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This article mainly explains "how to use Java array syntax". Interested friends may wish to have a look at it. The method introduced in this paper is simple, fast and practical. Now let the editor take you to learn how to use Java array syntax.

1. The concept of array.

An array is a container that stores data of a fixed length, and the data type for storing multiple data should be the same.

2. Array definition format

First: data type [] array name

Example:

```java

Int [] arr

Double [] arr

Char [] arr

`

Second: data type array name []

Example:

```java

Int arr []

Double arr []

Char arr []

`

3. Array dynamic initialization

(1) what is dynamic initialization?

Array dynamic initialization means that only the length of the array is given and the default initialization value is given by the system.

(2) dynamic initialization format:

```java

Data type [] array name = new data type [array length]

```java

Int [] arr = new int [3]

`

(3) detailed explanation of dynamic initialization format

A, left side of the equal sign:

-int: data type of the array

-[]: indicates that this is an array

-arr: the name that represents the array

B, to the right of the equal sign:

-new: open up memory space for arrays

-int: data type of the array

-[]: indicates that this is an array

-5: represents the length of the array

4. Array element access (mainly application-based)

(1) what is an index

Each element stored in the array automatically has a number, starting with 0. This automatic numbering is called an array index (index), and the elements in the array can be accessed through the array's index.

(2) access array element format

```java

Array name [index]

`

(3) sample code

```java

Public class ArrayDemo {

Public static void main (String [] args) {

Int [] arr = new int [3]

/ / output array name

System.out.println (arr); / / [I@880ec60

/ / output elements in the array

System.out.println (arr [0])

System.out.println (arr [1])

System.out.println (arr [2])

}

}

`

5. Memory allocation

(1) Overview of memory

Memory is an important original in the computer, temporary storage area, the function is to run the program. The programs we write are stored on the hard disk, and the programs on the hard disk will not run. It must be put in memory to run, and the memory will be emptied after running. In order to run the program, the Java virtual machine must allocate and manage the memory space.

(2) memory allocation in Java

At present, we only need to remember two pieces of memory, namely, stack memory and heap memory

A, register: for CPU use, has nothing to do with our development.

B, local method stack: JVM is used when using the functions of the operating system, which has nothing to do with our development.

C, method area: store class files that can be run.

D, heap memory: store objects or arrays, created by new, are stored in heap memory.

E, method stack: the memory used when the method is running, such as the main method, is executed in the method stack.

6. Array static initialization

(1) what is static initialization?

When creating an array, the element is determined directly.

(2) static initialization format

-full version format

```java

Data type [] array name = new data type [] {element 1, element 2.}

`

-simplified format

```java

Data type [] array name = {element 1, element 2.}

`

(3) sample code

```java

Public class ArrayDemo {

Public static void main (String [] args) {

/ / define an array

Int [] arr = {1,2,3}

/ / output array name

System.out.println (arr)

/ / output elements in the array

System.out.println (arr [0])

System.out.println (arr [1])

System.out.println (arr [2])

}

}

`

At this point, I believe you have a deeper understanding of "how to use Java array syntax". You might as well do it in practice. Here is the website, more related content can enter the relevant channels to inquire, follow us, continue to learn!

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