weka.clusterers.InstanceWithCanopyAssignments.java Source code

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Here is the source code for weka.clusterers.InstanceWithCanopyAssignments.java

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/*
 *   This program 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 3 of the License, or
 *   (at your option) any later version.
 *
 *   This program 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 this program.  If not, see <http://www.gnu.org/licenses/>.
 */

/*
 *    InstanceWithCanopyAssignments
 *    Copyright (C) 2014 University of Waikato, Hamilton, New Zealand
 *
 */

package weka.clusterers;

import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.Serializable;
import java.util.zip.GZIPInputStream;
import java.util.zip.GZIPOutputStream;

import org.apache.commons.codec.binary.Base64;

import weka.core.Instance;

/**
 * Class that encapsulates an instance with its canopy assignments
 *
 * @author Mark Hall (mhall{[at]}pentaho{[dot]}com)
 * @version $Revision: $
 */
public class InstanceWithCanopyAssignments implements Serializable {

    /** For serialization */
    private static final long serialVersionUID = 4846204264955741589L;

    public static String SEPARATOR = "@@::@@";
    public static String LONG_SEPARATOR = "@";

    /** The instance */
    protected Instance m_instance;

    /** The canopies that it is assigned to */
    protected long[] m_canopies;

    public InstanceWithCanopyAssignments(Instance inst, long[] canopies) {
        m_instance = inst;
        m_canopies = canopies;
    }

    public Instance getInstance() {
        return m_instance;
    }

    public long[] getCanopyAssignments() {
        return m_canopies;
    }

    @Override
    public String toString() {
        StringBuilder b = new StringBuilder();

        b.append(m_instance.toString());
        b.append(SEPARATOR);
        for (int i = 0; i < m_canopies.length; i++) {

            b.append(m_canopies[i]);
            if (i != m_canopies.length - 1) {
                b.append(LONG_SEPARATOR);
            }
        }

        return b.toString();
    }

    public String toStringBase64() {
        StringBuilder b = new StringBuilder();

        b.append(m_instance.toString());

        try {
            b.append(SEPARATOR).append(encodeToBase64(m_canopies));
        } catch (Exception ex) {
            ex.printStackTrace();
        }

        return b.toString();
    }

    protected String encodeToBase64(long[] canopies) throws Exception {

        // object to bytes
        ByteArrayOutputStream bao = new ByteArrayOutputStream();
        BufferedOutputStream bos = new BufferedOutputStream(bao);
        ObjectOutputStream oo = null;
        try {
            oo = new ObjectOutputStream(bos);
            oo.writeObject(canopies);
            oo.flush();
        } finally {
            if (oo != null) {
                oo.close();
            }
        }

        byte[] bytes = bao.toByteArray();

        // bytes to base 64 string
        String string = null;

        ByteArrayOutputStream baos = new ByteArrayOutputStream();
        GZIPOutputStream gzos = new GZIPOutputStream(baos);
        bos = new BufferedOutputStream(gzos);
        try {
            bos.write(bytes);
            bos.flush();
        } finally {
            if (bos != null) {
                bos.close();
            }
        }

        string = new String(Base64.encodeBase64(baos.toByteArray()));

        return string;
    }

    public static String[] splitInstanceAndEncodedCanopies(String instanceAndCanopies) {
        return instanceAndCanopies.split(SEPARATOR);
    }

    public static long[] decodeCanopiesNormal(String canopies) {
        String[] parts = canopies.split(LONG_SEPARATOR);

        long[] canopiesL = new long[parts.length];

        for (int i = 0; i < parts.length; i++) {
            canopiesL[i] = Long.parseLong(parts[i].trim());
        }

        return canopiesL;
    }

    public static long[] decodeCanopiesFromBase64(String base64) throws Exception {
        byte[] bytes;
        long[] canopies = null;

        if (base64 == null) {
            bytes = new byte[] {};
        } else {
            bytes = Base64.decodeBase64(base64.getBytes());
        }

        if (bytes.length > 0) {
            ByteArrayInputStream bais = new ByteArrayInputStream(bytes);
            GZIPInputStream gzip = new GZIPInputStream(bais);
            BufferedInputStream bi = new BufferedInputStream(gzip);

            try {
                byte[] result = new byte[] {};

                byte[] extra = new byte[1000000];
                int nrExtra = bi.read(extra);
                while (nrExtra >= 0) {
                    // add it to bytes...
                    //
                    int newSize = result.length + nrExtra;
                    byte[] tmp = new byte[newSize];
                    for (int i = 0; i < result.length; i++) {
                        tmp[i] = result[i];
                    }
                    for (int i = 0; i < nrExtra; i++) {
                        tmp[result.length + i] = extra[i];
                    }

                    // change the result
                    result = tmp;
                    nrExtra = bi.read(extra);
                }
                bytes = result;
            } finally {
                gzip.close();
            }

            bais = new ByteArrayInputStream(bytes);
            ObjectInputStream ois = new ObjectInputStream(bais);
            try {
                canopies = (long[]) ois.readObject();
            } finally {
                ois.close();
            }
        }

        if (canopies == null || canopies.length == 0) {
            throw new Exception("No canopy assignments decoded!");
        }

        return canopies;
    }
}