Merge pull request #281 from ankurkaushal/master
Reformat according to google style guide
This commit is contained in:
@ -2,31 +2,33 @@ package com.iluwatar.servicelocator;
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/**
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*
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* The Service Locator pattern is a design pattern used in software development
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* to encapsulate the processes involved in obtaining a service with a strong
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* abstraction layer. This pattern uses a central registry known as the "service
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* locator", which on request returns the information necessary to perform a certain task.
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* The Service Locator pattern is a design pattern used in software development to encapsulate the
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* processes involved in obtaining a service with a strong abstraction layer. This pattern uses a
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* central registry known as the "service locator", which on request returns the information
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* necessary to perform a certain task.
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* <p>
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* In this example we use the Service locator pattern to lookup JNDI-services
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* and cache them for subsequent requests.
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* In this example we use the Service locator pattern to lookup JNDI-services and cache them for
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* subsequent requests.
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* <p>
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*
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* @author saifasif
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*
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*/
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public class App {
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/**
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* Program entry point
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* @param args command line args
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*/
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public static void main(String[] args) {
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Service service = ServiceLocator.getService("jndi/serviceA");
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service.execute();
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service = ServiceLocator.getService("jndi/serviceB");
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service.execute();
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service = ServiceLocator.getService("jndi/serviceA");
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service.execute();
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service = ServiceLocator.getService("jndi/serviceA");
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service.execute();
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}
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/**
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* Program entry point
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*
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* @param args command line args
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*/
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public static void main(String[] args) {
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Service service = ServiceLocator.getService("jndi/serviceA");
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service.execute();
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service = ServiceLocator.getService("jndi/serviceB");
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service.execute();
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service = ServiceLocator.getService("jndi/serviceA");
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service.execute();
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service = ServiceLocator.getService("jndi/serviceA");
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service.execute();
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}
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}
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@ -1,29 +1,29 @@
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package com.iluwatar.servicelocator;
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/**
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* For JNDI lookup of services from the web.xml. Will match name of the service name that
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* is being requested and return a newly created service object with the name
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* For JNDI lookup of services from the web.xml. Will match name of the service name that is being
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* requested and return a newly created service object with the name
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*
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* @author saifasif
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*/
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public class InitContext {
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/**
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* Perform the lookup based on the service name. The returned object will need to be
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* casted into a {@link Service}
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*
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* @param serviceName a string
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* @return an {@link Object}
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*/
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public Object lookup(String serviceName) {
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if (serviceName.equals("jndi/serviceA")) {
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System.out.println("Looking up service A and creating new service for A");
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return new ServiceImpl("jndi/serviceA");
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} else if (serviceName.equals("jndi/serviceB")) {
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System.out.println("Looking up service B and creating new service for B");
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return new ServiceImpl("jndi/serviceB");
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} else {
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return null;
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}
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/**
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* Perform the lookup based on the service name. The returned object will need to be casted into a
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* {@link Service}
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*
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* @param serviceName a string
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* @return an {@link Object}
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*/
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public Object lookup(String serviceName) {
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if (serviceName.equals("jndi/serviceA")) {
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System.out.println("Looking up service A and creating new service for A");
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return new ServiceImpl("jndi/serviceA");
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} else if (serviceName.equals("jndi/serviceB")) {
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System.out.println("Looking up service B and creating new service for B");
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return new ServiceImpl("jndi/serviceB");
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} else {
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return null;
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}
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}
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}
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@ -1,29 +1,26 @@
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package com.iluwatar.servicelocator;
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/**
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* This is going to be the parent service interface which we will
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* use to create our services. All services will have a
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* <li>service name</li>
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* <li>unique id</li>
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* <li>execution work flow</li>
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* This is going to be the parent service interface which we will use to create our services. All
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* services will have a <li>service name</li> <li>unique id</li> <li>execution work flow</li>
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*
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* @author saifasif
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*
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*/
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public interface Service {
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/*
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* The human readable name of the service
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*/
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String getName();
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/*
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* Unique ID of the particular service
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*/
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int getId();
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/*
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* The workflow method that defines what this service does
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*/
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void execute();
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/*
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* The human readable name of the service
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*/
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String getName();
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/*
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* Unique ID of the particular service
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*/
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int getId();
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/*
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* The workflow method that defines what this service does
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*/
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void execute();
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}
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@ -4,44 +4,45 @@ import java.util.HashMap;
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import java.util.Map;
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/**
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* The service cache implementation which will cache services that are being created.
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* On first hit, the cache will be empty and thus any service that is being requested, will be
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* created fresh and then placed into the cache map. On next hit, if same service name will
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* be requested, it will be returned from the cache
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* The service cache implementation which will cache services that are being created. On first hit,
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* the cache will be empty and thus any service that is being requested, will be created fresh and
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* then placed into the cache map. On next hit, if same service name will be requested, it will be
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* returned from the cache
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*
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* @author saifasif
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*/
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public class ServiceCache {
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private final Map<String, Service> serviceCache;
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private final Map<String, Service> serviceCache;
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public ServiceCache() {
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serviceCache = new HashMap<String, Service>();
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}
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public ServiceCache() {
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serviceCache = new HashMap<String, Service>();
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}
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/**
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* Get the service from the cache. null if no service is found matching the name
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*
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* @param serviceName a string
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* @return {@link Service}
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*/
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public Service getService(String serviceName) {
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Service cachedService = null;
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for (String serviceJndiName : serviceCache.keySet()) {
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if (serviceJndiName.equals(serviceName)) {
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cachedService = serviceCache.get(serviceJndiName);
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System.out.println("(cache call) Fetched service " + cachedService.getName() + "(" + cachedService.getId() + ") from cache... !");
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}
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}
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return cachedService;
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/**
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* Get the service from the cache. null if no service is found matching the name
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*
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* @param serviceName a string
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* @return {@link Service}
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*/
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public Service getService(String serviceName) {
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Service cachedService = null;
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for (String serviceJndiName : serviceCache.keySet()) {
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if (serviceJndiName.equals(serviceName)) {
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cachedService = serviceCache.get(serviceJndiName);
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System.out.println("(cache call) Fetched service " + cachedService.getName() + "("
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+ cachedService.getId() + ") from cache... !");
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}
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}
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return cachedService;
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}
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/**
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* Adds the service into the cache map
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*
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* @param newService a {@link Service}
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*/
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public void addService(Service newService) {
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serviceCache.put(newService.getName(), newService);
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}
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/**
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* Adds the service into the cache map
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*
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* @param newService a {@link Service}
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*/
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public void addService(Service newService) {
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serviceCache.put(newService.getName(), newService);
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}
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}
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@ -1,37 +1,37 @@
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package com.iluwatar.servicelocator;
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/**
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* This is a single service implementation of a sample service. This is the actual
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* service that will process the request. The reference for this service is to
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* be looked upon in the JNDI server that can be set in the web.xml deployment descriptor
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* This is a single service implementation of a sample service. This is the actual service that will
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* process the request. The reference for this service is to be looked upon in the JNDI server that
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* can be set in the web.xml deployment descriptor
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*
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* @author saifasif
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*/
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public class ServiceImpl implements Service {
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private final String serviceName;
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private final int id;
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private final String serviceName;
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private final int id;
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public ServiceImpl(String serviceName) {
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// set the service name
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this.serviceName = serviceName;
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public ServiceImpl(String serviceName) {
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// set the service name
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this.serviceName = serviceName;
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// Generate a random id to this service object
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this.id = (int) Math.floor(Math.random() * 1000) + 1;
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}
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// Generate a random id to this service object
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this.id = (int) Math.floor(Math.random() * 1000) + 1;
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}
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@Override
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public String getName() {
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return serviceName;
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}
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@Override
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public String getName() {
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return serviceName;
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}
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@Override
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public int getId() {
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return id;
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}
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@Override
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public int getId() {
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return id;
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}
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@Override
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public void execute() {
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System.out.println("Service " + getName() + " is now executing with id " + getId());
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}
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@Override
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public void execute() {
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System.out.println("Service " + getName() + " is now executing with id " + getId());
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}
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}
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@ -1,36 +1,36 @@
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package com.iluwatar.servicelocator;
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/**
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* The service locator module.
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* Will fetch service from cache, otherwise creates a fresh service and update cache
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* The service locator module. Will fetch service from cache, otherwise creates a fresh service and
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* update cache
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*
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* @author saifasif
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*/
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public class ServiceLocator {
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private static ServiceCache serviceCache = new ServiceCache();
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private static ServiceCache serviceCache = new ServiceCache();
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/**
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* Fetch the service with the name param from the cache first,
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* if no service is found, lookup the service from the {@link InitContext} and
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* then add the newly created service into the cache map for future requests.
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*
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* @param serviceJndiName a string
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* @return {@link Service}
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*/
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public static Service getService(String serviceJndiName) {
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Service serviceObj = serviceCache.getService(serviceJndiName);
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if (serviceObj != null) {
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return serviceObj;
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} else {
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/*
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* If we are unable to retrive anything from cache, then
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* lookup the service and add it in the cache map
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*/
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InitContext ctx = new InitContext();
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serviceObj = (Service) ctx.lookup(serviceJndiName);
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serviceCache.addService(serviceObj);
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return serviceObj;
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}
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/**
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* Fetch the service with the name param from the cache first, if no service is found, lookup the
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* service from the {@link InitContext} and then add the newly created service into the cache map
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* for future requests.
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*
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* @param serviceJndiName a string
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* @return {@link Service}
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*/
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public static Service getService(String serviceJndiName) {
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Service serviceObj = serviceCache.getService(serviceJndiName);
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if (serviceObj != null) {
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return serviceObj;
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} else {
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/*
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* If we are unable to retrive anything from cache, then lookup the service and add it in the
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* cache map
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*/
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InitContext ctx = new InitContext();
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serviceObj = (Service) ctx.lookup(serviceJndiName);
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serviceCache.addService(serviceObj);
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return serviceObj;
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}
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}
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}
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@ -11,9 +11,9 @@ import com.iluwatar.servicelocator.App;
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*/
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public class AppTest {
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@Test
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public void test() {
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String[] args = {};
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App.main(args);
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}
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@Test
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public void test() {
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String[] args = {};
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App.main(args);
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}
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}
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