In Java, one of the convenient ways to determine the length or size of an array is by using its length property. It counts the number of elements stored in an array and returns the count. Finding the length of an array is one of the common yet crucial operation as it is used to find the number of elements of an array, append new elements into it and retrieve stored items. This article aims to explain the various ways to get the length or size of an array.
Java Program to determine the length or size of an Array
以下示例将帮助我们了解如何找到数组的大小。
Example 1
的中文翻译为：示例 1
The following example illustrates the use of length property with an array of type integer.
import java.util.*;
public class Example1 {
public static void main(String[] args) {
int[] aray = new int[5]; // declaring array of size 5
// initializing the array
aray[0] = 11;
aray[1] = 21;
aray[2] = 13;
aray[3] = 23;
aray[4] = 30;
// printing the elements of array
System.out.println("Elements of the given array: ");
for(int elm : aray) {
System.out.print(elm + " ");
}
System.out.println();
// printing the length of array
System.out.println("Length of the given array: " + aray.length);
}
}
Output
Elements of the given array: 11 21 13 23 30 Length of the given array: 5
在上面的代码中，我们声明了一个大小为5的数组，这意味着它可以存储最多5个元素。然后，使用for-each循环，我们检索了所有的元素，并且借助length属性确定了给定数组的大小。
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Example 2
的中文翻译为：示例2
In this example, we will declare and initialize a String array. Then, using a for-each loop, we will print its element. In the end, with the help length property, we determine the size of given array.
import java.util.*;
public class Example2 {
public static void main(String[] args) {
// declaration and initialization of the array
String[] aray = { "Tutorix", "Tutorials", "Point", "Simply", "Easy",
"Learning"
};
// printing the elements of array
System.out.println("Elements of the given array: ");
for(String elm : aray) {
System.out.print(elm + " ");
}
System.out.println();
// printing the length of array
System.out.println("Length of the given array: " + aray.length);
}
}
Output
Elements of the given array: Tutorix Tutorials Point Simply Easy Learning Length of the given array: 6
Example 3
This is another example where we will find the size of an array without using any in-built property or method of Java.
方法
声明并初始化两个数组。一个是字符串数组，另一个是整数数组
然后，定义两个整数类型的计数变量来存储两个数组的元素数量。
Now, use the for-each loop to iterate and increment the counter variable by one with each iteration.
最后，打印结果并退出。
import java.util.*;
public class Example3 {
public static void main(String[] args) {
// declaration and initialization of the arrays
String[] aray1 = { "Tutorix", "Tutorials", "Point", "Simply", "Easy",
"Learning"
};
int[] aray2 = {58, 66, 74, 55, 62};
// initial counter variable to store the count of elements
int countr1 = 0;
int countr2 = 0;
// printing the length of both arrays
for(String elm : aray1) {
countr1++;
}
for(int elm : aray2) {
countr2++;
}
System.out.println("Length of the String array: " + countr1);
System.out.println("Length of the integer array: " + countr2);
}
}
Output
Length of the String array: 6 Length of the integer array: 5
结论
在本文中，我们通过示例程序学习了使用length属性来确定给定数组的大小。此外，我们还讨论了一种在不使用任何内置方法和属性的情况下找到数组长度的方法。
