Record the pits where an error occurs when an array is converted to a collection, and try to use an array of packaging types for conversion

When using array to collection, try to use the wrapper type array for conversion.

描述

• 使用Basic data types to create arrays的时候,When you want to turn it into a collection,It is equivalent to storing a reference in the collection.
• 使用The wrapper type creates an array,when converting it to a collection,A collection stores the values ​​in an array

How to convert an array to a collection

• Arrays.asList(数组); The converted collection cannot be modified such as adding or deleting,否则会报错
• Collections.addAll(arrayList, strArray)
• Arrays.stream(ints).boxed().collect(Collectors.toList());

代码示例

public class Test {
    
  public static void main(String[] args) {
    
    int[] arrInt = {
    1, 2, 3, 2, 2, 3, 2, 3};
    List<int[]> ints = Arrays.asList(arrInt);
    System.out.println(ints);

    Integer[] arrInteger = {
    1, 2, 3, 2, 2, 3, 2, 3};
    List<Integer> integers = Arrays.asList(arrInteger);
    System.out.println(integers);
  }
}

运行结果