极客教程Java 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一个共享子序列。
新缓冲区的内容将从这个缓冲区的当前位置开始。这个缓冲区的内容的变化将在新的缓冲区中可见，反之亦然。两个缓冲区的位置、极限和标记值将是独立的。
新缓冲区的位置将是零，它的容量和极限将是这个缓冲区中剩余的双倍数，而它的标记将是未定义的。新的缓冲区将是直接的，当且仅当这个缓冲区是直接的，它将是只读的，当且仅当这个缓冲区是只读的。
语法
public abstract DoubleBuffer slice()
返回值： 该方法返回 新的DoubleBuffer 。
下面是说明slice()方法的例子。
例子 1 :
// 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
例子 2 :
// 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