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Java ByteBuffer putDouble()用法及代码示例


putDouble(double value)

java.nio.ByteBuffer类的putDouble(double value)方法用于按当前字节顺序将包含给定double值的八个字节写入当前位置的此缓冲区中，然后将位置增加8。

用法:

public abstract ByteBuffer putDouble?(double value)

参数：此方法将要写入的双精度值。


返回值：此方法返回此缓冲区。

异常：此方法引发以下异常：

  • BufferOverflowException-如果此缓冲区的当前位置不小于其限制
  • ReadOnlyBufferException-如果此缓冲区是只读的

以下示例说明了putDouble(double value)方法：

范例1：

// Java program to demonstrate 
// putDouble() method 
  
import java.nio.*; 
import java.util.*; 
  
public class GFG { 
    public static void main(String[] args) 
    { 
  
        // Declaring the capacity of the ByteBuffer 
        int capacity = 24; 
  
        // Creating the ByteBuffer 
        try { 
  
            // creating object of ByteBuffer 
            // and allocating size capacity 
            ByteBuffer bb = ByteBuffer.allocate(capacity); 
  
            // putting the value in ByteBuffer 
            // using putDouble() method 
            bb.putDouble(23.4) 
                .putDouble(234.5) 
                .putDouble(34.56) 
                .rewind(); 
  
            // print the ByteBuffer 
            System.out.print("Original ByteBuffer:[ "); 
            for (int i = 1; i <= capacity / 8; i++) 
                System.out.print(bb.getDouble() + " "); 
            System.out.print("]"); 
        } 
  
        catch (BufferOverflowException e) { 
  
            System.out.println("Exception throws:" + e); 
        } 
  
        catch (ReadOnlyBufferException e) { 
  
            System.out.println("Exception throws:" + e); 
        } 
    } 
}
输出： 
Original ByteBuffer:[ 23.4 234.5 34.56 ]

范例2：演示BufferOverflowException。

// Java program to demonstrate 
// putDouble() method 
  
import java.nio.*; 
import java.util.*; 
  
public class GFG { 
    public static void main(String[] args) 
    { 
  
        // Declaring the capacity of the ByteBuffer 
        int capacity = 24; 
  
        // Creating the ByteBuffer 
        try { 
  
            // creating object of ByteBuffer 
            // and allocating size capacity 
            ByteBuffer bb = ByteBuffer.allocate(capacity); 
  
            // putting the value in ByteBuffer 
            // using putDouble() method 
            bb.putDouble(23.4) 
                .putDouble(234.5) 
                .putDouble(34.56) 
                .rewind(); 
  
            // print the ByteBuffer 
            System.out.print("Original ByteBuffer:[ "); 
            for (int i = 1; i <= capacity / 8; i++) 
                System.out.print(bb.getDouble() + " "); 
            System.out.print("]"); 
  
            // putting the value in ByteBuffer 
            // using putDouble() method 
            bb.putDouble(234.55); 
        } 
  
        catch (BufferOverflowException e) { 
            System.out.println("\n\nbuffer's current position"
                               + " is not smaller than"
                               + " its limit"); 
            System.out.println("Exception throws:" + e); 
        } 
  
        catch (ReadOnlyBufferException e) { 
  
            System.out.println("Exception throws:" + e); 
        } 
    } 
}
输出： 
Original ByteBuffer:[ 23.4 234.5 34.56 ]

buffer's current position is not smaller than its limit
Exception throws:java.nio.BufferOverflowException

范例3：演示ReadOnlyBufferException。

// Java program to demonstrate 
// putDouble() method 
  
import java.nio.*; 
import java.util.*; 
  
public class GFG { 
    public static void main(String[] args) 
    { 
  
        // Declaring the capacity of the ByteBuffer 
        int capacity = 24; 
  
        // Creating the ByteBuffer 
        try { 
  
            // creating object of ByteBuffer 
            // and allocating size capacity 
            ByteBuffer bb = ByteBuffer.allocate(capacity); 
  
            // putting the value in ByteBuffer 
            // using putDouble() method 
            bb.putDouble(23.4) 
                .putDouble(234.5) 
                .putDouble(34.56) 
                .rewind(); 
  
            // print the ByteBuffer 
            System.out.print("Original ByteBuffer:[ "); 
            for (int i = 1; i <= capacity / 8; i++) 
                System.out.print(bb.getDouble() + " "); 
            System.out.print("]"); 
  
            // Creating a read-only copy of ByteBuffer 
            // using asReadOnlyBuffer() method 
            ByteBuffer bb1 = bb.asReadOnlyBuffer(); 
  
            System.out.println("\n\nTrying to put the char value"
                               + " in read-only buffer"); 
  
            // putting the value in readonly ByteBuffer 
            // using putDouble() method 
            bb1.putDouble(234.5); 
        } 
  
        catch (BufferOverflowException e) { 
  
            System.out.println("Exception throws:" + e); 
        } 
  
        catch (ReadOnlyBufferException e) { 
  
            System.out.println("Exception throws:" + e); 
        } 
    } 
}
输出： 
Original ByteBuffer:[ 23.4 234.5 34.56 ]

Trying to put the char value in read-only buffer
Exception throws:java.nio.ReadOnlyBufferException

putDouble(int index, double value)

java.nio.ByteBuffer类的putDouble(int index，double value)方法用于以当前字节顺序将包含给定double值的八个字节按给定索引写入此缓冲区。


用法:

public abstract ByteBuffer putDouble(int index, double value)

参数：此方法将以下参数作为参数：

  • index：将写入字节的索引
  • value：要写入的双精度值

返回值：此方法返回此缓冲区。

异常：此方法引发以下异常：

  • IndexOutOfBoundsException-如果索引为负或不小于缓冲区的限制
  • ReadOnlyBufferException-如果此缓冲区是只读的

以下示例说明了put(int index，double value)方法：

范例1：

// Java program to demonstrate 
// putDouble() method 
  
import java.nio.*; 
import java.util.*; 
  
public class GFG { 
  
    public static void main(String[] args) 
    { 
  
        // Declaring the capacity of the ByteBuffer 
        int capacity = 24; 
  
        // Creating the ByteBuffer 
        try { 
  
            // creating object of ByteBuffer 
            // and allocating size capacity 
            ByteBuffer bb = ByteBuffer.allocate(capacity); 
  
            // putting the value in ByteBuffer 
            // using putDouble() at  index 0 
            bb.putDouble(0, 23.45); 
  
            // putting the value in ByteBuffer 
            // using putDouble() at  index 8 
            bb.putDouble(8, 34.56); 
  
            // putting the value in ByteBuffer 
            // using putDouble() at  index 16 
            bb.putDouble(16, 27.56); 
  
            // rewinding the ByteBuffer 
            bb.rewind(); 
  
            // print the ByteBuffer 
            System.out.print("Original ByteBuffer:[ "); 
            for (int i = 1; i <= capacity / 8; i++) 
                System.out.print(bb.getDouble() + " "); 
            System.out.print("]\n"); 
        } 
  
        catch (IndexOutOfBoundsException e) { 
  
            System.out.println("Exception throws:" + e); 
        } 
  
        catch (ReadOnlyBufferException e) { 
  
            System.out.println("Exception throws:" + e); 
        } 
    } 
}
输出： 
Original ByteBuffer:[ 23.45 34.56 27.56 ]

范例2：演示IndexOutOfBoundsException。

// Java program to demonstrate 
// putDouble() method 
  
import java.nio.*; 
import java.util.*; 
  
public class GFG { 
  
    public static void main(String[] args) 
    { 
  
        // Declaring the capacity of the ByteBuffer 
        int capacity = 24; 
  
        // Creating the ByteBuffer 
        try { 
  
            // creating object of ByteBuffer 
            // and allocating size capacity 
            ByteBuffer bb = ByteBuffer.allocate(capacity); 
  
            // putting the value in ByteBuffer 
            // using putDouble() at  index 0 
            bb.putDouble(0, 23.45); 
  
            // putting the value in ByteBuffer 
            // using putDouble() at  index 8 
            bb.putDouble(8, 34.56); 
  
            // putting the value in ByteBuffer 
            // using putDouble() at  index 16 
            bb.putDouble(16, 27.56); 
  
            // rewinding the ByteBuffer 
            bb.rewind(); 
  
            // print the ByteBuffer 
            System.out.print("Original ByteBuffer:[ "); 
            for (int i = 1; i <= capacity / 8; i++) 
                System.out.print(bb.getDouble() + " "); 
            System.out.print("]\n"); 
  
            // putting the value in ByteBuffer 
            // using putDouble() at  index -1 
            bb.putDouble(-1, 45.67); 
        } 
  
        catch (IndexOutOfBoundsException e) { 
            System.out.println("\nindex is negative or not smaller "
                               + "than the buffer's limit"); 
            System.out.println("Exception throws:" + e); 
        } 
  
        catch (ReadOnlyBufferException e) { 
  
            System.out.println("Exception throws:" + e); 
        } 
    } 
}
输出： 
Original ByteBuffer:[ 23.45 34.56 27.56 ]

index is negative or not smaller than the buffer's limit
Exception throws:java.lang.IndexOutOfBoundsException

范例3：演示ReadOnlyBufferException。

// Java program to demonstrate 
// putDouble() method 
  
import java.nio.*; 
import java.util.*; 
  
public class GFG { 
  
    public static void main(String[] args) 
    { 
  
        // Declaring the capacity of the ByteBuffer 
        int capacity = 8; 
  
        // Creating the ByteBuffer 
        try { 
  
            // creating object of ByteBuffer 
            // and allocating size capacity 
            ByteBuffer bb = ByteBuffer.allocate(capacity); 
  
            // Creating a read-only copy of ByteBuffer 
            // using asReadOnlyBuffer() method 
            ByteBuffer bb1 = bb.asReadOnlyBuffer(); 
  
            System.out.println("Trying to put the byte value"
                               + " in read-only buffer"); 
  
            // putting the value in readonly ByteBuffer 
            // using putDouble() method 
            bb1.putDouble(0, 'a'); 
        } 
  
        catch (IndexOutOfBoundsException e) { 
  
            System.out.println("Exception throws:" + e); 
        } 
  
        catch (ReadOnlyBufferException e) { 
  
            System.out.println("Exception throws:" + e); 
        } 
    } 
}
输出： 
Trying to put the byte value in read-only buffer
Exception throws:java.nio.ReadOnlyBufferException

参考：



相关用法


注：本文由纯净天空筛选整理自RohitPrasad3大神的英文原创作品 ByteBuffer putDouble() methods in Java with Examples。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。