData) which connects to the mysql database and retrieves records and then transforms it into required format, call this method within getXML() and getHTML()

Spring MVC makes REST based development very easy. Refer to this blog

The example you linked to does not actually make use of a database but uses in-memory Todo's to provide the data. In section 8 the author states
Create the following data model and a Singleton which serves as the
data provider for the model. We use the implementation based on an
enumeration.
The data model is the Todo class.
The data provider is the TodoDao enum. The purpose of TodoDao, is essentially to store Todo's in memory. In other words, it performs the function that would otherwise be done by a database.
What therefore needs to be done, is to:
Replace TodoDao with a database.
Map Todo to a table in the database.
To connect Java objects to a database, you can use an Object Relational Mapper (ORM), which can be achieved by using the Java Persistence API (JPA).
Therefore, to map Todo to a database table, it needs to be annotated with JPA annotations, thus creating a JPA Entity.
Have a look the accepted answer to REST/JSON Web Services Java EE Framework, it should shed some light on what needs to be done. Part 1 covers creating a database, while Part 2 covers creating and annotating JPA entities (Part 3 - JAXB Bindings for xml or json, Part 4 - The RESTFul Service, Part 5 - The Client).
If difficulties are still encountered, have a look at the answer I posted for Need to write a RESTful JSON service in Java, that should be suitable for someone who wants more nitty-gritty to, as a starting point, connect to a single table in a database and create a RESTful Web Service with JSON/XML representations using the following.
IDE: Eclipse IDE for Jave EE Developers (Kepler), comes with Maven built in
Database: MySQL (also makes use of MySQL Workbench)
Application Server: GlassFish 4.0
Java EE 7 (JAX-RS, JPA, JAXB, etc)
Any REST Client for testing: (eg Postman)

How to implement Soap Faults in Java webservices?

Am pretty new to web services and have been trying to implement Soap Faults. I used Apache Axis2 to generate webservice in the following manner.
public interface XYZ{
public String myMethod(User[] user)
}
Here I have created a User class with some variables so that I can generate User object at .Net environment to pass User[] of objects.
Public class Webservice implements XYZ
{
Public String myMethod(User[] user){
//My implementation
}
}
Now, I created a dynamic project using Eclipse and with the help of Axis2 plugin I created webservice for my "Webservice" class which generates wsdl file. I deployed the webcontent in the Tomcat folder and able to access the WSDL file in the .Net environment. I am able to pass array of objects (User[]) from .Net to Java and able to do my task. Now, I need to implement Soap Faults in Java which I am not sure how to implement.
Can anyone help me with an example or tutorial ?

Your best bet is to Google for something like "jax-ws faults". For example:
http://www.ibm.com/developerworks/webservices/library/ws-jaxws-faults/index.html
You can also implement an error handler, as discussed under "Using handlers in JAX-WS Web services" here:
http://axis.apache.org/axis2/java/core/docs/jaxws-guide.html#BottomUpService

Most frameworks will trigger a SOAP fault when you throw an Exception in the method implementing your operation. That will not give you much control on the SOAP fault content though.
See here for some details on Axis

Generally, You don't need any specific coding for implementing SOAP fault.. Whenever there is any exception thrown by the method (here myMethod in your example.), axis will automatically generate SOAPFault element in the resulting response. The exception is actually wrapped into AxisFault exception and sent to the client.
See here a i.

Creating a java server with rest

I need to create a rest server and client.
I stumbled upon this tutorial which uses sockets. I want to be able to use REST calls, possibly HTTP, because the clients will be actually in different languages.
Instead of using Socket api from java.net.* what should i use ? if i use Socket API can I use c++ and php to communicate with this server? or should i go with REST?
any directions appreciated.

There's a lot of things you can use to create rest services, and then they can be consumed by almost anything. Of particular awesomeness is the ability to hit them in your web browser, just because we're all so familiar with them.
When I need a 'quick and dirty' rest solution, I use Restlet - I won't claim it's the only solution, but it's the easiest I've ever worked with. I've literally said in a meeting "I could have XYZ up in 10 minutes." Someone else in the meeting called me on it, and sure enough, using Restlet I was able to get a functioning REST server running with the (very simple) features I said I would get in the meeting. It was pretty slick.
Here's a barebones server that has one method, returning the current time. Running the server and hitting 127.0.0.1:12345/sample/time will return the current time.
import org.restlet.Application;
import org.restlet.Component;
import org.restlet.Context;
import org.restlet.Restlet;
import org.restlet.data.Protocol;
import org.restlet.routing.Router;
/**
* This Application creates an HTTP server with a singple service
* that tells you the current time.
* #author corsiKa
*/
public class ServerMain extends Application {
/**
* The main method. If you don't know what a main method does, you
* probably are not advanced enough for the rest of this tutorial.
* #param args Command line args, completely ignored.
* #throws Exception when something goes wrong. Yes I'm being lazy here.
*/
public static void main(String...args) throws Exception {
// create the interface to the outside world
final Component component = new Component();
// tell the interface to listen to http:12345
component.getServers().add(Protocol.HTTP, 12345);
// create the application, giving it the component's context
// technically, its child context, which is a protected version of its context
ServerMain server = new ServerMain(component.getContext().createChildContext());
// attach the application to the interface
component.getDefaultHost().attach(server);
// go to town
component.start();
}
// just your everyday chaining constructor
public ServerMain(Context context) {
super(context);
}
/** add hooks to your services - this will get called by the component when
* it attaches the application to the component (I think... or somewhere in there
* it magically gets called... or something...)
*/
public Restlet createRoot() {
// create a router to route the incoming queries
Router router = new Router(getContext().createChildContext());
// attach your resource here
router.attach("/sample/time", CurrentTimeResource.class);
// return the router.
return router;
}
}
And here's the 'current time resource' that it uses:
import org.restlet.representation.Representation;
import org.restlet.representation.StringRepresentation;
import org.restlet.resource.Get;
import org.restlet.resource.ServerResource;
/**
* A resource that responds to a get request and returns a StringRepresentaiton
* of the current time in milliseconds from Epoch
* #author corsiKa
*/
public class CurrentTimeResource extends ServerResource {
#Get // add the get annotation so it knows this is for gets
// method is pretty self explanatory
public Representation getTime() {
long now = System.currentTimeMillis();
String nowstr = String.valueOf(now);
Representation result = new StringRepresentation(nowstr);
return result;
}
}

JAX-RS is the API for REST in Java. There are a lot of implementations, but the main ones are Jersey (the reference implementation), Apache's CXF and Restlet.

Usually, you don't create a server. You create a web application and deploy it on the server or servlet container. Some servlet containers are embedable into your web application, e.g. Jetty. Poppular free servlet containers are Tomcat, Glassfish, Jetty, etc.
For Restlet, it is not a servlet container. It is a framework that allow you to create a wep application with RESTful styles. So this should not be confused.
If you decide to use servlet container, then the problem is how you can create a web application with the RESTful styles. REST is not a technology - it is a design principle. It is a concept of how you should create the interface.
The design of REST is stateless so you do not need to store the state of the transaction. All information from a request should be sufficient to produce a respose to client.
There are several servlet framework that allows you to implment the REST styles easily. Some of them are very sophisticated, e.g. Spring framework.

Download JBoss 7. Problem solved.
Heres a restful service:
#Path("/myservice")
public class MyService {
#GET
#Produces(MediaTypes.TEXT_PLAIN)
public String echoMessage(#QueryParam("msg") String msg) {
return "Hello " + msg;
}
}
Create a WAR. Deploy. Open up browser and go http://myserver/myapp/myservice?msg=World. Done!

I would say go with an HTTP based RESTful service. It's rapidly becoming a defacto standard. Check my answer to this similar question for pros and cons.

This is the best one out there. Spring MVC which has lot of REST capabilities in itself. This takes just a single jar file to be included. And you are all set to use all it's capabilities. Even as simple as the below guy explained in JBOSS and much more flexibility as well.
http://java.dzone.com/articles/spring-30-rest-example

I use JBoss 6 with RestEasy. I have created a tutorial located here. I hope this helps you.

You're also welcome to see my very simple example for REST server implementation here.

How can annotations be added to dynamic proxy classes in Java?

I am trying to create a dynamic proxy that would wrap an EJB around a web service because the application server does not support creating an EJB based web service without a proprietary router project generation.
My thought was to create a dynamic proxy, and some how just start it using an InitServlet. Right now I am kind of stuck on figuring out how to set the annotations dynamically so that I won't get the following error.
class $Proxy0 has neither #WebSerivce nor #WebServiceProvider annotation
at com.sun.xml.internal.ws.server.EndpointFactory.verifyImplementorClass(EndpointFactory.java:277)
at com.sun.xml.internal.ws.transport.http.server.EndpointImpl.getPrimaryWsdl(EndpointImpl.java:273)
at com.sun.xml.internal.ws.transport.http.server.EndpointImpl.createEndpoint(EndpointImpl.java:213)
at com.sun.xml.internal.ws.transport.http.server.EndpointImpl.publish(EndpointImpl.java:143)

Recently I have had the same problem. It seems that most people say is not possible. See http://softwarecarnival.blogspot.be/2009/02/java-annotations-and-proxies.html
If the interface that you have is:
interface XXXInterface{
Result doStuff1(String param1)
}
then a workaround is to create a delegator to the proxy that will also implement the web service.
#WebService
public class WebServiceDelegateToXXXServer implements XXXInterface{
public WebServiceDelegateToXXXServer(XXXInterface actualImplementor){
this.actualImplementor = actualImplementor;
}
public Result doStuff1(String param1){
return actualImplementor.doStuff1(param1);
}
}
Then you will publish
XXXInterface proxy = createProxyAsXXXInterface();
Endpoint.publish(url, new WebServiceDelegateToXXXServer(proxy));