Java《数组》

数组的定义：
     数据类型 数组名[] = new 数据类型[大小];
     int a[] = new int[5];

声明数组：
     数据类型 数组名[]; 或 数据类型[] 数组名;
     int a[]; 或 int[] a;

与C语言定义初始化数组相同：
     int a[] = {1, 2, 3, 4, 5, 6, 7, 8, 9};

代码示例：

public class Demo1 {    public static void main(String[] args) {        float arr[] = new float[6];        arr[0] = 3;        arr[1] = 1;        arr[2] = 5;        arr[3] = 3.4f;        arr[4] = 2;        arr[5] = 8;        float total  = 0;        for(int i = 0; i < arr.length; ++i) {            total += arr[i];        }        System.out.println("total="+total);        // 计算数组大小，结果为:6        System.out.println(arr.length);    }}

对象数组代码示例：

import java.io.*;public class Demo2 {    public static void main(String[] args) throws Exception {        // 定义一个对象数组        Dog dogs[] = new Dog[4];        // 从控制台输入初始化信息        InputStreamReader isr = new InputStreamReader(System.in);        BufferedReader br = new BufferedReader(isr);        float totalWeight = 0;        for(int i = 0; i < dogs.length; ++i) {            dogs[i] = new Dog();            System.out.println("请输入狗名");            String name = br.readLine();            dogs[i].setName(name);            System.out.println("请输入狗的体重");            String s_weight = br.readLine();            float weight = Float.parseFloat(s_weight);            dogs[i].setWeight(weight);            totalWeight += dogs[i].getWeight();        }        System.out.println("平均体重:"+totalWeight/dogs.length);    }}class Dog {    private String name;    private float weight;    public String getName() {        return name;    }    public void setName(String name) {        this.name = name;    }    public float getWeight() {        return weight;    }    public void setWeight(float weight) {        this.weight = weight;    }}