ByteBuffer getChar() method in Java with Examples
Last Updated :
19 Sep, 2023
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getChar()
The getChar() method of java.nio.ByteBuffer class is used to get method for reading a char value
Reads the next two bytes at this buffer’s current position, composing them into a char value according to the current byte order, and then increments the position by two.
Syntax:
public abstract char getChar()
Return Value: This method returns the char value at the buffer’s current position
Throws: This method throws BufferUnderflowException – If the buffer’s current position is not smaller than its limit, then this exception is thrown.
Below are the examples to illustrate the getChar() method:
Examples 1:
// Java program to demonstrate // getChar() method import java.nio.*; import java.util.*; public class GFG { public static void main(String[] args) { // Declaring the capacity of the ByteBuffer int capacity = 50; // Creating the ByteBuffer try { // creating object of ByteBuffer // and allocating size capacity ByteBuffer bb = ByteBuffer.allocate(capacity); // putting the string in the bytebuffer bb.asCharBuffer().put("Geeks"); // rewind the Bytebuffer bb.rewind(); // Declaring the variable char c; // print the ByteBuffer System.out.println("Original ByteBuffer: "); while ((c = bb.getChar()) != 0) System.out.print(c + " "); // rewind the Bytebuffer bb.rewind(); // Reads the char at this buffer's current position // using getChar() method char value = bb.getChar(); // print the char value System.out.println("\n\nByte Value: " + value); // Reads the char at this buffer's next position // using getChar() method char value1 = bb.getChar(); // print the char value System.out.print("\nNext Byte Value: " + value1); } catch (IllegalArgumentException e) { System.out.println("\nException Thrown: " + e); } catch (ReadOnlyBufferException e) { System.out.println("\nException Thrown: " + e); } catch (BufferUnderflowException e) { System.out.println("\nException Thrown: " + e); } } } |
Output:
Original ByteBuffer: G e e k s Byte Value: G Next Byte Value: e
Examples 2:
// Java program to demonstrate // getChar() method import java.nio.*; import java.util.*; public class GFG { public static void main(String[] args) { // Declaring the capacity of the ByteBuffer int capacity = 8; // Creating the ByteBuffer try { // creating object of ByteBuffer // and allocating size capacity ByteBuffer bb = ByteBuffer.allocate(capacity); // putting the string in the bytebuffer bb.asCharBuffer().put("abc"); // rewind the Bytebuffer bb.rewind(); // Declaring the variable char c; // print the ByteBuffer System.out.print("Original ByteBuffer: "); while ((c = bb.getChar()) != 0) System.out.print(c + " "); // rewind the Bytebuffer bb.rewind(); // Reads the char at this buffer's current position // using getChar() method char value = bb.getChar(); // print the char value System.out.println("\n\nFirst char Value: " + value); // Reads the char at this buffer's next position // using getChar() method char value1 = bb.getChar(); // print the char value System.out.println("\nSecond char Value: " + value1); // Reads the char at this buffer's next position // using getChar() method char value2 = bb.getChar(); // print the char value System.out.println("\nThird char Value: " + value2); // Reads the char at this buffer's next position // using getChar() method System.out.print("\nsince the buffer current position is incremented"); System.out.print(" to greater than its limit "); char value3 = bb.getChar(); char value4 = bb.getChar(); } catch (BufferOverflowException e) { System.out.println("\nException Thrown: " + e); } catch (ReadOnlyBufferException e) { System.out.println("\nException Thrown: " + e); } catch (BufferUnderflowException e) { System.out.println("\nException Thrown: " + e); } } } |
Output:
Original ByteBuffer: a b c First char Value: a Second char Value: b Third char Value: c since the buffer current position is incremented to greater than its limit Exception Thrown: java.nio.BufferUnderflowException
get(int index)
The get(int index) method of ByteBuffer is used to reads two bytes at the given index, composing them into a char value according to the current byte order.
Syntax:
public abstract char getChar(int index)
Parameters: This method takes index (The index from which the Byte will be read) as a parameter.
Return Value: This method returns the char value at the given index.
Exception: This method throws IndexOutOfBoundsException. If index is negative or not smaller than the buffer’s limit this exception is thrown.
Below are the examples to illustrate the get(int index) method:
Examples 1:
// Java program to demonstrate // getChar() method import java.nio.*; import java.util.*; public class GFG { public static void main(String[] args) { // Declaring the capacity of the ByteBuffer int capacity = 50; // Creating the ByteBuffer try { // creating object of ByteBuffer // and allocating size capacity ByteBuffer bb = ByteBuffer.allocate(capacity); // putting the string in the bytebuffer bb.asCharBuffer().put("abc"); // rewind the Bytebuffer bb.rewind(); // Declaring the variable char c; // print the ByteBuffer System.out.print("Original ByteBuffer: "); while ((c = bb.getChar()) != 0) System.out.print(c + " "); // rewind the Bytebuffer bb.rewind(); // Reads the char at this buffer's at index 0 // using getChar() method char value0 = bb.getChar(0); // print the char value System.out.println("\n\nchar Value at index 0: " + value0); // Reads the char at this buffer's at index 2 // using getChar() method char value1 = bb.getChar(2); // print the char value System.out.println("\nchar Value at index 2: " + value1); // Reads the char at this buffer's at index 4 // using getChar() method char value2 = bb.getChar(4); // print the char value System.out.println("\nchar Value at index 4: " + value2); } catch (IllegalArgumentException e) { System.out.println("\nException Thrown: " + e); } catch (ReadOnlyBufferException e) { System.out.println("\nException Thrown: " + e); } catch (BufferUnderflowException e) { System.out.println("\nException Thrown: " + e); } } } |
Output:
Original ByteBuffer: a b c char Value at index 0: a char Value at index 2: b char Value at index 4: c
Examples 2:
// Java program to demonstrate // getChar() method import java.nio.*; import java.util.*; public class GFG { public static void main(String[] args) { // Declaring the capacity of the ByteBuffer int capacity = 50; // Creating the ByteBuffer try { // creating object of ByteBuffer // and allocating size capacity ByteBuffer bb = ByteBuffer.allocate(capacity); // putting the string in the bytebuffer bb.asCharBuffer().put("abc"); // rewind the Bytebuffer bb.rewind(); // Declaring the variable char c; // print the ByteBuffer System.out.print("Original ByteBuffer: "); while ((c = bb.getChar()) != 0) System.out.print(c + " "); // rewind the Bytebuffer bb.rewind(); // Reads the char at this buffer's at index 0 // using getChar() method char value0 = bb.getChar(0); // print the char value System.out.println("\n\nchar Value at index 0: " + value0); // Reads the char at this buffer's at index 2 // using getChar() method char value1 = bb.getChar(2); // print the char value System.out.println("\nchar Value at index 2: " + value1); // Reads the char at this buffer's at index 4 // using getChar() method System.out.println("\nTrying to get the char" + " at negative index "); char value2 = bb.getChar(-4); } catch (IndexOutOfBoundsException e) { System.out.println("\nException Thrown: " + e); } catch (ReadOnlyBufferException e) { System.out.println("\nException Thrown: " + e); } catch (BufferUnderflowException e) { System.out.println("\nException Thrown: " + e); } } } |
Output:
Original ByteBuffer: a b c char Value at index 0: a char Value at index 2: b Trying to get the char at a negative index Exception Thrown: java.lang.IndexOutOfBoundsException
