Java FloatBuffer array()方法及实例

java.nio.FloatBuffer 类的 array() 方法是用来返回支持这个缓冲区的浮点数组。对这个缓冲区内容的修改将导致返回数组的内容被修改，反之亦然。在调用此方法之前，先使用Invoke()和hasArray()方法，以确保此缓冲区有一个可访问的支持数组。

语法:

public final float[] array()

返回值： 该方法返回支持该缓冲区的数组。

抛出： 该方法抛出 ReadOnlyBufferException （如果这个缓冲区是由一个数组支持的，但是是只读的）。

下面的程序说明了 array() 方法。

例子 1 :

// Java program to demonstrate// array() 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();              // getting array from fb FloatBuffer using array() method            float[] fbb = fb.array();              // printing the FloatBuffer fb            System.out.println("FloatBuffer:  "                               + Arrays.toString(fbb));        }          catch (IllegalArgumentException e) {              System.out.println("IllegalArgumentException catched");        }          catch (ReadOnlyBufferException e) {              System.out.println("ReadOnlyBufferException catched");        }    }}

输出。

FloatBuffer:  [8.56, 0.0, 9.61, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0]

例子 2 :

// Java program to demonstrate// array() method  import java.nio.*;import java.util.*;  public class GFG {    public static void main(String[] args)    {          // Declaring the capacity of the fb        int capacity1 = 10;          // Declaring the capacity of the fb1        int capacity2 = 5;          // Creating the FloatBuffer        try {            //            // fb            //            // creating object of floatbuffer fb            // and allocating size capacity            FloatBuffer fb = FloatBuffer.allocate(capacity1);              // putting the value in fb            fb.put(9.56F);            fb.put(2, 7.61F);            fb.put(3, 4.61F);            fb.rewind();              // print the FloatBuffer            System.out.println("FloatBuffer fb: "                               + Arrays.toString(fb.array()));              //            // fb1            //            // creating object of floatbuffer fb1            // and allocating size capacity            FloatBuffer fb1 = FloatBuffer.allocate(capacity2);              // putting the value in fb1            fb1.put(1, 4.56F);            fb1.put(2, 6.45F);            fb1.rewind();              // print the FloatBuffer            System.out.println("\nFloatBuffer fb1:  "                               + Arrays.toString(fb1.array()));              // Creating a read-only copy of FloatBuffer            // using asReadOnlyBuffer() method            FloatBuffer readOnlyFb = fb.asReadOnlyBuffer();              // print the FloatBuffer            System.out.print("\nReadOnlyBuffer FloatBuffer: ");              while (readOnlyFb.hasRemaining())                System.out.print(readOnlyFb.get() + ", ");              // try to change readOnlyFb            System.out.println("\n\nTrying to get the array"                               + " from ReadOnlyFb for editing");              float[] fbarr = readOnlyFb.array();        }        catch (IllegalArgumentException e) {            System.out.println("IllegalArgumentException catched");        }        catch (ReadOnlyBufferException e) {            System.out.println("Exception thrown: " + e);        }    }}

输出。

FloatBuffer fb: [9.56, 0.0, 7.61, 4.61, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0]FloatBuffer fb1:  [0.0, 4.56, 6.45, 0.0, 0.0]ReadOnlyBuffer FloatBuffer: 9.56, 0.0, 7.61, 4.61, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, Trying to get the array from ReadOnlyFb for editingException thrown: java.nio.ReadOnlyBufferException