The arraylist object is a collection of items containing a single data value 數(shù)組列表對(duì)象為一組包含單一數(shù)據(jù)值的集合。
Instead of creating a field that returns an array of typed objects , however , you can create a field that returns a single 但是,不是創(chuàng)建返回類型化對(duì)象數(shù)組的字段,而是可以創(chuàng)建返回單個(gè)arraylist的字段。
We start by forming an arraylist containing a set of arraylists , in which each of the constituent arraylists contains exactly one element of the first permutation group 我們開始形成包含一組arraylists的arraylist ,在其中,每個(gè)構(gòu)成的arraylists正好包含第一個(gè)置換群的一個(gè)元素。
Then , a new arraylist is created which contains the cross product of the contents of each of the constituent arraylists of the super - arraylist with all of the elements in the second permutation group 然后,建立一個(gè)新的arraylist ,它包含每個(gè)(超級(jí)arraylist的)構(gòu)成的arraylists的內(nèi)容和第二個(gè)置換群的所有單元的向量積。