Rxjava refactor (#2358)

* Refactor

* Refactor

rxjava/src/main/java/com/baelding/rxjava/operator/ToCleanString.java

@@ -3,9 +3,13 @@ package com.baelding.rxjava.operator;
 import rx.Observable.Operator;
 import rx.Subscriber;
 
-public class CleanString implements Operator<String, String> {
+public class ToCleanString implements Operator<String, String> {
 
-    public CleanString() {
+    public static ToCleanString toCleanString() {
+        return new ToCleanString();
+    }
+
+    private ToCleanString() {
         super();
     }
 

rxjava/src/main/java/com/baelding/rxjava/operator/ToLength.java

@@ -2,10 +2,14 @@ package com.baelding.rxjava.operator;
 
 import rx.Observable;
 import rx.Observable.Transformer;
-import rx.functions.Func1;
 
 public class ToLength implements Transformer<String, Integer> {
-    public ToLength() {
+
+    public static ToLength toLength() {
+        return new ToLength();
+    }
+
+    private ToLength() {
         super();
     }
 

rxjava/src/test/java/com/baeldung/rxjava/RxJavaBackpressureLongRunningUnitTest.java

@@ -34,7 +34,7 @@ public class RxJavaBackpressureLongRunningUnitTest {
     public void givenHotObservable_whenBackpressureNotDefined_shouldTrowException() {
         // given
         TestSubscriber<Integer> testSubscriber = new TestSubscriber<>();
-        PublishSubject<Integer> source = PublishSubject.<Integer> create();
+        PublishSubject<Integer> source = PublishSubject.create();
 
         source.observeOn(Schedulers.computation()).subscribe(testSubscriber);
 
@@ -50,7 +50,7 @@ public class RxJavaBackpressureLongRunningUnitTest {
     public void givenHotObservable_whenWindowIsDefined_shouldNotThrowException() {
         // given
         TestSubscriber<Observable<Integer>> testSubscriber = new TestSubscriber<>();
-        PublishSubject<Integer> source = PublishSubject.<Integer> create();
+        PublishSubject<Integer> source = PublishSubject.create();
 
         // when
         source.window(500).observeOn(Schedulers.computation()).subscribe(testSubscriber);
@@ -67,7 +67,7 @@ public class RxJavaBackpressureLongRunningUnitTest {
     public void givenHotObservable_whenBufferIsDefined_shouldNotThrowException() {
         // given
         TestSubscriber<List<Integer>> testSubscriber = new TestSubscriber<>();
-        PublishSubject<Integer> source = PublishSubject.<Integer> create();
+        PublishSubject<Integer> source = PublishSubject.create();
 
         // when
         source.buffer(1024).observeOn(Schedulers.computation()).subscribe(testSubscriber);
@@ -84,7 +84,7 @@ public class RxJavaBackpressureLongRunningUnitTest {
     public void givenHotObservable_whenSkippingOperationIsDefined_shouldNotThrowException() {
         // given
         TestSubscriber<Integer> testSubscriber = new TestSubscriber<>();
-        PublishSubject<Integer> source = PublishSubject.<Integer> create();
+        PublishSubject<Integer> source = PublishSubject.create();
 
         // when
         source.sample(100, TimeUnit.MILLISECONDS)

rxjava/src/test/java/com/baeldung/rxjava/RxJavaCustomOperatorUnitTest.java

@@ -1,5 +1,7 @@
 package com.baeldung.rxjava;
 
+import static com.baelding.rxjava.operator.ToCleanString.toCleanString;
+import static com.baelding.rxjava.operator.ToLength.toLength;
 import static org.hamcrest.Matchers.hasItems;
 import static org.hamcrest.Matchers.hasSize;
 import static org.hamcrest.Matchers.notNullValue;
@@ -16,7 +18,7 @@ import rx.Observable.Operator;
 import rx.Observable.Transformer;
 import rx.Subscriber;
 
-import com.baelding.rxjava.operator.CleanString;
+import com.baelding.rxjava.operator.ToCleanString;
 import com.baelding.rxjava.operator.ToLength;
 
 public class RxJavaCustomOperatorUnitTest {
@@ -24,10 +26,10 @@ public class RxJavaCustomOperatorUnitTest {
     @Test
     public void whenUseCleanStringOperator_thenSuccess() {
         final List<String> list = Arrays.asList("john_1", "tom-3");
-        final List<String> results = new ArrayList<String>();
+        final List<String> results = new ArrayList<>();
 
         final Observable<String> observable = Observable.from(list)
-            .lift(new CleanString());
+            .lift(toCleanString());
 
         // when
         observable.subscribe(results::add);
@@ -41,10 +43,10 @@ public class RxJavaCustomOperatorUnitTest {
     @Test
     public void whenUseToLengthOperator_thenSuccess() {
         final List<String> list = Arrays.asList("john", "tom");
-        final List<Integer> results = new ArrayList<Integer>();
+        final List<Integer> results = new ArrayList<>();
 
         final Observable<Integer> observable = Observable.from(list)
-            .compose(new ToLength());
+            .compose(toLength());
 
         // when
         observable.subscribe(results::add);
@@ -57,33 +59,31 @@ public class RxJavaCustomOperatorUnitTest {
 
     @Test
     public void whenUseFunctionOperator_thenSuccess() {
-        final Operator<String, String> cleanStringFn = subscriber -> {
+        final Operator<String, String> cleanStringFn = subscriber -> new Subscriber<String>(subscriber) {
-            return new Subscriber<String>(subscriber) {
+            @Override
-                @Override
+            public void onCompleted() {
-                public void onCompleted() {
+                if (!subscriber.isUnsubscribed()) {
-                    if (!subscriber.isUnsubscribed()) {
+                    subscriber.onCompleted();
-                        subscriber.onCompleted();
-                    }
                 }
+            }
 
-                @Override
+            @Override
-                public void onError(Throwable t) {
+            public void onError(Throwable t) {
-                    if (!subscriber.isUnsubscribed()) {
+                if (!subscriber.isUnsubscribed()) {
-                        subscriber.onError(t);
+                    subscriber.onError(t);
-                    }
                 }
+            }
 
-                @Override
+            @Override
-                public void onNext(String str) {
+            public void onNext(String str) {
-                    if (!subscriber.isUnsubscribed()) {
+                if (!subscriber.isUnsubscribed()) {
-                        final String result = str.replaceAll("[^A-Za-z0-9]", "");
+                    final String result = str.replaceAll("[^A-Za-z0-9]", "");
-                        subscriber.onNext(result);
+                    subscriber.onNext(result);
-                    }
                 }
-            };
+            }
         };
 
-        final List<String> results = new ArrayList<String>();
+        final List<String> results = new ArrayList<>();
         Observable.from(Arrays.asList("ap_p-l@e", "or-an?ge"))
             .lift(cleanStringFn)
             .subscribe(results::add);
@@ -97,7 +97,7 @@ public class RxJavaCustomOperatorUnitTest {
     public void whenUseFunctionTransformer_thenSuccess() {
         final Transformer<String, Integer> toLengthFn = source -> source.map(String::length);
 
-        final List<Integer> results = new ArrayList<Integer>();
+        final List<Integer> results = new ArrayList<>();
         Observable.from(Arrays.asList("apple", "orange"))
             .compose(toLengthFn)
             .subscribe(results::add);