How to use arrays in Java?

Use a simple array

(1)Create a class named T04 and declare two variables array1 and array2 in the main() method

They are arrays of type int[] .

(2) Use curly brackets {} to initialize array1 to 8 prime numbers: 2, 3, 5, 7, 11, 13, 17, 19.

(3) Display the contents of array1.

(4) Assign array2 variable equal to array1, modify the even index element in array2 to make it equal to the index value (such as array[0]=0, array[2]=2). Print out array1. **Thinking: What is the relationship between array1 and array2?
Extension: Modify the question to realize the copying of array1 array by array2

public class T04 {
    public static void main(String[] args) {
        int[] array1,array2;
        array1=new int[]{2,3,5,7,11,13,17,19};
        for(int i=0;i< array1.length;i++){
            System.out.print(array1[i]+"\t");
        }　　　　　//赋值array1变量等于array2　　　　 //不能称作数组的复制
        array2=array1;
        for(int i=0;i< array1.length;i++){
            if(i%2==0){
                array2[i]=i;
            }
        }
        System.out.println();
        System.out.println("******************************************");
        for(int i=0;i< array1.length;i++){
            System.out.print(array1[i]+"\t");
        }
    }
}

(1) The addresses of array1 and array2 The values ​​are the same, and they all point to the only array entity in the heap space

(2)

 for(int i=0;i< array1.length;i++){
            array2[i]=array1[i];
        }

Method 2

int i=0;
        int j=0;
        for(i=0,j= arr.length-1;i<j;i++,j--){
            int a=arr[i];
            arr[i]=arr[j];
            arr[j]=a;
        }

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