10种java数组常用的方法

创建一个数组：

String[] a = new String[5];String[] b = {“a”,”b”,”c”, “d”, “e”};String[] c = new String[]{“a”,”b”,”c”,”d”,”e”};

1、打印数组

我们经常使用for循环或者一些迭代器来打印出数组的所有元素，但我们也可以换个姿势。

int array[] = {1,2,3,4,5};System.out.println(array); //[I@1234be4eString arrStr = Arrays.toString(array);System.out.println(array); //[1,2,3,4,5];

2、创建ArrayList

String[] array = { “a”, “b”, “c”, “d”, “e” };ArrayList<String> arrayList =                         new ArrayList<String>(Arrays.asList(array));System.out.println(arrayList);// [a, b, c, d, e]

3、检查是否包含某个值

int array[] = {1,2,3,4,5};boolean isContain= Arrays.asList(array).contains(5);System.out.println(isContain);// true

4、连接两个数组

int[] array1 = { 1, 2, 3, 4, 5 };int[] array2 = { 6, 7, 8, 9, 10 };// Apache Commons Lang libraryint[] combinedIntArray = ArrayUtils.addAll(array1, array2);

5、在一行声明一个数组

method(new String[]{"a", "b", "c", "d", "e"});

6、数组倒置

int[] intArray = { 1, 2, 3, 4, 5 };// Apache Commons Lang libraryArrayUtils.reverse(intArray);System.out.println(Arrays.toString(intArray));//[5, 4, 3, 2, 1]

7、删除某个元素

int[] intArray = { 1, 2, 3, 4, 5 };int[] removed = ArrayUtils.removeElement(intArray, 3);//create a new arraySystem.out.println(Arrays.toString(removed));

8、转化为set

Set<String> set = new HashSet<String>(Arrays.asList(new String[]{"a", "b", "c", "d", "e"}));System.out.println(set);//[d, e, b, c, a]

9、将Array List转化为Array

String[] stringArray = { "a", "b", "c", "d", "e" };ArrayList<String> arrayList = new ArrayList<String>(Arrays.asList(stringArray));String[] stringArr = new String[arrayList.size()];arrayList.toArray(stringArr);

10、将数组元素组成一个字符串

// Apache common langString j = StringUtils.join(new String[] { "a", "b", "c" }, ", ");System.out.println(j); //a, b, c