Java 中的默认数组值
javajava programming java 8更新于 2024/6/28 16:31:00
Java 提供了一种数据结构，即数组，它存储了相同类型元素的固定大小的顺序集合。数组用于存储数据集合，但将数组视为相同类型变量的集合通常更有用。当创建数组而未为其分配任何元素时，编译器会为它们分配默认值。以下是示例:
- Boolean - false
- int - 0
- double - 0.0
- Object - null
示例
public class Tester {
public static void main(String[] args) {
System.out.print("Default values (String array):");
String strings[] = new String[5];
for (String s : strings) {
System.out.print(s + " ");
}
System.out.println();
System.out.print("Default values (int array):");
int numbers[] = new int[5];
for (int val : numbers) {
System.out.print(val + " ");
}
System.out.println();
System.out.print("Default values (double array):");
double doubles[] = new double[5];
for (double val : doubles) {
System.out.print(val + " ");
}
System.out.println();
System.out.print("Default values (boolean array):");
boolean booleans[] = new boolean[5];
for (boolean val : booleans) {
System.out.print(val + " ");
}
System.out.println();
System.out.print("Default values (Object array):");
Tester testers[] = new Tester[5];
for (Tester val : testers) {
System.out.print(val + " ");
}
}
}
输出
Default values (String array):null null null null null Default values (int array):0 0 0 0 0 Default values (double array):0.0 0.0 0.0 0.0 0.0 Default values (boolean array):false false false false false Default values (Object array):null null null null null
