ilpool.java

与postgresql数据库结合的数据库水印软件包

/*
 * 
 * Copyright 2003,2004 The Watermill Team
 *
 * This file is part of Watermill.
 *
 *    Watermill is free software; you can redistribute it and/or modify
 *    it under the terms of the GNU General Public License as published by
 *    the Free Software Foundation; either version 2 of the License, or
 *    (at your option) any later version.
 *
 *    Watermill is distributed in the hope that it will be useful,
 *    but WITHOUT ANY WARRANTY; without even the implied warranty of
 *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *    GNU General Public License for more details.
 *
 *    You should have received a copy of the GNU General Public License
 *    along with Watermill; if not, write to the Free Software
 *    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 */
package Watermill.kernel;

import java.io.*;
import java.util.*;
import com.cflex.util.lpSolve.*;

public class ILPool extends Pool implements Serializable{

public static Identifiers identifiers;
public static DependencyMatrix depMatrix;
public static LpModel lpIn;
public static int lc,seed,gd;
public static Document doc;
public static String request;

public ILPool(String ipn,Document id,WSchema iws)throws Exception{
	super(ipn,id,iws);
	doc = id;
	
	
	identifiers=id.getModifiableValuesIdentifiers(wschema.getLocalConstraints());
	Msg.debug("Identifiers:"+identifiers.toString());

	depMatrix=id.getDependency(wschema.getGlobalConstraints());
	Msg.debug("DepMatrix:"+depMatrix.toString());
	
	reductMatrix();
	lpIn = lpModele();
	lpIn.printLp();
	
}

public static void reductMatrix ()throws Exception{
    // choose a random subset of identifiers such that their values is larger than local distortion
    Random r=new Random(seed);
    DependencyMatrix dep=(DependencyMatrix)depMatrix.clone();
    
    for (int j=0;j<dep.size();j++){
	Identifiers id = (Identifiers)dep.get(j);
	for (int i=0; i<id.size(); i++){
	    boolean b=r.nextBoolean();
	    // XIdentifier ident = (XIdentifier)id.get(i) ;
	    Identifier ident = (Identifier)id.get(i);
	    ident.maxDistortion=lc;
	    Value value = doc.getValue(ident);
	    int x = value.get();
	    if (!b | x <=lc) {
		id.remove(ident);
	    }
	}
    }
    depMatrix=dep;
}

public static LpModel lpModele ()throws Exception{
	double globale = 0.0;
	int Ldistinf = 0;
	int indice = 0;
	int Ldistsup =0;int num = 0;
	try{
	    //reductMatrix();
	for (int j=0;j<depMatrix.size();j++){
	Identifiers id = (Identifiers)depMatrix.get(j);
	lpIn = new LpModel(0, id.size());
	lpIn.debug = LpModel.FALSE;
	lpIn.verbose = LpModel.FALSE;
	lpIn.trace = LpModel.FALSE;
	double v1[] = new double[id.size()+1]; // objective function
	double v2[] = new double[id.size()+1]; // model of the global constraint
	 for (int i=0; i<id.size(); i++){
	     double v[] = new double[id.size()+1]; // model of the local constraint
	     Ldistsup = 2*lc ;
	     double rhs;
	     indice = i+1;
	     v2[i+1] = 1 ;
	     v1[i+1] = -1;
	     lpIn.setObjFn(v1);
	     lpIn.setMaximum();
	     num++;
	     v[i+1]=0;
	     v[indice] = 1;
	     rhs = Ldistinf;
	     lpIn.addConstraint(v, LpModel.GE, rhs);
	     rhs = Ldistsup;
	     lpIn.addConstraint(v, LpModel.LE, rhs);
	     lpIn.setInt(indice, LpModel.TRUE);
	 }
	globale = num*lc;
	lpIn.addConstraint(v2, LpModel.GE, globale);
	lpIn.addConstraint(v2, LpModel.LE, globale);
	
	}}
	catch (Exception ex){ ex.printStackTrace(); }
	return lpIn;
   }
    

    public Watermark watermark(Document doc,int is) {
	Watermark res=new Watermark();
	seed = is;
	try {
	    lpIn = lpModele(); // this command generates an exception
	    Msg.debug("Watermark");
	    for (int i=0;i<depMatrix.size();i++){
		Identifiers ids=(Identifiers)depMatrix.get(i);
		Msg.debug("identifiers : "+ids.toString());
		LpSolver lpsolve = new LpSolver(lpIn);
		int q = lpsolve.solve();
		int[]result = new int[ids.size()];
		for(int j=0; j<ids.size();j++){
		    result[j] = (int)lpIn.getResult(j+1)-lc ;
		}
		for(int j=0;j<ids.size();j++){
		    Identifier id=(Identifier)ids.get(j);
		    Msg.debug("watermarking in identifier "+id.toString());
		    int value = result[j];
		    if(value!= 0){
			Value v1 = new Value(value);
			doc.addValue(id,v1);
			res.put(id,new Value(value));}
		}
	    }
	}
	catch (Exception e) {
	    Msg.debug("An exception has occured with resolving linear constraints");
	}
	return res;
    }
}