CSVProcessor.java

//	---------------------------------------------------------------------------
//	jWebSocket - CSV Token Processor
//	Copyright (c) 2010 Alexander Schulze, Innotrade GmbH
//	---------------------------------------------------------------------------
//	This program is free software; you can redistribute it and/or modify it
//	under the terms of the GNU Lesser 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 Lesser General Public License for
//	more details.
//	You should have received a copy of the GNU Lesser General Public License along
//	with this program; if not, see <http://www.gnu.org/licenses/lgpl.html>.
//	---------------------------------------------------------------------------
package org.jwebsocket.packetProcessors;

import java.io.UnsupportedEncodingException;
import java.util.Collection;
import java.util.Iterator;

import org.jwebsocket.api.WebSocketPacket;
import org.jwebsocket.kit.RawPacket;
import org.jwebsocket.token.Token;
import org.jwebsocket.token.TokenFactory;

/**
 * converts CSV formatted data packets into tokens and vice versa.
 * @author aschulze
 */
public class CSVProcessor {

    // TODO: Logging cannot be used in common module because not supported on all clients
    // private static Logger log = Logging.getLogger(CSVProcessor.class);
    /**
     * converts a CSV formatted data packet into a token.
     * @param aDataPacket
     * @return
     */
    public static Token packetToToken(WebSocketPacket aDataPacket) {
        Token lToken = TokenFactory.createToken();
        try {
            String aData = aDataPacket.getString("UTF-8");
            String[] lItems = aData.split(",");
            for (int i = 0; i < lItems.length; i++) {
                String[] lKeyVal = lItems[i].split("=", 2);
                if (lKeyVal.length == 2) {
                    String lVal = lKeyVal[1];
                    if (lVal.length() <= 0) {
                        lToken.setValidated(lKeyVal[0], null);
                    } else if (lVal.startsWith("\"") && lVal.endsWith("\"")) {
                        // unescape commata by \x2C
                        lVal = lVal.replace("\\x2C", ",");
                        // unescape quotes by \x22
                        lVal = lVal.replace("\\x22", "\"");
                        lToken.setValidated(lKeyVal[0], lVal.substring(1, lVal.length() - 1));
                    } else {
                        lToken.setValidated(lKeyVal[0], lVal);
                    }
                }
            }
        } catch (UnsupportedEncodingException ex) {
            // TODO: process exception
            // log.error(ex.getClass().getSimpleName() + ": " + ex.getMessage());
        }
        return lToken;
    }

    private static String stringToCSV(String aString) {
        // escape commata by \x2C
        aString = aString.replace(",", "\\x2C");
        // escape quotes by \x22
        aString = aString.replace("\"", "\\x22");
        return ("\"" + aString + "\"");
    }

    private static String collectionToCSV(Collection<Object> aCollection) {
        String lRes = "";
        for (Object lItem : aCollection) {
            String llRes = objectToCSV(lItem);
            lRes += llRes + "|";
        }
        if (lRes.length() > 1) {
            lRes = lRes.substring(0, lRes.length() - 1);
        }
        lRes = "[" + lRes + "]";
        return lRes;
    }

    private static String objectToCSV(Object aObj) {
        String lRes;
        if (aObj == null) {
            lRes = "null";
        } else if (aObj instanceof String) {
            lRes = stringToCSV((String) aObj);
        } else if (aObj instanceof Collection) {
            lRes = collectionToCSV((Collection<Object>) aObj);
        } else {
            lRes = "\"" + aObj.toString() + "\"";
        }
        return lRes;
    }

    /**
     * converts a token into a CSV formatted data packet.
     * @param aToken
     * @return
     */
    public static WebSocketPacket tokenToPacket(Token aToken) {
        String lData = "";
        Iterator<String> lIterator = aToken.getKeyIterator();
        while (lIterator.hasNext()) {
            String lKey = lIterator.next();
            Object lVal = aToken.getString(lKey);
            lData +=
                    lKey + "=" + objectToCSV(lVal)
                    + (lIterator.hasNext() ? "," : "");
        }
        WebSocketPacket lPacket = null;
        try {
            lPacket = new RawPacket(lData, "UTF-8");
        } catch (UnsupportedEncodingException ex) {
            // TODO: process exception
            // log.error(ex.getClass().getSimpleName() + ": " + ex.getMessage());
        }
        return lPacket;
    }
}