Java中的 ShortBuffer clear() 方法及示例
Java.nio.ShortBuffer类的clear()方法用于清除这个缓冲区。在完成更改后清除此缓冲区时:
- 当前位置设置为零
- 此 ShortBuffer 实例的限制设置为容量
- 此 ShortBuffer 实例的标记(如果有)将被丢弃。
句法:
public final ShortBuffer clear()
返回值:此方法在清除其中的所有数据后返回此ShortBuffer实例。
以下是说明 clear() 方法的示例:
示例 1:
// Java program to demonstrate
// clear() method
import java.nio.*;
import java.util.*;
public class GFG {
public static void main(String[] args)
{
try {
short[] darr = { 2, 3, 4, 6 };
// creating object of ShortBuffer
// and allocating size capacity
ShortBuffer db
= ShortBuffer.wrap(darr);
// try to set the position at index 2
db.position(2);
// Set this buffer mark position
// using mark() method
db.mark();
// try to set the position at index 4
db.position(4);
// display position
System.out.println("position before reset: "
+ db.position());
// try to call clear() to restore
// to the position at index 0
// by discarding the mark
db.clear();
// display position
System.out.println("position after reset: "
+ db.position());
}
catch (InvalidMarkException e) {
System.out.println("new position is less than "
+ "the position we "
+ "marked before ");
System.out.println("Exception throws: " + e);
}
}
}
输出:
position before reset: 4
position after reset: 0
示例 2:
// Java program to demonstrate
// clear() method
import java.nio.*;
import java.util.*;
public class GFG {
public static void main(String[] args)
{
short[] carr = { 2, 10, 13, 23 };
// creating object of ShortBuffer
// and allocating size capacity
ShortBuffer db = ShortBuffer.wrap(carr);
// try to set the position at index 3
db.position(3);
// display position
System.out.println("position before clear: "
+ db.position());
// try to call clear() to restore
// to the position at index 0
// by discarding the mark
db.clear();
// display position
System.out.println("position after clear: "
+ db.position());
}
}
输出:
position before clear: 3
position after clear: 0
参考: https://docs.oracle.com/javase/9/docs/api/ Java/nio/ShortBuffer.html#clear–