声明对象引用数组：

class Animal {}

class Horse extends Animal {
    public static void main(String[] args) {

        /*
         * Array of Animal can hold Animal and Horse (all subtypes of Animal allowed)
         */
        Animal[] a1 = new Animal[10];
        a1[0] = new Animal();
        a1[1] = new Horse();

        /*
         * Array of Animal can hold Animal and Horse and all subtype of Horse
         */
        Animal[] a2 = new Horse[10];
        a2[0] = new Animal();
        a2[1] = new Horse();

        /*
         * Array of Horse can hold only Horse and its subtype (if any) and not
           allowed supertype of Horse nor other subtype of Animal.
         */
        Horse[] h1 = new Horse[10];
        h1[0] = new Animal(); // Not allowed
        h1[1] = new Horse();

        /*
         * This can not be declared.
         */
        Horse[] h2 = new Animal[10]; // Not allowed
    }
}

Type[] variableName = new Type[capacity];

Type[] variableName = {comma-delimited values};



Type variableName[] = new Type[capacity]; 

Type variableName[] = {comma-delimited values};

也是有效的，但我更喜欢在类型后面加括号，因为更容易看出变量的类型实际上是一个数组。

如果要使用反射创建阵列，可以执行以下操作：

 int size = 3;
 int[] intArray = (int[]) Array.newInstance(int.class, size ); 

声明对象引用数组：

class Animal {}

class Horse extends Animal {
    public static void main(String[] args) {

        /*
         * Array of Animal can hold Animal and Horse (all subtypes of Animal allowed)
         */
        Animal[] a1 = new Animal[10];
        a1[0] = new Animal();
        a1[1] = new Horse();

        /*
         * Array of Animal can hold Animal and Horse and all subtype of Horse
         */
        Animal[] a2 = new Horse[10];
        a2[0] = new Animal();
        a2[1] = new Horse();

        /*
         * Array of Horse can hold only Horse and its subtype (if any) and not
           allowed supertype of Horse nor other subtype of Animal.
         */
        Horse[] h1 = new Horse[10];
        h1[0] = new Animal(); // Not allowed
        h1[1] = new Horse();

        /*
         * This can not be declared.
         */
        Horse[] h2 = new Animal[10]; // Not allowed
    }
}

或者，

// Either method works
String arrayName[] = new String[10];
String[] arrayName = new String[10];

它声明了一个名为arrayName的数组，大小为10（您可以使用元素0到9）。

声明数组：int[]arr；

初始化数组：int[]arr=new int[10]；10表示数组中允许的元素数

声明多维数组：int[][]arr；

初始化多维数组：int[][]arr=new int[10][17]；10行17列和170个元素，因为10乘以17等于170。

初始化数组意味着指定数组的大小。