直接拿来用！超实用的Java数组技巧攻略

直接拿来用！超实用的Java数组技巧攻略

本文分享了关于Java数组最顶级的11大方法，帮助你解决工作流程问题，无论是运用在团队环境或是在私人项目中，你都可以直接拿来用！

0. 声明一个数组（Declare an array）

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1. String[] aArray = new String[5];
2. String[] bArray = {"a","b","c", "d", "e"};
3. String[] cArray = new String[]{"a","b","c","d","e"};
   1. 在Java中输出一个数组（Print an array in Java）

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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]
   2. 从数组中创建数组列表（Create an ArrayList from an array）

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1. String[] stringArray = { "a", "b", "c", "d", "e" };
2. ArrayList arrayList = new ArrayList(Arrays.asList(stringArray));
3. System.out.println(arrayList);
4. // [a, b, c, d, e]
   3. 检查数组中是否包含特定值（Check if an array contains a certain value）

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1. String[] stringArray = { "a", "b", "c", "d", "e" };
2. boolean b = Arrays.asList(stringArray).contains("a");
3. System.out.println(b);
4. // true
   4. 连接两个数组（ Concatenate two arrays）

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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);
   5. 声明一个数组内链（Declare an array inline ）

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

6. 将数组元素加入到一个独立的字符串中（Joins the elements of the provided array into a single String）

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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
   7. 将数组列表转换成一个数组 （Covnert an ArrayList to an array）

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1. String[] stringArray = { "a", "b", "c", "d", "e" };
2. ArrayList arrayList = new ArrayList(Arrays.asList(stringArray));
3. String[] stringArr = new String[arrayList.size()];
4. arrayList.toArray(stringArr);
5. for (String s : stringArr)
6. System.out.println(s);
   8. 将数组转换成一个集合（Convert an array to a set）

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1. Set set = new HashSet(Arrays.asList(stringArray));
2. System.out.println(set);
3. //[d, e, b, c, a]
   9. 反向数组（Reverse an array）

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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]
   10. 删除数组元素（Remove element of an array）

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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));
   One more – convert int to byte array

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1. byte[] bytes = ByteBuffer.allocate(4).putInt(8).array();
3. for (byte t : bytes) {
4. System.out.format("0x%x ", t);
5. }
   来源： [http://www.csdn.net/article/2013-09-16/2816947-methods-for-java-arrays](http://www.csdn.net/article/2013-09-16/2816947-methods-for-java-arrays)

Top 10 Methods for Java Arrays

The following are top 10 methods for Java Array. They are the most voted questions from stackoverflow.

0. Declare an array String[] aArray = new String[5];String[] bArray = {"a","b","c", "d", "e"};String[] cArray = new String[]{"a","b","c","d","e"};

1. Print an array in Java

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

2. Create an ArrayList from an array

String[] stringArray = { "a", "b", "c", "d", "e" };ArrayList arrayList = new ArrayList(Arrays.asList(stringArray));System.out.println(arrayList);// [a, b, c, d, e]

3. Check if an array contains a certain value

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

4. Concatenate two arrays

int[] intArray = { 1, 2, 3, 4, 5 };int[] intArray2 = { 6, 7, 8, 9, 10 };// Apache Commons Lang libraryint[] combinedIntArray = ArrayUtils.addAll(intArray, intArray2);

5. Declare an array inline

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

6. Joins the elements of the provided array into a single String

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

7. Covnert an ArrayList to an array

String[] stringArray = { "a", "b", "c", "d", "e" };ArrayList arrayList = new ArrayList(Arrays.asList(stringArray));String[] stringArr = new String[arrayList.size()];arrayList.toArray(stringArr);for (String s : stringArr) System.out.println(s);

8. Convert an array to a set

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

9. Reverse an array

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

10. Remove element of an array

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

One more – convert int to byte array

byte[] bytes = ByteBuffer.allocate(4).putInt(8).array(); for (byte t : bytes) { System.out.format("0x%x ", t);} 来源： [http://www.programcreek.com/2013/09/top-10-methods-for-java-arrays/](http://www.programcreek.com/2013/09/top-10-methods-for-java-arrays/)