1, an array of introduction
Because arrays are sequentially stored in the data storage, the memory is stored in continuous, which is characterized by the data easier to read
, difficult to remove insert
Analysis 2.arraylist source
1) the constructor (the default capacity of 10)
2) inserting a data
expansion operation newCapacity = oldCapacity + oldCapacity >> 1
3) delete operation
4) traversal
arraylist remove elements during traversal being given
for (Integer NUM: List) {
IF (== 12 is NUM)
list.remove ();
}
Iterator can be deleted by
the Iterator <Integer> = list.iterator IT ();
the while (it.hasNext ()) {
Integer it.next NUM = ();
IF (== 12 is NUM) {
it.remove () ;
}
}