@@ -0,0 +1,633 @@
+public class ReplaceBlank %7B%0A    public String replaceSpace(StringBuffer str) %7B%0A        StringBuffer sb = new StringBuffer();%0A    %09if(str.length()==0)%0A            return sb.toString();%0A        for(int i=0; i%3Cstr.length(); i++)%7B%0A            if(str.charAt(i)==' ')%7B%0A                sb.append(%22%2520%22);%0A            %7D%0A            else%0A                sb.append(str.charAt(i));%0A        %7D%0A        return sb.toString();%0A    %7D%0A    %0A    public static void main(String%5B%5D args)%7B%0A        StringBuffer str = new StringBuffer(%22We are Happy.%22);%0A        String result = new ReplaceBlank().replaceSpace(str);%0A        System.out.println(result);%0A    %7D%0A%7D%0A

Create ReplaceBlank.java