platform/sensinact-application/basic-plugin/src/main/java/org/eclipse/sensinact/gateway/app/basic/string/ConcatenateFunction.java

/*
* Copyright (c) 2020 Kentyou.
 * 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:
*    Kentyou - initial API and implementation
 */
package org.eclipse.sensinact.gateway.app.basic.string;

import org.eclipse.sensinact.gateway.app.api.function.DataItf;
import org.json.JSONObject;
import org.json.JSONTokener;
import org.osgi.framework.BundleContext;

import java.io.IOException;
import java.io.InputStreamReader;
import java.util.List;

/**
 * This class implements the concatenate function
 *
 * @author Remi Druilhe
 * @see StringFunction
 */
public class ConcatenateFunction extends StringFunction<String> {
    private static final String JSON_SCHEMA = "concatenate.json";

    /**
     * Gets the JSON schema of the function from the plugin
     *
     * @param context the context of the bundle
     * @return the JSON schema of the function
     */
    public static JSONObject getJSONSchemaFunction(BundleContext context) {
        try {
            return new JSONObject(new JSONTokener(new InputStreamReader(context.getBundle().getResource("/" + JSON_SCHEMA).openStream())));
        } catch (IOException e) {
            e.printStackTrace();
        }
        return null;
    }

    /**
     * @see AbstractFunction#process(List)
     */
    public void process(List<DataItf> datas) {
        StringBuilder sb = new StringBuilder();
        for (DataItf data : datas) {
            sb.append(data.getValue());
        }
        super.update(sb.toString());
    }
}