Application: gvSIG desktop

/**

 * gvSIG. Desktop Geographic Information System.

 *

 * Copyright (C) 2007-2020 gvSIG Association.

 *

 * This program is free software; you can redistribute it and/or

 * modify it under the terms of the GNU General Public License

 * as published by the Free Software Foundation; either version 3

 * of the License, or (at your option) any later version.

 *

 * This program is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

 * GNU General Public License for more details.

 *

 * You should have received a copy of the GNU General Public License

 * along with this program; if not, write to the Free Software

 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,

 * MA  02110-1301, USA.

 *

 * For any additional information, do not hesitate to contact us

 * at info AT gvsig.com, or visit our website www.gvsig.com.

 */

package org.gvsig.expressionevaluator.impl.coercion;

import java.io.StringWriter;

import java.io.Writer;

import javax.json.Json;

import javax.json.JsonObject;

import javax.json.JsonWriter;

import org.gvsig.tools.dataTypes.AbstractCoercion;

import org.gvsig.tools.dataTypes.CoercionException;

import org.gvsig.tools.dataTypes.CoercionContext;

/**

 * Convert a Expression to String.

 *

 */

public class CoerceJsonObjectToString extends AbstractCoercion {

  public CoerceJsonObjectToString() {

    // Do nothing

  }

  @Override

  public Object coerce(Object value, CoercionContext context) throws CoercionException {

    if (value == null || value instanceof String) {

      return value;

    }

    try {

      if (value instanceof JsonObject ) {

          Writer sw = new StringWriter();

          JsonWriter jsonwriter = Json.createWriter(sw);

          jsonwriter.writeObject((JsonObject) value);

          return sw.toString();

      }

    } catch (Exception e) {

      throw new CoercionException(e);

    }

    throw new CoercionException();

  }

}