docs: public final JavaParser.expression_return expression() throws RecognitionException {
  		JavaParser.expression_return retval = new JavaParser.expression_return();
  		retval.start = input.LT(1);
  		int expression_StartIndex = input.index();
  
  		try {
  			if ( state.backtracking>0 && alreadyParsedRule(input, 108) ) { return retval; }
  
  			// src/main/resources/org/drools/compiler/semantics/java/parser/Java.g:1119:5: ( conditionalExpression ( assignmentOperator expression )? )
  			// src/main/resources/org/drools/compiler/semantics/java/parser/Java.g:1119:7: conditionalExpression ( assignmentOperator expression )?
  			{
  			pushFollow(FOLLOW_conditionalExpression_in_expression4875);
  			conditionalExpression();
  			state._fsp--;
  			if (state.failed) return retval;
  			// src/main/resources/org/drools/compiler/semantics/java/parser/Java.g:1119:29: ( assignmentOperator expression )?
  			int alt140=2;
  			alt140 = dfa140.predict(input);
  			switch (alt140) {
  				case 1 :
  					// src/main/resources/org/drools/compiler/semantics/java/parser/Java.g:1119:30: assignmentOperator expression
  					{
  					pushFollow(FOLLOW_assignmentOperator_in_expression4878);
  					assignmentOperator();
  					state._fsp--;
  					if (state.failed) return retval;
  					pushFollow(FOLLOW_expression_in_expression4880);
  					expression();
  					state._fsp--;
  					if (state.failed) return retval;
  					}
  					break;
  
  			}
  
  			}
  
  			retval.stop = input.LT(-1);
  
  		}
  		catch (RecognitionException re) {
  			reportError(re);
  			recover(input,re);
  		}
  		finally {
  			// do for sure before leaving
  			if ( state.backtracking>0 ) { memoize(input, 108, expression_StartIndex); }
  
  		}
  		return retval;
  	}