Reorganize and further unify the new commands.

worldedit-core/src/main/java/com/sk89q/worldedit/function/operation/BlockMapEntryPlacer.java

@@ -25,6 +25,7 @@ import com.sk89q.worldedit.blocks.BaseBlock;
 import com.sk89q.worldedit.extent.Extent;
 
 import java.util.Iterator;
+import java.util.List;
 import java.util.Map;
 
 import static com.google.common.base.Preconditions.checkNotNull;
@@ -64,4 +65,9 @@ public class BlockMapEntryPlacer implements Operation {
     @Override
     public void cancel() {
     }
+
+    @Override
+    public void addStatusMessages(List<String> messages) {
+    }
+
 }

worldedit-core/src/main/java/com/sk89q/worldedit/function/operation/ChangeSetExecutor.java

@@ -25,6 +25,7 @@ import com.sk89q.worldedit.history.changeset.ChangeSet;
 import com.sk89q.worldedit.history.UndoContext;
 
 import java.util.Iterator;
+import java.util.List;
 
 import static com.google.common.base.Preconditions.checkNotNull;
 
@@ -79,6 +80,10 @@ public class ChangeSetExecutor implements Operation {
     public void cancel() {
     }
 
+    @Override
+    public void addStatusMessages(List<String> messages) {
+    }
+
     /**
      * Create a new undo operation.
      *

worldedit-core/src/main/java/com/sk89q/worldedit/function/operation/DelegateOperation.java

@@ -21,6 +21,8 @@ package com.sk89q.worldedit.function.operation;
 
 import com.sk89q.worldedit.WorldEditException;
 
+import java.util.List;
+
 import static com.google.common.base.Preconditions.checkNotNull;
 
 /**
@@ -57,4 +59,10 @@ public class DelegateOperation implements Operation {
         original.cancel();
     }
 
+    @Override
+    public void addStatusMessages(List<String> messages) {
+        original.addStatusMessages(messages);
+        delegate.addStatusMessages(messages);
+    }
+
 }

worldedit-core/src/main/java/com/sk89q/worldedit/function/operation/ForwardExtentCopy.java

@@ -246,4 +246,8 @@ public class ForwardExtentCopy implements Operation {
     public void cancel() {
     }
 
+    @Override
+    public void addStatusMessages(List<String> messages) {
+    }
+
 }

worldedit-core/src/main/java/com/sk89q/worldedit/function/operation/Operation.java

@@ -21,6 +21,8 @@ package com.sk89q.worldedit.function.operation;
 
 import com.sk89q.worldedit.WorldEditException;
 
+import java.util.List;
+
 /**
  * An task that may be split into multiple steps to be run sequentially
  * immediately or at a varying or fixed interval. Operations should attempt
@@ -49,4 +51,12 @@ public interface Operation {
      */
     void cancel();
 
+    /**
+     * Add messages to the provided list that describe the current status
+     * of the operation.
+     *
+     * @param messages The list to add messages to
+     */
+    void addStatusMessages(List<String> messages);
+
 }

worldedit-core/src/main/java/com/sk89q/worldedit/function/operation/OperationQueue.java

@@ -19,11 +19,13 @@
 
 package com.sk89q.worldedit.function.operation;
 
+import com.google.common.collect.Lists;
 import com.sk89q.worldedit.WorldEditException;
 
 import java.util.ArrayDeque;
 import java.util.Collection;
 import java.util.Deque;
+import java.util.List;
 
 import static com.google.common.base.Preconditions.checkNotNull;
 
@@ -32,6 +34,7 @@ import static com.google.common.base.Preconditions.checkNotNull;
  */
 public class OperationQueue implements Operation {
 
+    private final List<Operation> operations = Lists.newArrayList();
     private final Deque<Operation> queue = new ArrayDeque<Operation>();
     private Operation current;
 
@@ -51,6 +54,7 @@ public class OperationQueue implements Operation {
         for (Operation operation : operations) {
             offer(operation);
         }
+        this.operations.addAll(operations);
     }
 
     /**
@@ -100,4 +104,11 @@ public class OperationQueue implements Operation {
         queue.clear();
     }
 
+    @Override
+    public void addStatusMessages(List<String> messages) {
+        for (Operation operation : operations) {
+            operation.addStatusMessages(messages);
+        }
+    }
+
 }