com.ibm.research.rdf.store.cmd.QueryRdfStore.java Source code

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Here is the source code for com.ibm.research.rdf.store.cmd.QueryRdfStore.java

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/******************************************************************************
 * Copyright (c) 2015 IBM Corporation.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *****************************************************************************/
package com.ibm.research.rdf.store.cmd;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileReader;
import java.io.IOException;
import java.sql.Connection;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

import com.hp.hpl.jena.query.Dataset;
import com.hp.hpl.jena.query.Query;
import com.hp.hpl.jena.query.QueryExecution;
import com.hp.hpl.jena.query.QuerySolution;
import com.hp.hpl.jena.query.ResultSet;
import com.hp.hpl.jena.rdf.model.Model;
import com.ibm.research.rdf.store.Context;
import com.ibm.research.rdf.store.Store;
import com.ibm.research.rdf.store.Store.Backend;
import com.ibm.research.rdf.store.StoreManager;
import com.ibm.research.rdf.store.jena.RdfStoreException;
import com.ibm.research.rdf.store.jena.RdfStoreFactory;
import com.ibm.research.rdf.store.jena.RdfStoreQueryExecutionFactory;
import com.ibm.research.rdf.store.jena.RdfStoreQueryFactory;

public class QueryRdfStore extends ShowPredicateColumns {

    private static final Log log = LogFactory.getLog(QueryRdfStore.class);

    public static void main(String[] args) {

        AbstractRdfCommand cmd = new QueryRdfStore();
        cmd.runCmd(args, "queryrdfstore", null);

    }

    @Override
    public boolean validateParameters() {
        validParams.add("-uniondefaultgraph");
        return super.validateParameters();
    }

    @Override
    public void doWork(Connection conn) {

        if (finalArg == null) {
            System.out.println("Query not specified");
            printUsage();
            return;
        }

        String query = null;
        // check if this is a file or query String
        File file = new File(finalArg);
        if (file.exists()) {
            StringBuffer queryBuffer = new StringBuffer();
            try {
                BufferedReader br = new BufferedReader(new FileReader(file));
                String line = null;

                while ((line = br.readLine()) != null) {
                    queryBuffer.append(line);
                }
                br.close();
            } catch (IOException e) {
                System.out.println(e.getLocalizedMessage());
                printUsage();
                return;
            }
            query = queryBuffer.toString();
        } else {
            query = finalArg;
        }

        try {
            Store store = StoreManager.connectStore(conn, Backend.valueOf(params.get("-backend")),
                    params.get("-schema"), storeName, Context.defaultContext);
            String unionDef = params.get("-uniondefaultgraph");
            if (unionDef != null && unionDef.equalsIgnoreCase("true")) {
                store.getContext().set(Context.unionDefaultGraph, true);
            }

            Dataset ds = RdfStoreFactory.connectDataset(store, conn, Backend.valueOf(params.get("-backend")));
            Query q = RdfStoreQueryFactory.create(query);
            QueryExecution qe = RdfStoreQueryExecutionFactory.create(q, ds);

            long rows = 0;
            Model m = null;
            long start = System.currentTimeMillis();

            if (q.isSelectType()) {
                ResultSet rs = qe.execSelect();
                while (rs.hasNext()) {
                    QuerySolution qs = rs.next();
                    System.out.println(qs);
                    System.out.println();
                    rows++;
                }
            } else if (q.isDescribeType()) {
                m = qe.execDescribe();
                m.write(System.out, "N-TRIPLE");
            } else if (q.isAskType()) {
                System.out.println(qe.execAsk());

            } else if (q.isConstructType()) {
                m = qe.execConstruct();
                m.write(System.out, "N-TRIPLE");
            }

            long end = System.currentTimeMillis();
            qe.close();
            if (m != null) {
                System.out.println("Number of Rows  : " + m.size());
                m.close();
            } else {
                System.out.println("Number of Rows  : " + rows);
            }
            System.out.println("Time taken      : " + (end - start) + " ms");
        } catch (RdfStoreException e) {
            log.error(e);
            System.out.println(e.getLocalizedMessage());
        } catch (Exception e) {
            log.error(e);
            System.out.println(e.getLocalizedMessage());
        }

    }

    @Override
    public void printUsage() {
    }

}