As per the API doc for java.sql.Date.valueOf, IllegalArgumentException should 
be thrown if the date given is not in the JDBC date escape format 
(yyyy-mm-dd). 
 
The error is not thrown when I enter the value '20009-10-10'. Instead it 
silently stores the value. But later when I do java.sql.toString() 
 
    public static void main(String[] args) { 
        java.sql.Date jsd = java.sql.Date.valueOf("20009-06-26"); 
        System.out.println(jsd); 
 
    } 



 
The above program prints 
*009-06-26 Where '*' is a non-readable character. 

We need fix in valueOf method() to throw the exception if we pass 5 digits to 
the API.

From API
valueOf

public static Date valueOf(String s)

    Converts a string in JDBC date escape format to a Date value.

    Parameters:
        s - a String object representing a date in in the format "yyyy-mm-dd" 
    Returns:
        a java.sql.Date object representing the given date 
    Throws:
        IllegalArgumentException - if the date given is not in the JDBC date escape format (yyyy-mm-dd)