LoggingPanel: use colors to visualize log levels

Author: maarzt

src/main/java/org/scijava/ui/swing/console/LoggingPanel.java

@@ -33,8 +33,10 @@
 import java.awt.*;
 
 import javax.swing.*;
+import javax.swing.text.AttributeSet;
 import javax.swing.text.BadLocationException;
-import javax.swing.text.Style;
+import javax.swing.text.MutableAttributeSet;
+import javax.swing.text.SimpleAttributeSet;
 import javax.swing.text.StyleConstants;
 import javax.swing.text.StyledDocument;
 
@@ -46,6 +48,7 @@
 import org.scijava.log.LogMessage;
 import org.scijava.log.LogService;
 import org.scijava.log.Logger;
+import org.scijava.log.LogLevel;
 import org.scijava.thread.ThreadService;
 import org.scijava.ui.swing.StaticSwingUtils;
 
@@ -64,11 +67,18 @@
 @IgnoreAsCallingClass
 public class LoggingPanel extends JPanel implements LogListener
 {
+	private static final AttributeSet DEFAULT_STYLE = new SimpleAttributeSet();
+	private static final AttributeSet STYLE_ERROR = normal(new Color(200, 0, 0));
+	private static final AttributeSet STYLE_WARN = normal(new Color(200, 140, 0));
+	private static final AttributeSet STYLE_INFO = normal(Color.BLACK);
+	private static final AttributeSet STYLE_DEBUG = normal(new Color(0, 0, 200));
+	private static final AttributeSet STYLE_TRACE = normal(Color.GRAY);
+	private static final AttributeSet STYLE_OTHERS = normal(Color.GRAY);
+
 	private JTextPane textPane;
 	private JScrollPane scrollPane;
 
 	private StyledDocument doc;
-	private Style defaultStyle;
 
 	private final LogFormatter formatter = new LogFormatter();
 
@@ -87,12 +97,12 @@ public void clear() {
 
 	@Override
 	public void messageLogged(LogMessage message) {
-		appendText(formatter.format(message), defaultStyle);
+		appendText(formatter.format(message), getLevelStyle(message.level()));
 	}
 
 	// -- Helper methods --
 
-	private void appendText(final String text, final Style style) {
+	private void appendText(final String text, final AttributeSet style) {
 		threadService.queue(new Runnable() {
 
 			@Override
@@ -119,8 +129,6 @@ private synchronized void initGui() {
 
 		doc = textPane.getStyledDocument();
 
-		defaultStyle = createStyle("stdoutLocal", null, Color.black, null, null);
-
 		// NB: We wrap the JTextPane in a JPanel to disable
 		// the text pane's intelligent line wrapping behavior.
 		// I.e.: we want console lines _not_ to wrap, but instead
@@ -143,13 +151,32 @@ private synchronized void initGui() {
 		add(scrollPane);
 	}
 
-	private Style createStyle(final String name, final Style parent,
-							  final Color foreground, final Boolean bold, final Boolean italic)
-	{
-		final Style style = textPane.addStyle(name, parent);
-		if (foreground != null) StyleConstants.setForeground(style, foreground);
-		if (bold != null) StyleConstants.setBold(style, bold);
-		if (italic != null) StyleConstants.setItalic(style, italic);
+	private static AttributeSet getLevelStyle(int i) {
+		switch (i) {
+			case LogLevel.ERROR:
+				return STYLE_ERROR;
+			case LogLevel.WARN:
+				return STYLE_WARN;
+			case LogLevel.INFO:
+				return STYLE_INFO;
+			case LogLevel.DEBUG:
+				return STYLE_DEBUG;
+			case LogLevel.TRACE:
+				return STYLE_TRACE;
+			default:
+				return STYLE_OTHERS;
+		}
+	}
+
+	private static MutableAttributeSet normal(Color color) {
+		MutableAttributeSet style = new SimpleAttributeSet();
+		StyleConstants.setForeground(style, color);
+		return style;
+	}
+
+	private static MutableAttributeSet italic(Color color) {
+		MutableAttributeSet style = normal(color);
+		StyleConstants.setItalic(style, true);
 		return style;
 	}