关于Java数组的12个最佳方法

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下面是stackoverflow中关于数组方法的相关问题中，获得最多票数的12个数组操作方法。

1. 声明一个数组

  1. String[] aArray = new String[5];
  2. String[] bArray = {"a","b","c", "d", "e"};
  3. String[] cArray = new String[]{"a","b","c","d","e"};

2. 输出一个数组

  1. int[] intArray = { 1, 2, 3, 4, 5 };
  2. String intArrayString = Arrays.toString(intArray);
  4. // print directly will print reference value
  5. System.out.println(intArray);
  6. // [I@7150bd4d
  8. System.out.println(intArrayString);
  9. // [1, 2, 3, 4, 5]

3. 从一个数组创建数组列表

  1. String[] stringArray = { "a", "b", "c", "d", "e" };
  2. ArrayList<String> arrayList = new ArrayList<String>(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

  1. String[] stringArray = { "a", "b", "c", "d", "e" };
  2. boolean b = Arrays.asList(stringArray).contains("a");
  3. System.out.println(b);
  4. // true

5. 连接两个数组

  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

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

7. 把提供的数组元素放入一个字符串

  1. // containing the provided list of elements
  2. // Apache common lang
  3. String j = StringUtils.join(new String[] { "a", "b", "c" }, ", ");
  4. System.out.println(j);
  5. // a, b, c

8. 将一个数据列表转换为数组

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

  1. Set<String> set = new HashSet<String>(Arrays.asList(stringArray));
  2. System.out.println(set);
  3. //[d, e, b, c, a]

10. 逆向一个数组

  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

  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

  1. byte[] bytes = ByteBuffer.allocate(4).putInt(8).array();
  3. for (byte t : bytes) {
  4. System.out.format("0x%x ", t);
  5. }

Via programcreek

  1. da shang
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