myexception.java

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public class MyException
{
  public static void main(String argv[])
  {
    String str = "2abcde";
    try
    {
      char c = str.charAt(0);
      if(c<'a'||c>'z'||c<'A'||c>'Z')
        throw new FirstLetterException();
    }
    catch(FirstLetterException e)
    {
      System.out.println("This is FirstLetterException");
    }
  }
}
class FirstLetterException extends Exception
{
  public FirstLetterException()
  {
    super("The first char is not a letter");
  }
  public FirstLetterException(String str)
  {
    super(str);
  }
}