Java LongBuffer asReadOnlyBuffer()用法及代码示例

java.nio.LongBuffer类的asReadOnlyBuffer()方法用于使用该缓冲区的内容创建一个新的只读Long缓冲区。新缓冲区是此缓冲区的副本。因此，对该缓冲区内容所做的更改将在新缓冲区中可见。

由于新缓冲区是只读缓冲区，因此不允许对其内容进行任何修改。这两个缓冲区的位置，限制和标记值将是独立的。新缓冲区的容量，限制，位置和标记值将与此缓冲区相同。如果此缓冲区本身是只读的，则此方法的行为与重复方法完全相同。

用法:

public abstract LongBuffer asReadOnlyBuffer()

返回值：此方法返回新的只读Long缓冲区，其内容与此缓冲区相同。

下面是说明asReadOnlyBuffer()方法的示例：

范例1：

// Java program to demonstrate 
// asReadOnlyBuffer() method 
  
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 ib = LongBuffer.allocate(capacity); 
  
            // putting the value in Longbuffer 
            ib.put(8); 
            ib.put(2, 9); 
            ib.rewind(); 
  
            // prLong the LongBuffer 
            System.out.println("Original LongBuffer:  "
                               + Arrays.toString(ib.array())); 
  
            // Creating a read-only copy of LongBuffer 
            // using asReadOnlyBuffer() method 
            LongBuffer LongBuffer = ib.asReadOnlyBuffer(); 
  
            // prLong the LongBuffer 
            System.out.print("\nReadOnlyBuffer LongBuffer: "); 
  
            while (LongBuffer.hasRemaining()) 
                System.out.print(LongBuffer.get() + ", "); 
        } 
  
        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]

ReadOnlyBuffer LongBuffer: 8, 0, 9, 0, 0, 0, 0, 0, 0, 0,

范例2：

// Java program to demonstrate 
// asReadOnlyBuffer() method 
  
import java.nio.*; 
import java.util.*; 
  
public class GFG { 
  
    public static void main(String[] args) throws Exception 
    { 
  
        // Declaring the capacity of the ib 
        int capacity1 = 10; 
  
        // Declaring the capacity of the ib1 
        int capacity2 = 5; 
  
        // Creating the LongBuffer 
        try { 
            // creating object of Longbuffer ib 
            // and allocating size capacity 
            LongBuffer ib = LongBuffer.allocate(capacity1); 
  
            // putting the value in ib 
            ib.put(8); 
            ib.put(2, 9); 
            ib.rewind(); 
  
            // prLong the LongBuffer 
            System.out.println("LongBuffer ib: "
                               + Arrays.toString(ib.array())); 
  
            // ib1 
            // creating object of Longbuffer ib1 
            // and allocating size capacity 
            LongBuffer ib1 = LongBuffer.allocate(capacity2); 
  
            // putting the value in ib1 
            ib1.put(1, 4); 
            ib1.put(2, 6); 
            ib1.rewind(); 
  
            // prLong the LongBuffer 
            System.out.println("\nLongBuffer ib1:  "
                               + Arrays.toString(ib1.array())); 
  
            // Creating a read-only copy of LongBuffer 
            // using asReadOnlyBuffer() method 
            LongBuffer readOnlyib = ib.asReadOnlyBuffer(); 
  
            // prLong the LongBuffer 
            System.out.print("\nReadOnlyBuffer LongBuffer: "); 
  
            while (readOnlyib.hasRemaining()) 
                System.out.print(readOnlyib.get() + ", "); 
  
            // try to change readOnlyib 
            System.out.println("\n\nTrying to get the array"
                               + " from ReadOnlyib for editing"); 
        } 
  
        catch (IllegalArgumentException e) { 
            System.out.println("IllegalArgumentException catched"); 
        } 
  
        catch (ReadOnlyBufferException e) { 
            System.out.println("Exception thrown: " + e); 
        } 
    } 
}

输出：

LongBuffer ib: [8, 0, 9, 0, 0, 0, 0, 0, 0, 0]

LongBuffer ib1:  [0, 4, 6, 0, 0]

ReadOnlyBuffer LongBuffer: 8, 0, 9, 0, 0, 0, 0, 0, 0, 0, 

Trying to get the array from ReadOnlyib for editing

相关用法

注：本文由纯净天空筛选整理自pawan_asipu大神的英文原创作品 LongBuffer asReadOnlyBuffer() method in Java。非经特殊声明，原始代码版权归原作者所有，本译文未经允许或授权，请勿转载或复制。