Java 中的 ByteBuffer putDouble()方法示例
原文:https://www . geeksforgeeks . org/bytebuffer-put double-methods-in-Java-with-examples/
双精度值
java.nio.ByteBuffer 类的 putDouble(Double value) 方法用于按照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缓冲区，然后将该位置增加八。
语法:
public abstract ByteBuffer putDouble?(double value)
参数:该方法取要写入的双精度值。
返回值:这个方法返回这个缓冲区。
异常:此方法抛出以下异常:
- Bufferovflowexception- If the current position of this buffer is not less than its limit
- ReadonlyBufferenexception- If this buffer is read-only,
下面是举例说明 putDouble(双精度值)方法的例子:
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 ]
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
示例 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
版权属于：月萌API www.moonapi.com，转载请注明出处
