add toolbar based on JToolBar to mimic look & feel of SQLDev

this way the GUI can be shown outside of the IDE, that simplifies
development

Author: PhilippSalvisberg

sqldev/src/main/java/org/utplsql/sqldev/ui/runner/GradientToolbar.xtend

@@ -0,0 +1,38 @@
+package org.utplsql.sqldev.ui.runner
+
+import java.awt.Color
+import java.awt.GradientPaint
+import java.awt.Graphics
+import java.awt.Graphics2D
+import javax.swing.JToolBar
+
+class GradientToolbar extends JToolBar { 
+	override paintComponent(Graphics g) {
+		// default for non-opaque components
+		if (!opaque) {
+			super.paintComponent(g)
+			return
+		}
+		
+		// paint gradient background from top to bottom
+		val g2d = g as Graphics2D
+		val w = width
+        val h = height
+        val h2 = height / 2 as int
+        val colorTop = new Color(237, 237, 237)
+        val colorMiddle = new Color(244, 244, 244)
+        val colorBottom = new Color(254, 254, 254)
+        val gp1 = new GradientPaint(0, 0, colorTop, 0, h2, colorMiddle)
+        g2d.paint = gp1
+        g2d.fillRect(0, 0, w, h2)
+        val gp2 = new GradientPaint(0, h2, colorMiddle, 0, h, colorBottom)
+        g2d.paint = gp2
+        g2d.fillRect(0, h2, w, h)
+		
+		// do rest, changing opaque to ensure background is not overwritten
+		setOpaque(false)
+		super.paintComponent(g)
+		setOpaque(true)
+	}
+	
+}