use custom renderer and comparator for download progress

gui/src/main/groovy/com/muwire/gui/DownloadProgressRenderer.groovy

@@ -0,0 +1,40 @@
+package com.muwire.gui
+
+import javax.swing.JComponent
+import javax.swing.JLabel
+import javax.swing.JTable
+import javax.swing.table.DefaultTableCellRenderer
+
+import com.muwire.core.download.Downloader
+
+import net.i2p.data.DataHelper
+
+class DownloadProgressRenderer extends DefaultTableCellRenderer {
+    DownloadProgressRenderer() {
+        setHorizontalAlignment(JLabel.CENTER)
+    }
+    
+    @Override
+    JComponent getTableCellRendererComponent(JTable table, Object value,
+        boolean isSelected, boolean hasFocus, int row, int column) {
+        Downloader d = (Downloader) value
+        int pieces = d.nPieces
+        int done = d.donePieces()
+        int percent = -1
+        if (pieces != 0)
+            percent = (int)(done * 100.0 / pieces)
+        long size = d.pieceSize * pieces
+        String totalSize = DataHelper.formatSize2Decimal(size, false) + "B"
+        setText(String.format("%2d", percent) + "% of ${totalSize} ($done/$pieces pcs)".toString())
+        
+        if (isSelected) {
+            setForeground(table.getSelectionForeground())
+            setBackground(table.getSelectionBackground())
+        } else {
+            setForeground(table.getForeground())
+            setBackground(table.getBackground())
+        }
+        this
+    }
+    
+}

gui/src/main/groovy/com/muwire/gui/DownloaderComparator.groovy

@@ -0,0 +1,13 @@
+package com.muwire.gui
+
+import com.muwire.core.download.Downloader
+
+class DownloaderComparator implements Comparator<Downloader>{
+
+    @Override
+    public int compare(Downloader o1, Downloader o2) {
+        double d1 = o1.donePieces() * 1.0 / o1.nPieces
+        double d2 = o2.donePieces() * 1.0 / o2.nPieces
+        return Double.compare(d1, d2);
+    }
+}