Package org.geotools.data.shapefile.dbf

Class IndexedDbaseFileReader

Object

DbaseFileReader

IndexedDbaseFileReader

All Implemented Interfaces:

Closeable, AutoCloseable, FileReader

public class IndexedDbaseFileReader
extends DbaseFileReader

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

 FileChannel in = new FileInputStream("thefile.dbf").getChannel();
 DbaseFileReader r = new DbaseFileReader( in )
 Object[] fields = new Object[r.getHeader().getNumFields()];
 while (r.hasNext()) {
    r.readEntry(fields);
    // do stuff
 }
 r.close();
 

For consumers who wish to be a bit more selective with their reading of rows, the Row object has been added. The semantics are the same as using the readEntry method, but remember that the Row object is always the same. The values are parsed as they are read, so it pays to copy them out (as each call to Row.read() will result in an expensive String parse).
EACH CALL TO readEntry OR readRow ADVANCES THE FILE!
An example of using the Row method of reading:

 FileChannel in = new FileInputStream("thefile.dbf").getChannel();
 DbaseFileReader r = new DbaseFileReader( in )
 int fields = r.getHeader().getNumFields();
 while (r.hasNext()) {
   DbaseFileReader.Row row = r.readRow();
   for (int i = 0; i < fields; i++) {
     // do stuff
     Foo.bar( row.read(i) );
   }
 }
 r.close();
 

Author:

Ian Schneider, Tommaso Nolli

Nested Class Summary

Nested classes/interfaces inherited from class DbaseFileReader

DbaseFileReader.Row

Field Summary

Fields inherited from class DbaseFileReader

currentOffset, randomAccessEnabled, useMemoryMappedBuffer

Constructor Summary

Constructors

Constructor	Description
IndexedDbaseFileReader(ShpFiles shpFiles)	Like calling DbaseFileReader(ReadableByteChannel, true);
IndexedDbaseFileReader(ShpFiles shpFiles, boolean useMemoryMappedBuffer)	Creates a new instance of DBaseFileReader
IndexedDbaseFileReader(ShpFiles shpFiles, boolean useMemoryMappedBuffer, Charset stringCharset)
IndexedDbaseFileReader(ShpFiles shpFiles, boolean useMemoryMappedBuffer, Charset stringCharset, TimeZone timeZone)

Method Summary

Modifier and Type	Method	Description
void	goTo(int recno)
boolean	IsRandomAccessEnabled()
static void	main(String[] args)

Methods inherited from class DbaseFileReader

close, fill, getHeader, hasNext, id, read, readEntry, readEntry, readEntry, readField, readRow, skip, transferTo

Methods inherited from class Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

IndexedDbaseFileReader

public IndexedDbaseFileReader(ShpFiles shpFiles)
                       throws IOException

Like calling DbaseFileReader(ReadableByteChannel, true);

Throws:

IOException

IndexedDbaseFileReader

public IndexedDbaseFileReader(ShpFiles shpFiles,
                              boolean useMemoryMappedBuffer)
                       throws IOException

Creates a new instance of DBaseFileReader

Parameters:

useMemoryMappedBuffer - Wether or not map the file in memory

Throws:

IOException - If an error occurs while initializing.

IndexedDbaseFileReader

public IndexedDbaseFileReader(ShpFiles shpFiles,
                              boolean useMemoryMappedBuffer,
                              Charset stringCharset)
                       throws IOException

Throws:

IOException

IndexedDbaseFileReader

public IndexedDbaseFileReader(ShpFiles shpFiles,
                              boolean useMemoryMappedBuffer,
                              Charset stringCharset,
                              TimeZone timeZone)
                       throws IOException

Throws:

IOException

Method Detail

goTo

public void goTo(int recno)
          throws IOException,
                 UnsupportedOperationException

Throws:

IOException

UnsupportedOperationException

IsRandomAccessEnabled

public boolean IsRandomAccessEnabled()

main

public static void main(String[] args)
                 throws Exception

Throws:

Exception