What is the difference between this:
ArrayList<String> test = new ArrayList<String>();
为此:
ArrayList<String> test = new ArrayList<String>(3);
我刚刚测试了Array,我确实看不到任何区别。 我总是看到有人在那里使用一些东西?
Initial Capacity Generally used to create lists with some storage amount ahead of time so java doesn t have to do it for you when you add elements. Or if you know exactly how many entries it will have.
很显然,清单在以这种方式产生时仍然未包含任何内容,但保留这些内容的空间。
It s the initial size of your list. If you don t give any argument, there will be a default intitial size. By the way, reading the Javadoc will answer all those questions.
当你使用第二部法典时,它首先分配3项内容,第1项将分配10项内容(能力)。
Constructs an empty list with an initial capacity of ten.
http://download.oracle.com/javase/6/docs/api/java/util/ArrayList.html
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