CharArrayWriter

public class CharArrayWriter
extends Writer

java.lang.Object
   ↳ java.io.Writer
     ↳ java.io.CharArrayWriter


This class implements a character buffer that can be used as an 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.

Summary

Fields

protected char[] buf

The buffer where data is stored.

protected int count

The number of chars in the buffer.

Inherited fields

Public constructors

CharArrayWriter()

Creates a new CharArrayWriter.

CharArrayWriter(int initialSize)

Creates a new CharArrayWriter with the specified initial size.

Public methods

CharArrayWriter append(char c)

Appends the specified character to this writer.

CharArrayWriter append(CharSequence csq, int start, int end)

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

CharArrayWriter append(CharSequence csq)

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

Writes characters to the buffer.

void writeTo(Writer out)

Writes the contents of the buffer to another character stream.

Inherited methods

Fields

buf

Added in API level 1
protected char[] buf

The buffer where data is stored.

count

Added in API level 1
protected int count

The number of chars in the buffer.

Public constructors

CharArrayWriter

Added in API level 1
public CharArrayWriter ()

Creates a new CharArrayWriter.

CharArrayWriter

Added in API level 1
public CharArrayWriter (int initialSize)

Creates a new CharArrayWriter with the specified initial size.

Parameters
initialSize int: an int specifying the initial buffer size.

Throws
IllegalArgumentException if initialSize is negative

Public methods

append

Added in API level 1
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

     out.write(c) 

Parameters
c char: The 16-bit character to append

Returns
CharArrayWriter This writer

append

Added in API level 1
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

     out.write(csq.subSequence(start, end).toString()) 

Parameters
csq CharSequence: 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 int: The index of the first character in the subsequence

end int: The index of the character following the last character in the subsequence

Returns
CharArrayWriter This writer

Throws
IndexOutOfBoundsException If start or end are negative, start is greater than end, or end is greater than csq.length()

append

Added in API level 1
public CharArrayWriter append (CharSequence csq)

Appends the specified character sequence to this writer.

An invocation of this method of the form out.append(csq) behaves in exactly the same way as the invocation

     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.

Parameters
csq CharSequence: The character sequence to append. If csq is null, then the four characters "null" are appended to this writer.

Returns
CharArrayWriter This writer

close

Added in API level 1
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.

flush

Added in API level 1
public void flush ()

Flush the stream.

reset

Added in API level 1
public void reset ()

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

size

Added in API level 1
public int size ()

Returns the current size of the buffer.

Returns
int an int representing the current size of the buffer.

toCharArray

Added in API level 1
public char[] toCharArray ()

Returns a copy of the input data.

Returns
char[] an array of chars copied from the input data.

toString

Added in API level 1
public String toString ()

Converts input data to a string.

Returns
String the string.

write

Added in API level 1
public void write (int c)

Writes a character to the buffer.

Parameters
c int: int specifying a character to be written

write

Added in API level 1
public void write (String str, 
                int off, 
                int len)

Write a portion of a string to the buffer.

Parameters
str String: String to be written from

off int: Offset from which to start reading characters

len int: 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

write

Added in API level 1
public void write (char[] c, 
                int off, 
                int len)

Writes characters to the buffer.

Parameters
c char: the data to be written

off int: the start offset in the data

len int: 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

writeTo

Added in API level 1
public void writeTo (Writer out)

Writes the contents of the buffer to another character stream.

Parameters
out Writer: the output stream to write to

Throws
IOException If an I/O error occurs.