Re: compering date with the data base

From:

Lew <conrad@lewscanon.com.invalid>

Newsgroups:

comp.lang.java.programmer

Date:

Sun, 25 May 2008 23:16:19 -0400

Message-ID:

<W4-dnaKmVfoZtqfVnZ2dnUVZ_hydnZ2d@comcast.com>

shinshin wrote:

while using an SQL query i [sic] am retreiving the date with the follow
format: mm/dd/yyyy
in date instance.
while using a getstartdate() methos i am geting a calendar object with
the follow data:
mm/dd/yyyy hh:mm how can i compare both dates?

Arne Vajh??j wrote:

You should both retrieve the data from the database and
from the calendar in form of java.util.Date objects and
only format to String when displaying.

shinshin wrote:

2 questions:
1. how do i cast a calendar to date.
2. how can i get only the date without the hh/mm

Arne Vajh??j wrote:

Calendar has a getTime method that returns a Date object.

OP: The Javadocs for Calendar have a summary of all its methods.

Be aware that Calendar#getTime() and Date#getTime() are fundamentally
different. The Javadocs show how.

On the Calendar object you can set hh, mm and ss to 0.

I suggest using java.sql.Date and its siblings to interact with the java.sql
interfaces like PreparedStatement and ResultSet. They are direct subclasse of
java.util.Date, set up specifically for SQL frameworks to recognize.

This is opposite to the usual best practice of using a supertype declaration
whenever feasible, but in this case it is justified. The java.sql type
documents in the code the mapping from SQL to Java, made precise by the choice
of java.sql.Date, Time or Timestamp as the object type.

Put another way, the java.sql classes belong to the data-access ontology, so
it's OK to use them instead of supertypes when in that ontology.

--
Lew