com.linkedin.bowser.core.grammar.AbstractNQLQueryBuilder.java Source code

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Here is the source code for com.linkedin.bowser.core.grammar.AbstractNQLQueryBuilder.java

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/*
 * Copyright 2010-2011 LinkedIn Corporation
 * 
 * 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.bowser.core.grammar;

import java.util.HashMap;
import java.util.HashSet;
import java.util.Map;
import java.util.Set;

import jsr166y.ForkJoinPool;

import org.antlr.runtime.RecognizerSharedState;
import org.antlr.runtime.tree.TreeNodeStream;
import org.antlr.runtime.tree.TreeParser;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

import com.google.common.base.Predicate;
import com.google.common.collect.ImmutableMap;
import com.google.common.collect.Maps;
import com.linkedin.bowser.core.eval.EvalVisitor;
import com.linkedin.bowser.core.eval.EvalVisitorErrorProxy;
import com.linkedin.bowser.core.expn.Expn;
import com.linkedin.bowser.core.expn.ExpnVisitor;
import com.linkedin.bowser.core.objects.NQLObject;

public abstract class AbstractNQLQueryBuilder extends TreeParser {
    private final static String MODULE = AbstractNQLQueryBuilder.class.getName();
    private final static Log log = LogFactory.getLog(MODULE);

    private ForkJoinPool _pool;
    private Map<String, NQLObject> _symbolMap = new HashMap<String, NQLObject>();
    private Set<String> _localSymbols = new HashSet<String>();

    public AbstractNQLQueryBuilder(TreeNodeStream input) {
        super(input);
        _symbolMap = Maps.newHashMap();
    }

    public AbstractNQLQueryBuilder(TreeNodeStream input, RecognizerSharedState state) {
        super(input, state);
        _symbolMap = Maps.newHashMap();
    }

    public ForkJoinPool getPool() {
        return _pool;
    }

    public void setPool(ForkJoinPool pool) {
        _pool = pool;
    }

    public Map<String, NQLObject> getSymbolMap() {
        return _symbolMap;
    }

    public void setSymbolMap(Map<String, NQLObject> symbolMap) {
        _symbolMap = symbolMap;
    }

    /**
     * @param e
     * @return
     */
    public NQLObject eval(Expn e) {
        EvalVisitor eval = new EvalVisitor(_pool, ImmutableMap.copyOf(getSymbolMap()));
        ExpnVisitor<NQLObject> proxied = EvalVisitorErrorProxy.createProxiedEvalVisitor(eval);

        NQLObject result = e.accept(proxied);

        if (log.isDebugEnabled())
            log.debug("eval:" + eval.getEvalStack());

        return result;
    }

    protected void assign(String identifier, NQLObject e) {
        _symbolMap.put(identifier, e);
        _localSymbols.add(identifier);
    }

    public Map<String, NQLObject> getLocalSymbolMap() {
        return Maps.newHashMap(Maps.filterKeys(_symbolMap, new Predicate<String>() {
            @Override
            public boolean apply(String key) {
                return _localSymbols.contains(key);
            }
        }));
    }
}