Application: gvSIG desktop

package com.hardcode.gdbms.engine.data.file;

import java.io.File;

import java.io.IOException;

import java.sql.Types;

import com.hardcode.driverManager.Driver;

import com.hardcode.driverManager.DriverLoadException;

import com.hardcode.gdbms.engine.data.SourceInfo;

import com.hardcode.gdbms.engine.data.driver.DriverException;

import com.hardcode.gdbms.engine.data.driver.FileDriver;

import com.hardcode.gdbms.engine.data.driver.GDBMSDriver;

import com.hardcode.gdbms.engine.data.driver.ReadAccess;

import com.hardcode.gdbms.engine.data.edition.DataWare;

import com.hardcode.gdbms.engine.values.Value;

import com.hardcode.gdbms.engine.values.ValueFactory;

/**

 * Adapta la interfaz FileDriver a la interfaz DataSource

 * 

 * @author Fernando Gonz?lez Cort?s

 */

class FileDataSourceAdapter extends AbstractFileDataSource implements

                FileDataSource {

        private File file;

        private FileDriver driver;

        private int sem = 0;

        private int fieldCount = -1;

        /**

         * @see com.hardcode.gdbms.engine.data.DataSource#start()

         */

        public void start() throws DriverException {

                try {

                        if (sem == 0) {

                                driver.open(file);

                        }

                        sem++;

                } catch (IOException e) {

                        throw new DriverException(e);

                }

        }

        /**

         * @see com.hardcode.gdbms.engine.data.DataSource#stop()

         */

        public void stop() throws DriverException {

                try {

                        sem--;

                        if (sem == 0) {

                                driver.close();

                        } else if (sem < 0) {

                                sem=0;

                                driver.close();

                                throw new RuntimeException("DataSource closed too many times");

                        }

                } catch (IOException e) {

                        throw new DriverException(e);

                }

        }

        /**

         * Asigna el driver al adaptador

         * 

         * @param driver

         *            The driver to set.

         */

        public void setDriver(FileDriver driver) {

                this.driver = driver;

        }

        /**

         * Sets the source information of the DataSource

         * 

         * @param sourceInfo

         *            The file to set.

         */

        public void setSourceInfo(SourceInfo sourceInfo) {

                super.setSourceInfo(sourceInfo);

                file = new File(((FileSourceInfo) sourceInfo).file);

        }

        /**

         * @see com.hardcode.gdbms.engine.data.DataSource#getDriver()

         */

        public ReadAccess getReadDriver() {

                return driver;

        }

        /**

         * @see com.hardcode.gdbms.engine.data.DataSource#getName()

         */

        public String getName() {

                return sourceInfo.name;

        }

        /**

         * @see com.hardcode.gdbms.engine.data.DataSource#getPrimaryKeys()

         */

        public int[] getPrimaryKeys() throws DriverException {

                // The last field is the pk/row in FileDataSources

                return new int[] { getFieldCount() - 1 };

        }

        /**

         * @see com.hardcode.gdbms.engine.data.driver.ObjectDriver#getFieldCount()

         */

        public int getFieldCount() throws DriverException {

                if (fieldCount == -1) {

                        fieldCount = getReadDriver().getFieldCount() + 1;

                }

                return fieldCount;

        }

        /**

         * @see com.hardcode.gdbms.engine.data.driver.ObjectDriver#getFieldName(int)

         */

        public String getFieldName(int fieldId) throws DriverException {

                // last field is the virtual primary key

                if (fieldId == getFieldCount() - 1)

                        return "PK";

                return getReadDriver().getFieldName(fieldId);

        }

        /**

         * @see com.hardcode.gdbms.engine.data.driver.ObjectDriver#getFieldType(int)

         */

        public int getFieldType(int i) throws DriverException {

                // last field is the virtual primary key

                if (i == getFieldCount() - 1)

                        return Types.BIGINT;

                return getReadDriver().getFieldType(i);

        }

        /**

         * @see com.hardcode.gdbms.engine.data.driver.ObjectDriver#getFieldValue(long,

         *      int)

         */

        public Value getFieldValue(long rowIndex, int fieldId)

                        throws DriverException {

                // last field is the virtual primary key

                if (fieldId == getFieldCount() - 1)

                        return ValueFactory.createValue(rowIndex);

                Value v = getReadDriver().getFieldValue(rowIndex, fieldId);

                return (v == null) ? ValueFactory.createNullValue() : v;

        }

        /**

         * @see com.hardcode.gdbms.engine.data.file.FileDataSource#getDriver()

         */

        public Driver getDriver() {

                return driver;

        }

        /**

         * @throws DriverException 

         * @see com.hardcode.gdbms.engine.data.DataSource#getDataWare(int)

         */

        public DataWare getDataWare(int mode) throws DriverException {

                try {

                        FileDataWare dw = FileDataSourceFactory.newDataWareInstance();

                        FileDriver driver;

                        driver = (FileDriver) getDataSourceFactory().getDriverManager()

                                        .getDriver(getDriver().getName());

                        ((GDBMSDriver) driver).setDataSourceFactory(getDataSourceFactory());

                        dw.setDriver(driver);

                        dw.setDataSourceFactory(dsf);

                        dw.setSourceInfo(getSourceInfo());

                        return dw;

                } catch (DriverLoadException e) {

                        throw new DriverException(e);

                }

        }

        public int getFieldWidth(int i) throws DriverException {                

                return getReadDriver().getFieldWidth(i);

        }

    public boolean isVirtualField(int fieldId) throws DriverException {

                // last field is the virtual primary key

                if (fieldId == this.getFieldCount() - 1)

                        return true;                

                return false;

    }

        public void reload() throws DriverException {

                try {

                        sem = 0;                

                        driver.close();

                } catch (IOException e) {

                        throw new DriverException(e);

                }

                this.fieldCount = -1;

                this.start();

                this.raiseEventReloaded();

        }

}