1. 声明一个数组
Java代码
1.String[] aArray =newString[5];
2.String[] bArray = {"a","b","c","d","e"};
3.String[] cArray =newString[]{"a","b","c","d","e"};
2. 输出一个数组
Java代码
1.int[] intArray = {1,2,3,4,5};
2.String intArrayString = Arrays.toString(intArray);
3.
4.// print directly will print reference value
5.System.out.println(intArray);
6.// [I@7150bd4d
7.
8.System.out.println(intArrayString);
9.// [1, 2, 3, 4, 5]
3. 从一个数组创建数组列表
Java代码
1.String[] stringArray = {"a","b","c","d","e"};
2.ArrayList arrayList =newArrayList(Arrays.asList(stringArray));
3.System.out.println(arrayList);
4.// [a, b, c, d, e]
4. 检查一个数组是否包含某个值
Java代码
1.String[] stringArray = {"a","b","c","d","e"};
2.booleanb = Arrays.asList(stringArray).contains("a");
3.System.out.println(b);
4.// true
5. 连接两个数组
Java代码
1.int[] intArray = {1,2,3,4,5};
2.int[] intArray2 = {6,7,8,9,10};
3.// Apache Commons Lang library
4.int[] combinedIntArray = ArrayUtils.addAll(intArray, intArray2);
6. 声明一个内联数组（Array inline）
Java代码
1.method(newString[]{"a","b","c","d","e"});
7. 把提供的数组元素放入一个字符串
Java代码
1.// containing the provided list of elements
2.// Apache common lang
3.String j = StringUtils.join(newString[] {"a","b","c"},", ");
4.System.out.println(j);
5.// a, b, c
8. 将一个数组列表转换为数组
Java代码
1.String[] stringArray = {"a","b","c","d","e"};
2.ArrayList arrayList =newArrayList(Arrays.asList(stringArray));
3.String[] stringArr =newString[arrayList.size()];
4.arrayList.toArray(stringArr);
5.for(String s : stringArr)
6.System.out.println(s);
9. 将一个数组转换为集（set）
Java代码
1.Set set =newHashSet(Arrays.asList(stringArray));
2.System.out.println(set);
3.//[d, e, b, c, a]
10. 逆向一个数组
Java代码
1.int[] intArray = {1,2,3,4,5};
2.ArrayUtils.reverse(intArray);
3.System.out.println(Arrays.toString(intArray));
4.//[5, 4, 3, 2, 1]
11. 移除数组中的元素
Java代码
1.int[] intArray = {1,2,3,4,5};
2.int[] removed = ArrayUtils.removeElement(intArray,3);//create a new array
3.System.out.println(Arrays.toString(removed));
12. 将整数转换为字节数组
Java代码
1.byte[] bytes = ByteBuffer.allocate(4).putInt(8).array();
2.
3.for(bytet : bytes) {
4.System.out.format("0x%x ", t);
5.}
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