java各种数据类型的数组元素的默认值
public class DataTypeDefaultValue {public static void main(String[] args) {// string类型数组的默认值null
// 对于引用类型的属性的默认值是null,如String类型
System.out.println("查看String类型中数组的默认值:");
String[] str = new String[4];
str[0] = "aa";
str[1] = "bb";
str[2] = "cc";
for (int i = 0; i < 4; i++) {System.out.println(str[i]);}// 对于short,int,long,byte而言,创建数组的默认值是0
System.out.println("查看int类型数组的默认值:");
int[] score = new int[4];score[0] = 90;score[1] = 89;score[2] = 34;for (int i = 0; i < score.length; i++) {System.out.println(score[i]);}System.out.println("查看short类型数组的默认值:");
short[] score1 = new short[4];score1[0] = 90;for (int i = 0; i < score1.length; i++) {System.out.println(score1[i]);}System.out.println("查看long类型数组的默认值:");
long[] score2 = new long[4];score2[0] = 90;for (int i = 0; i < score2.length; i++) {System.out.println(score2[i]);}System.out.println("查看byte类型数组的默认值:");
byte[] score3 = new byte[4];score3[0] = 90;for (int i = 0; i < score3.length; i++) {System.out.println(score3[i]);}// 对于float double而言,默认值是0.0
System.out.println("查看float类型数组的默认值:");
float[] score4 = new float[4];score4[0] = 23;for (int i = 0; i < score4.length; i++) {System.out.println(score4[i]);}System.out.println("查看double类型数组的默认值:");
double[] score5 = new double[4];score5[0] = 45;for (int i = 0; i < score5.length; i++) {System.out.println(score5[i]);}// 对于char类型
// char类型数组的默认值是空格
System.out.println("查看char类型数组的默认值:");
char[] ch = new char[4];ch[0] = 'p';for (int i = 0; i < ch.length; i++) {System.out.println(ch[i]);}// 对于boolean类型的数组默认值
// boolean类型数组的默认值是false
System.out.println("查看boolean数组的默认值:");
boolean[] b = new boolean[4];b[0] = true;
for (int i = 0; i < b.length; i++) {System.out.println(b[i]);}/// 引用类型数组的默认值是null
class Person {
}System.out.println("查看引用类型的数组默认值:");
Person[] p = new Person[4];
for (int i = 0; i < p.length; i++) {System.out.println(p[i]);}}}
运行结果:
查看String类型中数组的默认值:aabbccnull查看int类型数组的默认值:9089340查看short类型数组的默认值:90000查看long类型数组的默认值:90000查看byte类型数组的默认值:90000查看float类型数组的默认值:23.00.00.00.0查看double类型数组的默认值:45.00.00.00.0查看char类型数组的默认值:p