My program is showing warning

Question

hi
i am developing a application using swings(JFrames)
i had written the code it worked fine and no warnings or exceptions while tried to execute in JDK1.4 but when i tried to execute in JDK1.5 or more it is showing following warning messages as follows:
C:\Program Files\Java\jdk1.6.0\bin>javac fn1fast.java
Note: fn1fast.java uses unchecked or unsafe operations.
Note: Recompile with -Xlint:unchecked for details.
C:\Program Files\Java\jdk1.6.0\bin>javac -Xlint fn1fast.java
fn1fast.java:12: warning: [serial] serializable class sample has no definition o
f serialVersionUID
class sample extends JFrame
^
fn1fast.java:128: warning: [unchecked] unchecked call to add(E) as a member of t
he raw type java.util.ArrayList
        al.add(new Character((char)i));
              ^
fn1fast.java:26: warning: [serial] serializable class DNA has no definition of s
erialVersionUID
class DNA extends Panel implements ActionListener
^
fn1fast.java:242: warning: [serial] serializable class home has no definition of
serialVersionUID
class home extends Panel
^
fn1fast.java:277: warning: [serial] serializable class image has no definition o
f serialVersionUID
class image extends Panel implements ActionListener
^
5 warningsbut my program is executing well when i tried to execute inspite of above warnings

Answer 1

thanks for ur suggestions...
--santosh