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java.lang.Object

java.io.Writer

java.io.CharArrayWriter

All Implemented Interfaces:: Closeable, Flushable, Appendable, AutoCloseable

public class CharArrayWriter extends Writer

This class implements a character buffer that can be used as a Writer. The buffer automatically grows when data is written to the stream. The data can be retrieved using toCharArray() and toString().

Note: Invoking close() on this class has no effect, and methods of this class can be called after the stream has closed without generating an IOException.

Since:: 1.1

Field Summary

Fields

Modifier and Type

Field

Description

protected char[]

buf

The buffer where data is stored.

protected int

count

The number of chars in the buffer.

Fields declared in class java.io.Writer
lock
Constructor Summary

Constructors

Constructor

Description

CharArrayWriter()

Creates a new CharArrayWriter.

CharArrayWriter(int initialSize)

Creates a new CharArrayWriter with the specified initial size.
Method Summary

All MethodsInstance MethodsConcrete Methods

Modifier and Type

Method

Description

CharArrayWriter

append(char c)

Appends the specified character to this writer.

CharArrayWriter

append(CharSequence csq)

Appends the specified character sequence to this writer.

CharArrayWriter

append(CharSequence csq, int start, int end)

Appends a subsequence of the specified character sequence to this writer.

void

close()

Close the stream.

void

flush()

Flush the stream.

void

reset()

Resets the buffer so that you can use it again without throwing away the already allocated buffer.

int

size()

Returns the current size of the buffer.

char[]

toCharArray()

Returns a copy of the input data.

String

toString()

Converts input data to a string.

void

write(char[] c, int off, int len)

Writes characters to the buffer.

void

write(int c)

Writes a character to the buffer.

void

write(String str, int off, int len)

Write a portion of a string to the buffer.

void

writeTo(Writer out)

Writes the contents of the buffer to another character stream.

Methods declared in class java.io.Writer
nullWriter, write, write

Methods declared in class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Details
- buf
  
  protected char[] buf
  
  The buffer where data is stored.
- count
  
  protected int count
  
  The number of chars in the buffer.
Constructor Details
- CharArrayWriter
  
  public CharArrayWriter()
  
  Creates a new CharArrayWriter.
- CharArrayWriter
  
  public CharArrayWriter(int initialSize)
  
  Creates a new CharArrayWriter with the specified initial size.
  
  Parameters:
  
  initialSize - an int specifying the initial buffer size.
  
  Throws:
  
  IllegalArgumentException - if initialSize is negative
Method Details
- write
  
  public void write(int c)
  
  Writes a character to the buffer.
  
  Overrides:
  
  write in class Writer
  
  Parameters:
  
  c - int specifying a character to be written
- write
  
  public void write(char[] c, int off, int len)
  
  Writes characters to the buffer.
  
  Specified by:
  
  write in class Writer
  
  Parameters:
  
  c - the data to be written
  
  off - the start offset in the data
  
  len - the number of chars that are written
  
  Throws:
  
  IndexOutOfBoundsException - If off is negative, or len is negative, or off + len is negative or greater than the length of the given array
- write
  
  public void write(String str, int off, int len)
  
  Write a portion of a string to the buffer.
  
  Overrides:
  
  write in class Writer
  
  Parameters:
  
  str - String to be written from
  
  off - Offset from which to start reading characters
  
  len - Number of characters to be written
  
  Throws:
  
  IndexOutOfBoundsException - If off is negative, or len is negative, or off + len is negative or greater than the length of the given string
- writeTo
  
  public void writeTo(Writer out) throws IOException
  
  Writes the contents of the buffer to another character stream.
  
  Parameters:
  
  out - the output stream to write to
  
  Throws:
  
  IOException - If an I/O error occurs.
- append
  public CharArrayWriter append(CharSequence csq)
  Appends the specified character sequence to this writer.
  An invocation of this method of the form out.append(csq) when csq is not null, behaves in exactly the same way as the invocation
  Copy [Copy snippet]
  out.write(csq.toString())
  Depending on the specification of toString for the character sequence csq, the entire sequence may not be appended. For instance, invoking the toString method of a character buffer will return a subsequence whose content depends upon the buffer's position and limit.
  Specified by:
  
  append in interface Appendable
  
  Overrides:
  
  append in class Writer
  
  Parameters:
  
  csq - The character sequence to append. If csq is null, then the four characters "null" are appended to this writer.
  
  Returns:
  
  This writer
  
  Since:
  
  1.5
- append
  public CharArrayWriter append(CharSequence csq, int start, int end)
  Appends a subsequence of the specified character sequence to this writer.
  An invocation of this method of the form out.append(csq, start, end) when csq is not null, behaves in exactly the same way as the invocation
  Copy [Copy snippet]
  out.write(csq.subSequence(start, end).toString())
  Specified by:
  
  append in interface Appendable
  
  Overrides:
  
  append in class Writer
  
  Parameters:
  
  csq - The character sequence from which a subsequence will be appended. If csq is null, then characters will be appended as if csq contained the four characters "null".
  
  start - The index of the first character in the subsequence
  
  end - The index of the character following the last character in the subsequence
  
  Returns:
  
  This writer
  
  Throws:
  
  IndexOutOfBoundsException - If start or end are negative, start is greater than end, or end is greater than csq.length()
  
  Since:
  
  1.5
- append
  public CharArrayWriter append(char c)
  Appends the specified character to this writer.
  An invocation of this method of the form out.append(c) behaves in exactly the same way as the invocation
  Copy [Copy snippet]
  out.write(c)
  Specified by:
  
  append in interface Appendable
  
  Overrides:
  
  append in class Writer
  
  Parameters:
  
  c - The 16-bit character to append
  
  Returns:
  
  This writer
  
  Since:
  
  1.5
- reset
  
  public void reset()
  
  Resets the buffer so that you can use it again without throwing away the already allocated buffer.
- toCharArray
  
  public char[] toCharArray()
  
  Returns a copy of the input data.
  
  Returns:
  
  an array of chars copied from the input data.
- size
  
  public int size()
  
  Returns the current size of the buffer.
  
  Returns:
  
  an int representing the current size of the buffer.
- toString
  
  public String toString()
  
  Converts input data to a string.
  
  Overrides:
  
  toString in class Object
  
  Returns:
  
  the string.
- flush
  
  public void flush()
  
  Flush the stream.
  The flush method of CharArrayWriter does nothing.
  
  Specified by:
  
  flush in interface Flushable
  
  Specified by:
  
  flush in class Writer
- close
  
  public void close()
  
  Close the stream. This method does not release the buffer, since its contents might still be required. Note: Invoking this method in this class will have no effect.
  
  Specified by:
  
  close in interface AutoCloseable
  
  Specified by:
  
  close in interface Closeable
  
  Specified by:
  
  close in class Writer

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Class CharArrayWriter

Field Summary

Fields declared in class java.io.Writer

Constructor Summary

Method Summary

Methods declared in class java.io.Writer

Methods declared in class java.lang.Object

Field Details

buf

count

Constructor Details

CharArrayWriter

CharArrayWriter

Method Details

write

write

write

writeTo

append

append

append

reset

toCharArray

size

toString

flush

close