edu.stanford.junction.props2.sample.CollectionProp.java Source code

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Here is the source code for edu.stanford.junction.props2.sample.CollectionProp.java

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/*
 * Copyright (C) 2010 Stanford University
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package edu.stanford.junction.props2.sample;

import org.json.JSONObject;
import org.json.JSONArray;
import org.json.JSONException;
import java.util.*;
import edu.stanford.junction.props2.Prop;
import edu.stanford.junction.props2.IWithStateAction;
import edu.stanford.junction.props2.IPropState;

abstract public class CollectionProp extends Prop {

    public CollectionProp(String propName, String propReplicaName, IPropState state, long seqNum) {
        super(propName, propReplicaName, state, seqNum);
    }

    public CollectionProp(String propName, String propReplicaName, IPropState state) {
        super(propName, propReplicaName, state, 0);
    }

    protected IPropState newStateWith(final Collection<JSONObject> items) {
        return withState(new IWithStateAction<IPropState>() {
            public IPropState run(IPropState state) {
                return ((CollectionState) state).newWith(items);
            }
        });
    }

    protected IPropState newState() {
        return newStateWith(new ArrayList<JSONObject>());
    }

    public void add(JSONObject item) {
        addOperation(newAddOp(item));
    }

    public void replace(JSONObject item1, JSONObject item2) {
        addOperation(newReplaceOp(item1, item2));
    }

    public void delete(JSONObject item) {
        addOperation(newDeleteOp(item));
    }

    public void clear() {
        addOperation(newClearOp());
    }

    public Collection<JSONObject> items() {
        return withState(new IWithStateAction<Collection<JSONObject>>() {
            public Collection<JSONObject> run(IPropState state) {
                return ((CollectionState) state).items();
            }
        });
    }

    // Debug
    public void doRandom() {
        ArrayList<String> words = new ArrayList<String>();
        words.add("dude");
        words.add("apple");
        words.add("hat");
        words.add("cat");
        words.add("barge");
        words.add("horse");
        words.add("mango");
        words.add("code");
        Random rng = new Random();
        if (rng.nextInt(2) == 0) {
            JSONObject item = new JSONObject();
            String word = words.get(rng.nextInt(words.size()));
            try {
                item.put("id", word.hashCode());
                item.put("str", word);
                add(item);
            } catch (JSONException e) {
            }
        } else {
            Iterator<JSONObject> it = items().iterator();
            if (it.hasNext()) {
                delete(it.next());
            }
        }
    }

    protected IPropState reifyState(JSONObject obj) {
        JSONArray a = obj.optJSONArray("items");
        ArrayList<JSONObject> items = new ArrayList<JSONObject>();
        for (int i = 0; i < a.length(); i++) {
            items.add(a.optJSONObject(i));
        }
        return newStateWith(items);
    }

    protected JSONObject newAddOp(JSONObject item) {
        JSONObject obj = new JSONObject();
        try {
            obj.put("type", "addOp");
            obj.put("item", item);
        } catch (JSONException e) {
        }
        return obj;
    }

    protected JSONObject newDeleteOp(JSONObject item) {
        JSONObject obj = new JSONObject();
        try {
            obj.put("type", "deleteOp");
            obj.put("item", item);
        } catch (JSONException e) {
        }
        return obj;
    }

    protected JSONObject newReplaceOp(JSONObject item1, JSONObject item2) {
        JSONObject obj = new JSONObject();
        try {
            obj.put("type", "replaceOp");
            obj.put("item1", item1);
            obj.put("item2", item2);
        } catch (JSONException e) {
        }
        return obj;
    }

    protected JSONObject newClearOp() {
        JSONObject obj = new JSONObject();
        try {
            obj.put("type", "clearOp");
        } catch (JSONException e) {
        }
        return obj;
    }

}