org.geotools.data.shapefile.dbf
Class IndexedDbaseFileReader

java.lang.Object
  org.geotools.data.shapefile.dbf.DbaseFileReader
      org.geotools.data.shapefile.dbf.IndexedDbaseFileReader

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 inherited from class org.geotools.data.shapefile.dbf.DbaseFileReader

DbaseFileReader.Row

Field Summary

Fields inherited from class org.geotools.data.shapefile.dbf.DbaseFileReader

currentOffset, randomAccessEnabled, useMemoryMappedBuffer

Constructor Summary

IndexedDbaseFileReader(java.nio.channels.ReadableByteChannel channel)
Like calling DbaseFileReader(ReadableByteChannel, true);

IndexedDbaseFileReader(java.nio.channels.ReadableByteChannel channel, boolean useMemoryMappedBuffer)
Creates a new instance of DBaseFileReader

Method Summary

void	goTo(int recno)
static void	main(java.lang.String[] args)

Methods inherited from class org.geotools.data.shapefile.dbf.DbaseFileReader

close, fill, getHeader, hasNext, readEntry, readEntry, readEntry, readRow, skip, transferTo

Methods inherited from class java.lang.Object

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

Constructor Detail

IndexedDbaseFileReader

public IndexedDbaseFileReader(java.nio.channels.ReadableByteChannel channel)
                       throws java.io.IOException

Like calling DbaseFileReader(ReadableByteChannel, true);

Parameters:

channel -

Throws:

java.io.IOException

IndexedDbaseFileReader

public IndexedDbaseFileReader(java.nio.channels.ReadableByteChannel channel,
                              boolean useMemoryMappedBuffer)
                       throws java.io.IOException

Creates a new instance of DBaseFileReader

Parameters:

channel - The readable channel to use.

useMemoryMappedBuffer - Wether or not map the file in memory

Throws:

java.io.IOException - If an error occurs while initializing.

Method Detail

goTo

public void goTo(int recno)
          throws java.io.IOException,
                 java.lang.UnsupportedOperationException

Parameters:

recno -

Throws:

java.io.IOException

java.lang.UnsupportedOperationException

main

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

Throws:

java.lang.Exception