public final HiveParser_SelectClauseParser.window_defn_return window_defn() throws RecognitionException {
		HiveParser_SelectClauseParser.window_defn_return retval = new HiveParser_SelectClauseParser.window_defn_return();
		retval.start = input.LT(1);

		CommonTree root_0 = null;

		Token Identifier92=null;
		Token KW_AS93=null;
		ParserRuleReturnScope window_specification94 =null;

		CommonTree Identifier92_tree=null;
		CommonTree KW_AS93_tree=null;
		RewriteRuleTokenStream stream_KW_AS=new RewriteRuleTokenStream(adaptor,"token KW_AS");
		RewriteRuleTokenStream stream_Identifier=new RewriteRuleTokenStream(adaptor,"token Identifier");
		RewriteRuleSubtreeStream stream_window_specification=new RewriteRuleSubtreeStream(adaptor,"rule window_specification");

		 gParent.msgs.push("window_defn"); 
		try {
			// SelectClauseParser.g:250:3: ( Identifier KW_AS window_specification -> ^( TOK_WINDOWDEF Identifier window_specification ) )
			// SelectClauseParser.g:251:3: Identifier KW_AS window_specification
			{
			Identifier92=(Token)match(input,Identifier,FOLLOW_Identifier_in_window_defn1701);  
			stream_Identifier.add(Identifier92);

			KW_AS93=(Token)match(input,KW_AS,FOLLOW_KW_AS_in_window_defn1703);  
			stream_KW_AS.add(KW_AS93);

			pushFollow(FOLLOW_window_specification_in_window_defn1705);
			window_specification94=window_specification();
			state._fsp--;

			stream_window_specification.add(window_specification94.getTree());
			// AST REWRITE
			// elements: window_specification, Identifier
			// token labels: 
			// rule labels: retval
			// token list labels: 
			// rule list labels: 
			// wildcard labels: 
			retval.tree = root_0;
			RewriteRuleSubtreeStream stream_retval=new RewriteRuleSubtreeStream(adaptor,"rule retval",retval!=null?retval.getTree():null);

			root_0 = (CommonTree)adaptor.nil();
			// 251:41: -> ^( TOK_WINDOWDEF Identifier window_specification )
			{
				// SelectClauseParser.g:251:44: ^( TOK_WINDOWDEF Identifier window_specification )
				{
				CommonTree root_1 = (CommonTree)adaptor.nil();
				root_1 = (CommonTree)adaptor.becomeRoot((CommonTree)adaptor.create(TOK_WINDOWDEF, "TOK_WINDOWDEF"), root_1);
				adaptor.addChild(root_1, stream_Identifier.nextNode());
				adaptor.addChild(root_1, stream_window_specification.nextTree());
				adaptor.addChild(root_0, root_1);
				}

			}


			retval.tree = root_0;

			}

			retval.stop = input.LT(-1);

			retval.tree = (CommonTree)adaptor.rulePostProcessing(root_0);
			adaptor.setTokenBoundaries(retval.tree, retval.start, retval.stop);

			 gParent.msgs.pop(); 
		}

		catch (RecognitionException e) {
		  throw e;
		}

		finally {
			// do for sure before leaving
		}
		return retval;
	}