Swing is one of the best things that happened to Java GUI developers. At the heart of Swing is the javax.swing.UIManager class (com.sun.java.swing.UIManager for Swing 1.03 and below) that keeps track of the current look and feel and its defaults at three levels: user defaults, look and feel defaults, and system defaults. A call to javax.swing.UIManager.getDefaults() will return an instance of the javax.swing.UIDefaults class, which is an extension of java.util.Hashtable containing the defaults for Swing components. With a few lines of code, you can print out all the keys that represent all the settings for Swing components along with their default values:
public void outputSwingDefs(){ String lineSep = System.getProperty("line.separator"); javax.swing.UIDefaults uid = javax.swing.UIManager.getDefaults(); java.util.Enumeration uidKeys = uid.keys(); java.io.BufferedWriter buff = null; java.io.FileWriter fr=null; try { fr = new java.io.FileWriter("swing_defaults.txt", true); buff = new java.io.BufferedWriter(fr); while (uidKeys.hasMoreElements()) { Object aKey = uidKeys.nextElement(); Object aValue = uid.get(aKey); String str = "KEY: "+aKey+", VALUE: "+aValue+lineSep; buff.write(str, 0, str.length()); } } catch(java.io.IOException ioe) { //deal with exception } finally { try { buff.flush(); buff.close(); fr.close(); } catch(Exception e) { //deal with exception } } }
The output will be a text file called “swing_defaults.txt” in the current directory.In that file, you will see lines like:
KEY: Tree.textBackground, VALUE:javax.swing.plaf.ColorUIResource[r=255,g=255,b=255]
indicating that tree’s text background has RGB value set of (255, 255, 255), or:
KEY: ScrollBar.width, VALUE: 17
indicating that ScrollBar has a default width of 17 pixels.