svn-gvsig-desktop / trunk / libraries / libFMap / src / com / iver / cit / gvsig / fmap / drivers / dbf / DbaseFile.java @ 2891
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/*
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* Created on 16-feb-2004
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*
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* To change the template for this generated file go to
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* Window>Preferences>Java>Code Generation>Code and Comments
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*/
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package com.iver.cit.gvsig.fmap.drivers.dbf; |
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/**
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*/
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import java.io.File; |
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import java.io.FileInputStream; |
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import java.io.IOException; |
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import java.io.RandomAccessFile; |
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import java.nio.ByteBuffer; |
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import java.nio.channels.FileChannel; |
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import com.iver.utiles.bigfile.BigByteBuffer; |
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/**
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* Class to read and write data to a dbase III format file. Creation date:
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* (5/15/2001 5:15:13 PM)
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*/
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public class DbaseFile { |
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// Header information for the DBase File
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private DbaseFileHeader myHeader;
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private RandomAccessFile raf; |
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private FileChannel channel; |
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private BigByteBuffer buffer;
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private FileChannel.MapMode mode; |
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// Retrieve number of records in the DbaseFile
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public int getRecordCount() { |
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return myHeader.getNumRecords();
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} |
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/**
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* DOCUMENT ME!
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*
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* @return DOCUMENT ME!
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*/
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public int getFieldCount() { |
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return myHeader.getNumFields();
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} |
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/**
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* DOCUMENT ME!
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*
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* @param rowIndex DOCUMENT ME!
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* @param fieldId DOCUMENT ME!
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*
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* @return DOCUMENT ME!
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*/
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public boolean getBooleanFieldValue(int rowIndex, int fieldId) { |
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int recordOffset = (myHeader.getRecordLength() * rowIndex) +
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myHeader.getHeaderLength() + 1;
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//Se calcula el offset del campo
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int fieldOffset = 0; |
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for (int i = 0; i < (fieldId - 1); i++) { |
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fieldOffset += myHeader.getFieldLength(i); |
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} |
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buffer.position(recordOffset + fieldOffset); |
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char bool = (char) buffer.get(); |
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return ((bool == 't') || (bool == 'T') || (bool == 'Y') || |
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(bool == 'y'));
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} |
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/**
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* DOCUMENT ME!
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*
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* @param rowIndex DOCUMENT ME!
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* @param fieldId DOCUMENT ME!
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*
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* @return DOCUMENT ME!
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*/
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public String getStringFieldValue(int rowIndex, int fieldId) { |
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int recordOffset = (myHeader.getRecordLength() * rowIndex) +
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myHeader.getHeaderLength() + 1;
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//Se calcula el offset del campo
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int fieldOffset = 0; |
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for (int i = 0; i < fieldId; i++) { |
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fieldOffset += myHeader.getFieldLength(i); |
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} |
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buffer.position(recordOffset + fieldOffset); |
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byte[] data = new byte[myHeader.getFieldLength(fieldId)]; |
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buffer.get(data); |
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return new String(data); |
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} |
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// Retrieve the record at the given index
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/* public Object[] getRecord(long inIndex) throws IOException {
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long nRecordOffset = (myHeader.getRecordLength() * inIndex) +
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myHeader.getHeaderLength();
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// retrieve the record length
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int tempNumFields = myHeader.getNumFields();
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// storage for the actual values
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Object[] tempRow = new Object[tempNumFields];
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buffer.position((int) nRecordOffset);
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// read the deleted flag
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char tempDeleted = (char) buffer.get();
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// read the record length
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int tempRecordLength = 1; // for the deleted character just read.
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// read the Fields
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for (int j = 0; j < tempNumFields; j++) {
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// find the length of the field.
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int tempFieldLength = myHeader.getFieldLength(j);
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tempRecordLength = tempRecordLength + tempFieldLength;
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// find the field type
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char tempFieldType = myHeader.getFieldType(j);
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//System.out.print("Reading Name="+myHeader.getFieldName(j)+" Type="+tempFieldType +" Length="+tempFieldLength);
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// read the data.
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Object tempObject = null;
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switch (tempFieldType) {
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case 'L': // logical data type, one character (T,t,F,f,Y,y,N,n)
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char tempChar = (char) buffer.get();
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if ((tempChar == 'T') || (tempChar == 't') ||
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(tempChar == 'Y') || (tempChar == 'y')) {
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tempObject = new Boolean(true);
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} else {
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tempObject = new Boolean(false);
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}
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break;
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case 'C': // character record.
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byte[] sbuffer = new byte[tempFieldLength];
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buffer.get(sbuffer);
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tempObject = new String(sbuffer, "ISO-8859-1").trim();
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break;
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case 'D': // date data type.
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byte[] dbuffer = new byte[8];
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buffer.get(dbuffer);
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String tempString = new String(dbuffer, 0, 4);
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try {
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int tempYear = Integer.parseInt(tempString);
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tempString = new String(dbuffer, 4, 2);
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int tempMonth = Integer.parseInt(tempString) - 1;
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tempString = new String(dbuffer, 6, 2);
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int tempDay = Integer.parseInt(tempString);
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Calendar c = Calendar.getInstance();
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c.set(Calendar.YEAR, tempYear);
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c.set(Calendar.MONTH, tempMonth);
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c.set(Calendar.DAY_OF_MONTH, tempDay);
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tempObject = c.getTime();
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} catch (NumberFormatException e) {
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}
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break;
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case 'M': // memo field.
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byte[] mbuffer = new byte[10];
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buffer.get(mbuffer);
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break;
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case 'N': // number
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case 'F': // floating point number
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byte[] fbuffer = new byte[tempFieldLength];
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buffer.get(fbuffer);
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try {
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tempString = new String(fbuffer);
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tempObject = Double.valueOf(tempString.trim());
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} catch (NumberFormatException e) {
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}
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break;
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default:
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byte[] defbuffer = new byte[tempFieldLength];
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buffer.get(defbuffer);
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System.out.println("Do not know how to parse Field type " +
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tempFieldType);
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}
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tempRow[j] = tempObject;
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// System.out.println(" Data="+tempObject);
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}
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// ensure that the full record has been read.
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if (tempRecordLength < myHeader.getRecordLength()) {
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byte[] tempbuff = new byte[myHeader.getRecordLength() -
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tempRecordLength];
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buffer.get(tempbuff);
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/* if (tempTelling){
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System.out.println("DBF File has "+(myHeader.getRecordLength()-tempRecordLength)+" extra bytes per record");
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tempTelling = false;
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} */
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/* }
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return tempRow;
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}
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*/
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/**
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* Retrieve the name of the given column.
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*
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* @param inIndex DOCUMENT ME!
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*
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* @return DOCUMENT ME!
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*/
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public String getFieldName(int inIndex) { |
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return myHeader.getFieldName(inIndex).trim();
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} |
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/**
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* Retrieve the type of the given column.
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*
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* @param inIndex DOCUMENT ME!
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*
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* @return DOCUMENT ME!
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*/
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public char getFieldType(int inIndex) { |
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return myHeader.getFieldType(inIndex);
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} |
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/**
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* Retrieve the length of the given column.
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*
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* @param inIndex DOCUMENT ME!
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*
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* @return DOCUMENT ME!
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*/
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public int getFieldLength(int inIndex) { |
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return myHeader.getFieldLength(inIndex);
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} |
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/*
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* Retrieve the value of the given column as string.
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*
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* @param idField DOCUMENT ME!
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* @param idRecord DOCUMENT ME!
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*
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* @return DOCUMENT ME!
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*
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public Object getFieldValue(int idField, long idRecord) throws IOException {
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Object[] tmpReg = getRecord(idRecord);
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return tmpReg[idField];
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}
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*/
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/*
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* DOCUMENT ME!
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*
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* @param idField DOCUMENT ME!
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* @param idRecord DOCUMENT ME!
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*
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* @return DOCUMENT ME!
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*
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public double getFieldValueAsDouble(int idField, int idRecord) throws IOException {
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Object[] tmpReg = getRecord(idRecord);
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return (double) Double.parseDouble(tmpReg[idField].toString());
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}
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*/
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/**
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* Retrieve the location of the decimal point.
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*
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* @param inIndex DOCUMENT ME!
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*
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* @return DOCUMENT ME!
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*/
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public int getFieldDecimalLength(int inIndex) { |
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return myHeader.getFieldDecimalCount(inIndex);
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} |
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/**
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* read the DBF file into memory.
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*
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* @param file DOCUMENT ME!
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*
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* @throws IOException DOCUMENT ME!
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*/
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public void open(File file) throws IOException { |
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if (file.canWrite()){
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raf = new RandomAccessFile(file, "rw"); |
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mode = FileChannel.MapMode.READ_WRITE;
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} else {
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raf = new RandomAccessFile(file, "r"); |
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mode = FileChannel.MapMode.READ_ONLY;
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} |
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channel = raf.getChannel(); |
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// buffer = channel.map(FileChannel.MapMode.READ_ONLY, 0, channel.size());
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buffer = new BigByteBuffer(channel, mode);
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// create the header to contain the header information.
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myHeader = new DbaseFileHeader();
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myHeader.readHeader(buffer); |
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} |
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/**
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* Removes all data from the dataset
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*
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* @throws IOException DOCUMENT ME!
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*/
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public void close() throws IOException { |
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raf.close(); |
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channel.close(); |
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buffer = null;
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} |
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public FileChannel getWriteChannel() { |
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return channel;
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} |
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} |