Java Vector trimToSize()
Java Vector类的
trimToSize()方法用于将Vector 的容量修整为Vector 的目前的规模。应用程序可以使用此操作来最小化向量的存储。
语法
以下是
trimToSize()方法的声明:
参数
此方法不接受任何参数。
返回
trimToSize()方法不会返回任何内容。
异常
NA
兼容版本
Java 1.2及更高版本
示例1
import java.util.*;
public class VectorTrimToSizeExample1 {
public static void main(String arg[]) {
//Create an empty vector
Vector<Integer> vec = new Vector<>(8);
//Add elements in the vector
vec.add(1);
vec.add(2);
vec.add(3);
vec.add(4);
vec.add(5);
//Trims the size to the number of elements
vec.trimToSize();
System.out.println("The elements of a vector are:");
//Displaying all the elements
for (Integer number : vec) {
System.out.println("Number = " + number);
}
}
}
输出:
The elements of a vector are:
Number = 1
Number = 2
Number = 3
Number = 4
Number = 5
示例2
import java.util.*;
public class VectorTrimToSizeExample2 {
public static void main(String arg[]) {
//Create an empty vector
Vector < String > colors = new Vector < String > (9);
//Add elements in the vector
colors.add("White");
colors.add("Green");
colors.add("Black");
colors.add("Pink");
//Prints size of the vector
System.out.println("The initial size of the vector: "+colors.capacity());
//Trims the size to the number of elements
colors.trimToSize();
System.out.println("The elements of a vector are:");
//Displaying all the elements
for (String strcolor : colors) {
System.out.println(" " + strcolor);
}
//Prints size of the vector
System.out.println("Size of the vector after trimToSize(): " +colors.capacity());
}
}
输出:
The initial size of the vector: 9
The elements of a vector are:
White
Green
Black
Pink
Size of the vector after trimToSize(): 4
