Java中的LongBuffer duplicate()方法

Java.nio.LongBuffer类的duplicate()方法用于创建一个共享给定缓冲区内容的新Long 缓冲区。

句法：

public abstract LongBuffer duplicate()

返回值：此方法返回新的 Long 缓冲区，该缓冲区承载先前的 Long 缓冲区内容

以下是说明duplicate()方法的示例：

示例 1：使用直接 Longbuffer

// Java program to demonstrate
// duplicate() method
// Using direct Longbuffer
  
import java.nio.*;
import java.util.*;
  
public class GFG {
  
    public static void main(String[] args)
    {
  
        // Declaring the capacity of the LongBuffer
        int capacity = 10;
  
        // Creating the LongBuffer
        try {
  
            // creating object of Longbuffer
            // and allocating size capacity
            LongBuffer ib1 = LongBuffer.allocate(capacity);
  
            // putting the value in Longbuffer
            ib1.put(8);
            ib1.put(2, 9);
            ib1.rewind();
  
            // prLong the Original LongBuffer
            System.out.println("Original LongBuffer: "
                               + Arrays.toString(ib1.array()));
  
            // Creating a duplicate copy of LongBuffer
            // using duplicate() method
            LongBuffer ib2 = ib1.duplicate();
  
            // prLong the duplicate copy of LongBuffer
            System.out.println("Duplicate LongBuffer: "
                               + Arrays.toString(ib2.array()));
        }
  
        catch (IllegalArgumentException e) {
  
            System.out.println("IllegalArgumentException catched");
        }
  
        catch (ReadOnlyBufferException e) {
  
            System.out.println("ReadOnlyBufferException catched");
        }
    }
}

输出：

Original LongBuffer: [8, 0, 9, 0, 0, 0, 0, 0, 0, 0]
Duplicate LongBuffer: [8, 0, 9, 0, 0, 0, 0, 0, 0, 0]

示例 2：使用只读的Longbuffer

// Java program to demonstrate
// duplicate() method
// using read-onlyLongbuffer
  
import java.nio.*;
import java.util.*;
  
public class GFG {
  
    public static void main(String[] args)
    {
  
        // Declaring the capacity of the LongBuffer
        int capacity = 10;
  
        // Creating the LongBuffer
        try {
  
            // creating object of Longbuffer
            // and allocating size capacity
            LongBuffer ib1 = LongBuffer.allocate(capacity);
  
            // putting the value in Longbuffer
            ib1.put(8);
            ib1.put(2, 9);
            ib1.rewind();
  
            // prLong the Original LongBuffer
            System.out.println("Original LongBuffer:  "
                               + Arrays.toString(ib1.array()));
  
            // Creating a read-only copy of LongBuffer
            // using asReadOnlyBuffer() method
            LongBuffer readonly = ib1.asReadOnlyBuffer();
  
            // prLong the read-only copy of LongBuffer
            System.out.print("read-only LongBuffer:  ");
            while (readonly.hasRemaining())
                System.out.print(readonly.get() + ", ");
            System.out.println("");
  
            // Rewinding the readonly LongBuffer
            readonly.rewind();
  
            // Creating a duplicate copy of LongBuffer
            // using duplicate() method
            LongBuffer ib2 = readonly.duplicate();
  
            // prLong the duplicate copy of LongBuffer
            System.out.print("duplicate copy of read-only LongBuffer:  ");
  
            while (ib2.hasRemaining())
                System.out.print(ib2.get() + ", ");
            System.out.println("");
        }
  
        catch (IllegalArgumentException e) {
            System.out.println("IllegalArgumentException catched");
        }
  
        catch (ReadOnlyBufferException e) {
            System.out.println("ReadOnlyBufferException catched");
        }
    }
}

输出：

Original LongBuffer:  [8, 0, 9, 0, 0, 0, 0, 0, 0, 0]
read-only LongBuffer:  8, 0, 9, 0, 0, 0, 0, 0, 0, 0, 
duplicate copy of read-only LongBuffer:  8, 0, 9, 0, 0, 0, 0, 0, 0, 0,