1、复制数组
Arrays提供了静态方式System.arraycopy，例子如下：
public class CopyArrays {public static void main(String[] args){int[] i = new int[5];int[] j = new int[15];//填充数组Arrays.fill(i, 10);Arrays.fill(j, 20);System.out.println(Arrays.toString(j));//使用System.arraycopy对i数据进行拷贝复制System.arraycopy(i, 0, j, 0, 3);System.out.println(Arrays.toString(j));}}
结果：[20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20][10, 10, 10, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20, 20]
前三个进行了拷由复制
2、数组元素排序比较
public class CompareArray implements Comparable<CompareArray>{private int i;private int j;public CompareArray(int i,int j){this.i= i;this.j = j;}@Overridepublic int compareTo(CompareArray o) {// TODO Auto-generated method stubreturn i<o.i?-1:i==o.i?0:1;}public String toString(){return "[i="+i+",j="+j+"]";}public static void main(String[] args){Random r = new Random(48);CompareArray[] compareArray = new CompareArray[10];for(int i=0;i<10;i++){compareArray[i]= new CompareArray(r.nextInt(100),r.nextInt(100));}System.out.println(Arrays.toString(compareArray));Arrays.sort(compareArray);System.out.println(Arrays.toString(compareArray));}}
结果：
[[i=68,j=16], [i=31,j=44], [i=77,j=11], [i=22,j=0], [i=87,j=94], [i=83,j=3], [i=40,j=4], [i=62,j=72], [i=69,j=84], [i=26,j=82]][[i=22,j=0], [i=26,j=82], [i=31,j=44], [i=40,j=4], [i=62,j=72], [i=68,j=16], [i=69,j=84], [i=77,j=11], [i=83,j=3], [i=87,j=94]]
3、数组查找
如果数组已经是排好序的，可以使用Arrays.binarySearch()进行快速查找，
