diff --git a/src/parser/aast/api/AASTNode.php b/src/parser/aast/api/AASTNode.php
--- a/src/parser/aast/api/AASTNode.php
+++ b/src/parser/aast/api/AASTNode.php
@@ -34,23 +34,23 @@
     $this->tree = $tree;
   }
 
-  public function getParentNode() {
+  public final function getParentNode() {
     return $this->parentNode;
   }
 
-  public function getID() {
+  public final function getID() {
     return $this->id;
   }
 
-  public function getTypeID() {
+  public final function getTypeID() {
     return $this->typeID;
   }
 
-  public function getTree() {
+  public final function getTree() {
     return $this->tree;
   }
 
-  public function getTypeName() {
+  public final function getTypeName() {
     if (empty($this->typeName)) {
       $this->typeName =
         $this->tree->getNodeTypeNameFromTypeID($this->getTypeID());
@@ -58,7 +58,7 @@
     return $this->typeName;
   }
 
-  public function getChildren() {
+  public final function getChildren() {
     return $this->children;
   }
 
@@ -250,11 +250,11 @@
     return pht('a node of type %s: "%s"', $this->getTypeName(), $concrete);
   }
 
-  protected function getTypeIDFromTypeName($type_name) {
+  protected final function getTypeIDFromTypeName($type_name) {
     return $this->tree->getNodeTypeIDFromTypeName($type_name);
   }
 
-  public function getOffset() {
+  public final function getOffset() {
     $stream = $this->tree->getRawTokenStream();
     if (empty($stream[$this->l])) {
       return null;
@@ -262,7 +262,7 @@
     return $stream[$this->l]->getOffset();
   }
 
-  public function getLength() {
+  public final function getLength() {
     $stream = $this->tree->getRawTokenStream();
     if (empty($stream[$this->r])) {
       return null;
@@ -288,11 +288,11 @@
     return array($before, $after);
   }
 
-  public function getLineNumber() {
+  public final function getLineNumber() {
     return idx($this->tree->getOffsetToLineNumberMap(), $this->getOffset());
   }
 
-  public function getEndLineNumber() {
+  public final function getEndLineNumber() {
     return idx(
       $this->tree->getOffsetToLineNumberMap(),
       $this->getOffset() + $this->getLength());
diff --git a/src/parser/aast/api/AASTToken.php b/src/parser/aast/api/AASTToken.php
--- a/src/parser/aast/api/AASTToken.php
+++ b/src/parser/aast/api/AASTToken.php
@@ -17,11 +17,11 @@
     $this->tree = $tree;
   }
 
-  public function getTokenID() {
+  public final function getTokenID() {
     return $this->id;
   }
 
-  public function getTypeID() {
+  public final function getTypeID() {
     return $this->typeID;
   }
 
@@ -32,11 +32,11 @@
     return $this->typeName;
   }
 
-  public function getValue() {
+  public final function getValue() {
     return $this->value;
   }
 
-  public function getOffset() {
+  public final function getOffset() {
     return $this->offset;
   }
 
diff --git a/src/parser/aast/api/AASTTree.php b/src/parser/aast/api/AASTTree.php
--- a/src/parser/aast/api/AASTTree.php
+++ b/src/parser/aast/api/AASTTree.php
@@ -43,28 +43,28 @@
     $this->buildTree(array($tree));
   }
 
-  public function setTreeType($description) {
+  public final function setTreeType($description) {
     $this->treeType = $description;
     return $this;
   }
 
-  public function getTreeType() {
+  public final function getTreeType() {
     return $this->treeType;
   }
 
-  public function setTokenConstants(array $token_map) {
+  public final function setTokenConstants(array $token_map) {
     $this->tokenConstants = $token_map;
     $this->tokenReverseMap = array_flip($token_map);
     return $this;
   }
 
-  public function setNodeConstants(array $node_map) {
+  public final function setNodeConstants(array $node_map) {
     $this->nodeConstants = $node_map;
     $this->nodeReverseMap = array_flip($node_map);
     return $this;
   }
 
-  public function getNodeTypeNameFromTypeID($type_id) {
+  public final function getNodeTypeNameFromTypeID($type_id) {
     if (empty($this->nodeConstants[$type_id])) {
       $tree_type = $this->getTreeType();
       throw new Exception(
@@ -77,7 +77,7 @@
     return $this->nodeConstants[$type_id];
   }
 
-  public function getNodeTypeIDFromTypeName($type_name) {
+  public final function getNodeTypeIDFromTypeName($type_name) {
     if (empty($this->nodeReverseMap[$type_name])) {
       $tree_type = $this->getTreeType();
       throw new Exception(
@@ -89,7 +89,7 @@
     return $this->nodeReverseMap[$type_name];
   }
 
-  public function getTokenTypeNameFromTypeID($type_id) {
+  public final function getTokenTypeNameFromTypeID($type_id) {
     if (empty($this->tokenConstants[$type_id])) {
       $tree_type = $this->getTreeType();
       throw new Exception(
@@ -101,7 +101,7 @@
     return $this->tokenConstants[$type_id];
   }
 
-  public function getTokenTypeIDFromTypeName($type_name) {
+  public final function getTokenTypeIDFromTypeName($type_name) {
     if (empty($this->tokenReverseMap[$type_name])) {
       $tree_type = $this->getTreeType();
       throw new Exception(
@@ -126,7 +126,7 @@
     unset($this->stream);
   }
 
-  public function getRootNode() {
+  public final function getRootNode() {
     return $this->tree[0];
   }
 
@@ -156,7 +156,7 @@
     return $result;
   }
 
-  public function getRawTokenStream() {
+  public final function getRawTokenStream() {
     return $this->stream;
   }
 
diff --git a/src/parser/xhpast/api/XHPASTNode.php b/src/parser/xhpast/api/XHPASTNode.php
--- a/src/parser/xhpast/api/XHPASTNode.php
+++ b/src/parser/xhpast/api/XHPASTNode.php
@@ -230,8 +230,4 @@
     return stripcslashes($out);
   }
 
-  public function getLineNumber() {
-    return idx($this->tree->getOffsetToLineNumberMap(), $this->getOffset());
-  }
-
 }