1. 输出内容最常见的方式
- // List类型的列表
- List list = new ArrayList();
- list.add("First");
- list.add("Second");
- list.add("Third");
- list.add("Fourth");
- System.out.println(list);
输出:
[First, Second, Third, Fourth]
- // String数组
- "code" class="java">String[] array = new String[] { "First", "Second", "Third", "Fourth" };
- System.out.println(array.toString());
输出:
[Ljava.lang.String;@12dacd1
2. 使用Array类输出数组内容
- // String数组
- String[] array = new String[] { "First", "Second", "Third", "Fourth" };
- System.out.println(Arrays.toString(array));
输出:
[First, Second, Third, Fourth]
3. 输出数组的数组
可以使用Arrays.deepToString()方法。- String[] arr1 = new String[] { "Fifth", "Sixth" };
- String[] arr2 = new String[] { "Seventh", "Eight" };
- // 数组的数组
- String[][] arrayOfArray = new String[][] { arr1, arr2 };
- // 比较下面的输出
- System.out.println(arrayOfArray);
- System.out.println(Arrays.toString(arrayOfArray));
- System.out.println(Arrays.deepToString(arrayOfArray));
输出:
[[Ljava.lang.String;@1ad086a
[[Ljava.lang.String;@10385c1, [Ljava.lang.String;@42719c]
[[Fifth, Sixth], [Seventh, Eighth]]
再看下面的完整例子:
- import java.util.ArrayList;
- import java.util.Arrays;
- import java.util.List;
- public class PrintArray {
- public static void main(String[] args) {
- List list = new ArrayList();
- list.add("First");
- list.add("Second");
- list.add("Third");
- list.add("Fourth");
- System.out.println(list);
- String[] array = new String[] { "First", "Second", "Third", "Fourth" };
- System.out.println(array.toString());
- System.out.println(Arrays.toString(array));
- String[] arr1 = new String[] { "Fifth", "Sixth" };
- String[] arr2 = new String[] { "Seventh", "Eigth" };
- String[][] arrayOfArray = new String[][] { arr1, arr2 };
- System.out.println(arrayOfArray);
- System.out.println(Arrays.toString(arrayOfArray));
- System.out.println(Arrays.deepToString(arrayOfArray));
- }
- }
输出:
[First, Second, Third, Fourth]
[Ljava.lang.String;@12dacd1
[First, Second, Third, Fourth]
[[Ljava.lang.String;@1ad086a
[[Ljava.lang.String;@10385c1, [Ljava.lang.String;@42719c]
[[Fifth, Sixth], [Seventh, Eigth]]