Build stuff into nodes! They may not do anything, but it's node-tastic!

src/main/java/net/minecraft/commands/builder/ArgumentBuilder.java

@@ -1,6 +1,7 @@
 package net.minecraft.commands.builder;
 
 import com.google.common.collect.Lists;
+import net.minecraft.commands.tree.CommandNode;
 
 import java.util.List;
 
@@ -15,4 +16,6 @@ public abstract class ArgumentBuilder {
     public List<ArgumentBuilder> getArguments() {
         return arguments;
     }
+
+    public abstract CommandNode build();
 }

src/main/java/net/minecraft/commands/builder/CommandBuilder.java

@@ -1,6 +1,7 @@
 package net.minecraft.commands.builder;
 
 import com.google.common.collect.Lists;
+import net.minecraft.commands.tree.LiteralCommandNode;
 
 import java.util.List;
 
@@ -38,4 +39,14 @@ public class CommandBuilder {
     public List<ArgumentBuilder> getArguments() {
         return arguments;
     }
+
+    public LiteralCommandNode build() {
+        LiteralCommandNode result = new LiteralCommandNode(getName());
+
+        for (ArgumentBuilder argument : arguments) {
+            result.addChild(argument.build());
+        }
+
+        return result;
+    }
 }

src/main/java/net/minecraft/commands/builder/RequiredArgumentBuilder.java

@@ -1,6 +1,7 @@
 package net.minecraft.commands.builder;
 
 import net.minecraft.commands.arguments.CommandArgumentType;
+import net.minecraft.commands.tree.ArgumentCommandNode;
 
 public class RequiredArgumentBuilder extends ArgumentBuilder {
     private final String name;
@@ -14,4 +15,22 @@ public class RequiredArgumentBuilder extends ArgumentBuilder {
     public static RequiredArgumentBuilder argument(String name, CommandArgumentType type) {
         return new RequiredArgumentBuilder(name, type);
     }
+
+    public CommandArgumentType getType() {
+        return type;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public ArgumentCommandNode build() {
+        ArgumentCommandNode result = new ArgumentCommandNode(getName(), getType());
+
+        for (ArgumentBuilder argument : getArguments()) {
+            result.addChild(argument.build());
+        }
+
+        return result;
+    }
 }

src/main/java/net/minecraft/commands/tree/ArgumentCommandNode.java

@@ -0,0 +1,21 @@
+package net.minecraft.commands.tree;
+
+import net.minecraft.commands.arguments.CommandArgumentType;
+
+public class ArgumentCommandNode extends CommandNode {
+    private final String name;
+    private final CommandArgumentType type;
+
+    public ArgumentCommandNode(String name, CommandArgumentType type) {
+        this.name = name;
+        this.type = type;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public CommandArgumentType getType() {
+        return type;
+    }
+}

src/main/java/net/minecraft/commands/tree/CommandNode.java

@@ -0,0 +1,17 @@
+package net.minecraft.commands.tree;
+
+import com.google.common.collect.Lists;
+
+import java.util.List;
+
+public abstract class CommandNode {
+    private final List<CommandNode> children = Lists.newArrayList();
+
+    public List<CommandNode> getChildren() {
+        return children;
+    }
+
+    public void addChild(CommandNode node) {
+        children.add(node);
+    }
+}

src/main/java/net/minecraft/commands/tree/LiteralCommandNode.java

@@ -0,0 +1,13 @@
+package net.minecraft.commands.tree;
+
+public class LiteralCommandNode extends CommandNode {
+    private final String literal;
+
+    public LiteralCommandNode(String literal) {
+        this.literal = literal;
+    }
+
+    public String getLiteral() {
+        return literal;
+    }
+}

src/main/java/net/minecraft/commands/tree/package-info.java

@@ -0,0 +1,4 @@
+@ParametersAreNonnullByDefault
+package net.minecraft.commands.tree;
+
+import javax.annotation.ParametersAreNonnullByDefault;

src/main/test/net/minecraft/commands/CommandNodeTest.java

@@ -0,0 +1,8 @@
+package net.minecraft.commands;
+
+import net.minecraft.commands.tree.CommandNode;
+
+public class CommandNodeTest {
+    CommandNode node;
+
+}

src/main/test/net/minecraft/commands/builder/ArgumentBuilderTest.java

@@ -1,5 +1,6 @@
 package net.minecraft.commands.builder;
 
+import net.minecraft.commands.tree.CommandNode;
 import org.junit.Before;
 import org.junit.Test;
 
@@ -14,7 +15,12 @@ public class ArgumentBuilderTest {
 
     @Before
     public void setUp() throws Exception {
-        builder = new ArgumentBuilder() {};
+        builder = new ArgumentBuilder() {
+            @Override
+            public CommandNode build() {
+                return null;
+            }
+        };
     }
 
     @Test

src/main/test/net/minecraft/commands/builder/CommandBuilderTest.java

@@ -1,5 +1,6 @@
 package net.minecraft.commands.builder;
 
+import net.minecraft.commands.tree.LiteralCommandNode;
 import org.junit.Before;
 import org.junit.Test;
 
@@ -7,6 +8,7 @@ import static net.minecraft.commands.arguments.IntegerArgumentType.integer;
 import static net.minecraft.commands.builder.RequiredArgumentBuilder.argument;
 import static org.hamcrest.Matchers.hasItems;
 import static org.hamcrest.Matchers.hasSize;
+import static org.hamcrest.Matchers.is;
 import static org.junit.Assert.assertThat;
 
 public class CommandBuilderTest {
@@ -26,4 +28,20 @@ public class CommandBuilderTest {
         assertThat(builder.getArguments(), hasSize(1));
         assertThat(builder.getArguments(), hasItems((ArgumentBuilder) argument));
     }
+
+    @Test
+    public void testBuild() throws Exception {
+        LiteralCommandNode node = builder.build();
+
+        assertThat(node.getLiteral(), is("foo"));
+    }
+
+    @Test
+    public void testBuildWithChildren() throws Exception {
+        builder.then(argument("bar", integer()));
+        builder.then(argument("baz", integer()));
+        LiteralCommandNode node = builder.build();
+
+        assertThat(node.getChildren(), hasSize(2));
+    }
 }

src/main/test/net/minecraft/commands/builder/RequiredArgumentBuilderTest.java

@@ -0,0 +1,40 @@
+package net.minecraft.commands.builder;
+
+import net.minecraft.commands.arguments.CommandArgumentType;
+import net.minecraft.commands.tree.ArgumentCommandNode;
+import org.junit.Before;
+import org.junit.Test;
+import org.mockito.Mock;
+
+import static net.minecraft.commands.arguments.IntegerArgumentType.integer;
+import static net.minecraft.commands.builder.RequiredArgumentBuilder.argument;
+import static org.hamcrest.Matchers.hasSize;
+import static org.hamcrest.Matchers.is;
+import static org.junit.Assert.assertThat;
+
+public class RequiredArgumentBuilderTest {
+    @Mock CommandArgumentType type;
+    RequiredArgumentBuilder builder;
+
+    @Before
+    public void setUp() throws Exception {
+        builder = argument("foo", type);
+    }
+
+    @Test
+    public void testBuild() throws Exception {
+        ArgumentCommandNode node = builder.build();
+
+        assertThat(node.getName(), is("foo"));
+        assertThat(node.getType(), is(type));
+    }
+
+    @Test
+    public void testBuildWithChildren() throws Exception {
+        builder.then(argument("bar", integer()));
+        builder.then(argument("baz", integer()));
+        ArgumentCommandNode node = builder.build();
+
+        assertThat(node.getChildren(), hasSize(2));
+    }
+}