Application: gvSIG desktop

/**

 * gvSIG. Desktop Geographic Information System.

 *

 * Copyright (C) 2007-2013 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.

 */

/*

 * AUTHORS (In addition to CIT):

 * 2008 {DiSiD Technologies}  {Create Parameter object to define FeatureCollections queries}

 */

package org.gvsig.fmap.dal.feature;

import java.util.List;

import java.util.Map;

import org.gvsig.expressionevaluator.Expression;

import org.gvsig.expressionevaluator.MutableSymbolTable;

import org.gvsig.expressionevaluator.SymbolTable;

import org.gvsig.fmap.dal.DataQuery;

import org.gvsig.tools.evaluator.Evaluator;

import org.gvsig.tools.lang.Cloneable;

/**

 * Defines the properties of a collection of Features, as a result of a query

 * through a FeatureStore.

 * <p>

 * A FeatureQuery is always defined by a FeatureType, or by the list of

 * attribute names of the FeatureStore to return.

 * </p>

 * <p>

 * The filter allows to select Features whose properties have values with the

 * characteristics defined by the filter.

 * </p>

 * <p>

 * The order is used to set the order of the result FeatureCollection, based on

 * the values of the properties of the Features.

 * </p>

 * <p>

 * The scale parameter can be used by the FeatureStore as a hint about the

 * quality or resolution of the data needed to view or operate with the data

 * returned. As an example, the FeatureStore may use the scale to return only a

 * representative subset of the data, or maybe to return Features with less

 * detail, like a point or a line instead of a polygon.

 * </p>

 * <p>

 * If an implementation of FeatureStore is able to get other parameters to

 * customize the behavior of the getDataCollection methods, there is an option

 * to set more parameters through the setAttribute method.

 * </p>

 *

 * @author 2009- <a href="cordinyana@gvsig.org">C?sar Ordi?ana</a> - gvSIG team

 */

public interface FeatureQuery extends DataQuery, Cloneable {

  /**

   * Returns the names of the attributes to load from each {@link Feature}.

   *

   * @return the attribute names to load

   */

  String[] getAttributeNames();

  /**

   * Sets the names of the attributes to load from each {@link Feature}.

   *

   * @param attributeNames the attribute names to load

   */

  void setAttributeNames(String[] attributeNames);

  void retrievesAllAttributes();

  /**

   * Adds the name of an attribute that has to be used to load each

   * {@link Feature}.

   *

   * @param attributeName the attribute name to load

   */

  void addAttributeName(String attributeName);

  public void addPrimaryKeyAttributeNames(FeatureStore store);

  public void addEssentialAttributeNames(FeatureStore store);

  /**

   * Return true if has set attribute names

   *

   * @return true if has attribute names, otherwise false

   */

  boolean hasAttributeNames();

  /**

   * Remove all the attribute names specifieds.

   */

  void clearAttributeNames();

  /**

   * Returns the names of the attributes that are constants in each

   * {@link Feature}. These attributes will not be charged.

   *

   * @return the attribute names that are constant

   */

  String[] getConstantsAttributeNames();

  /**

   * Set of attribute names to be treated as constants for each {@link Feature}.

   *

   * @param attributeNames the attribute names to be constants

   */

  void setConstantsAttributeNames(String[] attributeNames);

  /**

   * Add an attribute name that will be treated as constant for each

   * {@link Feature}.

   *

   * @param attributeName the attribute name to be treated as constant

   */

  void addConstantAttributeName(String attributeName);

  /**

   * Return true if has set constants attribute names

   *

   * @return true if has constants attribute names, otherwise false

   */

  boolean hasConstantsAttributeNames();

  /**

   * Remove all the names specified as constants attributes.

   */

  void clearConstantsAttributeNames();

  /**

   * Sets the {@link FeatureType} of the {@link Feature}s to load. It may be

   * used as an alternative way to set a subset of the list of attribute names

   * to load, by creating a sub-FeatureType.

   *

   * @param featureType the feature type of the data to load

   */

  void setFeatureType(FeatureType featureType);

  /**

   * Returns the {@link FeatureType} id of the {@link Feature}s to load.

   *

   * @return the {@link FeatureType} id of the {@link Feature}s to load

   */

  String getFeatureTypeId();

  /**

   * Sets the {@link FeatureType} id of the {@link Feature}s to load. This way

   * all {@link Feature} attributes will be loaded.

   *

   * @param featureTypeId the {@link FeatureType} id of the {@link Feature}s to

   * load

   */

  void setFeatureTypeId(String featureTypeId);

  /**

   * Returns the filter to apply to the {@link Feature}s to load.

   *

   * @return the filter

   */

  Evaluator getFilter();

  /** 

   * Return the Expression associated to the filter.

   * If the current filter is not an Expression, return null.

   * 

   * @return the expression of the filter.

   */

  Expression getExpressionFilter();

  /**

   * Sets the filter to apply to the {@link Feature}s to load.

   *

   * @param filter the filter to apply to the {@link Feature}s to load

   */

  void setFilter(Evaluator filter);

  void setFilter(Expression filter);

  void setFilter(String filter);

  /**

   * Adds a filter to apply to the {@link Feature}s to load. A query can have

   * more that one filter and all of them are applied when the query is applied.

   * If filter is null do nothing.

   *

   * @param filter a filter to apply to the {@link Feature}s to load

   */

  void addFilter(Evaluator filter);

  void addFilter(Expression filter);

  void addFilter(String filter);

  void clearFilter();

  /**

   * Returns if a filter has been defined for the query.

   *

   * @return if a filter has been defined for the query

   */

  boolean hasFilter();

  /**

   * Returns the order of the {@link Feature}s to load.

   *

   * @return the order of the {@link Feature}s to load

   */

  FeatureQueryOrder getOrder();

  /**

   * Sets the order of the {@link Feature}s to load.

   *

   * @param order the order of the {@link Feature}s to load

   */

  void setOrder(FeatureQueryOrder order);

  /**

   * Returns if an order has been set for the elements returned by the query.

   *

   * @return if an order has been set for the elements returned by the query

   */

  boolean hasOrder();

  /**

   * @return @deprecated to be removed in gvSIG 2.0

   * @see #clone()

   */

  FeatureQuery getCopy();

  /**

   * Returns the maximum number of elements to return with this query.

   * <p>

   * <strong>NOTE:</strong> this value may be ignored by the underlying data

   * source, or only used as a hint, so don't rely on it being used, as you may

   * actually get more values than the limit.

   * </p>

   *

   * @return the maximum number of elements to return with this query

   */

  long getLimit();

  /**

   * Sets the maximum number of elements to return with this query.

   * <p>

   * <strong>NOTE:</strong> this value may be ignored by the underlying data

   * source, or only used as a hint, so don't rely on it being used, as you may

   * actually get more values than the limit.

   * </p>

   *

   * @param limit the maximum number of elements to return with this query

   */

  void setLimit(long limit);

  /**

   * Returns the load page size, as the number of elements to be retrieved in

   * block by the data source. This value is only used as a hint to the

   * underlying data source, as a way to tell how many Features may be read in a

   * block.

   *

   * @return the load page size

   */

  long getPageSize();

  /**

   * Sets the load page size, as the number of elements to be retrieved in block

   * by the data source. This value is only used as a hint to the underlying

   * data source, as a way to tell how many Features may be read in a block.

   *

   * @param pageSize the load page size

   */

  void setPageSize(long pageSize);

  /**

   * Returns true if a subquery should be used. It will only take effect 

   * when the sql perameter of the connection has a value. 

   * @return 

   */

  public boolean isUseSubquery();

  /**

   * Indicates whether to use a subquery or not in case the connection has 

   * an sql indicated. This flag will have no effect if the "sql" parameter 

   * in the connection has not been specified.

   * By default it will be true and whenever an sql has been indicated in the 

   * connection, a subquery will be used to access the data. If false is assigned, 

   * the sql should return, in the same order, the rows required by the 

   * FeatureType of the store.

   * 

   * @param useSubquery 

   */

  public void setUseSubquery(boolean useSubquery);

  /**

   * Return the names of attributes for group the features.

   * 

   * @return the list of names to group features.

   */

  public List<String> getGroupByColumns();

  public boolean isAGroupByColumn(String name);

  public boolean hasGroupByColumns();

  /**

   * Return the aggregate functions useds for every attribute of the feature.

   * The map is indexed by the name of the attribute and contains the aggregate 

   * functions used by each attribute.

   * 

   * @return a Map with the aggregate function by attribute

   */

  public Map<String,String> getAggregateFunctions();

  public void addAggregate(String funcName, String columnName);

  @Deprecated

  public String getAggregate(String name);

  public String getAggregate(String tableName, String name);

  public boolean hasAggregateFunctions();

  public void copyFrom(FeatureQuery query);

  public FeatureExtraColumns getExtraColumn();

  public MutableSymbolTable getSymbolTable();

  public void setSymbolTable(MutableSymbolTable symbolTable);

  /**

   * Set a variable in the symbol table associated to this searchPanel.

   * 

   * @param name

   * @param value 

   */

  public void setVar(String name, Object value);

}