Java Learning Note 27

Vector is the implementation class of the list interface, supports all functions of the list interface, the vector class is an array-based implementation of the list class, in the internal encapsulation of a dynamic,

Allow redistribution of the object[] array, vector is thread-safe, without the need for a program to ensure the synchronization of the collection.

The following is a description of the methods used by the vector class:

public class Main {public static void Main (string[] args) {vector vector=new vector (); ArrayList list=new ArrayList () list.add ("BILL"); Vector.add (list);//output: [[Bill]]system.out.println (vector);//  Output: Vector Capacity: 10system.out.println ("Vector Volume:" +vector.capacity ());/* * Increase the capacity of this vector (if necessary) to ensure that it can hold at least the number of components specified by the minimum capacity parameter. * If the current capacity of this vector is less than mincapacity, increase its capacity by replacing its internal data array (saved in field Elementdata) with a larger array. The size of the new data array will be the original size plus capacityincrement, * unless the capacityincrement value is less than or equal to zero, in the latter case the new capacity will be twice times the original capacity, * However, if this size is still less than mincapacity,  The new capacity will be mincapacity. */vector.ensurecapacity (21);//output: Vector Volume: 21system.out.println ("Vector Volume:" +vector.capacity ()); Vector vector1=new vector (), Vector1.add (list),/* * If the specified Object is equal to this vector, returns True */system.out.println (Vector.equals (  Vector1));//output: true/* * Returns the item at the first component of this vector (at index 0).  */system.out.println (Vector.firstelement ());//output: [bill]/* * Returns the element at the specified position in the vector. * If the index is out of range (Index < 0 | | index >= size ()), throw arrayindexoutofboundsexception exception */system.out.println (vector.get (0)) ;//output: [bill]/* * Returns the hash code for this vectorValue. */system.out.println (Vector.hashcode ()); Vector.add ("Jack"); Vector.add ("Marray"); Vector.add ("Jack");//output: [[BILL ], JACK, Marray, jack]system.out.println (vector); * * Returns the index of the specified element that first appears in this vector, or 1 if the vector does not contain the element.  To be more exact, * Returns the lowest index of the satisfied (o==null. Get (i) ==null:o.equals (get (i))) and returns-1 if there is no such index. */system.out.println (Vector.indexof ("JACK"));//output: 1/* * Returns the index of the specified element that first appears in this vector, and a forward search from index, * returns 1 if the element is not found. * If the specified index is negative, throw indexoutofboundsexception exception */system.out.println (Vector.indexof ("JACK", 2));//output: 3/* * Inserts the specified object as a component in this vector at the specified index. * Each index in this vector that is greater than or equal to the specified index will be shifted upward, making its index value 1 larger than the previous value.  The index must be a value greater than or equal to 0 and * less than or equal to the current size of the vector (if the index equals the current size of the vector, * adds the new element to the vector). * If the index is out of range (Index < 0 | | index > Size ()), throw arrayindexoutofboundsexception exception */vector.insertelementat ("WORD", 1);// Output: [[BILL], WORD, JACK, Marray, jack]system.out.println (vector),/* * Returns TRUE if and only if this vector has no component (that is, its size is 0); */system.out.println (Vector.isempty ());//output: false/* * Returns the index of the last occurrence of the specified element in this vector, or 1 if the vector does not contain the element. To be more exact, * Return to meet (o==null ?  The highest index i * for Get (i) ==null:o.equals (get (i)), or 1 if there is no such index. */system.out.println (Vector.lastindexof ("JACK"));//output: 4/* * Removes the element at the specified position in this vector. Shifts all subsequent elements to the left (index minus 1).  Returns the element that is removed from this vector. * If the index is out of range (Index < 0 | | index >= size ()), throw arrayindexoutofboundsexception exception */vector.remove (0);//output: [WORD, JACK, M ARRAY, jack]system.out.println (vector);/* Removes the first occurrence of the specified element in this vector, and if the vector does not contain the element, the element remains unchanged.  * To be more exact, remove the element whose index I satisfies (o==null. Get (i) ==null:o.equals (get (i))) * (if such an element exists). */system.out.println (Vector.remove ("WORD")); System.out.println (vector);//output: [Jack, Marray, Jack]}}

For more information on vectors, see the following articles

Reprint Please specify source:http://blog.csdn.net/hai_qing_xu_kong/article/details/44106381 Emotional Control _  

Java Learning Note 27