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Java ByteBuffer putChar()用法及代码示例


putChar(char value)

java.nio.ByteBuffer类的putChar(char value)方法用于以当前字节顺序将包含给定char值的两个字节写入当前位置的此缓冲区中，然后将该位置加2。

用法:

public abstract ByteBuffer putChar(char value)

参数：此方法将要写入的char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putChar(char value)方法：

范例1：

// Java program to demonstrate 
// putChar() method 
  
import java.nio.*; 
import java.util.*; 
  
public class GFG { 
    public static void main(String[] args) 
    { 
  
        // Declaring the capacity of the ByteBuffer 
        int capacity = 6; 
  
        // Creating the ByteBuffer 
        try { 
  
            // creating object of ByteBuffer 
            // and allocating size capacity 
            ByteBuffer bb = ByteBuffer.allocate(capacity); 
  
            // putting the value in ByteBuffer 
            // using putChar() method 
            bb.putChar('a') 
                .putChar('b') 
                .putChar('c') 
                .rewind(); 
  
            // print the ByteBuffer 
            System.out.print("Original ByteBuffer:[ "); 
            for (int i = 1; i <= capacity / 2; i++) 
                System.out.print(bb.getChar() + " "); 
            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:[ a b c ]

范例2：演示BufferOverflowException。

// Java program to demonstrate 
// putChar() method 
  
import java.nio.*; 
import java.util.*; 
  
public class GFG { 
    public static void main(String[] args) 
    { 
  
        // Declaring the capacity of the ByteBuffer 
        int capacity = 6; 
  
        // Creating the ByteBuffer 
        try { 
  
            // creating object of ByteBuffer 
            // and allocating size capacity 
            ByteBuffer bb = ByteBuffer.allocate(capacity); 
  
            // putting the value in ByteBuffer 
            // using putChar() method 
            bb.putChar('a') 
                .putChar('b') 
                .putChar('c') 
                .rewind(); 
  
            // print the ByteBuffer 
            System.out.print("Original ByteBuffer:[ "); 
            for (int i = 1; i <= capacity / 2; i++) 
                System.out.print(bb.getChar() + " "); 
            System.out.print("]\n\n"); 
  
            // putting the value in ByteBuffer 
            // using putChar() method 
            bb.putChar('d'); 
        } 
  
        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); 
        } 
    } 
}
输出： 
Original ByteBuffer:[ a b c ]

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 
// putChar() method 
  
import java.nio.*; 
import java.util.*; 
  
public class GFG { 
    public static void main(String[] args) 
    { 
  
        // Declaring the capacity of the ByteBuffer 
        int capacity = 6; 
  
        // Creating the ByteBuffer 
        try { 
  
            // creating object of ByteBuffer 
            // and allocating size capacity 
            ByteBuffer bb = ByteBuffer.allocate(capacity); 
  
            // putting the value in ByteBuffer 
            // using putChar() method 
            bb.putChar('a') 
                .putChar('b') 
                .putChar('c') 
                .rewind(); 
  
            // print the ByteBuffer 
            System.out.print("Original ByteBuffer:[ "); 
            for (int i = 1; i <= capacity / 2; i++) 
                System.out.print(bb.getChar() + " "); 
            System.out.print("]\n"); 
  
            // Creating a read-only copy of ByteBuffer 
            // using asReadOnlyBuffer() method 
            ByteBuffer bb1 = bb.asReadOnlyBuffer(); 
  
            System.out.println("\nTrying to put the char value"
                               + " in read-only buffer"); 
  
            // putting the value in readonly ByteBuffer 
            // using putChart() method 
            bb1.putChar('d'); 
        } 
  
        catch (BufferOverflowException e) { 
            System.out.println("Exception throws:" + e); 
        } 
        catch (ReadOnlyBufferException e) { 
            System.out.println("Exception throws:" + e); 
        } 
    } 
}
输出： 
Original ByteBuffer:[ a b c ]

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

putChar(int index, char value)

java.nio.ByteBuffer类的putChar(int index，char value)方法用于将包含给定char值的两个字节(按当前字节顺序)写入给定索引处的此缓冲区中。


用法:

public abstract ByteBuffer putChar(int index, char 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char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putChar(int index，char value)方法：

范例1：

// Java program to demonstrate 
// putChar() method 
  
import java.nio.*; 
import java.util.*; 
  
public class GFG { 
  
    public static void main(String[] args) 
    { 
  
        // Declaring the capacity of the ByteBuffer 
        int capacity = 6; 
  
        // Creating the ByteBuffer 
        try { 
  
            // creating object of ByteBuffer 
            // and allocating size capacity 
            ByteBuffer bb = ByteBuffer.allocate(capacity); 
  
            // putting the value in ByteBuffer 
            // using putChar() at  index 0 
            bb.putChar(0, 'a'); 
  
            // putting the value in ByteBuffer 
            // using putChar() at  index 2 
            bb.putChar(2, 'b'); 
  
            // putting the value in ByteBuffer 
            // using putChar() at  index 1 
            bb.putChar(4, 'c'); 
  
            // rewinding the ByteBuffer 
            bb.rewind(); 
  
            // print the ByteBuffer 
            System.out.print("Original ByteBuffer:[ "); 
            for (int i = 1; i <= capacity / 2; i++) 
                System.out.print(bb.getChar() + " "); 
            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:[ a b c ]

范例2：演示IndexOutOfBoundsException。

// Java program to demonstrate 
// putChar() method 
  
import java.nio.*; 
import java.util.*; 
  
public class GFG { 
  
    public static void main(String[] args) 
    { 
  
        // Declaring the capacity of the ByteBuffer 
        int capacity = 6; 
  
        // Creating the ByteBuffer 
        try { 
  
            // creating object of ByteBuffer 
            // and allocating size capacity 
            ByteBuffer bb = ByteBuffer.allocate(capacity); 
  
            // putting the value in ByteBuffer 
            // using putChar() at  index 0 
            bb.putChar(0, 'a'); 
  
            // putting the value in ByteBuffer 
            // using putChar() at  index 2 
            bb.putChar(2, 'b'); 
  
            // putting the value in ByteBuffer 
            // using putChar() at  index 1 
            bb.putChar(4, 'c'); 
  
            // rewinding the ByteBuffer 
            bb.rewind(); 
  
            // print the ByteBuffer 
            System.out.print("Original ByteBuffer:[ "); 
            for (int i = 1; i <= capacity / 2; i++) 
                System.out.print(bb.getChar() + " "); 
            System.out.print("]\n"); 
  
            // putting the value in ByteBuffer 
            // using put() at  index -1 
            bb.putChar(-1, 'd'); 
        } 
  
        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:[ a b c ]

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 
// putChar() method 
  
import java.nio.*; 
import java.util.*; 
  
public class GFG { 
  
    public static void main(String[] args) 
    { 
  
        // Declaring the capacity of the ByteBuffer 
        int capacity = 6; 
  
        // 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 putChar() method 
            bb1.putChar(4, 'c'); 
        } 
  
        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 putChar() 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。