com.linkedin.pinot.pql.parsers.Pql2Compiler.java Source code

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Here is the source code for com.linkedin.pinot.pql.parsers.Pql2Compiler.java

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/**
 * Copyright (C) 2014-2016 LinkedIn Corp. (pinot-core@linkedin.com)
 *
 * Licensed 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 com.linkedin.pinot.pql.parsers;

import com.linkedin.pinot.common.request.BrokerRequest;
import com.linkedin.pinot.common.request.transform.TransformExpressionTree;
import com.linkedin.pinot.pql.parsers.pql2.ast.AstNode;

import org.antlr.v4.runtime.ANTLRInputStream;
import org.antlr.v4.runtime.BailErrorStrategy;
import org.antlr.v4.runtime.BaseErrorListener;
import org.antlr.v4.runtime.CharStream;
import org.antlr.v4.runtime.CommonToken;
import org.antlr.v4.runtime.CommonTokenFactory;
import org.antlr.v4.runtime.RecognitionException;
import org.antlr.v4.runtime.Recognizer;
import org.antlr.v4.runtime.TokenStream;
import org.antlr.v4.runtime.UnbufferedTokenStream;
import org.antlr.v4.runtime.misc.NotNull;
import org.antlr.v4.runtime.misc.Nullable;
import org.antlr.v4.runtime.tree.ParseTree;
import org.antlr.v4.runtime.tree.ParseTreeWalker;
import org.apache.commons.lang3.exception.ExceptionUtils;

/**
 * PQL 2 compiler.
 */
public class Pql2Compiler implements AbstractCompiler {
    private static class ErrorListener extends BaseErrorListener {
        @Override
        public void syntaxError(@NotNull Recognizer<?, ?> recognizer, @Nullable Object offendingSymbol, int line,
                int charPositionInLine, @NotNull String msg, @Nullable RecognitionException e) {
            throw new Pql2CompilationException(msg, offendingSymbol, line, charPositionInLine, e);
        }
    }

    private static final ErrorListener ERROR_LISTENER = new ErrorListener();

    @Override
    public BrokerRequest compileToBrokerRequest(String expression) throws Pql2CompilationException {
        try {
            //
            CharStream charStream = new ANTLRInputStream(expression);
            PQL2Lexer lexer = new PQL2Lexer(charStream);
            lexer.setTokenFactory(new CommonTokenFactory(true));
            lexer.removeErrorListeners();
            lexer.addErrorListener(ERROR_LISTENER);
            TokenStream tokenStream = new UnbufferedTokenStream<CommonToken>(lexer);
            PQL2Parser parser = new PQL2Parser(tokenStream);
            parser.setErrorHandler(new BailErrorStrategy());
            parser.removeErrorListeners();
            parser.addErrorListener(ERROR_LISTENER);

            // Parse
            ParseTree parseTree = parser.root();

            ParseTreeWalker walker = new ParseTreeWalker();
            Pql2AstListener listener = new Pql2AstListener(expression);
            walker.walk(listener, parseTree);

            AstNode rootNode = listener.getRootNode();
            BrokerRequest brokerRequest = new BrokerRequest();
            rootNode.updateBrokerRequest(brokerRequest);
            return brokerRequest;
        } catch (Pql2CompilationException e) {
            throw e;
        } catch (Exception e) {
            throw new Pql2CompilationException(ExceptionUtils.getStackTrace(e));
        }
    }

    @Override
    public TransformExpressionTree compileToExpressionTree(String expression) {
        CharStream charStream = new ANTLRInputStream(expression);
        PQL2Lexer lexer = new PQL2Lexer(charStream);
        lexer.setTokenFactory(new CommonTokenFactory(true));
        TokenStream tokenStream = new UnbufferedTokenStream<CommonToken>(lexer);
        PQL2Parser parser = new PQL2Parser(tokenStream);
        parser.setErrorHandler(new BailErrorStrategy());

        // Parse
        ParseTree parseTree = parser.expression();

        ParseTreeWalker walker = new ParseTreeWalker();
        Pql2AstListener listener = new Pql2AstListener(expression);
        walker.walk(listener, parseTree);

        final AstNode rootNode = listener.getRootNode();
        return TransformExpressionTree.buildTree(rootNode);
    }
}