Why not add a Timestamp to Arraylist inside a variable of type

Such as:

List objList = null;
objList = new ArrayList ();
Timestamp a = General.ToDate (General.convertStringToDate (m, "yyyy-MM-dd"));
objList.add (a);
objList.add (General.convertDateToTimestamp (General.convertStringToDate (m, "yyyy-MM-dd")));

above two methods which add to objList not work, I can add the application tracking type String , is not add Timestamp type, seeking god help the next Manga, first thanked you for the.
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add the parameter type is Object, can be added . You see if it is another error.
------ Solution ---------------------------------------- ----
your problems elsewhere , right ?

  import java.sql.Timestamp;
  import java.util.ArrayList;
  import java.util.Date;
  import java.util.List;
  
  public class ListTest {
  
  	/**
  	 * @param args
  	 */
  	public static void main(String[] args) {
  		// TODO Auto-generated method stub
  
  		
  		List objList = null;
  		objList = new ArrayList();
  		Timestamp a = new Timestamp(new Date().getTime());
  		objList.add(a);
  	}
  
  }
  
  

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with generics

List list = new ArrayList ();
Date date = new Date ();
Timestamp time = new Timestamp (date.getTime ());
list.add (time);
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is not your time packet error import it ?
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been resolved, thank you ah
Error:
my program m = '2012 Year March 22 ' ;
General.convertStringToDate (m, "yyyy-MM-dd")
conversion error saying it can not be converted , in the preceding first m converted to '2012 -03-22 ' format just fine.

now do not understand is why there can not be directly converted to m . But the program has been good .
Thank you ah