2.x: cleanup of PMD suggestions (ReactiveX#4129)

pmd.xml

@@ -71,7 +71,6 @@
    <rule ref="rulesets/java/basic.xml/DontUseFloatTypeForLoopIndices"/>
    <rule ref="rulesets/java/basic.xml/DoubleCheckedLocking"/>
    <rule ref="rulesets/java/imports.xml/DuplicateImports"/>
-   <rule ref="rulesets/java/empty.xml/EmptyCatchBlock"/>
    <rule ref="rulesets/java/finalizers.xml/EmptyFinalizer"/>
    <rule ref="rulesets/java/empty.xml/EmptyFinallyBlock"/>
    <rule ref="rulesets/java/empty.xml/EmptyInitializer"/>
@@ -110,7 +109,6 @@
    <rule ref="rulesets/java/migrating.xml/JUnit4SuitesShouldUseSuiteAnnotation"/>
    <rule ref="rulesets/java/migrating.xml/JUnit4TestShouldUseAfterAnnotation"/>
    <rule ref="rulesets/java/migrating.xml/JUnit4TestShouldUseBeforeAnnotation"/>
-   <rule ref="rulesets/java/migrating.xml/JUnit4TestShouldUseTestAnnotation"/>
    <rule ref="rulesets/java/junit.xml/JUnitAssertionsShouldIncludeMessage"/>
    <rule ref="rulesets/java/junit.xml/JUnitSpelling"/>
    <rule ref="rulesets/java/junit.xml/JUnitStaticSuite"/>
@@ -134,9 +132,6 @@
    <rule ref="rulesets/java/javabeans.xml/MissingSerialVersionUID"/>
    <rule ref="rulesets/java/design.xml/MissingStaticMethodInNonInstantiatableClass"/>
    <rule ref="rulesets/java/logging-java.xml/MoreThanOneLogger"/>
-   <rule ref="rulesets/java/codesize.xml/NcssConstructorCount"/>
-   <rule ref="rulesets/java/codesize.xml/NcssMethodCount"/>
-   <rule ref="rulesets/java/codesize.xml/NcssTypeCount"/>
    <rule ref="rulesets/java/naming.xml/NoPackage"/>
    <rule ref="rulesets/java/design.xml/NonCaseLabelInSwitchStatement"/>
    <rule ref="rulesets/java/design.xml/NonStaticInitializer"/>
@@ -160,7 +155,6 @@
    <rule ref="rulesets/java/design.xml/ReturnEmptyArrayRatherThanNull"/>
    <rule ref="rulesets/java/basic.xml/ReturnFromFinallyBlock"/>
    <rule ref="rulesets/java/migrating.xml/ShortInstantiation"/>
-   <rule ref="rulesets/java/naming.xml/ShortMethodName"/>
    <rule ref="rulesets/java/strictexception.xml/SignatureDeclareThrowsException"/>
    <rule ref="rulesets/java/design.xml/SimpleDateFormatNeedsLocale"/>
    <rule ref="rulesets/java/junit.xml/SimplifyBooleanAssertion"/>
@@ -183,8 +177,6 @@
    <rule ref="rulesets/java/junit.xml/TestClassWithoutTestCases"/>
    <rule ref="rulesets/java/design.xml/TooFewBranchesForASwitchStatement"/>
    <rule ref="rulesets/java/imports.xml/TooManyStaticImports"/>
-   <rule ref="rulesets/java/design.xml/UncommentedEmptyConstructor"/>
-   <rule ref="rulesets/java/design.xml/UncommentedEmptyMethodBody"/>
    <rule ref="rulesets/java/basic.xml/UnconditionalIfStatement"/>
    <rule ref="rulesets/java/junit.xml/UnnecessaryBooleanAssertion"/>
    <rule ref="rulesets/java/strings.xml/UnnecessaryCaseChange"/>

src/main/java/io/reactivex/Completable.java

@@ -31,6 +31,12 @@
  * The class follows a similar event pattern as Reactive-Streams: onSubscribe (onError|onComplete)?
  */
 public abstract class Completable implements CompletableConsumable {
+    /** Single instance of a complete Completable. */
+    static final Completable COMPLETE = new CompletableEmpty();
+
+    /** Single instance of a never Completable. */
+    static final Completable NEVER = new CompletableNever();
+
     /**
      * Convenience interface and callback used by the lift operator that given a child CompletableSubscriber,
      * return a parent CompletableSubscriber that does any kind of lifecycle-related transformations.
@@ -47,12 +53,6 @@ public interface CompletableTransformer extends Function<Completable, Completabl
 
     }
 
-    /** Single instance of a complete Completable. */
-    static final Completable COMPLETE = new CompletableEmpty();
-
-    /** Single instance of a never Completable. */
-    static final Completable NEVER = new CompletableNever();
-
     /**
      * Wraps the given CompletableConsumable into a Completable
      * if not already Completable.
@@ -186,7 +186,7 @@ public static Completable create(CompletableConsumable onSubscribe) {
             // TODO plugin wrapping onSubscribe
 
             return new CompletableWrapper(onSubscribe);
-        } catch (NullPointerException ex) {
+        } catch (NullPointerException ex) { // NOPMD
             throw ex;
         } catch (Throwable ex) {
             RxJavaPlugins.onError(ex);
@@ -1038,7 +1038,7 @@ public final void subscribe(CompletableSubscriber s) {
             // TODO plugin wrapping the subscriber
 
             subscribeActual(s);
-        } catch (NullPointerException ex) {
+        } catch (NullPointerException ex) { // NOPMD
             throw ex;
         } catch (Throwable ex) {
             RxJavaPlugins.onError(ex);

src/main/java/io/reactivex/Flowable.java

@@ -33,6 +33,13 @@
 import io.reactivex.subscribers.*;
 
 public abstract class Flowable<T> implements Publisher<T> {
+    private static final Object OBJECT = new Object(); 
+    /** The default buffer size. */
+    static final int BUFFER_SIZE;
+    static {
+        BUFFER_SIZE = Math.max(16, Integer.getInteger("rx2.buffer-size", 128));
+    }
+
     /**
      * Interface to map/wrap a downstream subscriber to an upstream subscriber.
      *
@@ -53,12 +60,6 @@ public interface Transformer<T, R> extends Function<Flowable<T>, Publisher<? ext
 
     }
 
-    /** The default buffer size. */
-    static final int BUFFER_SIZE;
-    static {
-        BUFFER_SIZE = Math.max(16, Integer.getInteger("rx2.buffer-size", 128));
-    }
-
     /** A never observable instance as there is no need to instantiate this more than once. */
     static final Flowable<Object> NEVER = create(new Publisher<Object>() {
         @Override
@@ -459,8 +460,7 @@ public static <T> Flowable<T> fromFuture(Future<? extends T> future) {
     public static <T> Flowable<T> fromFuture(Future<? extends T> future, long timeout, TimeUnit unit) {
         Objects.requireNonNull(future, "future is null");
         Objects.requireNonNull(unit, "unit is null");
-        Flowable<T> o = new FlowableFromFuture<T>(future, timeout, unit);
-        return o;
+        return new FlowableFromFuture<T>(future, timeout, unit);
     }
 
     @BackpressureSupport(BackpressureKind.FULL)
@@ -1613,16 +1613,14 @@ public Publisher<T> apply(Long v) {
         });
     }
 
-    private static final Object OBJECT = new Object(); 
-
     @SuppressWarnings({ "rawtypes", "unchecked" })
     @BackpressureSupport(BackpressureKind.FULL)
     @SchedulerSupport(SchedulerSupport.NONE)
     public final <U> Flowable<T> delaySubscription(final Supplier<? extends Publisher<U>> delaySupplier) {
         Objects.requireNonNull(delaySupplier, "delaySupplier is null");
         return fromCallable(new Callable<Object>() {
             @Override
-            public Object call() throws Exception {
+            public Object call() {
                 return delaySupplier.get();
             }
         })  
@@ -2936,7 +2934,7 @@ public final void subscribe(Subscriber<? super T> s) {
             }
 
             subscribeActual(s);
-        } catch (NullPointerException e) {
+        } catch (NullPointerException e) { // NOPMD
             throw e;
         } catch (Throwable e) {
             // TODO throw if fatal?

src/main/java/io/reactivex/Notification.java

@@ -19,12 +19,12 @@
  * Utility class to help construct notification objects.
  */
 public final class Notification {
+    static final Try<Optional<Object>> COMPLETE = Try.ofValue(Optional.<Object>empty());
+
     private Notification() {
         throw new IllegalStateException();
     }
 
-    static final Try<Optional<Object>> COMPLETE = Try.ofValue(Optional.<Object>empty());
-
     @SuppressWarnings({ "rawtypes", "unchecked" })
     public static <T> Try<Optional<T>> complete() {
         return (Try)COMPLETE;