| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package org.apache.cassandra.cql3; |
| |
| import org.antlr.runtime.ANTLRStringStream; |
| import org.antlr.runtime.CharStream; |
| import org.antlr.runtime.CommonTokenStream; |
| import org.antlr.runtime.RecognitionException; |
| import org.antlr.runtime.TokenStream; |
| import org.apache.cassandra.exceptions.SyntaxException; |
| |
| /** |
| * Helper class to encapsulate common code that calls one of the generated methods in {@code CqlParser}. |
| */ |
| public final class CQLFragmentParser |
| { |
| |
| @FunctionalInterface |
| public interface CQLParserFunction<R> |
| { |
| R parse(CqlParser parser) throws RecognitionException; |
| } |
| |
| public static <R> R parseAny(CQLParserFunction<R> parserFunction, String input, String meaning) |
| { |
| try |
| { |
| return parseAnyUnhandled(parserFunction, input); |
| } |
| catch (RuntimeException re) |
| { |
| throw new SyntaxException(String.format("Failed parsing %s: [%s] reason: %s %s", |
| meaning, |
| input, |
| re.getClass().getSimpleName(), |
| re.getMessage())); |
| } |
| catch (RecognitionException e) |
| { |
| throw new SyntaxException("Invalid or malformed " + meaning + ": " + e.getMessage()); |
| } |
| } |
| |
| /** |
| * Just call a parser method in {@link CqlParser} - does not do any error handling. |
| */ |
| public static <R> R parseAnyUnhandled(CQLParserFunction<R> parserFunction, String input) throws RecognitionException |
| { |
| // Lexer and parser |
| ErrorCollector errorCollector = new ErrorCollector(input); |
| CharStream stream = new ANTLRStringStream(input); |
| CqlLexer lexer = new CqlLexer(stream); |
| lexer.addErrorListener(errorCollector); |
| |
| TokenStream tokenStream = new CommonTokenStream(lexer); |
| CqlParser parser = new CqlParser(tokenStream); |
| parser.addErrorListener(errorCollector); |
| |
| // Parse the query string to a statement instance |
| R r = parserFunction.parse(parser); |
| |
| // The errorCollector has queue up any errors that the lexer and parser may have encountered |
| // along the way, if necessary, we turn the last error into exceptions here. |
| errorCollector.throwFirstSyntaxError(); |
| |
| return r; |
| } |
| } |