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worldedit-core/src/main/java/com/sk89q/worldedit/extent/MaskingExtent.java

@@ -0,0 +1,72 @@
+/*
+ * WorldEdit, a Minecraft world manipulation toolkit
+ * Copyright (C) sk89q <http://www.sk89q.com>
+ * Copyright (C) WorldEdit team and contributors
+ *
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License as published by the
+ * Free Software Foundation, either version 3 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 Lesser General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package com.sk89q.worldedit.extent;
+
+import com.sk89q.worldedit.Vector;
+import com.sk89q.worldedit.WorldEditException;
+import com.sk89q.worldedit.blocks.BaseBlock;
+import com.sk89q.worldedit.function.mask.Mask;
+
+import static com.google.common.base.Preconditions.checkNotNull;
+
+/**
+ * Requires that all mutating methods pass a given {@link Mask}.
+ */
+public class MaskingExtent extends AbstractDelegateExtent {
+
+    private Mask mask;
+
+    /**
+     * Create a new instance.
+     *
+     * @param extent the extent
+     * @param mask the mask
+     */
+    public MaskingExtent(Extent extent, Mask mask) {
+        super(extent);
+        checkNotNull(mask);
+        this.mask = mask;
+    }
+
+    /**
+     * Get the mask.
+     *
+     * @return the mask
+     */
+    public Mask getMask() {
+        return mask;
+    }
+
+    /**
+     * Set a mask.
+     *
+     * @param mask a mask
+     */
+    public void setMask(Mask mask) {
+        checkNotNull(mask);
+        this.mask = mask;
+    }
+
+    @Override
+    public boolean setBlock(Vector location, BaseBlock block) throws WorldEditException {
+        return mask.test(location) && super.setBlock(location, block);
+    }
+
+}