/*
* Copyright (C) 2011-2012 Dr. John Lindsay <jlindsay@uoguelph.ca>
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
package plugins;
import java.util.Date;
import java.util.Iterator;
import java.util.PriorityQueue;
import java.util.Random;
import whitebox.geospatialfiles.WhiteboxRaster;
import whitebox.interfaces.WhiteboxPlugin;
import whitebox.interfaces.WhiteboxPluginHost;
/**
* This tool can be used to create a random sample of grid cells.
*
* @author Dr. John Lindsay email: jlindsay@uoguelph.ca
*/
public class RandomSample implements WhiteboxPlugin {
private WhiteboxPluginHost myHost = null;
private String[] args;
/**
* Used to retrieve the plugin tool's name. This is a short, unique name
* containing no spaces.
*
* @return String containing plugin name.
*/
@Override
public String getName() {
return "RandomSample";
}
/**
* Used to retrieve the plugin tool's descriptive name. This can be a longer
* name (containing spaces) and is used in the interface to list the tool.
*
* @return String containing the plugin descriptive name.
*/
@Override
public String getDescriptiveName() {
return "Random Sample";
}
/**
* Used to retrieve a short description of what the plugin tool does.
*
* @return String containing the plugin's description.
*/
@Override
public String getToolDescription() {
return "Creates an image containing randomly located sample grid cells.";
}
/**
* Used to identify which toolboxes this plugin tool should be listed in.
*
* @return Array of Strings.
*/
@Override
public String[] getToolbox() {
String[] ret = { "StatisticalTools" };
return ret;
}
/**
* Sets the WhiteboxPluginHost to which the plugin tool is tied. This is the
* class that the plugin will send all feedback messages, progress updates,
* and return objects.
*
* @param host The WhiteboxPluginHost that called the plugin tool.
*/
@Override
public void setPluginHost(WhiteboxPluginHost host) {
myHost = host;
}
/**
* Used to communicate feedback pop-up messages between a plugin tool and
* the main Whitebox user-interface.
*
* @param feedback String containing the text to display.
*/
private void showFeedback(String message) {
if (myHost != null) {
myHost.showFeedback(message);
} else {
System.out.println(message);
}
}
/**
* Used to communicate a return object from a plugin tool to the main
* Whitebox user-interface.
*
* @return Object, such as an output WhiteboxRaster.
*/
private void returnData(Object ret) {
if (myHost != null) {
myHost.returnData(ret);
}
}
private int previousProgress = 0;
private String previousProgressLabel = "";
/**
* Used to communicate a progress update between a plugin tool and the main
* Whitebox user interface.
*
* @param progressLabel A String to use for the progress label.
* @param progress Float containing the progress value (between 0 and 100).
*/
private void updateProgress(String progressLabel, int progress) {
if (myHost != null && ((progress != previousProgress) ||
(!progressLabel.equals(previousProgressLabel)))) {
myHost.updateProgress(progressLabel, progress);
}
previousProgress = progress;
previousProgressLabel = progressLabel;
}
/**
* Used to communicate a progress update between a plugin tool and the main
* Whitebox user interface.
*
* @param progress Float containing the progress value (between 0 and 100).
*/
private void updateProgress(int progress) {
if (myHost != null && progress != previousProgress) {
myHost.updateProgress(progress);
}
previousProgress = progress;
}
/**
* Sets the arguments (parameters) used by the plugin.
*
* @param args An array of string arguments.
*/
@Override
public void setArgs(String[] args) {
this.args = args.clone();
}
private boolean cancelOp = false;
/**
* Used to communicate a cancel operation from the Whitebox GUI.
*
* @param cancel Set to true if the plugin should be canceled.
*/
@Override
public void setCancelOp(boolean cancel) {
cancelOp = cancel;
}
private void cancelOperation() {
showFeedback("Operation cancelled.");
updateProgress("Progress: ", 0);
}
private boolean amIActive = false;
/**
* Used by the Whitebox GUI to tell if this plugin is still running.
*
* @return a boolean describing whether or not the plugin is actively being
* used.
*/
@Override
public boolean isActive() {
return amIActive;
}
/**
* Used to execute this plugin tool.
*/
@Override
public void run() {
amIActive = true;
String inputHeader = null;
String outputHeader = null;
WhiteboxRaster image;
WhiteboxRaster output;
int cols, rows;
int progress = 0;
int col, row;
int i;
int numSamplePoints = 0;
if (args.length <= 0) {
showFeedback("Plugin parameters have not been set.");
return;
}
inputHeader = args[0];
outputHeader = args[1];
numSamplePoints = Integer.parseInt(args[2]);
// check to see that the inputHeader and outputHeader are not null.
if ((inputHeader == null) || (outputHeader == null)) {
showFeedback("One or more of the input parameters have not been set properly.");
return;
}
try {
image = new WhiteboxRaster(inputHeader, "r");
rows = image.getNumberRows();
cols = image.getNumberColumns();
if (rows * cols < numSamplePoints) {
showFeedback("The number of samples cannot exceed the number of cells.");
return;
}
output = new WhiteboxRaster(outputHeader, "rw", inputHeader, WhiteboxRaster.DataType.FLOAT, 0);
output.setPreferredPalette("qual.pal");
output.setDataScale(WhiteboxRaster.DataScale.CATEGORICAL);
image.close();
// A priority gueue is used so that we can later add each of the
// points to the grid sorted by row value. Otherwise we will end up
// reading and writing to disc a lot as we enter values to the grid
// in random locations.
NonDuplicatingPriorityQueue queue = new NonDuplicatingPriorityQueue(numSamplePoints);
Random generator = new Random();
GridCell gc;
i = 0;
do {
row = generator.nextInt(rows);
col = generator.nextInt(cols);
gc = new GridCell(row, col);
if (queue.add(gc)) {
i++;
progress = (int)(100f * i / numSamplePoints);
updateProgress("Loop 1 of 2:", progress);
}
} while (i < numSamplePoints);
Iterator<GridCell> it = queue.iterator();
i = 1;
do {
// Returns an iterator over the elements in this queue.
gc = queue.poll();
output.setValue(gc.row, gc.col, i);
i++;
progress = (int)(100f * i / numSamplePoints);
updateProgress("Loop 2 of 2:", progress);
} while (i < numSamplePoints);
output.addMetadataEntry("Created by the "
+ getDescriptiveName() + " tool.");
output.addMetadataEntry("Created on " + new Date());
output.close();
// returning a header file string displays the image.
returnData(outputHeader);
} catch (OutOfMemoryError oe) {
myHost.showFeedback("An out-of-memory error has occurred during operation.");
} catch (Exception e) {
myHost.showFeedback("An error has occurred during operation. See log file for details.");
myHost.logException("Error in " + getDescriptiveName(), e);
} finally {
updateProgress("Progress: ", 0);
// tells the main application that this process is completed.
amIActive = false;
myHost.pluginComplete();
}
}
class NonDuplicatingPriorityQueue extends PriorityQueue<GridCell> {
public NonDuplicatingPriorityQueue(int initialCapacity) {
super(initialCapacity);
}
@Override
public boolean add(GridCell gc) {
try {
// This will only add the gridcell if it's not already in the queue.
Iterator<GridCell> i = this.iterator();
while (i.hasNext()) {
// Returns an iterator over the elements in this queue.
GridCell gc2 = i.next();
if (gc.compareTo(gc2) == 0) {
return false;
}
}
super.add(gc);
return true;
} catch (Exception e) {
return false;
}
}
}
class GridCell implements Comparable<GridCell> {
public int row;
public int col;
public GridCell(int row, int col) {
this.row = row;
this.col = col;
}
@Override
public int compareTo(GridCell cell) {
final int BEFORE = -1;
final int EQUAL = 0;
final int AFTER = 1;
if (this.row < cell.row) {
return BEFORE;
} else if (this.row > cell.row) {
return AFTER;
}
if (this.col < cell.col) {
return BEFORE;
} else if (this.col > cell.col) {
return AFTER;
}
return EQUAL;
}
}
// // This method is only used during testing.
// public static void main(String[] args) {
// args = new String[3];
// args[0] = "/Users/johnlindsay/Documents/Data/Waterloo streams.dep";
// args[1] = "/Users/johnlindsay/Documents/Data/tmp2.dep";
// args[2] = "1000";
//
// RandomSample rs = new RandomSample();
// rs.setArgs(args);
// rs.run();
// }
}