Significant update for WEB interface in particular.

Now we show the directory page with JPEG images in them.

src/org/forkalsrud/album/web/AlbumServlet.java

@@ -0,0 +1,160 @@
+package org.forkalsrud.album.web;
+
+import java.awt.Graphics2D;
+import java.awt.geom.AffineTransform;
+import java.awt.image.BufferedImage;
+import java.io.*;
+import java.text.ParseException;
+import java.util.*;
+
+import javax.imageio.ImageIO;
+import javax.imageio.ImageReadParam;
+import javax.imageio.ImageReader;
+import javax.imageio.ImageWriteParam;
+import javax.imageio.ImageWriter;
+import javax.imageio.stream.ImageInputStream;
+import javax.imageio.stream.ImageOutputStream;
+import javax.servlet.*;
+import javax.servlet.http.*;
+
+import org.forkalsrud.album.exif.Dimension;
+import org.forkalsrud.album.exif.Entry;
+import org.forkalsrud.album.exif.EntryDao;
+
+import com.drew.imaging.jpeg.JpegProcessingException;
+import com.drew.metadata.MetadataException;
+
+public class AlbumServlet
+    extends HttpServlet
+{
+    EntryDao dao;
+
+    @Override
+    public void init()
+        throws ServletException
+    {
+        System.out.println("in init of Album");
+        dao = new EntryDao();
+    }
+
+    @Override
+    public void doGet(HttpServletRequest req, HttpServletResponse res)
+        throws ServletException, IOException
+    {
+        System.out.println("pathInfo: " + req.getPathInfo());
+        System.out.println("pathXlat: " + req.getPathTranslated());
+        System.out.println("queryString: " + req.getQueryString());
+        System.out.println("requestUri: " + req.getRequestURI());
+        System.out.println("servletPath: " + req.getServletPath());
+
+        String path = req.getPathTranslated();
+
+        System.out.println("file: " + path);
+
+        File file = new File(path);
+        if (file == null) {
+            res.setStatus(HttpServletResponse.SC_NOT_FOUND);
+            return;
+        }
+
+        if (!file.exists()) {
+            res.setStatus(HttpServletResponse.SC_NOT_FOUND);
+            return;
+        }
+
+        if (!file.canRead()) {
+            res.setStatus(HttpServletResponse.SC_FORBIDDEN);
+            return;
+        }
+
+        if (file.isDirectory()) {
+            try {
+                List<Entry> entries = dao.read(file);
+                res.setContentType("text/html");
+                req.setAttribute("directory", file.getName());
+                req.setAttribute("path", req.getServletPath());
+                req.setAttribute("entries", entries);
+                RequestDispatcher rd = req.getRequestDispatcher("/WEB-INF/velocity/directory.vm");
+                rd.forward(req, res);
+
+            } catch (Exception e) {
+                throw new ServletException("sadness", e);
+            }
+        } else if (req.getParameter("size") != null) {
+
+            try {
+                res.setContentType("image/jpeg");
+                scaleImage(req, res, file, Integer.parseInt(req.getParameter("size")));
+            } catch (Exception e) {
+                throw new RuntimeException("sadness", e);
+            }
+        } else {
+            res.setStatus(HttpServletResponse.SC_NOT_FOUND);
+        }            
+    }
+
+
+    void scaleImage(HttpServletRequest req, HttpServletResponse res, File file, int size) throws IOException, JpegProcessingException, MetadataException, ParseException {
+
+        List<Entry> entries = dao.read(file.getParentFile());
+        Entry entry = null;
+        String myName = file.getName();
+        for (Entry e : entries) {
+            if (myName.equals(e.getName())) {
+                entry = e;
+                break;
+            }
+        }
+        Dimension orig = entry.getSize();
+        Dimension outd = orig.scaled(size);
+        if (entry.getOrientation() == 6) {
+            outd = outd.flip();
+        }
+
+        Iterator readers = ImageIO.getImageReadersByFormatName("jpg");
+        ImageReader reader = (ImageReader)readers.next();
+        ImageInputStream iis = ImageIO.createImageInputStream(file);
+        reader.setInput(iis, true);
+        ImageReadParam param = reader.getDefaultReadParam();
+        if (true /* subsampling */) {
+            double subSampleScale = (double)outd.getWidth() / orig.getWidth();
+            int subSampling = (int)Math.floor(0.25d/subSampleScale);
+            param.setSourceSubsampling(subSampling, subSampling, 0, 0);
+        }
+        BufferedImage img = reader.read(0, param);
+
+        // Recalculate scale after subsampling was applied
+        double scale;
+        AffineTransform xform;
+        if (entry.getOrientation() == 6) {
+            xform = AffineTransform.getTranslateInstance(outd.getWidth() / 2d, outd.getHeight() / 2d);
+            xform.rotate(Math.PI / 2);
+            scale = (double)outd.getHeight() / img.getWidth();
+            xform.scale(scale, scale);
+            xform.translate(-img.getWidth() / 2d, -img.getHeight() / 2d);
+            
+        } else {
+            scale = (double)outd.getWidth() / img.getWidth();
+            xform = AffineTransform.getScaleInstance(scale, scale);
+        }
+        BufferedImage buf2 = new BufferedImage(outd.getWidth(), outd.getHeight(), img.getType());
+        Graphics2D g2 = buf2.createGraphics();
+        g2.transform(xform);
+        g2.drawImage(img, 0, 0, null);
+
+        Iterator writers = ImageIO.getImageWritersByFormatName("jpg");
+        ImageWriter writer = (ImageWriter)writers.next();
+        ImageOutputStream ios = ImageIO.createImageOutputStream(res.getOutputStream());
+        writer.setOutput(ios);
+        writer.write(buf2);
+    }
+
+
+    @Override
+    public String getServletInfo() {
+        return "Display a directory as an org.forkalsrud.album";
+    }
+
+}
+
+// eof