us.zuercher.gpx2map.source
Class AbstractTiledUrlMapSource

java.lang.Object
  us.zuercher.gpx2map.source.AbstractCachedMapSource
      us.zuercher.gpx2map.source.AbstractTiledUrlMapSource

All Implemented Interfaces:

MapSource

Direct Known Subclasses:

DummyMapSource, TerraserverUsaMapSource

public abstract class AbstractTiledUrlMapSource
extends AbstractCachedMapSource
implements MapSource

AbstractTilesUrlMapSource extends AbstractCachedMapSource to provide a MapSource base class that provides map tile downloading and stitching facilities.

For the purposes of stitchTiles(File, ProgressMeter), map tiles are assumed to be gzipped PPM files. Individual tiles file names are retrieve from the cache via the abstract method getTile(int, int). The column and row information passed in that method are derived from the return values of the abstract methods getColumnCount() and getRowCount().

Author:

Stephan Zuercher

Constructor Summary

AbstractTiledUrlMapSource()

Method Summary

protected void	download(URL url, File target) Downloads, converts and compresses an image from the given source URL to the given target file.
protected void	download(URL url, File target, boolean convertAndCompress) Downloads, converts and compresses an image from the given source URL to the given target file.
protected abstract int	getColumnCount() Returns the number of tile columns for the current map.
protected String	getCompressedCacheFileExtension() Returns the extension that should be used for downloaded files.
protected abstract int	getRowCount() Returns the number of tile rows for the current map.
protected abstract File	getTile(int column, int row) Returns the File object for the tile at the given coordinates.
void	stitchTiles(File outputFile, ProgressMeter meter) Stitches together tiles files obtained from the concrete base class.

Methods inherited from class us.zuercher.gpx2map.source.AbstractCachedMapSource

getCacheDir, setCacheDir

Methods inherited from class java.lang.Object

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

Methods inherited from interface us.zuercher.gpx2map.source.MapSource

downloadTiles, getImageSize, getMapScale, getProperties, mapLocationToPixel, setBoundingBox, setCacheDir, setProperty

Constructor Detail

AbstractTiledUrlMapSource

public AbstractTiledUrlMapSource()

Method Detail

stitchTiles

public void stitchTiles(File outputFile,
                        ProgressMeter meter)
                 throws IOException

Stitches together tiles files obtained from the concrete base class. Tiles files are obtained from getTile(int, int), getColumnCount(), and getRowCount().

Specified by:

stitchTiles in interface MapSource

Parameters:

outputFile - the output file, a gzipped PPM file

meter - a progress meter

Throws:

IOException - if there's an error reading the input files, or writing to the output file.

See Also:

MapSource.stitchTiles(File, ProgressMeter)

getColumnCount

protected abstract int getColumnCount()

Returns the number of tile columns for the current map.

Returns:

number of tile columns.

getRowCount

protected abstract int getRowCount()

Returns the number of tile rows for the current map.

Returns:

number of tile rows.

getTile

protected abstract File getTile(int column,
                                int row)

Returns the File object for the tile at the given coordinates.

Parameters:

column - 0-based column index

row - 0-based row index

Returns:

File for the given tile.

download

protected void download(URL url,
                        File target,
                        boolean convertAndCompress)
                 throws IOException

Downloads, converts and compresses an image from the given source URL to the given target file.

Parameters:

url - image source URL

target - image target file.

convertAndCompress - if true, attempts to convert the file to PPM format and apply gzip compression.

Throws:

IOException - if there's an error downloading the file

See Also:

MapSource.downloadTiles(ProgressMeter), JavaDownloader, JavaConverter

download

protected void download(URL url,
                        File target)
                 throws IOException

Downloads, converts and compresses an image from the given source URL to the given target file. Equivalent to calling download(url, target, true).

Parameters:

url - image source URL

target - image target file.

Throws:

IOException - if there's an error downloading the file

See Also:

MapSource.downloadTiles(ProgressMeter), JavaDownloader, JavaConverter

getCompressedCacheFileExtension

protected String getCompressedCacheFileExtension()

Returns the extension that should be used for downloaded files.

Returns:

the extension that should be used for downloaded files.

See Also:

JavaConverter