| gvSIG desktop 1

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

import java.io.File;

import java.io.FileInputStream;

import java.io.FileOutputStream;

import java.io.IOException;

import com.hardcode.gdbms.engine.data.db.FakeTransactionSupport;

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

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

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

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

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

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

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

/**

 * @author Fernando Gonz?lez Cort?s

 */

public class FileDataWareImpl extends FileDataSourceAdapter implements

        FileDataWare {

    private FakeTransactionSupport ftSupport = new FakeTransactionSupport(this);

    public void start() throws DriverException {

        throw new RuntimeException("Invoke beginTrans in a DataWare");

    }

    public void stop() throws DriverException {

        throw new RuntimeException(

                "Invoke commitTrans/rollBackTrans in a DataWare");

    }

    public void beginTrans() throws DriverException {

        super.start();

        ftSupport.beginTrans();

    }

    public void commitTrans() throws DriverException {

        ((FileDriver)getDriver()).writeFile(this);

        super.stop();

        ftSupport.commitTrans();

    }

    public void copy(File in, File out) throws IOException {

        FileInputStream fis = new FileInputStream(in);

        FileOutputStream fos = new FileOutputStream(out);

        byte[] buf = new byte[1024];

        int i = 0;

        while ((i = fis.read(buf)) != -1) {

            fos.write(buf, 0, i);

        }

        fis.close();

        fos.close();

    }

    public void deleteRow(long rowId) throws DriverException {

        ftSupport.deleteRow(rowId);

    }

    public void insertEmptyRow(ValueCollection pk) throws DriverException {

        ftSupport.insertEmptyRow(pk);

    }

    public void insertFilledRow(Value[] values) throws DriverException {

        ftSupport.insertFilledRow(values);

    }

    public void rollBackTrans() throws DriverException {

        super.stop();

        ftSupport.rollBackTrans();

    }

    public void setFieldValue(long row, int fieldId, Value value)

            throws DriverException {

        ValueCollection pkValue = null;

        Value[] originalRow = null;

        if (row < super.getRowCount()) {

            pkValue = getOriginalPKValue(row);

            originalRow = getOriginalRow(row);

        }

        ftSupport.setFieldValue(row, fieldId, value, pkValue, originalRow);

    }

    /**

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

     *      int)

     */

    public Value getFieldValue(long rowIndex, int fieldId)

            throws DriverException {

        // If there is no transaction

        if (!ftSupport.isTransaction()) {

            return super.getFieldValue(rowIndex, fieldId);

        }

        // get where's the row

        EditionInfo fip = ftSupport.getPKTable().getIndexLocation(

                (int) rowIndex);

        int flag = fip.getFlag();

        // get the value

        if ((flag == PKTable.ADDED) || (flag == PKTable.MODIFIED)) {

            return ftSupport.getInternalBuffer().getFieldValue(fip.getIndex(),

                    fieldId);

        } else {

            return super.getFieldValue(fip.getIndex(), fieldId);

        }

    }

    /**

     * @see com.hardcode.gdbms.engine.data.driver.ReadAccess#getRowCount()

     */

    public long getRowCount() throws DriverException {

        if (ftSupport.isTransaction()) {

            // If there is a transaction

            return ftSupport.getPKTable().getPKCount();

        } else {

            // If there's not

            return super.getRowCount();

        }

    }

    /**

     * Gets the value of the original row

     * 

     * @param rowIndex

     *            index of the row to be retrieved

     * 

     * @return Row values

     * 

     * @throws DriverException

     *             if the operation fails

     */

    private Value[] getOriginalRow(long rowIndex) throws DriverException {

        Value[] ret = new Value[getFieldCount()];

        for (int i = 0; i < ret.length; i++) {

            ret[i] = super.getFieldValue(rowIndex, i);

        }

        return ret;

    }

    /**

     * Gets the primary key value in the original DataSource

     * 

     * @param rowIndex

     *            index of the row to be read

     * 

     * @return PK

     * 

     * @throws DriverException

     *             If the operation fails

     */

    private ValueCollection getOriginalPKValue(long rowIndex)

            throws DriverException {

        int[] fieldsId = getPrimaryKeys();

        Value[] pks = new Value[fieldsId.length];

        for (int i = 0; i < pks.length; i++) {

            pks[i] = super.getFieldValue(rowIndex, fieldsId[i]);

        }

        return ValueFactory.createValue(pks);

    }

}