Merge branch 'master' of https://gitbox.apache.org/repos/asf/commons-collections.git

src/main/java/org/apache/commons/collections4/bidimap/AbstractDualBidiMap.java

@@ -19,8 +19,8 @@ package org.apache.commons.collections4.bidimap;
 import java.util.Collection;
 import java.util.Iterator;
 import java.util.Map;
-import java.util.Set;
 import java.util.Objects;
+import java.util.Set;
 import java.util.function.Predicate;
 
 import org.apache.commons.collections4.BidiMap;

src/main/java/org/apache/commons/collections4/map/CompositeMap.java

@@ -17,14 +17,13 @@
 package org.apache.commons.collections4.map;
 
 import java.io.Serializable;
-
 import java.util.Collection;
 import java.util.Map;
 import java.util.Set;
 
-import org.apache.commons.collections4.set.CompositeSet;
 import org.apache.commons.collections4.CollectionUtils;
 import org.apache.commons.collections4.collection.CompositeCollection;
+import org.apache.commons.collections4.set.CompositeSet;
 
 /**
  * Decorates a map of other maps to provide a single unified view.

src/main/java/org/apache/commons/collections4/multimap/AbstractMultiValuedMap.java

@@ -26,8 +26,8 @@ import java.util.ArrayList;
 import java.util.Collection;
 import java.util.Iterator;
 import java.util.Map;
-import java.util.Objects;
 import java.util.Map.Entry;
+import java.util.Objects;
 import java.util.Set;
 
 import org.apache.commons.collections4.CollectionUtils;

src/main/java/org/apache/commons/collections4/multimap/AbstractMultiValuedMapDecorator.java

@@ -19,8 +19,8 @@ package org.apache.commons.collections4.multimap;
 import java.io.Serializable;
 import java.util.Collection;
 import java.util.Map;
-import java.util.Objects;
 import java.util.Map.Entry;
+import java.util.Objects;
 import java.util.Set;
 
 import org.apache.commons.collections4.MapIterator;

src/main/java/org/apache/commons/collections4/set/CompositeSet.java

@@ -23,8 +23,8 @@ import java.util.Collection;
 import java.util.HashSet;
 import java.util.Iterator;
 import java.util.List;
-import java.util.Set;
 import java.util.Objects;
+import java.util.Set;
 import java.util.function.Predicate;
 
 import org.apache.commons.collections4.CollectionUtils;

src/main/java/org/apache/commons/collections4/trie/AbstractBitwiseTrie.java

@@ -20,7 +20,6 @@ import java.io.Serializable;
 import java.util.AbstractMap;
 import java.util.Map;
 import java.util.Objects;
-import java.util.Map.Entry;
 
 import org.apache.commons.collections4.Trie;
 

src/test/java/org/apache/commons/collections4/AbstractObjectTest.java

@@ -16,8 +16,6 @@
  */
 package org.apache.commons.collections4;
 
-import org.junit.jupiter.api.Test;
-
 import java.io.ByteArrayInputStream;
 import java.io.ByteArrayOutputStream;
 import java.io.File;
@@ -30,6 +28,8 @@ import java.io.ObjectOutputStream;
 import java.io.OutputStream;
 import java.io.Serializable;
 
+import org.junit.jupiter.api.Test;
+
 /**
  * Abstract test class for {@link java.lang.Object} methods and contracts.
  * <p>

src/test/java/org/apache/commons/collections4/CollectionUtilsTest.java

@@ -23,8 +23,8 @@ import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.junit.jupiter.api.Assertions.assertFalse;
 import static org.junit.jupiter.api.Assertions.assertNull;
 import static org.junit.jupiter.api.Assertions.assertSame;
-import static org.junit.jupiter.api.Assertions.assertTrue;
 import static org.junit.jupiter.api.Assertions.assertThrows;
+import static org.junit.jupiter.api.Assertions.assertTrue;
 
 import java.util.ArrayList;
 import java.util.Arrays;
@@ -54,6 +54,7 @@ import org.apache.commons.collections4.collection.TransformedCollection;
 import org.apache.commons.collections4.collection.UnmodifiableCollection;
 import org.apache.commons.collections4.functors.DefaultEquator;
 import org.apache.commons.collections4.queue.CircularFifoQueue;
+import org.apache.commons.lang3.ArrayUtils;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 
@@ -1029,7 +1030,7 @@ public class CollectionUtilsTest extends MockTestCase {
     @Test
     public void reverse() {
         CollectionUtils.reverseArray(new Object[] {});
-        final Integer[] a = collectionA.toArray(new Integer[collectionA.size()]);
+        final Integer[] a = collectionA.toArray(ArrayUtils.EMPTY_INTEGER_OBJECT_ARRAY);
         CollectionUtils.reverseArray(a);
         // assume our implementation is correct if it returns the same order as the Java function
         Collections.reverse(collectionA);

src/test/java/org/apache/commons/collections4/IterableUtilsTest.java

@@ -23,9 +23,9 @@ import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.junit.jupiter.api.Assertions.assertFalse;
 import static org.junit.jupiter.api.Assertions.assertNull;
 import static org.junit.jupiter.api.Assertions.assertSame;
+import static org.junit.jupiter.api.Assertions.assertThrows;
 import static org.junit.jupiter.api.Assertions.assertTrue;
 import static org.junit.jupiter.api.Assertions.fail;
-import static org.junit.jupiter.api.Assertions.assertThrows;
 
 import java.util.ArrayList;
 import java.util.Arrays;

src/test/java/org/apache/commons/collections4/IteratorUtilsTest.java

@@ -26,27 +26,36 @@ import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.junit.jupiter.api.Assertions.assertFalse;
 import static org.junit.jupiter.api.Assertions.assertNull;
 import static org.junit.jupiter.api.Assertions.assertSame;
-import static org.junit.jupiter.api.Assertions.assertTrue;
 import static org.junit.jupiter.api.Assertions.assertThrows;
+import static org.junit.jupiter.api.Assertions.assertTrue;
 
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collection;
 import java.util.Collections;
 import java.util.Comparator;
+import java.util.Dictionary;
+import java.util.Enumeration;
 import java.util.HashMap;
 import java.util.Iterator;
+import java.util.LinkedHashSet;
 import java.util.List;
 import java.util.ListIterator;
 import java.util.Map;
 import java.util.NoSuchElementException;
-import java.util.Vector;
-import java.util.Dictionary;
-import java.util.Enumeration;
 import java.util.Set;
-import java.util.LinkedHashSet;
+import java.util.Vector;
 
-import org.apache.commons.collections4.iterators.*;
+import org.apache.commons.collections4.iterators.ArrayIterator;
+import org.apache.commons.collections4.iterators.EmptyIterator;
+import org.apache.commons.collections4.iterators.EmptyListIterator;
+import org.apache.commons.collections4.iterators.EmptyMapIterator;
+import org.apache.commons.collections4.iterators.EmptyOrderedIterator;
+import org.apache.commons.collections4.iterators.EmptyOrderedMapIterator;
+import org.apache.commons.collections4.iterators.EnumerationIterator;
+import org.apache.commons.collections4.iterators.NodeListIterator;
+import org.apache.commons.collections4.iterators.ObjectArrayIterator;
+import org.apache.commons.collections4.iterators.ZippingIterator;
 import org.apache.commons.collections4.map.EntrySetToMapIteratorAdapter;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;

src/test/java/org/apache/commons/collections4/MapUtilsTest.java

@@ -43,6 +43,7 @@ import java.util.ResourceBundle;
 import java.util.Set;
 import java.util.SortedMap;
 import java.util.TreeMap;
+
 import org.apache.commons.collections4.collection.TransformedCollectionTest;
 import org.apache.commons.collections4.keyvalue.DefaultKeyValue;
 import org.apache.commons.collections4.keyvalue.DefaultMapEntry;
@@ -166,7 +167,7 @@ public class MapUtilsTest {
                 () -> assertThrows(NullPointerException.class, () -> MapUtils.putAll(null, new Object[0]))
         );
 
-        Map<String, String> test = MapUtils.putAll(new HashMap<String, String>(), new String[0]);
+        Map<String, String> test = MapUtils.putAll(new HashMap<String, String>(), org.apache.commons.lang3.ArrayUtils.EMPTY_STRING_ARRAY);
         assertEquals(0, test.size());
 
         // sub array

src/test/java/org/apache/commons/collections4/PredicateUtilsTest.java

@@ -16,8 +16,8 @@
  */
 package org.apache.commons.collections4;
 
-import static org.apache.commons.collections4.functors.NullPredicate.*;
-import static org.apache.commons.collections4.functors.TruePredicate.*;
+import static org.apache.commons.collections4.functors.NullPredicate.nullPredicate;
+import static org.apache.commons.collections4.functors.TruePredicate.truePredicate;
 import static org.junit.jupiter.api.Assertions.assertFalse;
 import static org.junit.jupiter.api.Assertions.assertNotNull;
 import static org.junit.jupiter.api.Assertions.assertSame;

src/test/java/org/apache/commons/collections4/bag/AbstractBagTest.java

@@ -16,6 +16,9 @@
  */
 package org.apache.commons.collections4.bag;
 
+import static org.junit.jupiter.api.Assertions.assertNotEquals;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+
 import java.io.IOException;
 import java.io.Serializable;
 import java.util.ArrayList;
@@ -32,11 +35,9 @@ import org.apache.commons.collections4.Bag;
 import org.apache.commons.collections4.BulkTest;
 import org.apache.commons.collections4.collection.AbstractCollectionTest;
 import org.apache.commons.collections4.set.AbstractSetTest;
+import org.apache.commons.lang3.ArrayUtils;
 import org.junit.jupiter.api.Test;
 
-import static org.junit.jupiter.api.Assertions.assertNotEquals;
-import static org.junit.jupiter.api.Assertions.assertThrows;
-
 /**
  * Abstract test class for {@link org.apache.commons.collections4.Bag Bag} methods and contracts.
  * <p>
@@ -503,7 +504,7 @@ public abstract class AbstractBagTest<T> extends AbstractCollectionTest<T> {
         bag.add((T) "B");
         bag.add((T) "B");
         bag.add((T) "C");
-        final String[] array = bag.toArray(new String[0]);
+        final String[] array = bag.toArray(ArrayUtils.EMPTY_STRING_ARRAY);
         int a = 0, b = 0, c = 0;
         for (final String element : array) {
             a += element.equals("A") ? 1 : 0;

src/test/java/org/apache/commons/collections4/bloomfilter/AbstractCountingBloomFilterTest.java

@@ -16,10 +16,10 @@
  */
 package org.apache.commons.collections4.bloomfilter;
 
+import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.junit.jupiter.api.Assertions.assertFalse;
 import static org.junit.jupiter.api.Assertions.assertThrows;
 import static org.junit.jupiter.api.Assertions.assertTrue;
-import static org.junit.jupiter.api.Assertions.assertEquals;
 
 import java.util.HashMap;
 import java.util.Map;

src/test/java/org/apache/commons/collections4/bloomfilter/AbstractIndexProducerTest.java

@@ -22,6 +22,7 @@ import static org.junit.jupiter.api.Assertions.assertTrue;
 import java.util.Arrays;
 import java.util.BitSet;
 import java.util.function.IntPredicate;
+
 import org.junit.jupiter.api.Assertions;
 import org.junit.jupiter.api.Test;
 

src/test/java/org/apache/commons/collections4/bloomfilter/EnhancedDoubleHasherTest.java

@@ -18,6 +18,7 @@ package org.apache.commons.collections4.bloomfilter;
 
 import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.junit.jupiter.api.Assertions.assertThrows;
+
 import org.junit.jupiter.api.Test;
 
 /**

src/test/java/org/apache/commons/collections4/bloomfilter/ShapeTest.java

@@ -16,13 +16,12 @@
  */
 package org.apache.commons.collections4.bloomfilter;
 
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertNotEquals;
 import static org.junit.jupiter.api.Assertions.assertThrows;
 
 import java.util.Arrays;
 
-import static org.junit.jupiter.api.Assertions.assertEquals;
-import static org.junit.jupiter.api.Assertions.assertNotEquals;
-
 import org.junit.jupiter.api.Assertions;
 import org.junit.jupiter.api.Test;
 import org.junit.jupiter.params.ParameterizedTest;

src/test/java/org/apache/commons/collections4/collection/AbstractCollectionTest.java

@@ -39,6 +39,7 @@ import java.util.Objects;
 import java.util.function.Predicate;
 
 import org.apache.commons.collections4.AbstractObjectTest;
+import org.apache.commons.lang3.ArrayUtils;
 import org.junit.jupiter.api.Assertions;
 import org.junit.jupiter.api.Test;
 
@@ -1120,7 +1121,7 @@ public abstract class AbstractCollectionTest<E> extends AbstractObjectTest {
                 "toArray(null) should raise NPE");
         verify();
 
-        array = getCollection().toArray(new Object[0]);
+        array = getCollection().toArray(ArrayUtils.EMPTY_OBJECT_ARRAY);
         a = getCollection().toArray();
 
         if ((getIterationBehaviour() & UNORDERED) != 0) {

src/test/java/org/apache/commons/collections4/collection/PredicatedCollectionBuilderTest.java

@@ -16,6 +16,10 @@
  */
 package org.apache.commons.collections4.collection;
 
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
 import java.util.Arrays;
 import java.util.Collection;
 import java.util.List;
@@ -26,10 +30,6 @@ import org.apache.commons.collections4.Bag;
 import org.apache.commons.collections4.Predicate;
 import org.junit.jupiter.api.Test;
 
-import static org.junit.jupiter.api.Assertions.assertEquals;
-import static org.junit.jupiter.api.Assertions.assertThrows;
-import static org.junit.jupiter.api.Assertions.assertTrue;
-
 /**
  * Tests the PredicatedCollection.Builder class.
  *

src/test/java/org/apache/commons/collections4/comparators/BooleanComparatorTest.java

@@ -16,6 +16,10 @@
  */
 package org.apache.commons.collections4.comparators;
 
+import static org.junit.jupiter.api.Assertions.assertAll;
+import static org.junit.jupiter.api.Assertions.assertNotEquals;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Comparator;
@@ -23,10 +27,6 @@ import java.util.List;
 
 import org.junit.jupiter.api.Test;
 
-import static org.junit.jupiter.api.Assertions.assertAll;
-import static org.junit.jupiter.api.Assertions.assertNotEquals;
-import static org.junit.jupiter.api.Assertions.assertThrows;
-
 /**
  * Tests for {@link BooleanComparator}.
  */

src/test/java/org/apache/commons/collections4/comparators/FixedOrderComparatorTest.java

@@ -24,6 +24,7 @@ import java.util.LinkedList;
 import java.util.List;
 import java.util.Random;
 
+import org.apache.commons.lang3.ArrayUtils;
 import org.junit.jupiter.api.Test;
 
 /**
@@ -170,7 +171,7 @@ public class FixedOrderComparatorTest extends AbstractComparatorTest<String> {
         assertEquals(FixedOrderComparator.UnknownObjectBehavior.BEFORE, comparator.getUnknownObjectBehavior());
         LinkedList<String> keys = new LinkedList<>(Arrays.asList(topCities));
         keys.addFirst("Minneapolis");
-        assertComparatorYieldsOrder(keys.toArray(new String[0]), comparator);
+        assertComparatorYieldsOrder(keys.toArray(ArrayUtils.EMPTY_STRING_ARRAY), comparator);
 
         assertEquals(-1, comparator.compare("Minneapolis", "New York"));
         assertEquals( 1, comparator.compare("New York", "Minneapolis"));
@@ -180,7 +181,7 @@ public class FixedOrderComparatorTest extends AbstractComparatorTest<String> {
         comparator.setUnknownObjectBehavior(FixedOrderComparator.UnknownObjectBehavior.AFTER);
         keys = new LinkedList<>(Arrays.asList(topCities));
         keys.add("Minneapolis");
-        assertComparatorYieldsOrder(keys.toArray(new String[0]), comparator);
+        assertComparatorYieldsOrder(keys.toArray(ArrayUtils.EMPTY_STRING_ARRAY), comparator);
 
         assertEquals( 1, comparator.compare("Minneapolis", "New York"));
         assertEquals(-1, comparator.compare("New York", "Minneapolis"));

src/test/java/org/apache/commons/collections4/functors/AbstractAnyAllOnePredicateTest.java

@@ -16,15 +16,15 @@
  */
 package org.apache.commons.collections4.functors;
 
-import org.apache.commons.collections4.Predicate;
-
 import static org.junit.jupiter.api.Assertions.assertFalse;
 import static org.junit.jupiter.api.Assertions.assertSame;
 import static org.junit.jupiter.api.Assertions.assertTrue;
-import org.junit.jupiter.api.Test;
 
 import java.util.Collections;
 
+import org.apache.commons.collections4.Predicate;
+import org.junit.jupiter.api.Test;
+
 /**
  * Base class for tests of AnyPredicate, AllPredicate, and OnePredicate.
  *

src/test/java/org/apache/commons/collections4/functors/AbstractClosureTest.java

@@ -16,11 +16,11 @@
  */
 package org.apache.commons.collections4.functors;
 
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+
 import org.apache.commons.collections4.Closure;
 import org.junit.jupiter.api.Test;
 
-import static org.junit.jupiter.api.Assertions.assertNotNull;
-
 public abstract class AbstractClosureTest {
 
     @Test

src/test/java/org/apache/commons/collections4/functors/AbstractCompositePredicateTest.java

@@ -16,6 +16,8 @@
  */
 package org.apache.commons.collections4.functors;
 
+import static org.junit.jupiter.api.Assertions.assertThrows;
+
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.Collections;
@@ -25,8 +27,6 @@ import org.apache.commons.collections4.Predicate;
 import org.junit.jupiter.api.Assertions;
 import org.junit.jupiter.api.Test;
 
-import static org.junit.jupiter.api.Assertions.assertThrows;
-
 /**
  * Base class for tests of composite predicates.
  *

src/test/java/org/apache/commons/collections4/functors/AbstractMockPredicateTest.java

@@ -16,15 +16,16 @@
  */
 package org.apache.commons.collections4.functors;
 
+import static org.easymock.EasyMock.replay;
+import static org.easymock.EasyMock.verify;
+
 import java.util.ArrayList;
 import java.util.List;
 
-import static org.easymock.EasyMock.verify;
-import static org.easymock.EasyMock.replay;
-import org.junit.jupiter.api.BeforeEach;
-import org.junit.jupiter.api.AfterEach;
 import org.apache.commons.collections4.Predicate;
 import org.easymock.EasyMock;
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.BeforeEach;
 
 /**
  * Base class for tests of predicates which delegate to other predicates when evaluating an object.  This class

src/test/java/org/apache/commons/collections4/functors/AllPredicateTest.java

@@ -16,16 +16,16 @@
  */
 package org.apache.commons.collections4.functors;
 
-import org.apache.commons.collections4.Predicate;
-
 import static org.apache.commons.collections4.functors.AllPredicate.allPredicate;
 import static org.junit.jupiter.api.Assertions.assertFalse;
 import static org.junit.jupiter.api.Assertions.assertTrue;
-import org.junit.jupiter.api.Test;
 
 import java.util.Collection;
 import java.util.Collections;
 
+import org.apache.commons.collections4.Predicate;
+import org.junit.jupiter.api.Test;
+
 /**
  * Tests the org.apache.commons.collections.functors.AllPredicate class.
  *

src/test/java/org/apache/commons/collections4/functors/CatchAndRethrowClosureTest.java

@@ -16,6 +16,10 @@
  */
 package org.apache.commons.collections4.functors;
 
+import static org.junit.jupiter.api.Assertions.assertThrows;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+import static org.junit.jupiter.api.DynamicTest.dynamicTest;
+
 import java.io.IOException;
 import java.util.Arrays;
 import java.util.Collection;
@@ -25,10 +29,6 @@ import org.apache.commons.collections4.FunctorException;
 import org.junit.jupiter.api.DynamicTest;
 import org.junit.jupiter.api.TestFactory;
 
-import static org.junit.jupiter.api.Assertions.assertThrows;
-import static org.junit.jupiter.api.Assertions.assertTrue;
-import static org.junit.jupiter.api.DynamicTest.dynamicTest;
-
 public class CatchAndRethrowClosureTest extends AbstractClosureTest {
 
     private static <T> Closure<T> generateIOExceptionClosure() {

src/test/java/org/apache/commons/collections4/functors/ComparatorPredicateTest.java

@@ -16,11 +16,12 @@
  */
 package org.apache.commons.collections4.functors;
 
-import static org.apache.commons.collections4.functors.ComparatorPredicate.*;
+import static org.apache.commons.collections4.functors.ComparatorPredicate.comparatorPredicate;
 
 import java.util.Comparator;
 
 import org.apache.commons.collections4.Predicate;
+import org.apache.commons.collections4.functors.ComparatorPredicate.Criterion;
 import org.junit.jupiter.api.Test;
 
 

src/test/java/org/apache/commons/collections4/iterators/ArrayIteratorTest.java

@@ -16,13 +16,13 @@
  */
 package org.apache.commons.collections4.iterators;
 
+import static org.junit.jupiter.api.Assertions.assertThrows;
+
 import java.util.Iterator;
 import java.util.NoSuchElementException;
 
 import org.junit.jupiter.api.Test;
 
-import static org.junit.jupiter.api.Assertions.assertThrows;
-
 /**
  * Tests the ArrayIterator to ensure that the next() method will actually
  * perform the iteration rather than the hasNext() method.

src/test/java/org/apache/commons/collections4/iterators/ArrayListIteratorTest.java

@@ -16,14 +16,14 @@
  */
 package org.apache.commons.collections4.iterators;
 
+import static org.junit.jupiter.api.Assertions.assertArrayEquals;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+
 import java.util.ListIterator;
 import java.util.NoSuchElementException;
 
 import org.junit.jupiter.api.Test;
 
-import static org.junit.jupiter.api.Assertions.assertArrayEquals;
-import static org.junit.jupiter.api.Assertions.assertThrows;
-
 /**
  * Test the ArrayListIterator class.
  */

src/test/java/org/apache/commons/collections4/iterators/FilterIteratorTest.java

@@ -28,6 +28,7 @@ import java.util.NoSuchElementException;
 
 import org.apache.commons.collections4.Predicate;
 import org.apache.commons.collections4.functors.NotNullPredicate;
+import org.apache.commons.lang3.ArrayUtils;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 
@@ -105,7 +106,7 @@ public class FilterIteratorTest<E> extends AbstractIteratorTest<E> {
 
     @Test
     public void testReturnValues() {
-        verifyElementsInPredicate(new String[0]);
+        verifyElementsInPredicate(ArrayUtils.EMPTY_STRING_ARRAY);
         verifyElementsInPredicate(new String[] { "a" });
         verifyElementsInPredicate(new String[] { "b" });
         verifyElementsInPredicate(new String[] { "c" });

src/test/java/org/apache/commons/collections4/iterators/FilterListIteratorTest.java

@@ -16,6 +16,10 @@
  */
 package org.apache.commons.collections4.iterators;
 
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.List;
@@ -29,10 +33,6 @@ import org.junit.jupiter.api.AfterEach;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 
-import static org.junit.jupiter.api.Assertions.assertEquals;
-import static org.junit.jupiter.api.Assertions.assertFalse;
-import static org.junit.jupiter.api.Assertions.assertTrue;
-
 /**
  * Tests the FilterListIterator class.
  *

src/test/java/org/apache/commons/collections4/iterators/IteratorEnumerationTest.java

@@ -16,17 +16,17 @@
  */
 package org.apache.commons.collections4.iterators;
 
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
 import java.util.Arrays;
 import java.util.Iterator;
 import java.util.NoSuchElementException;
 
 import org.junit.jupiter.api.Test;
 
-import static org.junit.jupiter.api.Assertions.assertEquals;
-import static org.junit.jupiter.api.Assertions.assertFalse;
-import static org.junit.jupiter.api.Assertions.assertThrows;
-import static org.junit.jupiter.api.Assertions.assertTrue;
-
 /**
  * Tests the IteratorEnumeration.
  */

src/test/java/org/apache/commons/collections4/iterators/ListIteratorWrapper2Test.java

@@ -16,6 +16,8 @@
  */
 package org.apache.commons.collections4.iterators;
 
+import static org.junit.jupiter.api.Assertions.assertThrows;
+
 import java.util.ArrayList;
 import java.util.List;
 import java.util.ListIterator;
@@ -25,8 +27,6 @@ import org.apache.commons.collections4.ResettableListIterator;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 
-import static org.junit.jupiter.api.Assertions.assertThrows;
-
 /**
  * Tests the ListIteratorWrapper to ensure that it behaves as expected when wrapping a ListIterator.
  */

src/test/java/org/apache/commons/collections4/iterators/LoopingIteratorTest.java

@@ -16,6 +16,11 @@
  */
 package org.apache.commons.collections4.iterators;
 
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.List;
@@ -23,11 +28,6 @@ import java.util.NoSuchElementException;
 
 import org.junit.jupiter.api.Test;
 
-import static org.junit.jupiter.api.Assertions.assertEquals;
-import static org.junit.jupiter.api.Assertions.assertFalse;
-import static org.junit.jupiter.api.Assertions.assertThrows;
-import static org.junit.jupiter.api.Assertions.assertTrue;
-
 /**
  * Tests the LoopingIterator class.
  */

src/test/java/org/apache/commons/collections4/iterators/LoopingListIteratorTest.java

@@ -16,6 +16,12 @@
  */
 package org.apache.commons.collections4.iterators;
 
+import static org.junit.jupiter.api.Assertions.assertAll;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.List;
@@ -23,12 +29,6 @@ import java.util.NoSuchElementException;
 
 import org.junit.jupiter.api.Test;
 
-import static org.junit.jupiter.api.Assertions.assertAll;
-import static org.junit.jupiter.api.Assertions.assertEquals;
-import static org.junit.jupiter.api.Assertions.assertFalse;
-import static org.junit.jupiter.api.Assertions.assertThrows;
-import static org.junit.jupiter.api.Assertions.assertTrue;
-
 /**
  * Tests the LoopingListIterator class.
  */

src/test/java/org/apache/commons/collections4/iterators/NodeListIteratorTest.java

@@ -16,7 +16,9 @@
  */
 package org.apache.commons.collections4.iterators;
 
-import static org.easymock.EasyMock.*;
+import static org.easymock.EasyMock.createMock;
+import static org.easymock.EasyMock.expect;
+import static org.easymock.EasyMock.replay;
 import static org.junit.jupiter.api.Assertions.assertThrows;
 
 import java.util.Iterator;

src/test/java/org/apache/commons/collections4/iterators/ObjectArrayListIteratorTest.java

@@ -16,14 +16,14 @@
  */
 package org.apache.commons.collections4.iterators;
 
+import static org.junit.jupiter.api.Assertions.assertArrayEquals;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+
 import java.util.ListIterator;
 import java.util.NoSuchElementException;
 
 import org.junit.jupiter.api.Test;
 
-import static org.junit.jupiter.api.Assertions.assertArrayEquals;
-import static org.junit.jupiter.api.Assertions.assertThrows;
-
 /**
  * Tests the ObjectArrayListIterator class.
  */

src/test/java/org/apache/commons/collections4/iterators/UnmodifiableListIteratorTest.java

@@ -16,6 +16,8 @@
  */
 package org.apache.commons.collections4.iterators;
 
+import static org.junit.jupiter.api.Assertions.assertThrows;
+
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Collections;
@@ -26,8 +28,6 @@ import org.apache.commons.collections4.Unmodifiable;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 
-import static org.junit.jupiter.api.Assertions.assertThrows;
-
 /**
  * Tests the UnmodifiableListIterator.
  */

src/test/java/org/apache/commons/collections4/keyvalue/AbstractMapEntryTest.java

@@ -16,17 +16,17 @@
  */
 package org.apache.commons.collections4.keyvalue;
 
-import java.util.HashMap;
-import java.util.Map;
-
-import org.junit.jupiter.api.Test;
-
 import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.junit.jupiter.api.Assertions.assertNull;
 import static org.junit.jupiter.api.Assertions.assertSame;
 import static org.junit.jupiter.api.Assertions.assertThrows;
 import static org.junit.jupiter.api.Assertions.assertTrue;
 
+import java.util.HashMap;
+import java.util.Map;
+
+import org.junit.jupiter.api.Test;
+
 /**
  * Abstract tests that can be extended to test any Map.Entry implementation.
  * Subclasses must implement {@link #makeMapEntry(Object, Object)} to return

src/test/java/org/apache/commons/collections4/keyvalue/DefaultKeyValueTest.java

@@ -16,17 +16,16 @@
  */
 package org.apache.commons.collections4.keyvalue;
 
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertNull;
+import static org.junit.jupiter.api.Assertions.assertSame;
 import static org.junit.jupiter.api.Assertions.assertThrows;
-
-import org.junit.jupiter.api.Test;
+import static org.junit.jupiter.api.Assertions.assertTrue;
 
 import java.util.HashMap;
 import java.util.Map;
 
-import static org.junit.jupiter.api.Assertions.assertEquals;
-import static org.junit.jupiter.api.Assertions.assertNull;
-import static org.junit.jupiter.api.Assertions.assertSame;
-import static org.junit.jupiter.api.Assertions.assertTrue;
+import org.junit.jupiter.api.Test;
 
 /**
  * Test the DefaultKeyValue class.

src/test/java/org/apache/commons/collections4/keyvalue/DefaultMapEntryTest.java

@@ -16,13 +16,13 @@
  */
 package org.apache.commons.collections4.keyvalue;
 
+import static org.junit.jupiter.api.Assertions.assertSame;
+
 import java.util.Map;
 
 import org.apache.commons.collections4.KeyValue;
 import org.junit.jupiter.api.Test;
 
-import static org.junit.jupiter.api.Assertions.assertSame;
-
 /**
  * Test the DefaultMapEntry class.
  *

src/test/java/org/apache/commons/collections4/keyvalue/MultiKeyTest.java

@@ -16,9 +16,15 @@
  */
 package org.apache.commons.collections4.keyvalue;
 
-import org.junit.jupiter.api.DynamicTest;
-import org.junit.jupiter.api.Test;
-import org.junit.jupiter.api.TestFactory;
+import static org.junit.jupiter.api.Assertions.assertArrayEquals;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertNotEquals;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+import static org.junit.jupiter.api.Assertions.assertNotSame;
+import static org.junit.jupiter.api.Assertions.assertSame;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+import static org.junit.jupiter.api.DynamicTest.dynamicTest;
 
 import java.io.ByteArrayInputStream;
 import java.io.ByteArrayOutputStream;
@@ -31,15 +37,9 @@ import java.util.Collection;
 import java.util.HashMap;
 import java.util.Map;
 
-import static org.junit.jupiter.api.Assertions.assertArrayEquals;
-import static org.junit.jupiter.api.Assertions.assertEquals;
-import static org.junit.jupiter.api.Assertions.assertNotEquals;
-import static org.junit.jupiter.api.Assertions.assertNotNull;
-import static org.junit.jupiter.api.Assertions.assertNotSame;
-import static org.junit.jupiter.api.Assertions.assertSame;
-import static org.junit.jupiter.api.Assertions.assertThrows;
-import static org.junit.jupiter.api.Assertions.assertTrue;
-import static org.junit.jupiter.api.DynamicTest.dynamicTest;
+import org.junit.jupiter.api.DynamicTest;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.TestFactory;
 
 /**
  * Unit tests for {@link org.apache.commons.collections4.keyvalue.MultiKey}.

src/test/java/org/apache/commons/collections4/keyvalue/TiedMapEntryTest.java

@@ -16,12 +16,12 @@
  */
 package org.apache.commons.collections4.keyvalue;
 
-import org.junit.jupiter.api.Test;
+import static org.junit.jupiter.api.Assertions.assertSame;
 
 import java.util.HashMap;
 import java.util.Map;
 
-import static org.junit.jupiter.api.Assertions.assertSame;
+import org.junit.jupiter.api.Test;
 
 /**
  * Test the TiedMapEntry class.

src/test/java/org/apache/commons/collections4/keyvalue/UnmodifiableMapEntryTest.java

@@ -16,16 +16,16 @@
  */
 package org.apache.commons.collections4.keyvalue;
 
+import static org.junit.jupiter.api.Assertions.assertSame;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
 import java.util.Map;
 
 import org.apache.commons.collections4.KeyValue;
 import org.apache.commons.collections4.Unmodifiable;
 import org.junit.jupiter.api.Test;
 
-import static org.junit.jupiter.api.Assertions.assertSame;
-import static org.junit.jupiter.api.Assertions.assertThrows;
-import static org.junit.jupiter.api.Assertions.assertTrue;
-
 /**
  * Test the UnmodifiableMapEntry class.
  *

src/test/java/org/apache/commons/collections4/list/Collections701Test.java

@@ -21,8 +21,8 @@ import java.util.HashSet;
 import java.util.List;
 import java.util.Set;
 
-import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.Assertions;
+import org.junit.jupiter.api.Test;
 
 /**
  * Tests for COLLECTIONS-701.

src/test/java/org/apache/commons/collections4/list/CursorableLinkedListTest.java

@@ -29,6 +29,7 @@ import java.util.ListIterator;
 import java.util.NoSuchElementException;
 
 import org.apache.commons.collections4.BulkTest;
+import org.apache.commons.lang3.ArrayUtils;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 
@@ -1390,7 +1391,7 @@ public class CursorableLinkedListTest<E> extends AbstractLinkedListTest<E> {
         assertEquals("5", elts[4]);
         assertEquals(5, elts.length);
 
-        final String[] elts2 = list.toArray(new String[0]);
+        final String[] elts2 = list.toArray(ArrayUtils.EMPTY_STRING_ARRAY);
         assertEquals("1", elts2[0]);
         assertEquals("2", elts2[1]);
         assertEquals("3", elts2[2]);
@@ -1513,7 +1514,7 @@ public class CursorableLinkedListTest<E> extends AbstractLinkedListTest<E> {
             list.add(prefix + bulk + element);
             list.add(prefix + bulk + bulk + element);
         }
-        return list.toArray(new String[0]);
+        return list.toArray(ArrayUtils.EMPTY_STRING_ARRAY);
     }
 
     @Override

src/test/java/org/apache/commons/collections4/list/GrowthListTest.java

@@ -26,8 +26,8 @@ import java.util.Arrays;
 import java.util.Collection;
 import java.util.List;
 
-import org.junit.jupiter.api.function.Executable;
 import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.function.Executable;
 
 /**
  * Extension of {@link AbstractListTest} for exercising the {@link GrowthList}.

src/test/java/org/apache/commons/collections4/list/LazyListTest.java

@@ -16,16 +16,16 @@
  */
 package org.apache.commons.collections4.list;
 
-import org.apache.commons.collections4.AbstractObjectTest;
-import org.apache.commons.collections4.Factory;
-import org.apache.commons.collections4.Transformer;
-import org.junit.jupiter.api.Test;
-
 import java.time.LocalDateTime;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.List;
 
+import org.apache.commons.collections4.AbstractObjectTest;
+import org.apache.commons.collections4.Factory;
+import org.apache.commons.collections4.Transformer;
+import org.junit.jupiter.api.Test;
+
 public class LazyListTest extends AbstractObjectTest {
 
     public LazyListTest() {

src/test/java/org/apache/commons/collections4/list/SetUniqueListTest.java

@@ -16,13 +16,21 @@
  */
 package org.apache.commons.collections4.list;
 
+import static org.junit.jupiter.api.Assertions.assertThrows;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collection;
+import java.util.HashSet;
+import java.util.LinkedList;
+import java.util.List;
+import java.util.ListIterator;
+import java.util.Set;
+import java.util.TreeSet;
+
 import org.apache.commons.collections4.set.UnmodifiableSet;
 import org.junit.jupiter.api.Test;
 
-import java.util.*;
-
-import static org.junit.jupiter.api.Assertions.assertThrows;
-
 /**
  * JUnit tests.
  *

src/test/java/org/apache/commons/collections4/map/CompositeMapTest.java

@@ -18,9 +18,9 @@ package org.apache.commons.collections4.map;
 
 import static org.junit.jupiter.api.Assertions.assertThrows;
 
-import java.util.Map;
-import java.util.HashMap;
 import java.util.Collection;
+import java.util.HashMap;
+import java.util.Map;
 
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;

src/test/java/org/apache/commons/collections4/map/EmptyMapMutator.java

@@ -16,8 +16,8 @@
  */
 package org.apache.commons.collections4.map;
 
-import java.util.Map;
 import java.util.Collection;
+import java.util.Map;
 
 /**
  * This class is used in TestCompositeMap. When testing serialization,

src/test/java/org/apache/commons/collections4/map/LazySortedMapTest.java

@@ -16,7 +16,7 @@
  */
 package org.apache.commons.collections4.map;
 
-import static org.apache.commons.collections4.map.LazySortedMap.*;
+import static org.apache.commons.collections4.map.LazySortedMap.lazySortedMap;
 import static org.junit.jupiter.api.Assertions.assertAll;
 import static org.junit.jupiter.api.Assertions.assertThrows;
 

src/test/java/org/apache/commons/collections4/multimap/ArrayListValuedHashMapTest.java

@@ -16,12 +16,12 @@
  */
 package org.apache.commons.collections4.multimap;
 
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.HashMap;
 import java.util.List;
 import java.util.ListIterator;
 import java.util.Map;
-import java.util.HashMap;
-import java.util.Arrays;
-import java.util.ArrayList;
 
 import org.apache.commons.collections4.BulkTest;
 import org.apache.commons.collections4.ListValuedMap;

src/test/java/org/apache/commons/collections4/multimap/UnmodifiableMultiValuedMapTest.java

@@ -18,13 +18,13 @@ package org.apache.commons.collections4.multimap;
 
 import static org.junit.jupiter.api.Assertions.assertThrows;
 
-import java.util.Set;
-import java.util.Map;
-import java.util.Map.Entry;
-import java.util.HashMap;
 import java.util.Arrays;
 import java.util.Collection;
+import java.util.HashMap;
 import java.util.Iterator;
+import java.util.Map;
+import java.util.Map.Entry;
+import java.util.Set;
 
 import org.apache.commons.collections4.BulkTest;
 import org.apache.commons.collections4.MapIterator;

src/test/java/org/apache/commons/collections4/multiset/AbstractMultiSetTest.java

@@ -34,6 +34,7 @@ import org.apache.commons.collections4.BulkTest;
 import org.apache.commons.collections4.MultiSet;
 import org.apache.commons.collections4.collection.AbstractCollectionTest;
 import org.apache.commons.collections4.set.AbstractSetTest;
+import org.apache.commons.lang3.ArrayUtils;
 import org.junit.jupiter.api.Test;
 
 /**
@@ -517,7 +518,7 @@ public abstract class AbstractMultiSetTest<T> extends AbstractCollectionTest<T>
         multiset.add((T) "B");
         multiset.add((T) "B");
         multiset.add((T) "C");
-        final String[] array = multiset.toArray(new String[0]);
+        final String[] array = multiset.toArray(ArrayUtils.EMPTY_STRING_ARRAY);
         int a = 0, b = 0, c = 0;
         for (final String element : array) {
             a += element.equals("A") ? 1 : 0;

src/test/java/org/apache/commons/collections4/properties/AbstractPropertiesFactoryTest.java

@@ -16,6 +16,8 @@
  */
 package org.apache.commons.collections4.properties;
 
+import static org.junit.jupiter.params.provider.Arguments.arguments;
+
 import java.io.BufferedReader;
 import java.io.FileInputStream;
 import java.nio.file.Files;
@@ -24,15 +26,13 @@ import java.util.Properties;
 import java.util.stream.Stream;
 
 import org.apache.commons.collections4.BulkTest;
-import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.Assertions;
 import org.junit.jupiter.api.Assumptions;
+import org.junit.jupiter.api.Test;
 import org.junit.jupiter.params.ParameterizedTest;
 import org.junit.jupiter.params.provider.Arguments;
 import org.junit.jupiter.params.provider.MethodSource;
 
-import static org.junit.jupiter.params.provider.Arguments.arguments;
-
 public abstract class AbstractPropertiesFactoryTest<T extends Properties> {
 
     public static Stream<Arguments> getParameters() {

src/test/java/org/apache/commons/collections4/properties/EmptyPropertiesTest.java

@@ -35,6 +35,7 @@ import java.io.UnsupportedEncodingException;
 import java.nio.charset.StandardCharsets;
 import java.util.HashMap;
 import java.util.Properties;
+
 import org.apache.commons.io.input.NullReader;
 import org.apache.commons.lang3.ArrayUtils;
 import org.junit.jupiter.api.Test;

src/test/java/org/apache/commons/collections4/properties/PropertiesFactoryTest.java

@@ -19,8 +19,8 @@ package org.apache.commons.collections4.properties;
 
 import java.util.Properties;
 
-import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.Assertions;
+import org.junit.jupiter.api.Test;
 
 public class PropertiesFactoryTest extends AbstractPropertiesFactoryTest<Properties> {
 

src/test/java/org/apache/commons/collections4/properties/SortedPropertiesTest.java

@@ -20,8 +20,8 @@ import java.util.Enumeration;
 import java.util.Iterator;
 import java.util.Map;
 
-import org.junit.jupiter.api.Test;
 import org.junit.jupiter.api.Assertions;
+import org.junit.jupiter.api.Test;
 
 public class SortedPropertiesTest {
 

src/test/java/org/apache/commons/collections4/sequence/SequencesComparatorTest.java

@@ -16,6 +16,9 @@
  */
 package org.apache.commons.collections4.sequence;
 
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.List;
@@ -25,9 +28,6 @@ import org.junit.jupiter.api.AfterEach;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
 
-import static org.junit.jupiter.api.Assertions.assertEquals;
-import static org.junit.jupiter.api.Assertions.assertTrue;
-
 public class SequencesComparatorTest {
 
     private List<String> before;

src/test/java/org/apache/commons/collections4/set/TransformedNavigableSetTest.java

@@ -19,8 +19,8 @@ package org.apache.commons.collections4.set;
 import java.util.Arrays;
 import java.util.Collections;
 import java.util.NavigableSet;
-import java.util.TreeSet;
 import java.util.Set;
+import java.util.TreeSet;
 
 import org.apache.commons.collections4.BulkTest;
 import org.apache.commons.collections4.Transformer;

src/test/java/org/apache/commons/collections4/set/TransformedSortedSetTest.java

@@ -18,9 +18,9 @@ package org.apache.commons.collections4.set;
 
 import java.util.Arrays;
 import java.util.Collections;
-import java.util.TreeSet;
 import java.util.Set;
 import java.util.SortedSet;
+import java.util.TreeSet;
 
 import org.apache.commons.collections4.BulkTest;
 import org.apache.commons.collections4.Transformer;

src/test/java/org/apache/commons/collections4/set/UnmodifiableNavigableSetTest.java

@@ -16,6 +16,8 @@
  */
 package org.apache.commons.collections4.set;
 
+import static org.junit.jupiter.api.Assertions.assertThrows;
+
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Comparator;
@@ -26,8 +28,6 @@ import java.util.TreeSet;
 import org.apache.commons.collections4.BulkTest;
 import org.junit.jupiter.api.Test;
 
-import static org.junit.jupiter.api.Assertions.assertThrows;
-
 /**
  * Extension of {@link AbstractNavigableSetTest} for exercising the
  * {@link UnmodifiableNavigableSet} implementation.