com.antsdb.saltedfish.sql.mysql.MysqlParserFactory.java Source code

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Here is the source code for com.antsdb.saltedfish.sql.mysql.MysqlParserFactory.java

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/*-------------------------------------------------------------------------------------------------
 _______ __   _ _______ _______ ______  ______
 |_____| | \  |    |    |______ |     \ |_____]
 |     | |  \_|    |    ______| |_____/ |_____]
    
 Copyright (c) 2016, antsdb.com and/or its affiliates. All rights reserved. *-xguo0<@
    
 This program is free software: you can redistribute it and/or modify it under the terms of the
 GNU Affero General Public License, version 3, as published by the Free Software Foundation.
    
 You should have received a copy of the GNU Affero General Public License along with this program.
 If not, see <https://www.gnu.org/licenses/agpl-3.0.txt>
-------------------------------------------------------------------------------------------------*/
package com.antsdb.saltedfish.sql.mysql;

import org.antlr.v4.runtime.ANTLRInputStream;
import org.antlr.v4.runtime.BailErrorStrategy;
import org.antlr.v4.runtime.CharStream;
import org.antlr.v4.runtime.CommonTokenStream;
import org.antlr.v4.runtime.tree.ParseTree;
import org.slf4j.Logger;

import com.antsdb.saltedfish.lexer.MysqlLexer;
import com.antsdb.saltedfish.lexer.MysqlParser;
import com.antsdb.saltedfish.lexer.MysqlParser.ScriptContext;
import com.antsdb.saltedfish.lexer.MysqlParser.Sql_stmtContext;
import com.antsdb.saltedfish.sql.DdlGenerator;
import com.antsdb.saltedfish.sql.Generator;
import com.antsdb.saltedfish.sql.GeneratorContext;
import com.antsdb.saltedfish.sql.Session;
import com.antsdb.saltedfish.sql.SqlParserFactory;
import com.antsdb.saltedfish.sql.mysql.InstructionGenerator;
import com.antsdb.saltedfish.sql.vdm.Instruction;
import com.antsdb.saltedfish.sql.vdm.Parameters;
import com.antsdb.saltedfish.sql.vdm.Script;
import com.antsdb.saltedfish.sql.vdm.VdmContext;
import com.antsdb.saltedfish.util.UberUtil;

public class MysqlParserFactory extends SqlParserFactory {
    static Logger _log = UberUtil.getThisLogger();

    @Override
    public Script parse(Session session, CharStream cs) {
        ScriptContext scriptCtx = parse(cs);
        GeneratorContext ctx = new GeneratorContext(session);
        InstructionGenerator.scan(ctx, scriptCtx);
        Instruction code = (Instruction) InstructionGenerator.generate(ctx, scriptCtx);
        Script script = new Script(code, ctx.getParameterCount(), ctx.getVariableCount(), cs.toString());
        return script;
    }

    @Override
    public Object run(VdmContext ctx, Parameters params, CharStream cs) {
        ScriptContext rule = parse(cs);
        GeneratorContext gctx = new GeneratorContext(ctx.getSession());
        gctx.setCompileDdl(true);
        InstructionGenerator.scan(gctx, rule);
        Object result = run(gctx, ctx, params, rule);
        return result;
    }

    private Object run(GeneratorContext gctx, VdmContext ctx, Parameters params, ScriptContext rule) {
        Object result = null;
        for (Sql_stmtContext i : rule.sql_stmt()) {
            result = run(gctx, ctx, params, i);
        }
        return result;
    }

    private Object run(GeneratorContext gctx, VdmContext ctx, Parameters params, Sql_stmtContext rule) {
        ParseTree stmt = rule.getChild(0);
        Generator<ParseTree> generator = InstructionGenerator.getGenerator(stmt);
        Instruction code = generator.gen(gctx, stmt);
        if (code == null) {
            return null;
        }
        try {
            Object result = code.run(ctx, params, 0);
            return result;
        } finally {
            if (generator instanceof DdlGenerator<?>) {
                // mysql commits after every ddl statement
                ctx.getSession().commit();
            }
        }
    }

    static MysqlParser.ScriptContext parse(String sql) {
        return parse(new ANTLRInputStream(sql));
    }

    static MysqlParser.ScriptContext parse(CharStream cs) {
        if (isCommtedStatement(cs)) {
            String s = cs.toString();
            s = s.substring(9);
            s = s.substring(0, s.length() - 3);
            cs = new ANTLRInputStream(s);
        }
        MysqlLexer lexer = new MysqlLexer(cs);
        CommonTokenStream tokens = new CommonTokenStream(lexer);
        tokens.setTokenSource(lexer);
        MysqlParser parser = new MysqlParser(tokens);
        parser.setErrorHandler(new BailErrorStrategy());
        boolean success = false;
        try {
            MysqlParser.ScriptContext script = parser.script();
            success = true;
            return script;
        } finally {
            if (!success && (parser.lastStatement != null)) {
                _log.debug("last passed statement: {}", ((ParseTree) parser.lastStatement).getText());
            }
        }
    }

    /**
     * mysql executes statement in a specially formatted comment like
     * / *!40101 SET NAMES utf8 * /;
     * @param cs
     * @return
     */
    private static boolean isCommtedStatement(CharStream cs) {
        int idx = cs.index();
        if (cs.LA(idx + 1) != '/') {
            return false;
        }
        if (cs.LA(idx + 2) != '*') {
            return false;
        }
        if (cs.LA(idx + 3) != '!') {
            return false;
        }
        if (cs.LA(idx + 4) != '4') {
            return false;
        }
        return true;
    }
}