Knowledge about arraylist and map

October 17, 2014 16:39:01

1. How to obtain the index value of a data entry in the arraylist?

In the arraylist of Multiple object stores, if you only know one of the attributes of an object, how do you get the index value of this object in the arraylist?

For example, a person class has three attributes (string name, string sex, int age)
Person p1 = new person ("Zhang San", "male", 20 );
Person P2 = new person ("Li Si", "male", 22 );
Person P3 = new person ("Wang Wu", "male", 24 );

Then these objects are stored in the arraylist set. If you only know the name "Li Si" (without knowing the gender and age ), how to obtain the index value (1) of the "Li Si" object in the arraylist set )?

Solution:

For (INT I = 0; I <list. size (); I ++) {If ("Li Si ". ES (list. get (I ). getname () {return I; // I is the index }}

 

Knowledge about arraylist and map