Application: gvSIG desktop

/* gvSIG. Geographic Information System of the Valencian Government

 *

 * Copyright (C) 2007-2008 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 2

 * 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.fmap.dal.store.dbf.utils;

import java.io.IOException;

import java.nio.ByteBuffer;

import java.nio.MappedByteBuffer;

import java.nio.channels.FileChannel;

import java.nio.charset.Charset;

import java.text.FieldPosition;

import java.text.NumberFormat;

import java.util.Calendar;

import java.util.Date;

import java.util.Iterator;

import java.util.Locale;

import org.gvsig.fmap.dal.DataTypes;

import org.gvsig.fmap.dal.exception.CloseException;

import org.gvsig.fmap.dal.exception.InitializeException;

import org.gvsig.fmap.dal.exception.UnsupportedEncodingException;

import org.gvsig.fmap.dal.exception.WriteException;

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

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

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

/**

 * A DbaseFileReader is used to read a dbase III format file. The general use of

 * this class is: <CODE><PRE>

 * DbaseFileHeader header = ...

 * WritableFileChannel out = new FileOutputStream("thefile.dbf").getChannel();

 * DbaseFileWriter w = new DbaseFileWriter(header,out);

 * while ( moreRecords ) {

 *   w.write( getMyRecord() );

 * }

 * w.close();

 * </PRE></CODE> You must supply the <CODE>moreRecords</CODE> and

 * <CODE>getMyRecord()</CODE> logic...

 * 

 * @author Ian Schneider

 */

public class DbaseFileWriter {

    private DbaseFileHeader header;

    private DbaseFileWriter.FieldFormatter formatter =

        new DbaseFileWriter.FieldFormatter();

    FileChannel channel;

    private ByteBuffer buffer;

    // private final Number NULL_NUMBER = new Integer(0);

    private final String NULL_STRING = "";

    private final String NULL_DATE = "        ";

    private boolean headDrity = false;

    // TODO: READ HEADER AND STABLIST THE RIGHT CHARSET

    private Charset charset = Charset.forName("ISO-8859-1");

    /**

     * Create a DbaseFileWriter using the specified header and writing to the

     * given channel.

     * 

     * @param header

     *            The DbaseFileHeader to write.

     * @param out

     *            The Channel to write to.

     * 

     * 

     * @throws InitializeWriterException

     * @throws IOException

     *             If errors occur while initializing.

     */

    public DbaseFileWriter(DbaseFileHeader header, FileChannel out,

        boolean isNew) throws InitializeException {

        this.header = header;

        this.channel = out;

        this.headDrity = isNew;

        init();

    }

    private void init() throws InitializeException {

        try {

            if (this.channel.size() < this.header.getHeaderLength()) {

                this.writeHeader();

            }

            buffer = ByteBuffer.allocateDirect(header.getRecordLength());

        } catch (Exception e) {

            throw new InitializeException("DBF Writer", e);

        }

    }

    private void write() throws WriteException {

        buffer.position(0);

        int r = buffer.remaining();

        try {

            while ((r -= channel.write(buffer)) > 0) {

                ; // do nothing

            }

        } catch (IOException e) {

            throw new WriteException("DBF Writer", e);

        }

    }

    private void writeHeader() throws WriteException {

        try {

            channel.position(0);

            header.writeHeader(channel);

        } catch (IOException e) {

            throw new WriteException("DBF Writer", e);

        }

    }

    /**

     * Write a single dbase record.

     * 

     * @param record

     *            The entries to write.

     * @throws UnsupportedEncodingException

     * @throws WriteException

     */

    public void append(Feature feature) throws WriteException,

        UnsupportedEncodingException {

        this.fillBuffer(feature);

        try {

            this.moveToEOF();

        } catch (IOException e) {

            throw new WriteException("DbaseFileWriter", e);

        }

        this.header.setNumRecords(this.header.getNumRecords() + 1);

        write();

        this.headDrity = true;

    }

    private void fillBuffer(Feature feature)

        throws UnsupportedEncodingException, WriteException {

        FeatureType featureType = feature.getType();

        try {

            buffer.position(0);

            // put the 'not-deleted' marker

            buffer.put((byte) ' ');

            @SuppressWarnings("unchecked")

            Iterator<FeatureAttributeDescriptor> iterator =

                featureType.iterator();

            while (iterator.hasNext()) {

                FeatureAttributeDescriptor fad = iterator.next();

                if (fad.getName().length() > DbaseFile.MAX_FIELD_NAME_LENGTH) {

                    throw new FieldNameTooLongException(

                        "DBF file", fad.getName());

                }

                int type = fad.getType();

                if (type == DataTypes.GEOMETRY) {

                    continue;

                }

                String fieldString = fieldString(fad, feature);

                if (fieldString == null) {

                    if (type == DataTypes.STRING) {

                        fieldString = NULL_STRING;

                    } else

                        if (type == DataTypes.DATE) {

                            fieldString = NULL_DATE;

                        } else {

                            fieldString = "0";

                        }

                }

                try {

                    buffer.put(fieldString.getBytes(charset.name()));

                } catch (java.io.UnsupportedEncodingException e) {

                    throw new UnsupportedEncodingException(e);

                }

            }

        } catch (Exception e) {

            throw new WriteException("DbaseFileWriter", e);

        }

    }

    private void moveToEOF() throws IOException {

        this.moveTo(this.header.getNumRecords());

    }

    private void moveTo(long numReg) throws IOException {

        // if (!(channel instanceof FileChannel)) {

        // throw new IOException(

        // "DbaseFileWriterNIO: channel is not a FileChannel. Cannot position properly");

        // }

        long newPos =

            header.getHeaderLength() + numReg * header.getRecordLength();

        if (this.channel.position() != newPos) {

            this.channel.position(newPos);

        }

    }

    /**

     * Write a single dbase record. Useful to update a dbf.

     * 

     * @param record

     *            The entries to write.

     * @throws WriteException

     * @throws UnsupportedEncodingException

     */

    public void update(Feature feature, long numReg) throws WriteException,

        UnsupportedEncodingException {

        this.fillBuffer(feature);

        try {

            this.moveTo(numReg);

        } catch (IOException e) {

            throw new WriteException("DbaseFileWriter", e);

        }

        write();

    }

    private String fieldString(FeatureAttributeDescriptor attr, Feature feature) {

        int type = attr.getType();

        int dbfFieldIndex = this.header.getFieldIndex(attr.getName());

        final int fieldLen = header.getFieldLength(dbfFieldIndex);

        String fieldString = "";

        if (DataTypes.BOOLEAN == type) {

            boolean b = feature.getBoolean(attr.getIndex());

            if (b) {

                fieldString = "T";

            } else {

                fieldString = "F";

            }

        } else

            if (DataTypes.BYTE == type) {

                fieldString = String.valueOf(feature.getByte(attr.getIndex()));

            } else

                if (DataTypes.DATE == type) {

                    Date date = feature.getDate(attr.getIndex());

                    fieldString = formatter.getFieldString(date);

                } else

                    if (DataTypes.DOUBLE == type) {

                        double d = feature.getDouble(attr.getIndex());

                        fieldString =

                            formatter.getFieldString(fieldLen,

                                header.getFieldDecimalCount(dbfFieldIndex), d);

                    } else

                        if (DataTypes.FLOAT == type) {

                            float f = feature.getFloat(attr.getIndex());

                            fieldString =

                                formatter.getFieldString(fieldLen,

                                    header.getFieldDecimalCount(dbfFieldIndex),

                                    f);

                        } else

                            if (DataTypes.INT == type) {

                                int integer = feature.getInt(attr.getIndex());

                                fieldString =

                                    formatter.getFieldString(fieldLen, header

                                        .getFieldDecimalCount(dbfFieldIndex),

                                        integer);

                            } else

                                if (DataTypes.LONG == type) {

                                    long l = feature.getLong(attr.getIndex());

                                    fieldString =

                                        formatter

                                            .getFieldString(

                                                fieldLen,

                                                header

                                                    .getFieldDecimalCount(dbfFieldIndex),

                                                l);

                                } else

                                    if (DataTypes.STRING == type) {

                                        String s =

                                            feature.getString(attr.getIndex());

                                        fieldString =

                                            formatter.getFieldString(fieldLen,

                                                s);

                                    }

        return fieldString;

    }

    // private String fieldString(Object obj,final int col) {

    // String o;

    // final int fieldLen = header.getFieldLength(col);

    // switch (header.getFieldType(col)) {

    // case 'C':

    // case 'c':

    // o = formatter.getFieldString(

    // fieldLen,

    // (obj instanceof NullValue)? NULL_STRING : ((StringValue) obj).getValue()

    // );

    // break;

    // case 'L':

    // case 'l':

    // o = (obj instanceof NullValue) ? "F" : ((BooleanValue)obj).getValue() ==

    // true ? "T" : "F";

    // break;

    // case 'M':

    // case 'G':

    // o = formatter.getFieldString(

    // fieldLen,

    // (obj instanceof NullValue) ? NULL_STRING : ((StringValue) obj).getValue()

    // );

    // break;

    // /* case 'N':

    // case 'n':

    // // int?

    // if (header.getFieldDecimalCount(col) == 0) {

    //

    // o = formatter.getFieldString(

    // fieldLen, 0, (Number) (obj == null ? NULL_NUMBER :

    // Double.valueOf(obj.toString()))

    // );

    // break;

    //

    // }

    // */

    // case 'N':

    // case 'n':

    // case 'F':

    // case 'f':

    // Number number = null;

    // if(obj instanceof NullValue){

    // number = NULL_NUMBER;

    // }else{

    // NumericValue gVal = (NumericValue) obj;

    // number = new Double(gVal.doubleValue());

    // }

    // o = formatter.getFieldString(fieldLen,

    // header.getFieldDecimalCount(col),

    // number);

    // break;

    // case 'D':

    // case 'd':

    // if (obj instanceof NullValue)

    // o = NULL_DATE;

    // else

    // o = formatter.getFieldString(((DateValue)obj).getValue());

    // break;

    // default:

    // throw new RuntimeException("Unknown type " + header.getFieldType(col));

    // }

    //

    // return o;

    // }

    /**

     * Release resources associated with this writer. <B>Highly recommended</B>

     * 

     * @throws CloseException

     * @throws IOException

     *             If errors occur.

     */

    public void close() throws CloseException {

        // IANS - GEOT 193, bogus 0x00 written. According to dbf spec, optional

        // eof 0x1a marker is, well, optional. Since the original code wrote a

        // 0x00 (which is wrong anyway) lets just do away with this :)

        // - produced dbf works in OpenOffice and ArcExplorer java, so it must

        // be okay.

        // buffer.position(0);

        // buffer.put((byte) 0).position(0).limit(1);

        // write();

        if (headDrity) {

            try {

                this.writeHeader();

            } catch (WriteException e) {

                throw new CloseException("DbaseFileWriter", e);

            }

        }

        try {

            channel.close();

        } catch (IOException e) {

            throw new CloseException("DBF Writer", e);

        }

        if (buffer instanceof MappedByteBuffer) {

            // NIOUtilities.clean(buffer);

        }

        buffer = null;

        channel = null;

        formatter = null;

    }

    /** Utility for formatting Dbase fields. */

    public static class FieldFormatter {

        private StringBuffer buffer = new StringBuffer(255);

        private NumberFormat numFormat = NumberFormat

            .getNumberInstance(Locale.US);

        private Calendar calendar = Calendar.getInstance(Locale.US);

        private String emtpyString;

        private static final int MAXCHARS = 255;

        public FieldFormatter() {

            // Avoid grouping on number format

            numFormat.setGroupingUsed(false);

            // build a 255 white spaces string

            StringBuffer sb = new StringBuffer(MAXCHARS);

            sb.setLength(MAXCHARS);

            for (int i = 0; i < MAXCHARS; i++) {

                sb.setCharAt(i, ' ');

            }

            emtpyString = sb.toString();

        }

        public String getFieldString(int size, String s) {

            buffer.replace(0, size, emtpyString);

            buffer.setLength(size);

            if (s != null) {

                buffer.replace(0, size, s);

                if (s.length() <= size) {

                    for (int i = s.length(); i < size; i++) {

                        buffer.append(' ');

                    }

                }

            }

            buffer.setLength(size);

            return buffer.toString();

        }

        public String getFieldString(Date d) {

            if (d != null) {

                buffer.delete(0, buffer.length());

                calendar.setTime(d);

                int year = calendar.get(Calendar.YEAR);

                int month = calendar.get(Calendar.MONTH) + 1; // returns 0 based

                                                              // month?

                int day = calendar.get(Calendar.DAY_OF_MONTH);

                if (year < 1000) {

                    if (year >= 100) {

                        buffer.append("0");

                    } else

                        if (year >= 10) {

                            buffer.append("00");

                        } else {

                            buffer.append("000");

                        }

                }

                buffer.append(year);

                if (month < 10) {

                    buffer.append("0");

                }

                buffer.append(month);

                if (day < 10) {

                    buffer.append("0");

                }

                buffer.append(day);

            } else {

                buffer.setLength(8);

                buffer.replace(0, 8, emtpyString);

            }

            buffer.setLength(8);

            return buffer.toString();

        }

        public String getFieldString(int size, int decimalPlaces, double n) {

            buffer.delete(0, buffer.length());

            // if (n != null) {

            numFormat.setMaximumFractionDigits(decimalPlaces);

            numFormat.setMinimumFractionDigits(decimalPlaces);

            numFormat.format(n, buffer, new FieldPosition(

                NumberFormat.INTEGER_FIELD));

            // }

            int diff = size - buffer.length();

            if (diff >= 0) {

                while (diff-- > 0) {

                    buffer.insert(0, ' ');

                }

            } else {

                buffer.setLength(size);

            }

            return buffer.toString();

        }

    }

    public void setCharset(Charset charset) {

        this.charset = charset;

    }

}