Custom Spliterator for Structure Modifier

src/main/java/com/comphenix/protocol/reflect/StructureModifier.java

@@ -42,8 +42,10 @@
 import java.util.List;
 import java.util.Map;
 import java.util.Optional;
+import java.util.Spliterator;
 import java.util.function.UnaryOperator;
 import java.util.stream.Collectors;
+import java.util.stream.Stream;
 
 /**
  * Provides list-oriented access to the fields of a Minecraft packet.
@@ -676,4 +678,12 @@ public String toString() {
     public Iterator<StructureModifierIntermediate<T>> iterator() {
         return new StructureModifierIterator<T>(this);
     }
+
+    /**
+	 * {@inheritDoc}
+	 */
+    @Override
+    public Spliterator<StructureModifierIntermediate<T>> spliterator() {
+        return new StructureModifierSpliterator<T>(this);
+    }
 }

src/main/java/com/comphenix/protocol/reflect/StructureModifierSpliterator.java

@@ -0,0 +1,126 @@
+/*
+ *  ProtocolLib - Bukkit server library that allows access to the Minecraft protocol.
+ *  Copyright (C) 2012 Kristian S. Stangeland
+ *
+ *  This program is free software; you can redistribute it and/or modify it under the terms of the
+ *  GNU General Public License as published by the Free Software Foundation; either version 2 of
+ *  the License, or (at your option) any later version.
+ *
+ *  This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY;
+ *  without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ *  See the GNU General Public License for more details.
+ *
+ *  You should have received a copy of the GNU General Public License along with this program;
+ *  if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+ *  02111-1307 USA
+ */
+package com.comphenix.protocol.reflect;
+
+import java.util.Spliterator;
+import java.util.function.Consumer;
+
+/**
+ * Provides {@link Spliterator} access to a {@link StructureModifier}
+ *
+ * @param <T> Type of the fields in the {@link StructureModifier}
+ * @author BradBot_1
+ */
+class StructureModifierSpliterator<T> implements Spliterator<StructureModifierIntermediate<T>> {
+
+    private final StructureModifier<T> structure;
+    private int index;
+    private int bounds;
+
+    /**
+     * @param structure - {@link StructureModifier} to operate on.
+     */
+    StructureModifierSpliterator(final StructureModifier<T> structure) {
+        this(structure, 0, structure.size());
+    }
+
+    /**
+     * @param structure - {@link StructureModifier} to operate on.
+     * @param offset - The offset to start at
+     * @param bounds - The max bound for reading.
+     */
+    StructureModifierSpliterator(final StructureModifier<T> structure, final int offset, final int bounds) {
+        this.structure = structure;
+        this.index = offset;
+        this.bounds = bounds;
+    }
+
+
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    public StructureModifierSpliterator<T> trySplit() {
+        final int remainingElements = this.bounds - this.index;
+        if (remainingElements <= 1) return null; // as spec
+        final int newSplitBounds = bounds;
+        this.bounds -= (remainingElements - (remainingElements % 2)) / 2;
+        return new StructureModifierSpliterator<T>(this.structure, this.bounds, newSplitBounds);
+    }
+
+
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    public boolean tryAdvance(final Consumer<? super StructureModifierIntermediate<T>> action) throws NullPointerException {
+        // as demanded by the spec
+        if (action == null) throw new NullPointerException("The provided consumer is null!");
+        if (this.index >= this.bounds) return false; // hit end of this spliterator
+        final StructureModifierIntermediate<T> intermediate = new StructureModifierIntermediate<T>(this.structure, this.index++);
+        // since it's defined as not null we have to perform this check
+        // yes this makes {@link #estimateSize} inaccurate in some situations, but that's better than a null
+        if (intermediate.get() == null) return tryAdvance(action);
+        action.accept(intermediate);
+        return true;
+    }
+
+
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    public void forEachRemaining(Consumer<? super StructureModifierIntermediate<T>> action) {
+        // as demanded by the spec
+        if (action == null) throw new NullPointerException("The provided consumer is null!");
+        while (this.index < this.bounds) {
+            final StructureModifierIntermediate<T> intermediate = new StructureModifierIntermediate<T>(this.structure, this.index++);
+            // since it's defined as not null we have to perform this check
+            if (intermediate.get() == null) continue;
+            action.accept(intermediate);
+        }
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    public long estimateSize() {
+        return this.bounds - this.index;
+    }
+
+
+    /**
+     * {@inheritDoc}
+     * 
+     * @apiNote Since this implementation is ordered we do not need to perform the check, instead we can just call the method
+     */
+    @Override
+    public long getExactSizeIfKnown() {
+        return this.estimateSize();
+    }
+
+
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    public int characteristics() {
+        return Spliterator.DISTINCT/* | Spliterator.IMMUTABLE*/ | Spliterator.NONNULL | Spliterator.ORDERED | Spliterator.SIZED | Spliterator.SUBSIZED;
+    }
+
+}