[java] Get yesterday's date using Date

The following function produces today's date; how can I make it produce only yesterday's date?

private String toDate() {
        DateFormat dateFormat = new SimpleDateFormat("yyyy/MM/dd HH:mm:ss");
        Date date = new Date();    
        return dateFormat.format(date).toString();
}

This is the output:

2012-07-10

I only need yesterday's date like below. Is it possible to do this in my function?

2012-07-09

Try this;

   public String toDate() {
       DateFormat dateFormat = new SimpleDateFormat("yyyy/MM/dd HH:mm:ss");
       Calendar cal = Calendar.getInstance();
       cal.add(Calendar.DATE, -1);
       return dateFormat.format(cal.getTime());
  }

changed from your code :

private String toDate(long timestamp) {
    Date date = new Date (timestamp * 1000 -  24 * 60 * 60 * 1000);
   return new SimpleDateFormat("yyyy-MM-dd").format(date).toString();

}

but you do better using calendar.

Calendar cal = Calendar.getInstance();
   DateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd");
   System.out.println("Today's date is "+dateFormat.format(cal.getTime()));

   cal.add(Calendar.DATE, -1);
   System.out.println("Yesterday's date was "+dateFormat.format(cal.getTime())); 

You can do following:

private Date getMeYesterday(){
     return new Date(System.currentTimeMillis()-24*60*60*1000);
}

Note: if you want further backward date multiply number of day with 24*60*60*1000 for example:

private Date getPreviousWeekDate(){
     return new Date(System.currentTimeMillis()-7*24*60*60*1000);
}

Similarly, you can get future date by adding the value to System.currentTimeMillis(), for example:

private Date getMeTomorrow(){
     return new Date(System.currentTimeMillis()+24*60*60*1000);
}

   Calendar cal = Calendar.getInstance();
   DateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd");
   System.out.println("Today's date is "+dateFormat.format(cal.getTime()));

   cal.add(Calendar.DATE, -1);
   System.out.println("Yesterday's date was "+dateFormat.format(cal.getTime()));  

Use Calender Api

Try this one:

private String toDate() {
    DateFormat dateFormat = new SimpleDateFormat("yyyy/MM/dd HH:mm:ss");

    // Create a calendar object with today date. Calendar is in java.util pakage.
    Calendar calendar = Calendar.getInstance();

    // Move calendar to yesterday
    calendar.add(Calendar.DATE, -1);

    // Get current date of calendar which point to the yesterday now
    Date yesterday = calendar.getTime();

    return dateFormat.format(yesterday).toString();
}

There is no direct function to get yesterday's date.

To get yesterday's date, you need to use Calendar by subtracting -1.