Question

I am trying to format Date to get a Date of a specific format. However it is not working. Don’t know why! Here is what I did:

           for(LeaveApply leaveApply : leaveApplyList) {
                SimpleDateFormat dateFormat = new SimpleDateFormat("dd-MM-yyyy");
                try {
                    leaveApply.setDate(dateFormat.parse(dateFormat.format(leaveApply.getDate())));
                } catch (ParseException e) {
                    e.printStackTrace();
                }
            }

The output is :

LeaveApply [id=1, user=id [1]; loginName [admin], leaveType=Medical Leave, leaveTime=Half Leave, date=Fri Apr 15 00:00:00 IST 2011]
LeaveApply [id=0, user=id [1]; loginName [admin], leaveType=Weekend, leaveTime=Full Leave, date=Sat Apr 02 00:00:00 IST 2011]
LeaveApply [id=0, user=id [1]; loginName [admin], leaveType=Weekend, leaveTime=Full Leave, date=Sun Apr 03 00:00:00 IST 2011]
LeaveApply [id=0, user=id [1]; loginName [admin], leaveType=Weekend, leaveTime=Full Leave, date=Sat Apr 09 00:00:00 IST 2011]
LeaveApply [id=0, user=id [1]; loginName [admin], leaveType=Weekend, leaveTime=Full Leave, date=Sun Apr 10 00:00:00 IST 2011]
LeaveApply [id=0, user=id [1]; loginName [admin], leaveType=Weekend, leaveTime=Full Leave, date=Sat Apr 16 00:00:00 IST 2011]
LeaveApply [id=0, user=id [1]; loginName [admin], leaveType=Weekend, leaveTime=Full Leave, date=Sun Apr 17 00:00:00 IST 2011]
LeaveApply [id=0, user=id [1]; loginName [admin], leaveType=Weekend, leaveTime=Full Leave, date=Sat Apr 23 00:00:00 IST 2011]
LeaveApply [id=0, user=id [1]; loginName [admin], leaveType=Weekend, leaveTime=Full Leave, date=Sun Apr 24 00:00:00 IST 2011]
LeaveApply [id=0, user=id [1]; loginName [admin], leaveType=Weekend, leaveTime=Full Leave, date=Sat Apr 30 00:00:00 IST 2011]

As you can see the date is not in desired format (dd-MM-yyyy). Any help will be appreciable.
The LeaveApply class is :

public class LeaveApply implements Serializable {

    private static final long serialVersionUID = -7223672229309295181L;
    private long id;
    private User user;
    private String leaveType;
    private String leaveTime;
    private Date date;

    public LeaveApply() {

    }

    public LeaveApply(User user, String leaveType, String leaveTime, Date date) {
        super();
        this.user = user;
        this.leaveType = leaveType;
        this.leaveTime = leaveTime;
        this.date = date;
    }    

    public long getId() {
        return id;
    }

    public void setId(long id) {
        this.id = id;
    }

    public User getUser() {
        return user;
    }

    public void setUser(User user) {
        this.user = user;
    }

    public String getLeaveType() {
        return leaveType;
    }

    public void setLeaveType(String leaveType) {
        this.leaveType = leaveType;
    }

    public String getLeaveTime() {
        return leaveTime;
    }

    public void setLeaveTime(String leaveTime) {
        this.leaveTime = leaveTime;
    }

    public Date getDate() {
        return date;
    }

    public void setDate(Date date) {
        this.date = date;
    }

    @Override
    public String toString() {
        return "LeaveApply [id=" + id + ", user=" + user + ", leaveType=" + leaveType + ", leaveTime=" + leaveTime + ", date=" + date + "]";
    }    
}

And I am printing the list as :

for (LeaveApply leaveApply : leaveApplyList) {
        System.out.println(leaveApply);
}

Answer 1

You need to use the SimpleDateFormat to format the string when you print it. What your code does now is:

• get a timestamp
• format it
• parse the formatted string back to a timestamp
• set the timestamp

Which is a rather expensive no-op, as a Date object only contains a long representing the timestamp, no formatting information.

Further on, where you print the timestamp, you use the default date format. You should use your date formatted at that point instead.