com.hp.hpl.jena.sparql.algebra.MyOpVisitor.java Source code

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Here is the source code for com.hp.hpl.jena.sparql.algebra.MyOpVisitor.java

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/*******************************************************************************
 * Copyright (c) 2012 Nikos Papailiou. 
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the GNU Public License v3.0
 * which accompanies this distribution, and is available at
 * http://www.gnu.org/licenses/gpl.html
 * 
 * Contributors:
 *     Nikos Papailiou - initial API and implementation
 ******************************************************************************/
package com.hp.hpl.jena.sparql.algebra;

import java.util.Iterator;
import java.util.List;
import java.util.Set;

import java.io.IOException;

import org.apache.hadoop.fs.FileSystem;
import org.apache.hadoop.fs.Path;

import org.apache.hadoop.conf.Configuration;

import gr.ntua.h2rdf.partialJoin.JoinPlaner;
import gr.ntua.h2rdf.partialJoin.OutputBuffer;
import gr.ntua.h2rdf.partialJoin.QueryProcessor;

import com.hp.hpl.jena.graph.Triple;
import com.hp.hpl.jena.query.Query;
import com.hp.hpl.jena.sparql.algebra.op.*;
import com.hp.hpl.jena.sparql.core.Var;
import com.hp.hpl.jena.sparql.expr.Expr;
import com.hp.hpl.jena.sparql.syntax.PatternVars;

public class MyOpVisitor extends OpVisitorBase {

    private Query query;
    private String id;
    private OpBGP opBGP;
    private boolean ask;

    public MyOpVisitor(String id, Query query) {
        this.query = query;
        this.id = id;
        ask = true;
    }

    public void visit(OpBGP opBGP) {
        System.out.println("bgp");
        System.out.println(opBGP.toString());
        this.opBGP = opBGP;
    }

    public void visit(OpJoin opJoin) {
        System.out.println("join");
        System.out.println(opJoin.toString());
    }

    public void visit(OpLeftJoin opLeftJoin) {
        System.out.println("left join");
        System.out.println(opLeftJoin.toString());
    }

    public void visit(OpUnion opUnion) {
        System.out.println("union");
        System.out.println(opUnion.toString());
    }

    public void visit(OpFilter opFilter) {
        System.out.println("filter");
        System.out.println(opFilter.toString());
        /*//JoinPlanner.setFilterVars();
        Iterator<Expr> it = opFilter.getExprs().iterator();
        while(it.hasNext()){
           Expr e =it.next();
           Iterator<Expr> a = e.getFunction().getArgs().iterator();
          System.out.println(e.getFunction().getOpName());
           while(a.hasNext()){
         Expr temp = a.next();
         if(temp.isVariable())
            JoinPlaner.filter(temp.toString(),e.getFunction());
           }
        }*/
    }

    public void visit(OpGraph opGraph) {
        System.out.println("graph");
        System.out.println(opGraph.toString());
    }

    public void visit(OpQuadPattern quadPattern) {
        System.out.println("quad");
        System.out.println(quadPattern.toString());
    }

    public void visit(OpDatasetNames dsNames) {
        System.out.println("dsNames");
        System.out.println(dsNames.toString());
    }

    public void visit(OpTable table) {
        System.out.println("table");
        System.out.println(table.toString());
    }

    public void visit(OpExt opExt) {
        System.out.println("ext");
        System.out.println(opExt.toString());
    }

    public void visit(OpOrder opOrder) {
        System.out.println("order");
        System.out.println(opOrder.toString());
    }

    public void visit(OpProject opProject) {
        System.out.println("project");
        System.out.println(opProject.toString());
        ask = false;
    }

    public void visit(OpDistinct opDistinct) {
        System.out.println("distinct");
        System.out.println(opDistinct.toString());
    }

    public void visit(OpSlice opSlice) {
        System.out.println("slice");
        System.out.println(opSlice.toString());
    }

    public void execute() {

        Configuration conf = new Configuration();
        FileSystem fs = null;
        try {
            fs = FileSystem.get(conf);
            Path out = new Path("output");
            if (!fs.exists(out)) {
                fs.delete(out, true);
                fs.mkdirs(out);
            }
        } catch (IOException e) {
            e.printStackTrace();
        }

        Triple[] Q = new Triple[0];
        Q = opBGP.getPattern().getList().toArray(Q);
        Set<Var> vars = PatternVars.vars(query.getQueryPattern());

        JoinPlaner.setid(id);
        JoinPlaner.newVaRS(vars);
        try {
            JoinPlaner.form(Q);
            JoinPlaner.removeNonJoiningVaribles(Q);
            int i = 0;
            while (!JoinPlaner.isEmpty()) {
                String v = JoinPlaner.getNextJoin();
                System.out.println(v);
                i++;
            }
            if (i == 0) {
                Path outFile = new Path("output/Join_" + id + "_" + 0);
                OutputBuffer out = new OutputBuffer(outFile, fs);
                //if (fs.exists(outFile)) {
                //   fs.delete(outFile,true);
                //}
                //fs.create(outFile);
                QueryProcessor.executeSelect(Q[0], out, "P0");
            }
        } catch (Exception e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

    }

}