Package org.geotools.gce.grassraster.core

Class GrassBinaryRasterReadHandler

Object
GrassBinaryRasterReadHandler
All Implemented Interfaces:
Closeable, AutoCloseable
public class GrassBinaryRasterReadHandler extends Object implements Closeable
Grass binary data input/ouput handler.

Reading and writing is supported.

Since:
3.0
Author:
Andrea Antonello (www.hydrologis.com)
See Also:

  • Constructor Details

    • GrassBinaryRasterReadHandler

      public GrassBinaryRasterReadHandler(File cellFile)
      the constructor to build a GrassBinaryRasterReadHandler usable for reading grass rasters.
      Parameters:
      cellFile - the file of the raw raster data.

  • Method Details

    • readRaster

      public WritableRaster readRaster(ImageReadParam param, boolean useSubSamplingAsRequestedRowcols, boolean castDoubleToFloating, ProgressListener monitor) throws IOException, DataFormatException
      Reads a grass raster, adding the possibility to override subsampling.
      Parameters:
      param - the read parameters.
      useSubSamplingAsRequestedRowcols - a flag that gives the possibility to bypass the imageio subsampling mechanism. With GRASS maps this is often more performing in some boundary situations. In the case this flag is set to true, the subsampling values will be handled as the requested columns and rows.
      castDoubleToFloating - a flag that gives the possibility to force the reading of a map as a floating point map. This is necessary right now because of a imageio bug: https://jai-imageio-core.dev.java.net /issues/show_bug.cgi?id=180
      Returns:
      the read raster
      Throws:
      IOException
      DataFormatException

    • readRaster

      public WritableRaster readRaster(ImageReadParam param) throws IOException, DataFormatException
      reads a grass raster, given the read parameters.

      The data are read into a single banded, floating point WritableRaster. A RectIter can be used to access the data afterwards.

      Parameters:
      param - the read parameters.
      Returns:
      the read raster
      Throws:
      IOException
      DataFormatException

    • parseHeaderAndAccessoryFiles

      public void parseHeaderAndAccessoryFiles() throws IOException
      Determines the metadata of the raster map.

      Reads the map type given a file and its mapset, the information from the header file in the cellhd directory and determines the geographic limits, format of the data, etc from the file. NOTE: for further informations about cell header files, read the package description.

      INFO: this is a reader method.

      Throws:
      IOException

    • getNativeRasterRegion

      public JGrassRegion getNativeRasterRegion()
      Getter for nativeRasterRegion.

      INFO: this is a reader method.

      Returns:
      the nativeRasterRegion.

    • getColorRules

      public List<String> getColorRules(double[] range) throws IOException
      Getter for the colorrules.

      INFO: this is a reader method.

      Returns:
      the list of single colorrules.
      Throws:
      IOException

    • getCategories

      public List<String> getCategories() throws IOException
      Getter for the categories.

      INFO: this is a reader method.

      Returns:
      the attribute table as read in the categories file
      Throws:
      IOException

    • close

      public void close() throws IOException
      closes the I/O streams.
      Specified by:
      close in interface AutoCloseable
      Specified by:
      close in interface Closeable
      Throws:
      IOException

    • abort

      public void abort()
      sets the abortrequired flag to true.

      As soon as possible that should abort the reader.

    • isAborting

      public boolean isAborting()
      Getter for the abortrequired flag.
      Returns:
      the abortRequired flag.

    • setNoData

      public void setNoData(double noData)
      Setter for the noData value.
      Parameters:
      noData - the nodata value to set.

    • getNoData

      public double getNoData()
      Getter for the noData value.
      Returns:
      the nodata value.

    • getCrs

      public CoordinateReferenceSystem getCrs() throws IOException
      Reads the crs definition for the map.

      The definition for grass maps is held in the location. Grass projection definitions are usually in a non parsable internal format. In JGrass we ask the user to choose the CRS. If the user doesn't do so, the CRS will result to be undefined.

      Returns:
      the CoordinateReferenceSystem for the map. Null if it is not defined.
      Throws:
      IOException - if there were problems in parsing the CRS file.

    • getSampleModel

      public SampleModel getSampleModel()
      returns the SampleModel compatible with the WritableRaster.
      Returns:
      the sample model compatible with the created raster

    • getRasterMapWidth

      public int getRasterMapWidth()

    • getRasterMapHeight

      public int getRasterMapHeight()

    • getRange

      public double[] getRange()