Java中的DoubleBuffer slice()方法及示例

Java.nio.DoubleBuffer类的slice()方法用于创建一个新的双缓冲区，其内容是给定缓冲区内容的共享子序列。

新缓冲区的内容将从该缓冲区的当前位置开始。对此缓冲区内容的更改将在新缓冲区中可见，反之亦然。两个缓冲区的位置、限制和标记值将是独立的。

新缓冲区的位置将为零，其容量和限制将是此缓冲区中剩余的双精度数，其标记将未定义。当且仅当此缓冲区是直接的时，新缓冲区将是直接的，并且当且仅当此缓冲区是只读的时，它将是只读的。

句法：

public abstract DoubleBuffer slice()

返回值：此方法返回新的双缓冲区。

以下是说明 slice() 方法的示例：

示例 1：

Java

// Java program to demonstrate
// slice() method
 
import java.nio.*;
import java.util.*;
 
public class GFG {
 
    public static void main(String[] args)
    {
 
        // Declaring the capacity of the DoubleBuffer
        int capacity = 10;
 
        // Creating the DoubleBuffer
        try {
 
            // creating object of Doublebuffer
            // and allocating size capacity
            DoubleBuffer fb1 = DoubleBuffer.allocate(capacity);
 
            // putting the value in Doublebuffer
            fb1.put(8.56F);
            fb1.put(9.61F);
 
            // print the DoubleBuffer
            System.out.println("Original DoubleBuffer: "
                               + Arrays.toString(fb1.array()));
 
            // print the DoubleBuffer position
            System.out.println("\nposition:  " + fb1.position());
 
            // print the DoubleBuffer capacity
            System.out.println("\ncapacity:  " + fb1.capacity());
 
            // Creating a shared subsequence buffer of given DoubleBuffer
            // using slice() method
            DoubleBuffer fb2 = fb1.slice();
 
            // print the shared subsequence buffer
            System.out.println("\nshared subsequence DoubleBuffer: "
                               + Arrays.toString(fb2.array()));
 
            // print the DoubleBuffer position
            System.out.println("\nposition:  " + fb2.position());
 
            // print the DoubleBuffer capacity
            System.out.println("\ncapacity:  " + fb2.capacity());
        }
 
        catch (IllegalArgumentException e) {
 
            System.out.println("IllegalArgumentException catched");
        }
 
        catch (ReadOnlyBufferException e) {
 
            System.out.println("ReadOnlyBufferException catched");
        }
    }
}

输出

Original DoubleBuffer: [8.5600004196167, 9.609999656677246, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0]

position:  2

capacity:  10

shared subsequence DoubleBuffer: [8.5600004196167, 9.609999656677246, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0]

position:  0

capacity:  8

示例 2：

Java

// Java program to demonstrate
// slice() method
 
import java.nio.*;
import java.util.*;
 
public class GFG {
 
    public static void main(String[] args)
    {
 
        // Declaring the capacity of the DoubleBuffer
        int capacity = 10;
 
        // Creating the DoubleBuffer
        try {
 
            // creating object of Doublebuffer
            // and allocating size capacity
            DoubleBuffer fb1 = DoubleBuffer.allocate(capacity);
 
            // putting the value in Doublebuffer
            fb1.put(8.56F);
            fb1.put(9.61F);
            fb1.put(0.56F);
            fb1.put(3.61F);
 
            // print the DoubleBuffer
            System.out.println("Original DoubleBuffer: "
                               + Arrays.toString(fb1.array()));
 
            // print the DoubleBuffer position
            System.out.println("\nposition:  " + fb1.position());
 
            // print the DoubleBuffer capacity
            System.out.println("\ncapacity:  " + fb1.capacity());
 
            // Creating a shared subsequence buffer of given DoubleBuffer
            // using slice() method
            DoubleBuffer fb2 = fb1.slice();
            fb2.put(2.34F);
            fb2.put(6.34F);
 
            // print the shared subsequence buffer
            System.out.println("\nshared subsequence DoubleBuffer: "
                               + Arrays.toString(fb2.array()));
 
            // print the DoubleBuffer position
            System.out.println("\nposition:  " + fb2.position());
 
            // print the DoubleBuffer capacity
            System.out.println("\ncapacity:  " + fb2.capacity());
        }
 
        catch (IllegalArgumentException e) {
 
            System.out.println("IllegalArgumentException catched");
        }
 
        catch (ReadOnlyBufferException e) {
 
            System.out.println("ReadOnlyBufferException catched");
        }
    }
}

输出

Original DoubleBuffer: [8.5600004196167, 9.609999656677246, 0.5600000023841858, 3.609999895095825, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0]

position:  4

capacity:  10

shared subsequence DoubleBuffer: [8.5600004196167, 9.609999656677246, 0.5600000023841858, 3.609999895095825, 2.3399999141693115, 6.340000152587891, 0.0, 0.0, 0.0, 0.0]

position:  2

capacity:  6