I think I fixed it.. The image scaling issue

Added prototype for media descriptions

ComposeWindow.java

@@ -130,7 +130,9 @@ ComposeWindow extends JFrame {
 			if (a.id != null) continue;
 			// Assume it had already been uploaded.
 
-			api.uploadFile(a.uploadee, new RequestListener() {
+			api.uploadFile(
+				a.uploadee, a.description,
+				new RequestListener() {
 
 				public void
 				connectionFailed(IOException eIo)
@@ -561,9 +563,6 @@ implements ActionListener {
     private JPanel
     selections;
 
-    private ButtonGroup
-    selectionsGroup;
-
     private JToggleButton
     attachment1,
     attachment2,
@@ -621,29 +620,29 @@ implements ActionListener {
 
         if (working.size() > 3)
 		{
-			attachment4.doClick();
 			Image i = working.get(3).image;
 			attachment4.setIcon(new ImageIcon(i));
 		}
         else if (working.size() > 2)
 		{
-			attachment3.doClick();
 			Image i = working.get(2).image;
 			attachment3.setIcon(new ImageIcon(i));
 		}
         else if (working.size() > 1)
 		{
-			attachment2.doClick();
 			Image i = working.get(1).image;
 			attachment2.setIcon(new ImageIcon(i));
 		}
         else if (working.size() > 0)
 		{
-			attachment1.doClick();
 			Image i = working.get(0).image;
 			attachment1.setIcon(new ImageIcon(i));
 		}
-        else selectionsGroup.clearSelection();
+
+		attachment4.setSelected(working.size() > 3);
+		attachment3.setSelected(working.size() > 2);
+		attachment2.setSelected(working.size() > 1);
+		attachment1.setSelected(working.size() > 0);
 
         int bw = sz.width;
         int hgap = 4;
@@ -661,11 +660,6 @@ implements ActionListener {
     {
         Object src = eA.getSource();
 
-        if (false)
-        {
-            // Clicked on filled attachment button.
-        }
-
         if (src == add)
         {
 			int r = chooser.showOpenDialog(this);
@@ -697,40 +691,93 @@ implements ActionListener {
 
         if (src == delete)
         {
-            Object sm = selectionsGroup.getSelection();
-            if (sm == attachment1.getModel())
+            if (attachment1.isSelected())
             {
                 assert working.size() > 0;
                 working.remove(0);
-                updateButtons();
             }
-            if (sm == attachment2.getModel())
+            if (attachment2.isSelected())
             {
                 assert working.size() > 1;
                 working.remove(1);
-                updateButtons();
             }
-            if (sm == attachment3.getModel())
+            if (attachment3.isSelected())
             {
                 assert working.size() > 2;
                 working.remove(2);
-                updateButtons();
             }
-            if (sm == attachment4.getModel())
+            if (attachment4.isSelected())
             {
                 assert working.size() > 3;
                 working.remove(3);
-                updateButtons();
             }
+			updateButtons();
             return;
         }
 
+		if (src != add && selections.isAncestorOf((Component)src))
+		{
+			int iCurr = getSelectedIndex();
+			int iNext = getIndex(src);
+			System.err.println(iCurr + ":" + iNext);
+			assert iNext != 0;
+			if (iCurr == iNext) {
+				save();
+				return;
+			}
+			if (iCurr != 0) save();
+			load(iNext);
+		}
+
         if (src == revert)
         {
-            return;
+			assert getSelectedIndex() != 0;
+			// Should the controls be disabled until
+			// there is an attachment?
+			load(getSelectedIndex());
         }
     }
 
+	private int
+	getIndex(Object src)
+	{
+		if (src == attachment4) return 4;
+		if (src == attachment3) return 3;
+		if (src == attachment2) return 2;
+		if (src == attachment1) return 1;
+		return 0;
+	}
+
+	private int
+	getSelectedIndex()
+	{
+		if (attachment4.isSelected()) return 4;
+		if (attachment3.isSelected()) return 3;
+		if (attachment2.isSelected()) return 2;
+		if (attachment1.isSelected()) return 1;
+		return 0;
+	}
+
+	private void
+	save()
+	{
+		int index = getSelectedIndex();
+		assert index != 0;
+
+		Attachment a = working.get(index - 1);
+		a.description = this.description.getText();
+	}
+
+	private void
+	load(int index)
+	{
+		assert index > 0;
+		assert working.size() >= index;
+
+		Attachment a = working.get(index - 1);
+		this.description.setText(a.description);
+	}
+
 //  ---%-@-%---
 
     AttachmentsComponent(ComposeWindow primaire)
@@ -762,17 +809,20 @@ implements ActionListener {
         attachment2.setMargin(add.getMargin());
         attachment3.setMargin(add.getMargin());
         attachment4.setMargin(add.getMargin());
+		attachment1.addActionListener(this);
+		attachment2.addActionListener(this);
+		attachment3.addActionListener(this);
+		attachment4.addActionListener(this);
 
         selections = new JPanel();
         selections.setOpaque(false);
         selections.setLayout(new GridLayout(1, 0, 4, 0));
         working = new ArrayList<Attachment>();
-        selectionsGroup = new ButtonGroup();
+        ButtonGroup selectionsGroup = new ButtonGroup();
         selectionsGroup.add(attachment1);
         selectionsGroup.add(attachment2);
         selectionsGroup.add(attachment3);
         selectionsGroup.add(attachment4);
-        // Have to add selection listener to button group
         updateButtons();
 
         JButton del = new JButton("D");

ImageApi.java

@@ -2,6 +2,11 @@
 import javax.swing.ImageIcon;
 import java.awt.Image;
 import java.awt.Toolkit;
+import java.awt.MediaTracker;
+import java.awt.Graphics;
+import java.awt.Component;
+import java.awt.image.ImageObserver;
+import java.awt.image.BufferedImage;
 import java.net.URL;
 import java.net.MalformedURLException;
 

MastodonApi.java

@@ -435,9 +435,10 @@ MastodonApi {
     }
 
     public void
-    uploadFile(File file, RequestListener handler)
+    uploadFile(File file, String alt, RequestListener handler)
     {
         assert file != null;
+		assert alt != null;
         assert file.canRead();
 
         String bct =
@@ -496,10 +497,12 @@ MastodonApi {
         String url = instanceUrl + "/api/v1/media/";
         try
         {
-			URL endpoint = new URL(url);
+			String s1 = "?description=" + encode(alt);
+
+			URL endpoint = new URL(url + s1);
             HttpURLConnection conn = cast(endpoint.openConnection());
-            String s1 = "Bearer " + token;
-            conn.setRequestProperty("Authorization", s1);
+            String s2 = "Bearer " + token;
+            conn.setRequestProperty("Authorization", s2);
             conn.setDoOutput(true);
             conn.setRequestMethod("POST");
 			conn.setFixedLengthStreamingMode(contentLength);

PostWindow.java

@@ -429,54 +429,7 @@ implements ActionListener {
     setAuthorId(String n) { authorId.setText(n); }
 
 	public void
-	setAuthorAvatar(Image n)
-	{
-		try {
-			MediaTracker mt = new MediaTracker(this);
-			mt.addImage(n, 0);
-			mt.waitForID(0);
-		}
-		catch (InterruptedException eIt) {
-			assert false;
-		}
-		/*
-		* Blocks until the image loads. We have to do this because
-		* there is an unfixed JDK bug in Image#getScaledInstance
-		* (which RoundButton uses) where when you pass it an AWT
-		* image, it incorrectly sets the ColorModel's transfer type,
-		* causing a ClassCastException, and returns a valid image
-		* with blank data. It seems using loaded images does not
-		* replicate the issue, which would explain why the bug
-		* hasn't been found and fixed..
-		*
-		* For future readers wondering. JDK 11, up to JDK 15.
-		* java.awt.image.ColorModel#getAlpha(:845), who was called
-		* sun.awt.image.ImageRepresentation#convertToRGB, who was
-		* called by AreaAveragingScaleFilter trying to #setPixels.
-		* Cause RoundButton was using Image.SCALE_SMOOTH.
-		*
-		* I guess it kind of makes sense, why would I try to get a
-		* scaled instance of an image that hadn't finished loading.
-		* An intelligent class would render the awt.Image as-is until
-		* it has completely loaded, then call #getScaledInstance
-		* instead. I won't have RoundButton do that for now, as
-		* my other classes like RichTextPane3 might have this too.
-		*
-		* If you asked me how I'd generalise the solution. My
-		* expectation had been that #getScaledInstance waits for
-		* the image too, returning a null image until it's done.
-		* So I'd put a #getScaledInstance in ImageApi, which does
-		* this, using MediaTracker. That assumes what I'm doing
-		* right now definitely works.
-		*/
-		/*
-		* (悪) It doesn't work. I might be forced to use
-		* BufferedImage with ImageIO. Or have
-		* ImageApi#getScaledInstance spam until it works.
-		*/
-
-		profile.setImage(n);
-	}
+	setAuthorAvatar(Image n) { profile.setImage(n); }
 
     public void
     setDate(String n) { date.setText(n); }

TwoToggleButton.java

@@ -8,6 +8,8 @@ import java.awt.Graphics;
 import java.awt.Dimension;
 import java.awt.Shape;
 import java.awt.Rectangle;
+import java.awt.Component;
+import java.awt.image.BufferedImage;
 import java.awt.geom.Ellipse2D;
 import java.awt.event.MouseListener;
 import java.awt.event.MouseEvent;
@@ -255,6 +257,7 @@ implements KeyListener, MouseListener, FocusListener {
 //	 -	-%-	 -
 
 	private Image
+	copy,
 	scaled;
 
 	private int
@@ -267,22 +270,78 @@ implements KeyListener, MouseListener, FocusListener {
     selectedOverlay,
     disabledOverlay;
 
+	private static Shape
+	roundClip;
+
 //  ---%-@-%---
 
 	public void
 	setImage(Image n)
 	{
 		image = n;
+		copy = null;
 		scaled = null;
+
+		if (image != null)
+		{
+			image.flush();
+			prepareImage(image, this);
+		}
 	}
 
 //	 -	-%-	 -
 
 	public boolean
-	imageUpdate(Image i, int f, int x, int y, int w, int h)
+	imageUpdate(Image img, int f, int x, int y, int w, int h)
 	{
-		if ((f | WIDTH) != 0) repaint();
-		return super.imageUpdate(i, f, x, y, w, h);
+     	// AbstractButton overrode this to refuse updates for
+		// images that aren't the button's icon. We don't use
+		// the icon, so we're overriding it back. Also, we have
+		// some async work to do regarding the images.
+		
+		if ((f & (ABORT|ERROR)) != 0) return false;
+
+		boolean all = (f & ALLBITS) != 0;
+		boolean frame = (f & FRAMEBITS) != 0;
+		boolean some = (f & SOMEBITS) != 0;
+
+		if (frame && img != this.image) return false;
+
+		if (img == this.image && (all || frame))
+		{
+			int ow = img.getWidth(null);
+			int oh = img.getHeight(null);
+
+			if (copy == null)
+			{
+				int type = BufferedImage.TYPE_INT_ARGB;
+				copy = new BufferedImage(ow, oh, type);
+			}
+
+			Graphics g = copy.getGraphics();
+			g.drawImage(img, 0, 0, null);
+			g.dispose();
+
+			int algo = Image.SCALE_SMOOTH;
+			Rectangle b = roundClip.getBounds();
+			int sw = ow > oh ? -1 : b.width;
+			int sh = oh > ow ? -1 : b.height;
+			scaled = copy.getScaledInstance(sw, sh, algo);
+			/*
+			* We create a scaled instance from a BufferedImage copy
+			* rather than this.image directly, to avoid a ClassCast
+			* Exception bug in the JDK, where ColorModel was
+			* incorrectly casting an int array of input data into
+			* a byte array. I'm not sure why that bug exists nor
+			* why they haven't noticed it, but.
+			*/
+			repaint();
+		}
+		if (img == scaled && (some || all))
+		{
+			repaint();
+		}
+		return all ? false : true;
 	}
 
     protected void
@@ -294,34 +353,13 @@ implements KeyListener, MouseListener, FocusListener {
 		if (isFocusOwner())
             g.drawImage(selectedOverlay, 0, 0, this);
 
-        if (image == null) return;
-
-		int ow = image.getWidth(this);
-		int oh = image.getHeight(this);
-		int nx = 6;
-		int ny = 6;
-		int nw = button.getWidth(this) - 12;
-		int nh = button.getHeight(this) - 12;
-		Shape defaultClip, roundClip;
-		defaultClip = g.getClip();
-		roundClip = new Ellipse2D.Float(nx, ny, nw, nh);
-
-		if (scaled == null)
-		{
-			int sw = ow > oh ? -1 : nw;
-			int sh = oh > ow ? -1 : nh;
-			// We do not defend against unloaded images. There is
-			// a bug on those anyways, see comment in PostWindow.
-			scaled = image.getScaledInstance(
-				sw, sh,
-				Image.SCALE_SMOOTH
-			);
-		}
-		// (知) Be careful to be idempotent when calling
-		// async methods like #drawImage.
+		if (scaled == null) return;
 
+		Rectangle b = roundClip.getBounds();
+		Shape defaultClip = g.getClip();
 		g.setClip(roundClip);
-		g.drawImage(scaled, nx, ny, getParent());
+		g.drawImage(scaled, b.x, b.y, this);
+		getParent().repaint();
 		// I don't know why, but when we repaint ourselves, our
 		// parent doesn't repaint, so nothing seems to happen.
 		g.setClip(defaultClip);
@@ -383,8 +421,8 @@ implements KeyListener, MouseListener, FocusListener {
 		setFocusable(true);
 		setOpaque(false);
 
-        int w = button.getWidth(this);
-        int h = button.getHeight(this);
+        int w = button.getWidth(null);
+        int h = button.getHeight(null);
         setPreferredSize(new Dimension(w, h));
 
         this.addKeyListener(this);
@@ -405,6 +443,14 @@ implements KeyListener, MouseListener, FocusListener {
         button = new ImageIcon(u1).getImage();
         disabledOverlay = new ImageIcon(u2).getImage();
         selectedOverlay = new ImageIcon(u3).getImage();
+
+		int radius = 6;
+		roundClip = new Ellipse2D.Float(
+			radius,
+			radius,
+			button.getWidth(null) - (2 * radius),
+			button.getHeight(null) - (2 * radius)
+		);
     }
 
 }