은은하게 코드 뿌시기

컬렉션프레임웍(Collections Framework) - Arrays 클래스 본문

자바/Collections Framework

컬렉션프레임웍(Collections Framework) - Arrays 클래스

은은하게미친자 2022. 10. 1. 21:20
728x90

 

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
package data_structure;
 
 
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.LinkedList;
import java.util.List;
import java.util.Queue;
import java.util.Stack;
 
class code1_ArraysClass {
    public static void main(String[] args) {
        System.out.println("array test");
 
        int[] arr1= {1,2,30,5,4,7,8,10,2};
        int[] arr2= {1,2,999,5,4,7,8,10,2};
        Integer[] arr3 = new Integer[arr1.length];
        int[][] arr4= {{1,2,3,4},{1,2,999,5,4,7,8,10,2}};
        //tostring, deepToString
        System.out.println(Arrays.toString(arr1));
        System.out.println(Arrays.deepToString(arr4));
        // 두배열 같은지 비교하기 다차원 배열은 deepEquals
        System.out.println(Arrays.equals(arr1, arr2));
        // 배열복사
        arr2 = Arrays.copyOf(arr1, arr1.length);
        System.out.println(Arrays.equals(arr1, arr2));
        // 배열 원하는 만큼만 복사
        arr2 = Arrays.copyOfRange(arr1, 5,arr1.length);
        System.out.println(Arrays.toString(arr2));
        // 배열정렬
        Arrays.sort(arr2);
        System.out.println(Arrays.toString(arr2));
        // 리스트로 변환하기 
        List<Object> list = new ArrayList(Arrays.asList(arr2));
        System.out.println("list " + list.toString());
 
        // 배열 이진탐색 반반나눠서 탐색 , 이진탐색은 sort된 값에서 조회 
        System.out.println( Arrays.binarySearch(arr2,10) );
        
        int i=0;
        for (int a : arr1) {
            arr3[i] = Integer.valueOf(a);
            i++;
        }
        System.out.println("copy Integer: " +Arrays.toString(arr3));
        // 배열정렬 내림차순
        Arrays.sort(arr3, Collections.reverseOrder());
        System.out.println(Arrays.toString(arr3));
        
        // 배열값 특정값으로 초기화
        Arrays.fill(arr2, 100);
        System.out.println(Arrays.toString(arr2));
    }
}
 
 
 
 
 
 cs

 

 

728x90

'자바 > Collections Framework' 카테고리의 다른 글

컬렉션프레임웍(Collections Framework) - 큐(Queue)  (0) 2022.10.02
컬렉션프레임웍(Collections Framework) - 스택(stack)  (0) 2022.10.02
컬렉션프레임웍(Collections Framework) - ArrayList  (0) 2022.10.02
컬렉션프레임웍(Collections Framework) - HashSet  (0) 2022.10.02
컬렉션 프레임웍(collections framework) - list,set,map  (0) 2022.08.09
'자바/Collections Framework' Related Articles more
Comments