1,HTML source code£º <html> <head> <title>How to use SortedMap</title> </head> <body> <script src="jsjava.js"></script> <script> var h=new TreeMap(); h.put("a","b"); h.put("c","d"); h.put("b","e"); h.put("null","a"); h.put(new Integer(9),"e"); document.write(h.get("c")+"<br>"); document.write(h.get("none")+"<br>"); document.write(h.containsKey(new Integer(7))+"<br>"); var keys=h.keys(); while(keys.hasMoreElements()){ document.write(keys.nextElement()+","); } </script> </body> </html> 2,The display:

d undefined false 9,a,b,c,null,