org.apache.twill.internal.json.StateNodeCodec.java Source code

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Here is the source code for org.apache.twill.internal.json.StateNodeCodec.java

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/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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 org.apache.twill.internal.json;

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;
import com.google.gson.JsonSerializationContext;
import com.google.gson.JsonSerializer;
import org.apache.twill.api.ServiceController;
import org.apache.twill.internal.state.StateNode;

import java.lang.reflect.Type;

/**
 * Gson codec for {@link StateNode}.
 */
public final class StateNodeCodec implements JsonSerializer<StateNode>, JsonDeserializer<StateNode> {

    @Override
    public StateNode deserialize(JsonElement json, Type typeOfT, JsonDeserializationContext context)
            throws JsonParseException {
        JsonObject jsonObj = json.getAsJsonObject();
        ServiceController.State state = ServiceController.State.valueOf(jsonObj.get("state").getAsString());
        String errorMessage = jsonObj.has("errorMessage") ? jsonObj.get("errorMessage").getAsString() : null;

        return new StateNode(state, errorMessage,
                context.<StackTraceElement[]>deserialize(jsonObj.get("stackTraces"), StackTraceElement[].class));
    }

    @Override
    public JsonElement serialize(StateNode src, Type typeOfSrc, JsonSerializationContext context) {
        JsonObject jsonObj = new JsonObject();
        jsonObj.addProperty("state", src.getState().name());
        if (src.getErrorMessage() != null) {
            jsonObj.addProperty("errorMessage", src.getErrorMessage());
        }
        if (src.getStackTraces() != null) {
            jsonObj.add("stackTraces", context.serialize(src.getStackTraces(), StackTraceElement[].class));
        }
        return jsonObj;
    }
}