gvSIG data provider for Sqlite

/* gvSIG. Geographic Information System of the Valencian Government

 *

 * Copyright (C) 2007-2016 Infrastructures and Transports Department

 * of the Valencian Government (CIT)

 *

 * 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.

 *

 */

package org.gvsig.spatialite.dal;

import java.io.File;

import org.gvsig.spatialite.dal.operations.SpatiaLiteOperationsFactory;

import java.sql.Connection;

import java.sql.SQLException;

import java.sql.Statement;

import java.util.Map;

import org.apache.commons.dbcp.BasicDataSource;

import org.apache.commons.io.FilenameUtils;

import org.apache.commons.lang3.StringUtils;

import org.gvsig.fmap.dal.SQLBuilder;

import org.gvsig.fmap.dal.resource.exception.AccessResourceException;

import org.gvsig.fmap.dal.store.jdbc.JDBCConnectionParameters;

import org.gvsig.fmap.dal.store.jdbc.JDBCNewStoreParameters;

import org.gvsig.fmap.dal.store.jdbc.JDBCServerExplorerParameters;

import org.gvsig.fmap.dal.store.jdbc.JDBCStoreParameters;

import org.gvsig.fmap.dal.store.jdbc.exception.JDBCDriverClassNotFoundException;

import org.gvsig.fmap.dal.store.jdbc2.JDBCUtils;

import org.gvsig.fmap.dal.store.jdbc2.OperationsFactory;

import org.gvsig.fmap.dal.store.jdbc2.spi.JDBCHelperBase;

import org.gvsig.fmap.dal.store.jdbc2.spi.JDBCSQLBuilderBase;

import org.gvsig.fmap.dal.store.jdbc2.spi.SRSSolverBase;

import org.gvsig.fmap.geom.Geometry;

import org.gvsig.fmap.geom.aggregate.MultiLine;

import org.gvsig.fmap.geom.aggregate.MultiPoint;

import org.gvsig.fmap.geom.aggregate.MultiPolygon;

import org.gvsig.fmap.geom.exception.CreateGeometryException;

import org.gvsig.fmap.geom.primitive.Primitive;

import org.gvsig.fmap.geom.type.GeometryType;

import org.slf4j.Logger;

import org.slf4j.LoggerFactory;

import org.sqlite.SQLiteConfig;

import org.sqlite.SQLiteConfig.TransactionMode;

public class SpatiaLiteHelper extends JDBCHelperBase {

    static final Logger logger = LoggerFactory.getLogger(SpatiaLiteHelper.class);

    public static final String NAME = "SpatiaLite";

    public static final String SpatiaLiteJDBCDriver = "org.sqlite.JDBC";

    public static final String URL_FORMAT = "jdbc:sqlite:%s";

    public static String getConnectionURL(SpatiaLiteConnectionParameters params) {

        String fname = params.getFile().getAbsolutePath().replace("\\","/");

        if( StringUtils.isEmpty(FilenameUtils.getExtension(fname)) ) {

            fname = fname + ".sqlite";

            params.setFile(new File(fname));

        }

        String driverClassName = params.getJDBCDriverClassName();

        if( StringUtils.isNotBlank(driverClassName) && 

            !StringUtils.equals(driverClassName, SpatiaLiteJDBCDriver) ) {

            try {

                Class.forName(driverClassName);

            } catch(Throwable th) {

                logger.warn("Can't load SpatiaLite JDBC Driver '"+driverClassName+"'.",th);

            }            

        }

        String connectionURLFormat = params.getURLFormat(); 

        if( StringUtils.isBlank(connectionURLFormat) ) {

            connectionURLFormat = URL_FORMAT;

        }

        String connectionURL = String.format(connectionURLFormat, fname);

        logger.debug("connectionURL: {}", connectionURL);

        return connectionURL;

    }

    private static class ConnectionProvider {

        private static boolean needRegisterDriver = true;

        private BasicDataSource dataSource = null;

        private final SpatiaLiteConnectionParameters connectionParameters;

        public ConnectionProvider(SpatiaLiteConnectionParameters connectionParameters) {

            this.connectionParameters = connectionParameters;

        }

        public Connection getConnection() throws SQLException {

                boolean newDB = (connectionParameters.getFile()==null || !connectionParameters.getFile().exists());

            if (this.dataSource == null) {

                this.dataSource = this.createDataSource();               

            }

            Connection conn = this.dataSource.getConnection();

            loadExtension(conn);

            if (newDB) {

                    initSpatialMetadata(conn);

            }

            return conn;

        }

        private BasicDataSource createDataSource() throws SQLException {

            if (!this.isRegistered()) {

                this.registerDriver();

            }

            SpatiaLiteConnectionParameters params = connectionParameters;

            BasicDataSource ds = new BasicDataSource();

            ds.setDriverClassName(params.getJDBCDriverClassName());

            if( !StringUtils.isEmpty(params.getUser()) ) {

                ds.setUsername(params.getUser());

            }

            if( !StringUtils.isEmpty(params.getPassword()) ) {

                ds.setPassword(params.getPassword());

            }

            ds.setUrl(params.getUrl());

            SQLiteConfig config = new SQLiteConfig();

            config.setSharedCache(true);

            config.enableLoadExtension(true);

            config.setTransactionMode(TransactionMode.IMMEDIATE);

            for (Map.Entry e : config.toProperties().entrySet()) {

                ds.addConnectionProperty((String)e.getKey(), (String)e.getValue());

            }

            ds.setMaxWait(60L * 1000);

            return ds;

        }

        private boolean isRegistered() {

            return needRegisterDriver;

        }

        public void registerDriver() throws SQLException {

            String className = this.connectionParameters.getJDBCDriverClassName();

            if (className == null) {

                return;

            }

            try {

                Class theClass = Class.forName(className);

                if (theClass == null) {

                    throw new JDBCDriverClassNotFoundException(NAME, className);

                }

            } catch (Exception e) {

                throw new SQLException("Can't register JDBC driver '" + className + "'.", e);

            }

            needRegisterDriver = false;

        }

        public void loadExtension(Connection conn) {

                    Statement st = null;

            try {

                st = conn.createStatement();

                JDBCUtils.execute(st, "SELECT load_extension('mod_spatialite')");

            } catch(Exception ex) {

                logger.warn("Can't load mod_spatialite extension module for SQLite (" +

                        " driver class "+StringUtils.defaultString(connectionParameters.getJDBCDriverClassName()) +

                        " url format "+StringUtils.defaultString(connectionParameters.getURLFormat()) +

                        " file "+connectionParameters.getFile()==null?"null":connectionParameters.getFile().getAbsolutePath() +

                        ").", ex);

            }

            finally {

                    JDBCUtils.closeQuietly(st);

            }          

        }

        public void initSpatialMetadata(Connection conn) {

                Statement st = null;

                try {

                        st = conn.createStatement();

                        //harmless if already existing

                        JDBCUtils.execute(st, "SELECT InitSpatialMetaData(1)");

                } catch(Exception ex) {

                logger.warn("Can't initialize spatial metatada in SQLite database (" +

                        " driver class "+StringUtils.defaultString(connectionParameters.getJDBCDriverClassName()) +

                        " url format "+StringUtils.defaultString(connectionParameters.getURLFormat()) +

                        " file "+connectionParameters.getFile()==null?"null":connectionParameters.getFile().getAbsolutePath() +

                        ").", ex);

                }

                finally {

                        JDBCUtils.closeQuietly(st);

                }

        }

    }

    private ConnectionProvider connectionProvider = null;

    public SpatiaLiteHelper(JDBCConnectionParameters connectionParameters) {

        super(connectionParameters);

        this.srssolver = new SRSSolverBase(this);

    }

    @Override

    public synchronized Connection  getConnection() throws AccessResourceException {

        try {

            if (this.connectionProvider == null) {

                this.connectionProvider = new ConnectionProvider(this.getConnectionParameters());

            }

            Connection connection = this.connectionProvider.getConnection();

            logger.debug("getConnection: connection = "+connection.hashCode());

            return connection;

        } catch (SQLException ex) {

            throw new AccessResourceException(SpatiaLiteLibrary.NAME, ex);

        }

    }

    @Override

    public SpatiaLiteConnectionParameters getConnectionParameters() {

        return (SpatiaLiteConnectionParameters) super.getConnectionParameters();

    }

    @Override

    public String getConnectionURL() {

        return getConnectionURL(this.getConnectionParameters());

    }

    @Override

    protected String getResourceType() {

        return SpatiaLiteLibrary.NAME;

    }

    @Override

    public String getProviderName() {

        return SpatiaLiteLibrary.NAME;

    }

    @Override

    public JDBCSQLBuilderBase createSQLBuilder() {

        return new SpatiaLiteSQLBuilder(this);

    }

    @Override

    public OperationsFactory getOperations() {

        if (this.operationsFactory == null) {

            this.operationsFactory = new SpatiaLiteOperationsFactory(this);

        }

        return operationsFactory;

    }

    @Override

    public SQLBuilder.GeometrySupportType getGeometrySupportType() {

        return SQLBuilder.GeometrySupportType.WKB;

    }

    @Override

    public boolean hasSpatialFunctions() {

        return true;

    }

    @Override

    public boolean canWriteGeometry(int geometryType, int geometrySubtype) {

        return true;

    }

    @Override

    public String getQuoteForIdentifiers() {

        return "\"";

    }

    @Override

    public boolean allowAutomaticValues() {

        return true;

    }

    @Override

    public boolean supportOffsetInSelect() {

        return true;

    }

    @Override

    public String getQuoteForStrings() {

        return "'";

    }

    @Override

    public String getSourceId(JDBCStoreParameters parameters) {

        return parameters.getDBName() + "." + 

               parameters.getSchema()+ "." + 

               parameters.getTable();

    }

    @Override

    public JDBCNewStoreParameters createNewStoreParameters() {

        return new SpatiaLiteNewStoreParameters();

    }

    @Override

    public JDBCStoreParameters createOpenStoreParameters() {

        return new SpatiaLiteStoreParameters();

    }

    @Override

    public JDBCServerExplorerParameters createServerExplorerParameters() {

        return new SpatiaLiteExplorerParameters();

    }

    public Geometry forceGeometryType(GeometryType geomtype, Geometry geom) throws CreateGeometryException {

        if( geom == null ) {

            return null;

        }

        switch( geomtype.getType() ) {

        case Geometry.TYPES.MULTIPOLYGON:

            if( geom.getType()==Geometry.TYPES.POLYGON ) {

                MultiPolygon x = getGeometryManager().createMultiPolygon(geomtype.getSubType());

                x.addPrimitive((Primitive) geom);

                geom = x;

            }

            break;

        case Geometry.TYPES.MULTILINE:

            if( geom.getType()==Geometry.TYPES.LINE ) {

                MultiLine x = getGeometryManager().createMultiLine(geomtype.getSubType());

                x.addPrimitive((Primitive) geom);

                geom = x;

            }

            break;

        case Geometry.TYPES.MULTIPOINT:

            if( geom.getType()==Geometry.TYPES.POINT ) {

                MultiLine x = getGeometryManager().createMultiLine(geomtype.getSubType());

                x.addPrimitive((Primitive) geom);

                geom = x;

            }

            break;

        case Geometry.TYPES.POLYGON:

            if( geom.getType()==Geometry.TYPES.MULTIPOLYGON ) {

                MultiPolygon x = (MultiPolygon) geom;

                if( x.getPrimitivesNumber()==1 ) {

                    geom = x.getPrimitiveAt(0);

                }

            }

            break;

        case Geometry.TYPES.LINE:

            if( geom.getType()==Geometry.TYPES.MULTILINE ) {

                MultiLine x = (MultiLine) geom;

                if( x.getPrimitivesNumber()==1 ) {

                    geom = x.getPrimitiveAt(0);

                }

            }

            break;

        case Geometry.TYPES.POINT:

            if( geom.getType()==Geometry.TYPES.MULTIPOINT ) {

                MultiPoint x = (MultiPoint) geom;

                if( x.getPrimitivesNumber()==1 ) {

                    geom = x.getPrimitiveAt(0);

                }

            }

        }

        return geom;

    }

}