org.cmg.jresp.json.GroupPredicateDeserializer.java Source code

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Here is the source code for org.cmg.jresp.json.GroupPredicateDeserializer.java

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/**
 * Copyright (c) 2013 Concurrency and Mobility Group.
 * Universita' di Firenze
 *   
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 * 
 * Contributors:
 *      Michele Loreti
 */
package org.cmg.jresp.json;

import java.lang.reflect.Type;

import org.cmg.jresp.topology.And;
import org.cmg.jresp.topology.AnyComponent;
import org.cmg.jresp.topology.GroupPredicate;
import org.cmg.jresp.topology.HasValue;
import org.cmg.jresp.topology.IsGreaterOrEqualThan;
import org.cmg.jresp.topology.IsGreaterThan;
import org.cmg.jresp.topology.IsLessOrEqualThan;
import org.cmg.jresp.topology.IsLessThan;
import org.cmg.jresp.topology.Not;
import org.cmg.jresp.topology.Or;
import org.cmg.jresp.topology.GroupPredicate.PredicateType;

import com.google.gson.JsonDeserializationContext;
import com.google.gson.JsonDeserializer;
import com.google.gson.JsonElement;
import com.google.gson.JsonObject;
import com.google.gson.JsonParseException;

/**
 * @author Michele Loreti
 *
 */
public class GroupPredicateDeserializer implements JsonDeserializer<GroupPredicate> {

    @Override
    public GroupPredicate deserialize(JsonElement json, Type typeOfT, JsonDeserializationContext context)
            throws JsonParseException {
        if (json.isJsonObject()) {
            JsonObject o = json.getAsJsonObject();
            return doDeserialize((GroupPredicate.PredicateType) context.deserialize(o.get("type"),
                    GroupPredicate.PredicateType.class), o, context);
        }
        throw new IllegalStateException("This is not a Message!");
    }

    private GroupPredicate doDeserialize(PredicateType deserialize, JsonObject json,
            JsonDeserializationContext context) {
        switch (deserialize) {
        case TRUE:
            return new AnyComponent();
        case ISEQUAL:
            return doDeserializeHasValuePredicate(json, context);
        case ISGTR:
            return doDeserializeIsGreaterThanPredicate(json, context);
        case ISGEQ:
            return doDeserializeIsGreaterOrEqualThanPredicate(json, context);
        case ISLEQ:
            return doDeserializeIsLessOrEqualThanPredicate(json, context);
        case ISLES:
            return doDeserializeIsLessThanPredicate(json, context);
        case AND:
            return doDeserializeAndPredicate(json, context);
        case OR:
            return doDeserializeOrPredicate(json, context);
        case NOT:
            return doDeserializeNotPredicate(json, context);
        }
        return null;
    }

    private GroupPredicate doDeserializeNotPredicate(JsonObject json, JsonDeserializationContext context) {
        return new Not((GroupPredicate) context.deserialize(json.get("arg"), GroupPredicate.class));
    }

    private GroupPredicate doDeserializeAndPredicate(JsonObject json, JsonDeserializationContext context) {
        return new And((GroupPredicate) context.deserialize(json.get("left"), GroupPredicate.class),
                (GroupPredicate) context.deserialize(json.get("right"), GroupPredicate.class));
    }

    private GroupPredicate doDeserializeOrPredicate(JsonObject json, JsonDeserializationContext context) {
        return new Or((GroupPredicate) context.deserialize(json.get("left"), GroupPredicate.class),
                (GroupPredicate) context.deserialize(json.get("right"), GroupPredicate.class));
    }

    private IsGreaterOrEqualThan doDeserializeIsGreaterOrEqualThanPredicate(JsonObject json,
            JsonDeserializationContext context) {
        Object o = SCELJsonUtil.objectFromJson(json.get("value"), context);
        if (o instanceof Number) {
            return new IsGreaterOrEqualThan(json.get("attribute").getAsString(), (Number) o);
        }
        throw new IllegalArgumentException();
    }

    private HasValue doDeserializeHasValuePredicate(JsonObject json, JsonDeserializationContext context) {
        return new HasValue(json.get("attribute").getAsString(),
                SCELJsonUtil.objectFromJson(json.get("value"), context));
    }

    private IsGreaterThan doDeserializeIsGreaterThanPredicate(JsonObject json, JsonDeserializationContext context) {
        Object o = SCELJsonUtil.objectFromJson(json.get("value"), context);
        if (o instanceof Number) {
            return new IsGreaterThan(json.get("attribute").getAsString(), (Number) o);
        }
        throw new IllegalArgumentException();
    }

    private IsLessThan doDeserializeIsLessThanPredicate(JsonObject json, JsonDeserializationContext context) {
        Object o = SCELJsonUtil.objectFromJson(json.get("value"), context);
        if (o instanceof Number) {
            return new IsLessThan(json.get("attribute").getAsString(), (Number) o);
        }
        throw new IllegalArgumentException();
    }

    private IsLessOrEqualThan doDeserializeIsLessOrEqualThanPredicate(JsonObject json,
            JsonDeserializationContext context) {
        Object o = SCELJsonUtil.objectFromJson(json.get("value"), context);
        if (o instanceof Number) {
            return new IsLessOrEqualThan(json.get("attribute").getAsString(), (Number) o);
        }
        throw new IllegalArgumentException();
    }
}