Application: gvSIG desktop

package org.gvsig.fmap.dal.feature.impl.dynobjectutils.relations;

import org.gvsig.fmap.dal.DALLocator;

import org.gvsig.fmap.dal.DataManager;

import org.gvsig.fmap.dal.DataStoreParameters;

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

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

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

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

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

import org.gvsig.fmap.dal.feature.paging.FeaturePagingHelper;

import org.gvsig.tools.dataTypes.CoercionException;

import org.gvsig.tools.dynobject.AbstractDynMethod;

import org.gvsig.tools.dynobject.DynField_v2;

import org.gvsig.tools.dynobject.DynObject;

import org.gvsig.tools.dynobject.exception.DynMethodException;

import org.gvsig.tools.dynobject.exception.DynMethodNotSupportedException;

public class DALLink_getRelatedFeatures extends AbstractDynMethod {

    private static final String DAL_code = "DAL.code";

    private static final String DAL_foreingTable = "DAL.foreingTable";

    private static final String DAL_foreingCode = "DAL.foreingCode";

    private static final String DAL_pageSize = "DAL.pageSize";

    public DALLink_getRelatedFeatures() {

        super("DAL.getRelatedFeatures","Retrieve a list with al elements related to this object.");

    }

    public Object invoke(DynObject self, Object[] args) throws DynMethodException {

        if (!(self instanceof FacadeOfAFeature)) {

            return null;

        }

        DynField_v2 field = (DynField_v2) args[0];

        String foreignCodeName = (String) field.getTags().get(DAL_foreingCode);

        String foreignTableName = (String) field.getTags().get(DAL_foreingTable);

        String codeName = (String) field.getTags().get(DAL_code);

        int pageSize;

        try {

            pageSize = field.getTags().getInt(DAL_pageSize);

        } catch (CoercionException ex) {

            pageSize = 100;

        }

        if (pageSize < 100) {

            pageSize = 100;

        }

        Feature feature = ((FacadeOfAFeature) self).getFeature();

        FeaturePagingHelper featurePager = getRelatedFeatures(feature, codeName, foreignTableName, foreignCodeName, pageSize);

        return featurePager.asListOfDynObjects();

    }

    private FeaturePagingHelper getRelatedFeatures(Feature feature, String codeName, String foreignTableName, String foreignCodeName, int pageSize) throws ComputeRelatedFeaturesException {

        Object fkValue = "<unknow>";

        try {

            FeatureStore store = feature.getStore();

            DataManager manager = DALLocator.getDataManager();

            FeatureAttributeDescriptor attrdesc = feature.getType().getAttributeDescriptor(codeName);

            DataStoreParameters foreignStoreParmeters = store.getExplorer().get(foreignTableName);

            FeatureStore foreignStore = (FeatureStore) manager.openStore(store.getProviderName(), foreignStoreParmeters);

            FeatureQuery query = foreignStore.createFeatureQuery();

            fkValue = feature.get(codeName);

            if (attrdesc.getDataType().isNumeric()) {

                fkValue = fkValue.toString();

            } else {

                fkValue = "'" + fkValue.toString().replace("'", "''") + "'";

            }

            String where = foreignCodeName + " = " + fkValue;

            query.addFilter(manager.createExpresion(where));

            FeaturePagingHelper featurePager = manager.createFeaturePagingHelper(foreignStore, query, pageSize);

            return featurePager;

        } catch (Exception ex) {

            throw new ComputeRelatedFeaturesException(foreignTableName, foreignCodeName, fkValue.toString(), ex);

        }

    }

    private static class ComputeRelatedFeaturesException extends DynMethodException {

        private final static String MESSAGE_FORMAT = "Can't retrieve relation items from %(storename)s for attribute %(attrname)s with value %(attrvalue)s.";

        private final static String MESSAGE_KEY = "_OneToManyMethodException";

        private static final long serialVersionUID = -3248317756866564508L;

        public ComputeRelatedFeaturesException(String storename, String attrname, String attrvalue, Throwable cause) {

            super(MESSAGE_FORMAT, MESSAGE_KEY, serialVersionUID);

            setValue("storename", storename);

            setValue("attrname", attrname);

            setValue("attrvalue", attrvalue);

            this.initCause(cause);

        }

    }

}