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.function.dataaccess;

import java.util.Map;

import java.util.Objects;

import org.apache.commons.lang3.Range;

import org.gvsig.expressionevaluator.Codes;

import org.gvsig.expressionevaluator.ExpressionRuntimeException;

import org.gvsig.expressionevaluator.Interpreter;

import org.gvsig.expressionevaluator.impl.DALFunctions;

import org.gvsig.fmap.dal.DataManager;

import org.gvsig.fmap.dal.feature.Feature;

import org.gvsig.tools.util.GetItemByKey;

import org.gvsig.tools.util.GetKeys;

/**

 *

 * @author jjdelcerro

 */

public class RowTagFunction extends AbstractFeatureFunction {

  public RowTagFunction() {

    super(  DALFunctions.GROUP_DATA_ACCESS,

            DataManager.FUNCTION_ROW_TAG,

            Range.between(1,2),

            "Retrieves a value associated with a tag from the current line.\n" +

              "Return null if used outer a table filter or if the row don't " +

              "have a tag with the value indicated.",

            DataManager.FUNCTION_ROW_TAG+"({{name}})",

            null,

            "Object",

            false

    );

  }

  @Override

  public boolean allowConstantFolding() {

    return false;

  }

  @Override

  public boolean useArgumentsInsteadObjects() {

    return true;

  }

  @Override

  public Object call(Interpreter interpreter, Object[] args) throws Exception {

    return null;

  }

  @Override

  public Object call(Interpreter interpreter, Codes args) throws Exception {

    Feature f = this.current_row(interpreter);

    if( f==null ) {

      return null;

    }

    String name = Objects.toString(getObject(interpreter, args, 0),null);

    if( name == null ) {

      throw new ExpressionRuntimeException("The first argument of '"+DataManager.FUNCTION_SET_ROW_TAG+"' can't be null.");    

    }

    if( args.size()==2 ) {

      if( !f.hasExtraValue(name) ) {

        Object map = Objects.toString(getObject(interpreter, args, 1),null);

        if( map instanceof Map) {

          for (Map.Entry<Object, Object> entry : ((Map<Object,Object>)map).entrySet()) {

            String key = Objects.toString(entry.getKey(),null);

            Object val = entry.getValue();

            if( key!=null ) {

              f.setExtraValue(key, val);

            }

          }

        } else if( map instanceof GetItemByKey && map instanceof GetKeys ) {

          for (String key : ((GetKeys<String>)map).getKeys() ) {

            Object val = ((GetItemByKey<String,Object>)map).get(key);

            f.setExtraValue(key, val);

          }

        }

      }

    }

   return f.getExtraValue(name);

  }

}