math/R・rJavaでのPlot画像をJavaのPanelに貼り付ける

rJavaを用いてJavaからRを動かしたPostのRSampleと入れ替えてみる．
（ファイルにPNG画像を書き出して読み込んで描画するを繰り返すので注意）

	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();
	}
	}
	}

view raw RSample.java hosted with ❤ by GitHub

結果