Updated class diagram png and added UCLS file

ambassador/src/main/java/com/iluwatar/ambassador/RemoteService.java

@@ -22,7 +22,6 @@
  */
 package com.iluwatar.ambassador;
 
-import com.iluwatar.ambassador.util.RandomProvider;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -32,10 +31,9 @@ import static java.lang.Thread.sleep;
  * A remote legacy application represented by a Singleton implementation.
  */
 public class RemoteService implements RemoteServiceInterface {
-  static final int THRESHOLD = 200;
+
   private static final Logger LOGGER = LoggerFactory.getLogger(RemoteService.class);
   private static RemoteService service = null;
-  private final RandomProvider randomProvider;
 
   static synchronized RemoteService getRemoteService() {
     if (service == null) {
@@ -44,33 +42,24 @@ public class RemoteService implements RemoteServiceInterface {
     return service;
   }
 
-  private RemoteService() {
+  private RemoteService() {}
-    this(Math::random);
-  }
 
-  /**
-   * This constuctor is used for testing purposes only.
-   */
-  RemoteService(RandomProvider randomProvider) {
-    this.randomProvider = randomProvider;
-  }
   /**
    * Remote function takes a value and multiplies it by 10 taking a random amount of time.
    * Will sometimes return -1. This imitates connectivity issues a client might have to account for.
    * @param value integer value to be multiplied.
-   * @return if waitTime is less than {@link RemoteService#THRESHOLD}, it returns value * 10,
+   * @return if waitTime is more than 200ms, it returns value * 10, otherwise -1.
-   *     otherwise {@link RemoteServiceInterface#FAILURE}.
    */
   @Override
   public long doRemoteFunction(int value) {
 
-    long waitTime = (long) Math.floor(randomProvider.random() * 1000);
+    long waitTime = (long) Math.floor(Math.random() * 1000);
 
     try {
       sleep(waitTime);
     } catch (InterruptedException e) {
       LOGGER.error("Thread sleep state interrupted", e);
     }
-    return waitTime <= THRESHOLD ? value * 10 : FAILURE;
+    return waitTime >= 200 ? value * 10 : -1;
   }
 }

ambassador/src/main/java/com/iluwatar/ambassador/RemoteServiceInterface.java

@@ -26,7 +26,6 @@ package com.iluwatar.ambassador;
  * Interface shared by ({@link RemoteService}) and ({@link ServiceAmbassador}).
  */
 interface RemoteServiceInterface {
-  int FAILURE = -1;
+    
-
   long doRemoteFunction(int value) throws Exception;
 }

ambassador/src/main/java/com/iluwatar/ambassador/ServiceAmbassador.java

@@ -59,15 +59,15 @@ public class ServiceAmbassador implements RemoteServiceInterface {
   private long safeCall(int value) {
 
     int retries = 0;
-    long result = FAILURE;
+    long result = -1;
 
     for (int i = 0; i < RETRIES; i++) {
 
       if (retries >= RETRIES) {
-        return FAILURE;
+        return -1;
       }
 
-      if ((result = checkLatency(value)) == FAILURE) {
+      if ((result = checkLatency(value)) == -1) {
         LOGGER.info("Failed to reach remote: (" + (i + 1) + ")");
         retries++;
         try {

ambassador/src/main/java/com/iluwatar/ambassador/util/RandomProvider.java

@@ -1,8 +0,0 @@
-package com.iluwatar.ambassador.util;
-
-/**
- * An interface for randomness. Useful for testing purposes.
- */
-public interface RandomProvider {
-  double random();
-}

ambassador/src/test/java/com/iluwatar/ambassador/ClientTest.java

@@ -24,8 +24,6 @@ package com.iluwatar.ambassador;
 
 import org.junit.jupiter.api.Test;
 
-import static org.junit.jupiter.api.Assertions.assertTrue;
-
 /**
  * Test for {@link Client}
  */
@@ -37,6 +35,6 @@ public class ClientTest {
     Client client = new Client();
     long result = client.useService(10);
 
-    assertTrue(result == 100 || result == RemoteService.FAILURE);
+    assert result == 100 || result == -1;
   }
 }

ambassador/src/test/java/com/iluwatar/ambassador/RemoteServiceTest.java

@@ -22,43 +22,16 @@
  */
 package com.iluwatar.ambassador;
 
-import com.iluwatar.ambassador.util.RandomProvider;
 import org.junit.jupiter.api.Test;
 
-import static org.junit.jupiter.api.Assertions.assertEquals;
-import static org.junit.jupiter.api.Assertions.assertTrue;
-
 /**
  * Test for {@link RemoteService}
  */
 public class RemoteServiceTest {
 
   @Test
-  public void testFailedCall() {
+  public void test() {
-    RemoteService remoteService = new RemoteService(
+    long result = RemoteService.getRemoteService().doRemoteFunction(10);
-        new StaticRandomProvider(0.21));
+    assert result == 100 || result == -1;
-    long result = remoteService.doRemoteFunction(10);
-    assertEquals(RemoteServiceInterface.FAILURE, result);
-  }
-
-  @Test
-  public void testSuccessfulCall() {
-    RemoteService remoteService = new RemoteService(
-        new StaticRandomProvider(0.2));
-    long result = remoteService.doRemoteFunction(10);
-    assertEquals(100, result);
-  }
-
-  private class StaticRandomProvider implements RandomProvider {
-    private double value;
-
-    StaticRandomProvider(double value) {
-      this.value = value;
-    }
-
-    @Override
-    public double random() {
-      return value;
-    }
   }
 }

ambassador/src/test/java/com/iluwatar/ambassador/ServiceAmbassadorTest.java

@@ -24,8 +24,6 @@ package com.iluwatar.ambassador;
 
 import org.junit.jupiter.api.Test;
 
-import static org.junit.jupiter.api.Assertions.assertTrue;
-
 /**
  * Test for {@link ServiceAmbassador}
  */
@@ -34,6 +32,6 @@ public class ServiceAmbassadorTest {
   @Test
   public void test() {
     long result = new ServiceAmbassador().doRemoteFunction(10);
-    assertTrue(result == 100 || result == RemoteServiceInterface.FAILURE);
+    assert result == 100 || result == -1;
   }
 }

throttling/etc/throttling-pattern.ucls

@@ -0,0 +1,88 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<class-diagram version="1.2.2" icons="true" always-add-relationships="false" generalizations="true" realizations="true" 
+  associations="true" dependencies="false" nesting-relationships="true" router="FAN">  
+  <class id="1" language="java" name="com.iluwatar.throttling.CallsCount" project="throttling" 
+    file="/throttling/src/main/java/com/iluwatar/throttling/CallsCount.java" binary="false" corner="BOTTOM_RIGHT">    
+    <position height="211" width="256" x="656" y="228"/>    
+    <display autosize="false" stereotype="true" package="true" initial-value="false" signature="true" 
+      sort-features="false" accessors="true" visibility="true">      
+      <attributes public="true" package="true" protected="true" private="true" static="true"/>      
+      <operations public="true" package="true" protected="true" private="true" static="true"/>    
+    </display>  
+  </class>  
+  <class id="2" language="java" name="com.iluwatar.throttling.Tenant" project="throttling" 
+    file="/throttling/src/main/java/com/iluwatar/throttling/Tenant.java" binary="false" corner="BOTTOM_RIGHT">    
+    <position height="-1" width="-1" x="465" y="524"/>    
+    <display autosize="true" stereotype="true" package="true" initial-value="false" signature="true" 
+      sort-features="false" accessors="true" visibility="true">      
+      <attributes public="true" package="true" protected="true" private="true" static="true"/>      
+      <operations public="true" package="true" protected="true" private="true" static="true"/>    
+    </display>  
+  </class>  
+  <class id="3" language="java" name="com.iluwatar.throttling.B2BService" project="throttling" 
+    file="/throttling/src/main/java/com/iluwatar/throttling/B2BService.java" binary="false" corner="BOTTOM_RIGHT">    
+    <position height="-1" width="-1" x="464" y="192"/>    
+    <display autosize="true" stereotype="true" package="true" initial-value="false" signature="true" 
+      sort-features="false" accessors="true" visibility="true">      
+      <attributes public="true" package="true" protected="true" private="true" static="true"/>      
+      <operations public="true" package="true" protected="true" private="true" static="true"/>    
+    </display>  
+  </class>  
+  <interface id="4" language="java" name="com.iluwatar.throttling.timer.Throttler" project="throttling" 
+    file="/throttling/src/main/java/com/iluwatar/throttling/timer/Throttler.java" binary="false" corner="BOTTOM_RIGHT">    
+    <position height="-1" width="-1" x="167" y="174"/>    
+    <display autosize="true" stereotype="true" package="true" initial-value="false" signature="true" 
+      sort-features="false" accessors="true" visibility="true">      
+      <attributes public="true" package="true" protected="true" private="true" static="true"/>      
+      <operations public="true" package="true" protected="true" private="true" static="true"/>    
+    </display>  
+  </interface>  
+  <class id="5" language="java" name="com.iluwatar.throttling.timer.ThrottleTimerImpl" project="throttling" 
+    file="/throttling/src/main/java/com/iluwatar/throttling/timer/ThrottleTimerImpl.java" binary="false" 
+    corner="BOTTOM_RIGHT">    
+    <position height="-1" width="-1" x="166" y="396"/>    
+    <display autosize="true" stereotype="true" package="true" initial-value="false" signature="true" 
+      sort-features="false" accessors="true" visibility="true">      
+      <attributes public="true" package="true" protected="true" private="true" static="true"/>      
+      <operations public="true" package="true" protected="true" private="true" static="true"/>    
+    </display>  
+  </class>  
+  <association id="6">    
+    <end type="SOURCE" refId="3" navigable="false">      
+      <attribute id="7" name="callsCount"/>      
+      <multiplicity id="8" minimum="0" maximum="1"/>    
+    </end>    
+    <end type="TARGET" refId="1" navigable="true"/>    
+    <display labels="true" multiplicity="true"/>  
+  </association>  
+  <dependency id="9">    
+    <end type="SOURCE" refId="3"/>    
+    <end type="TARGET" refId="4"/>  
+  </dependency>  
+  <dependency id="10">    
+    <end type="SOURCE" refId="3"/>    
+    <end type="TARGET" refId="2"/>  
+  </dependency>  
+  <association id="11">    
+    <end type="SOURCE" refId="5" navigable="false">      
+      <attribute id="12" name="callsCount"/>      
+      <multiplicity id="13" minimum="0" maximum="1"/>    
+    </end>    
+    <end type="TARGET" refId="1" navigable="true"/>    
+    <display labels="true" multiplicity="true"/>  
+  </association>  
+  <dependency id="14">    
+    <end type="SOURCE" refId="2"/>    
+    <end type="TARGET" refId="1"/>  
+  </dependency>  
+  <realization id="15">    
+    <end type="SOURCE" refId="5"/>    
+    <end type="TARGET" refId="4"/>  
+  </realization>  
+  <classifier-display autosize="true" stereotype="true" package="true" initial-value="false" signature="true" 
+    sort-features="false" accessors="true" visibility="true">    
+    <attributes public="true" package="true" protected="true" private="true" static="true"/>    
+    <operations public="true" package="true" protected="true" private="true" static="true"/>  
+  </classifier-display>  
+  <association-display labels="true" multiplicity="true"/>
+</class-diagram>

throttling/src/main/java/com/iluwatar/throttling/App.java

@@ -53,14 +53,14 @@ public class App {
    * @param args main arguments
    */
   public static void main(String[] args) {
-
+    CallsCount callsCount = new CallsCount();
-    Tenant adidas = new Tenant("Adidas", 5);
+    Tenant adidas = new Tenant("Adidas", 5, callsCount);
-    Tenant nike = new Tenant("Nike", 6);
+    Tenant nike = new Tenant("Nike", 6, callsCount);
 
     ExecutorService executorService = Executors.newFixedThreadPool(2);
     
-    executorService.execute(() -> makeServiceCalls(adidas));
+    executorService.execute(() -> makeServiceCalls(adidas, callsCount));
-    executorService.execute(() -> makeServiceCalls(nike));
+    executorService.execute(() -> makeServiceCalls(nike, callsCount));
     
     executorService.shutdown();
     try {
@@ -73,9 +73,9 @@ public class App {
   /**
    * Make calls to the B2BService dummy API
    */
-  private static void makeServiceCalls(Tenant tenant) {
+  private static void makeServiceCalls(Tenant tenant, CallsCount callsCount) {
-    Throttler timer = new ThrottleTimerImpl(10);
+    Throttler timer = new ThrottleTimerImpl(10, callsCount);
-    B2BService service = new B2BService(timer);
+    B2BService service = new B2BService(timer, callsCount);
     for (int i = 0; i < 20; i++) {
       service.dummyCustomerApi(tenant);
 //    Sleep is introduced to keep the output in check and easy to view and analyze the results.

throttling/src/main/java/com/iluwatar/throttling/B2BService.java

@@ -35,8 +35,10 @@ import java.util.concurrent.ThreadLocalRandom;
 class B2BService {
 
   private static final Logger LOGGER = LoggerFactory.getLogger(B2BService.class);
+  private final CallsCount callsCount;
 
-  public B2BService(Throttler timer) {
+  public B2BService(Throttler timer, CallsCount callsCount) {
+    this.callsCount = callsCount;
     timer.start();
   }
 
@@ -46,13 +48,13 @@ class B2BService {
    */
   public int dummyCustomerApi(Tenant tenant) {
     String tenantName = tenant.getName();
-    long count = CallsCount.getCount(tenantName);
+    long count = callsCount.getCount(tenantName);
     LOGGER.debug("Counter for {} : {} ", tenant.getName(), count);
     if (count >= tenant.getAllowedCallsPerSecond()) {
       LOGGER.error("API access per second limit reached for: {}", tenantName);
       return -1;
     }
-    CallsCount.incrementCount(tenantName);
+    callsCount.incrementCount(tenantName);
     return getRandomCustomerId();
   }
 

throttling/src/main/java/com/iluwatar/throttling/CallsCount.java

@@ -38,13 +38,13 @@ import java.util.concurrent.atomic.AtomicLong;
 public final class CallsCount {
 
   private static final Logger LOGGER = LoggerFactory.getLogger(CallsCount.class);
-  private static Map<String, AtomicLong> tenantCallsCount = new ConcurrentHashMap<>();
+  private Map<String, AtomicLong> tenantCallsCount = new ConcurrentHashMap<>();
 
   /**
    * Add a new tenant to the map.
    * @param tenantName name of the tenant.
    */
-  public static void addTenant(String tenantName) {
+  public void addTenant(String tenantName) {
     tenantCallsCount.putIfAbsent(tenantName, new AtomicLong(0));
   }
   
@@ -52,7 +52,7 @@ public final class CallsCount {
    * Increment the count of the specified tenant.
    * @param tenantName name of the tenant.
    */
-  public static void incrementCount(String tenantName) {
+  public void incrementCount(String tenantName) {
     tenantCallsCount.get(tenantName).incrementAndGet();
   }
   
@@ -61,14 +61,14 @@ public final class CallsCount {
    * @param tenantName name of the tenant.
    * @return the count of the tenant.
    */
-  public static long getCount(String tenantName) {
+  public long getCount(String tenantName) {
     return tenantCallsCount.get(tenantName).get();
   }
   
   /**
    * Resets the count of all the tenants in the map.
    */
-  public static void reset() {
+  public void reset() {
     LOGGER.debug("Resetting the map.");
     for (Entry<String, AtomicLong> e : tenantCallsCount.entrySet()) {
       tenantCallsCount.put(e.getKey(), new AtomicLong(0));

throttling/src/main/java/com/iluwatar/throttling/Tenant.java

@@ -38,13 +38,13 @@ public class Tenant {
    * @param allowedCallsPerSecond The number of calls allowed for a particular tenant.
    * @throws InvalidParameterException If number of calls is less than 0, throws exception.
    */
-  public Tenant(String name, int allowedCallsPerSecond) {
+  public Tenant(String name, int allowedCallsPerSecond, CallsCount callsCount) {
     if (allowedCallsPerSecond < 0) {
       throw new InvalidParameterException("Number of calls less than 0 not allowed");
     }
     this.name = name;
     this.allowedCallsPerSecond = allowedCallsPerSecond;
-    CallsCount.addTenant(name);
+    callsCount.addTenant(name);
   }
 
   public String getName() {

throttling/src/main/java/com/iluwatar/throttling/timer/ThrottleTimerImpl.java

@@ -37,10 +37,12 @@ import com.iluwatar.throttling.CallsCount;
  */
 public class ThrottleTimerImpl implements Throttler {
 
-  private int throttlePeriod;
+  private final int throttlePeriod;
-  
+  private final CallsCount callsCount;
-  public ThrottleTimerImpl(int throttlePeriod) {
+
+  public ThrottleTimerImpl(int throttlePeriod, CallsCount callsCount) {
     this.throttlePeriod = throttlePeriod;
+    this.callsCount = callsCount;
   }
   
   /**
@@ -51,7 +53,7 @@ public class ThrottleTimerImpl implements Throttler {
     new Timer(true).schedule(new TimerTask() {
       @Override
       public void run() {
-        CallsCount.reset();
+        callsCount.reset();
       }
     }, 0, throttlePeriod);
   }

throttling/src/test/java/com/iluwatar/throttling/B2BServiceTest.java

@@ -33,18 +33,19 @@ import static org.junit.jupiter.api.Assertions.assertEquals;
  */
 public class B2BServiceTest {
 
-  @Disabled
+  private CallsCount callsCount = new CallsCount();
+
   @Test
   public void dummyCustomerApiTest() {
-    Tenant tenant = new Tenant("testTenant", 2);
+    Tenant tenant = new Tenant("testTenant", 2, callsCount);
     // In order to assure that throttling limits will not be reset, we use an empty throttling implementation
     Throttler timer = () -> { };
-    B2BService service = new B2BService(timer);
+    B2BService service = new B2BService(timer, callsCount);
 
     for (int i = 0; i < 5; i++) {
       service.dummyCustomerApi(tenant);
     }
-    long counter = CallsCount.getCount(tenant.getName());
+    long counter = callsCount.getCount(tenant.getName());
     assertEquals(2, counter, "Counter limit must be reached");
   }
 }

throttling/src/test/java/com/iluwatar/throttling/TenantTest.java

@@ -36,7 +36,7 @@ public class TenantTest {
   @Test
   public void constructorTest() {
     assertThrows(InvalidParameterException.class, () -> {
-      Tenant tenant = new Tenant("FailTenant", -1);
+      Tenant tenant = new Tenant("FailTenant", -1, new CallsCount());
     });
   }
 }