001/*
002 * Copyright (c) 2003-2010 The Regents of the University of California.
003 * All rights reserved.
004 *
005 * '$Author: welker $'
006 * '$Date: 2010-05-06 05:21:26 +0000 (Thu, 06 May 2010) $' 
007 * '$Revision: 24234 $'
008 * 
009 * Permission is hereby granted, without written agreement and without
010 * license or royalty fees, to use, copy, modify, and distribute this
011 * software and its documentation for any purpose, provided that the above
012 * copyright notice and the following two paragraphs appear in all copies
013 * of this software.
014 *
015 * IN NO EVENT SHALL THE UNIVERSITY OF CALIFORNIA BE LIABLE TO ANY PARTY
016 * FOR DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
017 * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF
018 * THE UNIVERSITY OF CALIFORNIA HAS BEEN ADVISED OF THE POSSIBILITY OF
019 * SUCH DAMAGE.
020 *
021 * THE UNIVERSITY OF CALIFORNIA SPECIFICALLY DISCLAIMS ANY WARRANTIES,
022 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
023 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE
024 * PROVIDED HEREUNDER IS ON AN "AS IS" BASIS, AND THE UNIVERSITY OF
025 * CALIFORNIA HAS NO OBLIGATION TO PROVIDE MAINTENANCE, SUPPORT, UPDATES,
026 * ENHANCEMENTS, OR MODIFICATIONS.
027 *
028 */
029
030package org.ecoinformatics.seek.util;
031
032import java.util.Hashtable;
033
034import ptolemy.actor.TypedAtomicActor;
035import ptolemy.actor.TypedIOPort;
036import ptolemy.data.StringToken;
037import ptolemy.data.Token;
038import ptolemy.data.type.BaseType;
039import ptolemy.kernel.CompositeEntity;
040import ptolemy.kernel.util.IllegalActionException;
041import ptolemy.kernel.util.NameDuplicationException;
042
043public class FieldChooser extends TypedAtomicActor {
044        public TypedIOPort input = new TypedIOPort(this, "input", true, false); // the
045                                                                                                                                                        // record
046                                                                                                                                                        // input
047        public TypedIOPort inputChoice = new TypedIOPort(this, "inputChoice", true,
048                        false); // the field in the record to choose
049        public TypedIOPort output = new TypedIOPort(this, "output", false, true); // output
050                                                                                                                                                                // the
051                                                                                                                                                                // users
052                                                                                                                                                                // choice
053
054        /**
055         * Construct an actor with the given container and name.
056         * 
057         * @param container
058         *            The container.
059         * @param name
060         *            The name of this actor.
061         * @exception IllegalActionException
062         *                If the actor cannot be contained by the proposed
063         *                container.
064         * @exception NameDuplicationException
065         *                If the container already has an actor with this name.
066         */
067        public FieldChooser(CompositeEntity container, String name)
068                        throws NameDuplicationException, IllegalActionException {
069                super(container, name);
070                input.setTypeEquals(BaseType.GENERAL);
071                inputChoice.setTypeEquals(BaseType.STRING);
072                output.setTypeEquals(BaseType.GENERAL);
073        }
074
075        /**
076         * Send a random number with a uniform distribution to the output. This
077         * number is only changed in the prefire() method, so it will remain
078         * constant throughout an iteration.
079         * 
080         * @exception IllegalActionException
081         *                If there is no director.
082         */
083        public void fire() throws IllegalActionException {
084                super.fire();
085                int inputChoiceWidth = inputChoice.getWidth();
086                if (inputChoiceWidth > 1) {
087                        throw new IllegalActionException(
088                                        "The inputChoice port can only accept "
089                                                        + "one channel of data.");
090                }
091
092                Token inputChoiceToken = inputChoice.get(0);
093                String inputChoiceVal = inputChoiceToken.toString();
094                // take the quotes off the string
095                inputChoiceVal = inputChoiceVal.substring(1,
096                                inputChoiceVal.length() - 1);
097
098                int width = input.getWidth();
099                for (int i = 0; i < width; i++) { // get the records and output the
100                                                                                        // correct field
101                        if (input.hasToken(i)) {
102                                Token token = input.get(i);
103                                String value = token.toString();
104                                Hashtable fields = new Hashtable();
105                                value = value.substring(1, value.length() - 1); // chop the
106                                                                                                                                // braces
107                                while (value.length() != 0) {
108                                        String val;
109                                        if (value.indexOf(",") == -1) { // at the end of the string
110                                                val = value.substring(0, value.length());
111                                                value = "";
112                                        } else {
113                                                val = value.substring(0, value.indexOf(","));
114                                        }
115                                        String hashname = val.substring(0, val.indexOf("="));
116                                        String hashval = val.substring(val.indexOf("=") + 1, val
117                                                        .length());
118                                        fields.put(hashname.trim(), hashval.trim());
119                                        if (val.length() + 1 < value.length()) {
120                                                value = value.substring(val.length() + 1, value
121                                                                .length());
122                                        }
123                                }
124
125                                if (!fields.containsKey(inputChoiceVal)) {
126                                        throw new IllegalActionException("No such key '"
127                                                        + inputChoiceVal + "'...fields is "
128                                                        + fields.toString());
129                                }
130
131                                try {
132                                        sendToken(fields.get(inputChoiceVal));
133                                } catch (ClassCastException cce) {
134                                        throw new IllegalActionException(
135                                                        "Error casting the output token '"
136                                                                        + fields.get(inputChoiceVal).toString()
137                                                                        + "' to the appropriate output port type: "
138                                                                        + cce.getMessage());
139                                }
140                        }
141                }
142        }
143
144        /**
145         * sends the token. this can be overwritten to send different types of
146         * tokens besides strings.
147         */
148        protected void sendToken(Object o) throws ClassCastException,
149                        IllegalActionException {
150                output.send(0, new StringToken((String) o));
151                // getToken will always return a stringToken here.
152        }
153
154        /**
155   *
156   */
157        public boolean prefire() throws IllegalActionException {
158                return super.prefire();
159        }
160}