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Java ByteBuffer put()方法用法及代碼示例


put(byte b)

java.nio.ByteBuffer類的put(byte b)方法用於將給定字節寫入當前位置的新創建的字節緩衝區中，然後遞增該位置。

用法:

public abstract ByteBuffer put(byte f)

參數：該方法將字節值b作為要寫入字節緩衝區的參數。



返回值：此方法返回此緩衝區，在其中插入字節值。

異常：此方法引發以下異常：

  • BufferOverflowException-如果此緩衝區的當前位置不小於其限製
  • ReadOnlyBufferException-如果此緩衝區是隻讀的

下麵是說明put(byte b)方法的示例：

範例1：

// Java program to demonstrate 
// put() method 
  
import java.nio.*; 
import java.util.*; 
  
public class GFG { 
    public static void main(String[] args) 
    { 
  
        // Declaring the capacity of the ByteBuffer 
        int capacity = 3; 
  
        // Creating the ByteBuffer 
        try { 
  
            // creating object of ByteBuffer 
            // and allocating size capacity 
            ByteBuffer bb = ByteBuffer.allocate(capacity); 
  
            // putting the value in ByteBuffer using put() method 
            bb.put((byte)10) 
                .put((byte)20) 
                .put((byte)30) 
                .rewind(); 
  
            // print the ByteBuffer 
            System.out.println("Original ByteBuffer:  "
                               + Arrays.toString(bb.array())); 
        } 
  
        catch (BufferOverflowException e) { 
  
            System.out.println("Exception throws:" + e); 
        } 
  
        catch (ReadOnlyBufferException e) { 
  
            System.out.println("Exception throws:" + e); 
        } 
    } 
}
輸出： 
Original ByteBuffer: [10, 20, 30]

範例2：演示BufferOverflowException。

// Java program to demonstrate 
// put() method 
  
import java.nio.*; 
import java.util.*; 
  
public class GFG { 
    public static void main(String[] args) 
    { 
  
        // Declaring the capacity of the ByteBuffer 
        int capacity = 3; 
  
        // Creating the ByteBuffer 
        try { 
  
            // creating object of ByteBuffer 
            // and allocating size capacity 
            ByteBuffer bb = ByteBuffer.allocate(capacity); 
  
            // putting the value in ByteBuffer using put() method 
            bb.put((byte)10) 
                .put((byte)20) 
                .put((byte)30); 
  
            // print the ByteBuffer 
            System.out.println("Original ByteBuffer:  "
                               + Arrays.toString(bb.array())); 
  
            // again putting the value in ByteBuffer 
            // using put() method 
            System.out.println("\nBuffer position:"
                               + bb.position()); 
            bb.put((byte)40); 
        } 
  
        catch (BufferOverflowException e) { 
  
            System.out.println("buffer's current position "
                               + "is not smaller than its limit"); 
            System.out.println("Exception throws:" + e); 
        } 
  
        catch (ReadOnlyBufferException e) { 
  
            System.out.println("Exception throws:" + e); 
        } 
    } 
}
輸出： 
Original ByteBuffer: [10, 20, 30]

Buffer position:3
buffer's current position is not smaller than its limit
Exception throws:java.nio.BufferOverflowException

範例3：演示ReadOnlyBufferException。

// Java program to demonstrate 
// put() method 
  
import java.nio.*; 
import java.util.*; 
  
public class GFG { 
    public static void main(String[] args) 
    { 
  
        // Declaring the capacity of the ByteBuffer 
        int capacity = 3; 
  
        // Creating the ByteBuffer 
        try { 
  
            // creating object of ByteBuffer 
            // and allocating size capacity 
            ByteBuffer bb = ByteBuffer.allocate(capacity); 
  
            // putting the value in ByteBuffer using put() method 
            bb.put((byte)10) 
                .put((byte)20) 
                .put((byte)30); 
  
            // print the ByteBuffer 
            System.out.println("Original ByteBuffer:  "
                               + Arrays.toString(bb.array())); 
  
            // Creating a read-only copy of ByteBuffer 
            // using asReadOnlyBuffer() method 
            ByteBuffer bb1 = bb.asReadOnlyBuffer(); 
  
            System.out.println("\nTrying to put the byte value"
                               + " in read only buffer"); 
  
            // putting the value in readonly ByteBuffer 
            // using put() method 
            bb1.put((byte)40); 
        } 
  
        catch (BufferOverflowException e) { 
  
            System.out.println("buffer's current position "
                               + "is not smaller than its limit"); 
            System.out.println("Exception throws:" + e); 
        } 
  
        catch (ReadOnlyBufferException e) { 
  
            System.out.println("Exception throws:" + e); 
        } 
    } 
}
輸出： 
Original ByteBuffer: [10, 20, 30]

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

參考： https://docs.oracle.com/javase/9/docs/api/java/nio/ByteBuffer.html#put-byte-



put(int index, byte f)

java.nio.ByteBuffer類的put(int index，byte f)方法用於將給定字節寫入給定索引處的緩衝區。

用法:

public abstract ByteBuffer put(int index, byte f)

參數：此方法將以下參數作為參數：

  • index：將寫入字節的索引
  • f：要寫入的字節值

返回值：此方法返回此緩衝區。

異常：此方法引發以下異常：

  • IndexOutOfBoundsException-如果索引為負或不小於緩衝區的限製
  • ReadOnlyBufferException-如果此緩衝區是隻讀的

以下示例說明了put(int index，byte f)方法：

範例1：

// Java program to demonstrate 
// put() method 
  
import java.nio.*; 
import java.util.*; 
  
public class GFG { 
  
    public static void main(String[] args) 
    { 
  
        // Declaring the capacity of the ByteBuffer 
        int capacity = 3; 
  
        // Creating the ByteBuffer 
        try { 
  
            // creating object of ByteBuffer 
            // and allocating size capacity 
            ByteBuffer bb = ByteBuffer.allocate(capacity); 
  
            // putting the value in ByteBuffer using put() at  index 0 
            bb.put(0, (byte)10); 
  
            // putting the value in ByteBuffer using put() at  index 2 
            bb.put(2, (byte)20); 
  
            // putting the value in ByteBuffer using put() at  index 1 
            bb.put(1, (byte)30); 
  
            // rewinding the ByteBuffer 
            bb.rewind(); 
  
            // print the ByteBuffer 
            System.out.println("Original ByteBuffer:  "
                               + Arrays.toString(bb.array())); 
        } 
  
        catch (IndexOutOfBoundsException e) { 
  
            System.out.println("Exception throws:" + e); 
        } 
  
        catch (ReadOnlyBufferException e) { 
  
            System.out.println("Exception throws:" + e); 
        } 
    } 
}
輸出： 
Original ByteBuffer: [10, 30, 20]

範例2：演示IndexOutOfBoundsException。

// Java program to demonstrate 
// put() method 
  
import java.nio.*; 
import java.util.*; 
  
public class GFG { 
  
    public static void main(String[] args) 
    { 
  
        // Declaring the capacity of the ByteBuffer 
        int capacity = 3; 
  
        // Creating the ByteBuffer 
        try { 
  
            // creating object of ByteBuffer 
            // and allocating size capacity 
            ByteBuffer bb = ByteBuffer.allocate(capacity); 
  
            // putting the value in ByteBuffer using put() at  index 0 
            bb.put(0, (byte)10); 
  
            // putting the value in ByteBuffer using put() at  index 2 
            bb.put(2, (byte)20); 
  
            // putting the value in ByteBuffer using put() at  index 1 
            bb.put(1, (byte)30); 
  
            // rewinding the ByteBuffer 
            bb.rewind(); 
  
            // print the ByteBuffer 
            System.out.println("Original ByteBuffer:  "
                               + Arrays.toString(bb.array())); 
  
            // putting the value in ByteBuffer using put() at  index -1 
            bb.put(-1, (byte)40); 
        } 
  
        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); 
        } 
    } 
}
輸出： 
Original ByteBuffer: [10, 30, 20]

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

範例3：演示ReadOnlyBufferException。

// Java program to demonstrate 
// put() method 
  
import java.nio.*; 
import java.util.*; 
  
public class GFG { 
    public static void main(String[] args) 
    { 
  
        // Declaring the capacity of the ByteBuffer 
        int capacity = 3; 
  
        // Creating the ByteBuffer 
        try { 
  
            // creating object of ByteBuffer 
            // and allocating size capacity using allocate() method 
            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 put() method 
            bb1.put(0, (byte)10); 
        } 
  
        catch (IndexOutOfBoundsException e) { 
  
            System.out.println("Exception throws:" + e); 
        } 
  
        catch (ReadOnlyBufferException e) { 
  
            System.out.println("Exception throws:" + e); 
        } 
    } 
}
輸出： 
Trying to put the byte value in read only buffer
Exception throws:java.nio.ReadOnlyBufferException

參考： https://docs.oracle.com/javase/9/docs/api/java/nio/ByteBuffer.html#put-int-byte-




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注：本文由純淨天空篩選整理自RohitPrasad3大神的英文原創作品 ByteBuffer put() methods in Java with Examples | Set -1。非經特殊聲明，原始代碼版權歸原作者所有，本譯文未經允許或授權，請勿轉載或複製。