Class CharArrayWriter
- 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 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.
- Since:
- 1.1
Field Summary
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
Constructor | Description |
---|---|
CharArrayWriter() | Creates a new CharArrayWriter. |
CharArrayWriter(int initialSize) | Creates a new CharArrayWriter with the specified initial size. |
Method Summary
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 Detail
buf
protected char[] buf
The buffer where data is stored.
count
protected int count
The number of chars in the buffer.
Constructor Detail
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 Detail
write
public void write(int c)
Writes a character to the buffer.
write
public void write(char[] c, int off, int len)
Writes characters to the buffer.
- Specified by:
-
write
in classWriter
- Parameters:
-
c
- the data to be written -
off
- the start offset in the data -
len
- the number of chars that are written - Throws:
-
IndexOutOfBoundsException
- Ifoff
is negative, orlen
is negative, oroff + 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 classWriter
- Parameters:
-
str
- String to be written from -
off
- Offset from which to start reading characters -
len
- Number of characters to be written - Throws:
-
IndexOutOfBoundsException
- Ifoff
is negative, orlen
is negative, oroff + 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)
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.
- Specified by:
-
append
in interfaceAppendable
- Overrides:
-
append
in classWriter
- Parameters:
-
csq
- The character sequence to append. Ifcsq
isnull
, 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
out.write(csq.subSequence(start, end).toString())
- Specified by:
-
append
in interfaceAppendable
- Overrides:
-
append
in classWriter
- Parameters:
-
csq
- The character sequence from which a subsequence will be appended. Ifcsq
isnull
, then characters will be appended as ifcsq
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
- Ifstart
orend
are negative,start
is greater thanend
, orend
is greater thancsq.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
out.write(c)
- Specified by:
-
append
in interfaceAppendable
- Overrides:
-
append
in classWriter
- 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.
flush
public void flush()
Flush the stream.
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.