plot images for the flip book

RSample.java

package rJava;

import java.awt.Color;
import java.awt.Graphics;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;

import javax.imageio.ImageIO;
import javax.swing.JFrame;
import javax.swing.JPanel;

import org.rosuda.JRI.REXP;
import org.rosuda.JRI.Rengine;

public class RSample extends JPanel implements KeyListener, Runnable {
	private final String[] _exprs = {
			"a*x+b", "a*x^b", "a*b^x"
	};
	private final String[] _ltys = {
			"dotted", "dashed", "solid"
	};
	private final int _INDEX_INIT = 7;
	private final String _plotArgs = "xlim= xlim, ylim= ylim"
			+ ", xlab= 'Xの値', ylab= 'Yの値', family= 'Osaka-Mono'";

	private Rengine _engine;
	private boolean _loopFlag = true;
	private boolean _lockFlag = false;
	private Thread _thread;
	private File _file;

	private int _index = 7;
	private int _n = 0;

	public RSample() {
		setSize(480, 480);
		setFocusable(true); // KeyListnerに必要な設定
		addKeyListener(this);

		_engine = new Rengine(new String[] {
			"--no-save"
		}, false, null);
		init();
		_file = paintIMP();
	}

	@Override
	public void paintComponent(Graphics g) {
		super.paintComponent(g);
		g.setColor(Color.RED);
		g.fillRect(0, 0, getWidth(), getHeight());
		if (_file != null) {
			try {
				BufferedImage img = ImageIO.read(_file);
				g.drawImage(img, 0, 0, this);
			} catch (Exception e) {
				e.printStackTrace();
				_file.delete();
				_file = null;
			}
		}
		_lockFlag = false;
	}

	private void init() {
		String filename = "dist.dat";
		_engine.eval("data<-read.csv(\"" + filename + "\")");
		_engine.eval("d1<-data[,1]");
		_engine.eval("d2<-data[,2]");
		_engine.eval("n<-length(d1)");
		_engine.eval("xlim<-c(0,n-1)");
		_engine.eval("ylim<-c(0,30)");
		_engine.eval("r<-sample(c(0:n-1), n)");
		_n = _engine.eval("n").asInt();
	}

	private File paintIMP() {
		File file = null;
		try {
			file = File.createTempFile("plot", ".png");
		} catch (IOException e) {
			return null;
		}
		file.deleteOnExit();
		_engine.eval("rv<-sort(r[0:" + _index + "])");
		_engine.eval("x<-d1[rv]");
		_engine.eval("y<-d2[rv]");
		_engine.eval("png('" + file.getAbsolutePath() + "')");
		_engine.eval("plot(x, y, " + _plotArgs + ")");
		_engine.eval("grid()");

		String exprary = String.format("'sample(n=%d)'", _index);
		String ltyary = "'blank'";
		String pchary = "1";
		for (int i = 0; i < _exprs.length; i++) {
			if (curve_fitting(_exprs[i], _ltys[i])) {
				exprary += ", expression(" + _exprs[i] + ")";
				ltyary += ", '" + _ltys[i] + "'";
				pchary += ", -1";
			}
		}

		String legend = "legend('topright'";
		legend += ", c(" + exprary + ")";
		legend += ", lty=c(" + ltyary + ")";
		legend += ", pch=c(" + pchary + ")";
		legend += ")";
		_engine.eval(legend);

		_engine.eval("dev.off()");
		return file;
	}

	private boolean curve_fitting(String f, String c) {
		REXP r = _engine.eval("result<-nls(y~(" + f + "), start=c(a=1, b=1))");
		if (r == null)
			return false;
		_engine.eval("p<-result$m$getPars()");
		_engine.eval("a= p[1]");
		_engine.eval("b= p[2]");
		_engine.eval("func= function(x) " + f);
		_engine.eval("plot(func, 0, n, add=TRUE, lty='" + c + "')");
		return true;
	}

	private void start() {
		_thread = new Thread(this);
		_loopFlag = true;
		_index = _INDEX_INIT;
		_thread.start();
	}

	@Override
	public void run() {
		try {
			System.out.println("start");
			while (_loopFlag) {
				_lockFlag = true;
				repaint();
				do {
					Thread.sleep(10);
				} while (_lockFlag);
				_file = paintIMP();
				_index++;
				if (_index >= _n || _index >= 400) {
					_loopFlag = false;
				}
			}
			System.out.println("end");
		} catch (Exception e) {
			e.printStackTrace();
			_engine.end();
		}
	}

	public static void main(String[] args) {
		System.out.println("R_HOME:" + System.getenv("R_HOME"));
		System.out.println("java.library.path:"
				+ System.getProperty("java.library.path"));

		JFrame f = new JFrame();
		RSample p = new RSample();
		f.getRootPane().add(p);
		f.setSize(480, 500);
		f.addWindowListener(new WindowAdapter() {
			public void windowClosing(WindowEvent e) {
				if (p._engine != null && p._engine.isAlive())
					p._engine.end();
				if (p._thread != null && p._thread.isAlive())
					p._loopFlag = false;
				System.exit(0);
			}
		});
		f.setVisible(true);
		p.repaint(10);
	}

	@Override
	public void keyTyped(KeyEvent e) {
	}

	@Override
	public void keyPressed(KeyEvent e) {
	}

	@Override
	public void keyReleased(KeyEvent e) {
		if (e.getKeyCode() == 32) {
			if (!(_thread != null && _thread.isAlive()))
				this.start();
		}
	}
}