Simpler constant definitions.

src/main/java/org/apache/commons/lang3/ArrayUtils.java

@@ -86,7 +86,7 @@ public class ArrayUtils {
     /**
      * An empty immutable {@code Class} array.
      */
-    public static final Class<?>[] EMPTY_CLASS_ARRAY = new Class[0];
+    public static final Class<?>[] EMPTY_CLASS_ARRAY = {};
 
     /**
      * An empty immutable {@code double} array.

src/main/java/org/apache/commons/lang3/tuple/ImmutablePair.java

@@ -44,7 +44,7 @@ public final class ImmutablePair<L, R> extends Pair<L, R> {
      *
      * @since 3.10.
      */
-    public static final ImmutablePair<?, ?>[] EMPTY_ARRAY = new ImmutablePair[0];
+    public static final ImmutablePair<?, ?>[] EMPTY_ARRAY = {};
 
     /**
      * An immutable pair of nulls.

src/main/java/org/apache/commons/lang3/tuple/ImmutableTriple.java

@@ -44,7 +44,7 @@ public final class ImmutableTriple<L, M, R> extends Triple<L, M, R> {
      *
      * @since 3.10.
      */
-    public static final ImmutableTriple<?, ?, ?>[] EMPTY_ARRAY = new ImmutableTriple[0];
+    public static final ImmutableTriple<?, ?, ?>[] EMPTY_ARRAY = {};
 
     /**
      * An immutable triple of nulls.

src/main/java/org/apache/commons/lang3/tuple/MutablePair.java

@@ -39,7 +39,7 @@ public class MutablePair<L, R> extends Pair<L, R> {
      *
      * @since 3.10.
      */
-    public static final MutablePair<?, ?>[] EMPTY_ARRAY = new MutablePair[0];
+    public static final MutablePair<?, ?>[] EMPTY_ARRAY = {};
 
     /** Serialization version */
     private static final long serialVersionUID = 4954918890077093841L;

src/main/java/org/apache/commons/lang3/tuple/MutableTriple.java

@@ -39,7 +39,7 @@ public class MutableTriple<L, M, R> extends Triple<L, M, R> {
      *
      * @since 3.10.
      */
-    public static final MutableTriple<?, ?, ?>[] EMPTY_ARRAY = new MutableTriple[0];
+    public static final MutableTriple<?, ?, ?>[] EMPTY_ARRAY = {};
 
     /** Serialization version */
     private static final long serialVersionUID = 1L;

src/main/java/org/apache/commons/lang3/tuple/Pair.java

@@ -40,27 +40,6 @@
  */
 public abstract class Pair<L, R> implements Map.Entry<L, R>, Comparable<Pair<L, R>>, Serializable {
 
-    private static final class PairAdapter<L, R> extends Pair<L, R> {
-
-        private static final long serialVersionUID = 1L;
-
-        @Override
-        public L getLeft() {
-            return null;
-        }
-
-        @Override
-        public R getRight() {
-            return null;
-        }
-
-        @Override
-        public R setValue(final R value) {
-            return null;
-        }
-
-    }
-
     /** Serialization version */
     private static final long serialVersionUID = 4954918890077093841L;
 
@@ -72,7 +51,7 @@ public R setValue(final R value) {
      *
      * @since 3.10.
      */
-    public static final Pair<?, ?>[] EMPTY_ARRAY = new PairAdapter[0];
+    public static final Pair<?, ?>[] EMPTY_ARRAY = {};
 
     /**
      * Returns the empty array singleton that can be assigned without compiler warning.

src/main/java/org/apache/commons/lang3/tuple/Triple.java

@@ -39,27 +39,6 @@
  */
 public abstract class Triple<L, M, R> implements Comparable<Triple<L, M, R>>, Serializable {
 
-    private static final class TripleAdapter<L, M, R> extends Triple<L, M, R> {
-
-        private static final long serialVersionUID = 1L;
-
-        @Override
-        public L getLeft() {
-            return null;
-        }
-
-        @Override
-        public M getMiddle() {
-            return null;
-        }
-
-        @Override
-        public R getRight() {
-            return null;
-        }
-
-    }
-
     /** Serialization version */
     private static final long serialVersionUID = 1L;
 
@@ -71,7 +50,7 @@ public R getRight() {
      *
      * @since 3.10.
      */
-    public static final Triple<?, ?, ?>[] EMPTY_ARRAY = new TripleAdapter[0];
+    public static final Triple<?, ?, ?>[] EMPTY_ARRAY = {};
 
     /**
      * Returns the empty array singleton that can be assigned without compiler warning.