java.nio.FloatBuffer类的arrayOffset()方法用于返回缓冲区第一个元素的缓冲区支持数组内的偏移量。这意味着,如果此缓冲区由数组支持,则缓冲区位置p对应于数组索引p + arrayOffset()。
为了检查此缓冲区是否具有后备数组,可以使用hasArray()方法。它确保此缓冲区具有可访问的后备数组。
用法:
public final int arrayOffset()
返回值:此方法返回此缓冲区数组中第一个元素的偏移量。
异常:如果此缓冲区由数组支持,但此方法是只读的,则此方法将引发ReadOnlyBufferException
以下示例程序旨在说明arrayOffset()方法。
范例1:
// Java program to demonstrate
// arrayOffset() method
import java.nio.*;
import java.util.*;
public class GFG {
public static void main(String[] args)
{
// Declaring the capacity of the FloatBuffer
int capacity = 10;
// Creating the FloatBuffer
try {
// creating object of floatbuffer
// and allocating size capacity
FloatBuffer fb = FloatBuffer.allocate(capacity);
// putting the value in floatbuffer
fb.put(8.56F);
fb.put(2, 9.61F);
// print the FloatBuffer
System.out.println("FloatBuffer: "
+ Arrays.toString(fb.array()));
// print the arrayOffset
System.out.println("arrayOffset: "
+ fb.arrayOffset());
}
catch (IllegalArgumentException e) {
System.out.println("IllegalArgumentException catched");
}
catch (ReadOnlyBufferException e) {
System.out.println("Exception throws" + e);
}
}
}
输出:
FloatBuffer: [8.56, 0.0, 9.61, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0] arrayOffset: 0
范例2:演示ReadOnlyBufferException
// Java program to demonstrate
// arrayOffset() method
import java.nio.*;
import java.util.*;
public class GFG {
public static void main(String[] args)
{
// Declaring the capacity of the FloatBuffer
int capacity = 10;
// Creating the FloatBuffer
try {
// creating object of floatbuffer
// and allocating size capacity
FloatBuffer fb = FloatBuffer.allocate(capacity);
// putting the value in floatbuffer
fb.put(8.56F);
fb.put(2, 9.61F);
fb.rewind();
// Creating a read-only copy of FloatBuffer
// using asReadOnlyBuffer() method
FloatBuffer fb1 = fb.asReadOnlyBuffer();
// print the FloatBuffer
System.out.print("Read only buffer : ");
while (fb1.hasRemaining())
System.out.print(fb1.get() + ", ");
// next line
System.out.println("");
// print the arrayOffset
System.out.println("\nTry to print the array offset"
+ " of read only buffer");
System.out.println("arrayOffset: " + fb1.arrayOffset());
}
catch (IllegalArgumentException e) {
System.out.println("Exception throws: " + e);
}
catch (ReadOnlyBufferException e) {
System.out.println("Exception throws: " + e);
}
}
}
输出:
Read only buffer : 8.56, 0.0, 9.61, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, Try to print the array offset of read only buffer Exception throws: java.nio.ReadOnlyBufferException
相关用法
- Java Buffer arrayOffset()用法及代码示例
- Java ShortBuffer arrayOffset()用法及代码示例
- Java ByteBuffer arrayOffset()用法及代码示例
- Java DoubleBuffer arrayOffset()用法及代码示例
- Java FloatBuffer asReadOnlyBuffer()用法及代码示例
- Java FloatBuffer duplicate()用法及代码示例
- Java FloatBuffer allocate()用法及代码示例
- Java FloatBuffer hasArray()用法及代码示例
- Java FloatBuffer compareTo()用法及代码示例
- Java FloatBuffer limit()用法及代码示例
- Java FloatBuffer equals()用法及代码示例
- Java FloatBuffer array()用法及代码示例
- Java FloatBuffer slice()用法及代码示例
- Java FloatBuffer compact()用法及代码示例
- Java FloatBuffer wrap()用法及代码示例
注:本文由纯净天空筛选整理自RohitPrasad3大神的英文原创作品 FloatBuffer arrayOffset() method 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。