svn-gvsig-desktop / trunk / libraries / libDataSourceBaseDrivers / src / org / gvsig / data / datastores / vectorial / file / dbf / utils / DbaseFileHeader.java @ 20414
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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 org.gvsig.data.datastores.vectorial.file.dbf.utils; |
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import java.io.IOException; |
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import java.nio.ByteBuffer; |
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import java.nio.ByteOrder; |
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import java.nio.channels.FileChannel; |
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import java.util.Calendar; |
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import java.util.Date; |
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import java.util.Iterator; |
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import org.gvsig.data.exception.UnsupportedTypeException; |
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import org.gvsig.data.exception.UnsupportedVersionException; |
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import org.gvsig.data.vectorial.IFeatureAttributeDescriptor; |
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import org.gvsig.data.vectorial.IFeatureType; |
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import com.iver.utiles.bigfile.BigByteBuffer2; |
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/**
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* Class to represent the header of a Dbase III file. Creation date: (5/15/2001
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* 5:15:30 PM)
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*/
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public class DbaseFileHeader { |
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// Constant for the size of a record
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private int FILE_DESCRIPTOR_SIZE = 32; |
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// type of the file, must be 03h
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private static final byte MAGIC = 0x03; |
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private static final int MINIMUM_HEADER = 33; |
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// type of the file, must be 03h
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private int myFileType = 0x03; |
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// Date the file was last updated.
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private Date myUpdateDate = new Date(); |
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// Number of records in the datafile
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private int myNumRecords = 0; |
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// Length of the header structure
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private int myHeaderLength; |
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// Length of the records
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private int myRecordLength; |
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// Number of fields in the record.
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private int myNumFields; |
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// collection of header records.
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private DbaseFieldDescriptor[] myFieldDescriptions; |
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private byte myLanguageID; |
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/**
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* DbaseFileHreader constructor comment.
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*/
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public DbaseFileHeader() {
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super();
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} |
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/**
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* Add a column to this DbaseFileHeader. The type is one of (C N L or D)
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* character, number, logical(true/false), or date. The Field length is
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* the total length in bytes reserved for this column. The decimal count
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* only applies to numbers(N), and floating point values (F), and refers
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* to the number of characters to reserve after the decimal point.
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*
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* @param inFieldName DOCUMENT ME!
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* @param inFieldType DOCUMENT ME!
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* @param inFieldLength DOCUMENT ME!
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* @param inDecimalCount DOCUMENT ME!
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* @throws BadFieldDriverException
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*
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* @throws Exception DOCUMENT ME!
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*/
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public void addColumn(String inFieldName, char inFieldType, |
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int inFieldLength, int inDecimalCount) throws UnsupportedTypeException { |
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if (inFieldLength <= 0) { |
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inFieldLength = 1;
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} |
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if (myFieldDescriptions == null) { |
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myFieldDescriptions = new DbaseFieldDescriptor[0]; |
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} |
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int tempLength = 1; // the length is used for the offset, and there is a * for deleted as the first byte |
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DbaseFieldDescriptor[] tempFieldDescriptors = new DbaseFieldDescriptor[myFieldDescriptions.length + |
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1];
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for (int i = 0; i < myFieldDescriptions.length; i++) { |
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myFieldDescriptions[i].myFieldDataAddress = tempLength; |
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tempLength = tempLength + myFieldDescriptions[i].myFieldLength; |
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tempFieldDescriptors[i] = myFieldDescriptions[i]; |
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} |
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tempFieldDescriptors[myFieldDescriptions.length] = new DbaseFieldDescriptor();
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tempFieldDescriptors[myFieldDescriptions.length].myFieldLength = inFieldLength; |
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tempFieldDescriptors[myFieldDescriptions.length].myDecimalCount = inDecimalCount; |
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tempFieldDescriptors[myFieldDescriptions.length].myFieldDataAddress = tempLength; |
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// set the field name
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String tempFieldName = inFieldName;
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if (tempFieldName == null) { |
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tempFieldName = "NoName";
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} |
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if (tempFieldName.length() > 11) { |
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tempFieldName = tempFieldName.substring(0, 11); |
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warn("FieldName " + inFieldName +
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" is longer than 11 characters, truncating to " +
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tempFieldName); |
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} |
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tempFieldDescriptors[myFieldDescriptions.length].myFieldName = tempFieldName; |
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// the field type
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if ((inFieldType == 'C') || (inFieldType == 'c')) { |
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tempFieldDescriptors[myFieldDescriptions.length].myFieldType = 'C';
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if (inFieldLength > 254) { |
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warn("Field Length for " + inFieldName + " set to " + |
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inFieldLength + |
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" Which is longer than 254, not consistent with dbase III");
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} |
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} else if ((inFieldType == 'S') || (inFieldType == 's')) { |
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tempFieldDescriptors[myFieldDescriptions.length].myFieldType = 'C';
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warn("Field type for " + inFieldName +
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" set to S which is flat out wrong people!, I am setting this to C, in the hopes you meant character.");
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if (inFieldLength > 254) { |
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warn("Field Length for " + inFieldName + " set to " + |
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inFieldLength + |
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" Which is longer than 254, not consistent with dbase III");
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} |
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tempFieldDescriptors[myFieldDescriptions.length].myFieldLength = 8;
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} else if ((inFieldType == 'D') || (inFieldType == 'd')) { |
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tempFieldDescriptors[myFieldDescriptions.length].myFieldType = 'D';
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if (inFieldLength != 8) { |
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warn("Field Length for " + inFieldName + " set to " + |
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inFieldLength + " Setting to 8 digets YYYYMMDD");
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} |
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tempFieldDescriptors[myFieldDescriptions.length].myFieldLength = 8;
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} else if ((inFieldType == 'F') || (inFieldType == 'f')) { |
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tempFieldDescriptors[myFieldDescriptions.length].myFieldType = 'F';
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if (inFieldLength > 20) { |
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warn("Field Length for " + inFieldName + " set to " + |
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inFieldLength + |
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" Preserving length, but should be set to Max of 20 not valid for dbase IV, and UP specification, not present in dbaseIII.");
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} |
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} else if ((inFieldType == 'N') || (inFieldType == 'n')) { |
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tempFieldDescriptors[myFieldDescriptions.length].myFieldType = 'N';
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if (inFieldLength > 18) { |
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warn("Field Length for " + inFieldName + " set to " + |
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inFieldLength + |
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" Preserving length, but should be set to Max of 18 for dbase III specification.");
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} |
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if (inDecimalCount < 0) { |
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warn("Field Decimal Position for " + inFieldName + " set to " + |
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inDecimalCount + |
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" Setting to 0 no decimal data will be saved.");
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tempFieldDescriptors[myFieldDescriptions.length].myDecimalCount = 0;
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} |
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if (inDecimalCount > (inFieldLength - 1)) { |
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warn("Field Decimal Position for " + inFieldName + " set to " + |
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inDecimalCount + " Setting to " + (inFieldLength - 1) + |
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" no non decimal data will be saved.");
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tempFieldDescriptors[myFieldDescriptions.length].myDecimalCount = inFieldLength - |
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1;
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} |
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} else if ((inFieldType == 'L') || (inFieldType == 'l')) { |
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tempFieldDescriptors[myFieldDescriptions.length].myFieldType = 'L';
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if (inFieldLength != 1) { |
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warn("Field Length for " + inFieldName + " set to " + |
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inFieldLength + |
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" Setting to length of 1 for logical fields.");
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} |
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tempFieldDescriptors[myFieldDescriptions.length].myFieldLength = 1;
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} else {
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throw new UnsupportedTypeException("DBF", ""+inFieldType, tempFieldName); |
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} |
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// the length of a record
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tempLength = tempLength + |
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tempFieldDescriptors[myFieldDescriptions.length].myFieldLength; |
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// set the new fields.
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myFieldDescriptions = tempFieldDescriptors; |
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myHeaderLength = 33 + (32 * myFieldDescriptions.length); |
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myNumFields = myFieldDescriptions.length; |
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myRecordLength = tempLength; |
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} |
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/**
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* Remove a column from this DbaseFileHeader.
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*
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* @param inFieldName DOCUMENT ME!
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*
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* @return index of the removed column, -1 if no found
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*/
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public int removeColumn(String inFieldName) { |
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int retCol = -1; |
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int tempLength = 1; |
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DbaseFieldDescriptor[] tempFieldDescriptors = new DbaseFieldDescriptor[myFieldDescriptions.length - |
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1];
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for (int i = 0, j = 0; i < myFieldDescriptions.length; i++) { |
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if (!inFieldName.equalsIgnoreCase(
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myFieldDescriptions[i].myFieldName.trim())) { |
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// if this is the last field and we still haven't found the
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// named field
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if ((i == j) && (i == (myFieldDescriptions.length - 1))) { |
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System.err.println("Could not find a field named '" + |
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inFieldName + "' for removal");
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return retCol;
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} |
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tempFieldDescriptors[j] = myFieldDescriptions[i]; |
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tempFieldDescriptors[j].myFieldDataAddress = tempLength; |
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tempLength += tempFieldDescriptors[j].myFieldLength; |
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// only increment j on non-matching fields
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j++; |
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} else {
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retCol = i; |
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} |
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} |
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// set the new fields.
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myFieldDescriptions = tempFieldDescriptors; |
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myHeaderLength = 33 + (32 * myFieldDescriptions.length); |
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myNumFields = myFieldDescriptions.length; |
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myRecordLength = tempLength; |
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return retCol;
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} |
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/**
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* DOCUMENT ME!
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*
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* @param inWarn DOCUMENT ME!
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*/
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private void warn(String inWarn) { |
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//TODO Descomentar esto cuando tenga la clase warning support
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// warnings.warn(inWarn);
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} |
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/**
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* Return the Field Descriptor for the given field.
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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 DbaseFieldDescriptor getFieldDescription(int inIndex) { |
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return myFieldDescriptions[inIndex];
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} |
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// Retrieve the length of the field at the given index
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public int getFieldLength(int inIndex) { |
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return myFieldDescriptions[inIndex].myFieldLength;
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} |
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// Retrieve the location of the decimal point within the field.
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public int getFieldDecimalCount(int inIndex) { |
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return myFieldDescriptions[inIndex].myDecimalCount;
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} |
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// Retrieve the Name of the field at the given index
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public String getFieldName(int inIndex) { |
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return myFieldDescriptions[inIndex].myFieldName;
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} |
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// Retrieve the type of field at the given index
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public char getFieldType(int inIndex) { |
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return myFieldDescriptions[inIndex].myFieldType;
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} |
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/**
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* Return the date this file was last updated.
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*
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* @return DOCUMENT ME!
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*/
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public Date getLastUpdateDate() { |
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return myUpdateDate;
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} |
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/**
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* Return the number of fields in the records.
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*
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* @return DOCUMENT ME!
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*/
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public int getNumFields() { |
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return myNumFields;
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} |
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/**
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* Return the number of records in the file
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*
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* @return DOCUMENT ME!
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*/
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public int getNumRecords() { |
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return myNumRecords;
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} |
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/**
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* Return the length of the records in bytes.
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*
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* @return DOCUMENT ME!
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*/
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public int getRecordLength() { |
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return myRecordLength;
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} |
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/**
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* Return the length of the header
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*
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* @return DOCUMENT ME!
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*/
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public int getHeaderLength() { |
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return myHeaderLength;
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} |
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/**
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* Read the header data from the DBF file.
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*
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* @param in DOCUMENT ME!
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* @throws UnsupportedVersionException
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*
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* @throws IOException DOCUMENT ME!
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*/
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public void readHeader(BigByteBuffer2 in) throws UnsupportedVersionException { |
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// type of file.
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myFileType = in.get(); |
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if (myFileType != 0x03) { |
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throw new UnsupportedVersionException("Unsupported DBF file Type " + |
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Integer.toHexString(myFileType),new Exception()); |
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} |
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// parse the update date information.
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int tempUpdateYear = (int) in.get(); |
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int tempUpdateMonth = (int) in.get(); |
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int tempUpdateDay = (int) in.get(); |
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tempUpdateYear = tempUpdateYear + 1900;
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Calendar c = Calendar.getInstance(); |
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c.set(Calendar.YEAR, tempUpdateYear);
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c.set(Calendar.MONTH, tempUpdateMonth - 1); |
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c.set(Calendar.DATE, tempUpdateDay);
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myUpdateDate = c.getTime(); |
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// read the number of records.
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in.order(ByteOrder.LITTLE_ENDIAN);
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myNumRecords = in.getInt(); |
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// read the length of the header structure.
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myHeaderLength = in.getShort(); |
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// read the length of a record
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myRecordLength = in.getShort(); //posicon 0h
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in.order(ByteOrder.BIG_ENDIAN);
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// skip the reserved bytes in the header.
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// in.position(in.position() + 20);
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// Leemos el byte de language
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in.position(29);
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myLanguageID = in.get(); |
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// Posicionamos para empezar a leer los campos.
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in.position(32);
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// calculate the number of Fields in the header
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myNumFields = (myHeaderLength - FILE_DESCRIPTOR_SIZE - 1) / FILE_DESCRIPTOR_SIZE;
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// read all of the header records
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myFieldDescriptions = new DbaseFieldDescriptor[myNumFields];
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int fieldOffset = 0; |
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for (int i = 0; i < myNumFields; i++) { |
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myFieldDescriptions[i] = new DbaseFieldDescriptor();
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// read the field name
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byte[] buffer = new byte[11]; |
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in.get(buffer); |
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myFieldDescriptions[i].myFieldName = new String(buffer); |
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// read the field type
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myFieldDescriptions[i].myFieldType = (char) in.get();
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// read the field data address, offset from the start of the record.
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myFieldDescriptions[i].myFieldDataAddress = in.getInt(); |
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// read the field length in bytes
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int tempLength = (int) in.get(); |
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if (tempLength < 0) { |
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tempLength = tempLength + 256;
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} |
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myFieldDescriptions[i].myFieldLength = tempLength; |
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// read the field decimal count in bytes
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myFieldDescriptions[i].myDecimalCount = (int) in.get();
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|
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// NUEVO: Calculamos los offsets aqu? para no
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// tener que recalcular cada vez que nos piden
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// algo.
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myFieldDescriptions[i].myFieldDataAddress = fieldOffset; |
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fieldOffset += tempLength; |
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// Fin NUEVO
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// read the reserved bytes.
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in.position(in.position() + 14);
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} |
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// Last byte is a marker for the end of the field definitions.
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in.get(); |
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} |
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/**
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* Set the number of records in the file
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*
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* @param inNumRecords DOCUMENT ME!
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*/
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public void setNumRecords(int inNumRecords) { |
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myNumRecords = inNumRecords; |
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} |
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|
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/*
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* Write the header data to the DBF file.
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*
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* @param out DOCUMENT ME!
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*
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* @throws Exception DOCUMENT ME!
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*
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public void writeHeader(LEDataOutputStream out) throws Exception {
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// write the output file type.
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out.writeByte(myFileType);
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// write the date stuff
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Calendar c = Calendar.getInstance();
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c.setTime(new Date());
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out.writeByte(c.get(Calendar.YEAR) - 1900);
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out.writeByte(c.get(Calendar.MONTH) + 1);
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out.writeByte(c.get(Calendar.DAY_OF_MONTH));
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// write the number of records in the datafile.
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out.writeInt(myNumRecords);
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// write the length of the header structure.
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out.writeShort(myHeaderLength);
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// write the length of a record
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out.writeShort(myRecordLength);
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// write the reserved bytes in the header
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for (int i = 0; i < 20; i++)
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out.writeByte(0);
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// write all of the header records
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int tempOffset = 0;
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for (int i = 0; i < myFieldDescriptions.length; i++) {
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// write the field name
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for (int j = 0; j < 11; j++) {
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if (myFieldDescriptions[i].myFieldName.length() > j) {
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out.writeByte((int) myFieldDescriptions[i].myFieldName.charAt(
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j));
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} else {
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out.writeByte(0);
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}
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}
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// write the field type
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out.writeByte(myFieldDescriptions[i].myFieldType);
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// write the field data address, offset from the start of the record.
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out.writeInt(tempOffset);
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tempOffset += myFieldDescriptions[i].myFieldLength;
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// write the length of the field.
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out.writeByte(myFieldDescriptions[i].myFieldLength);
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// write the decimal count.
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out.writeByte(myFieldDescriptions[i].myDecimalCount);
|
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// write the reserved bytes.
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for (int j = 0; j < 14; j++)
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out.writeByte(0);
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}
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// write the end of the field definitions marker
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out.writeByte(0x0D);
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}
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*/
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|
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/**
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* Class for holding the information assicated with a record.
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*/
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class DbaseFieldDescriptor { |
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// Field Name
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String myFieldName;
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|
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// Field Type (C N L D F or M)
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char myFieldType;
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|
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// Field Data Address offset from the start of the record.
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int myFieldDataAddress;
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|
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// Length of the data in bytes
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int myFieldLength;
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|
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// Field decimal count in Binary, indicating where the decimal is
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int myDecimalCount;
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} |
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|
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public byte getLanguageID() { |
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return myLanguageID;
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} |
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|
527 |
public static DbaseFileHeader createDbaseHeader(IFeatureType featureType) throws UnsupportedTypeException { |
528 |
DbaseFileHeader header = new DbaseFileHeader();
|
529 |
Iterator iterator=featureType.iterator();
|
530 |
while (iterator.hasNext()) {
|
531 |
IFeatureAttributeDescriptor descriptor = (IFeatureAttributeDescriptor) iterator.next(); |
532 |
|
533 |
|
534 |
String type = descriptor.getDataType();
|
535 |
String colName = descriptor.getName();
|
536 |
|
537 |
int fieldLen = descriptor.getSize(); // TODO aqu? el |
538 |
// tama?o no es
|
539 |
// correcto hay que
|
540 |
// calcularlo, ahora
|
541 |
// mismo est? puesto
|
542 |
// a pi??n.
|
543 |
int decimales = descriptor.getPrecision();
|
544 |
|
545 |
if (IFeatureAttributeDescriptor.TYPE_DOUBLE == type ||
|
546 |
IFeatureAttributeDescriptor.TYPE_FLOAT == type || |
547 |
IFeatureAttributeDescriptor.TYPE_INT == type || |
548 |
IFeatureAttributeDescriptor.TYPE_LONG == type ){ |
549 |
header.addColumn(colName, 'N', Math.min(fieldLen, 18), |
550 |
decimales); |
551 |
}else if (IFeatureAttributeDescriptor.TYPE_DATE == type ){ |
552 |
header.addColumn(colName, 'D', fieldLen, 0); |
553 |
}else if (IFeatureAttributeDescriptor.TYPE_BOOLEAN == type ){ |
554 |
header.addColumn(colName, 'L', 1, 0); |
555 |
}else if (IFeatureAttributeDescriptor.TYPE_STRING == type ){ |
556 |
header.addColumn(colName, 'C', Math.min(254, fieldLen), 0); |
557 |
} |
558 |
|
559 |
|
560 |
} |
561 |
return header;
|
562 |
} |
563 |
/**
|
564 |
* Write the header data to the DBF file.
|
565 |
*
|
566 |
* @param out
|
567 |
* A channel to write to. If you have an OutputStream you can
|
568 |
* obtain the correct channel by using
|
569 |
* java.nio.Channels.newChannel(OutputStream out).
|
570 |
*
|
571 |
* @throws IOException
|
572 |
* If errors occur.
|
573 |
*/
|
574 |
public void writeHeader(FileChannel out) throws IOException { |
575 |
// take care of the annoying case where no records have been added...
|
576 |
if (myHeaderLength == -1) { |
577 |
myHeaderLength = MINIMUM_HEADER; |
578 |
} |
579 |
|
580 |
// Desde el principio
|
581 |
out.position(0);
|
582 |
|
583 |
ByteBuffer buffer = ByteBuffer.allocateDirect(myHeaderLength); |
584 |
buffer.order(ByteOrder.LITTLE_ENDIAN);
|
585 |
|
586 |
// write the output file type.
|
587 |
buffer.put((byte) MAGIC);
|
588 |
|
589 |
// write the date stuff
|
590 |
Calendar c = Calendar.getInstance(); |
591 |
c.setTime(new Date()); |
592 |
buffer.put((byte) (c.get(Calendar.YEAR) % 100)); |
593 |
buffer.put((byte) (c.get(Calendar.MONTH) + 1)); |
594 |
buffer.put((byte) (c.get(Calendar.DAY_OF_MONTH))); |
595 |
|
596 |
// write the number of records in the datafile.
|
597 |
buffer.putInt(myNumRecords); |
598 |
|
599 |
// write the length of the header structure.
|
600 |
buffer.putShort((short) myHeaderLength);
|
601 |
|
602 |
// write the length of a record
|
603 |
buffer.putShort((short) myRecordLength);
|
604 |
|
605 |
// // write the reserved bytes in the header
|
606 |
// for (int i=0; i<20; i++) out.writeByteLE(0);
|
607 |
buffer.position(buffer.position() + 20);
|
608 |
|
609 |
// write all of the header records
|
610 |
int tempOffset = 0; |
611 |
|
612 |
if (myFieldDescriptions != null) { |
613 |
for (int i = 0; i < myFieldDescriptions.length; i++) { |
614 |
// write the field name
|
615 |
for (int j = 0; j < 11; j++) { |
616 |
if (myFieldDescriptions[i].myFieldName.length() > j) {
|
617 |
buffer.put((byte) myFieldDescriptions[i].myFieldName.charAt(j));
|
618 |
} else {
|
619 |
buffer.put((byte) 0); |
620 |
} |
621 |
} |
622 |
|
623 |
// write the field type
|
624 |
buffer.put((byte) myFieldDescriptions[i].myFieldType);
|
625 |
|
626 |
// // write the field data address, offset from the start of the
|
627 |
// record.
|
628 |
buffer.putInt(tempOffset); |
629 |
tempOffset += myFieldDescriptions[i].myFieldLength; |
630 |
|
631 |
// write the length of the field.
|
632 |
buffer.put((byte) myFieldDescriptions[i].myFieldLength);
|
633 |
|
634 |
// write the decimal count.
|
635 |
buffer.put((byte) myFieldDescriptions[i].myDecimalCount);
|
636 |
|
637 |
// write the reserved bytes.
|
638 |
// for (in j=0; jj<14; j++) out.writeByteLE(0);
|
639 |
buffer.position(buffer.position() + 14);
|
640 |
} |
641 |
} |
642 |
// write the end of the field definitions marker
|
643 |
buffer.put((byte) 0x0D); |
644 |
|
645 |
buffer.position(0);
|
646 |
|
647 |
int r = buffer.remaining();
|
648 |
|
649 |
while ((r -= out.write(buffer)) > 0) { |
650 |
; // do nothing
|
651 |
} |
652 |
} |
653 |
|
654 |
} |