Class StringWriter
- java.lang.Object
-
- java.io.Writer
-
- java.io.StringWriter
- All Implemented Interfaces:
-
Closeable
,Flushable
,Appendable
,AutoCloseable
public class StringWriter extends Writer
A character stream that collects its output in a string buffer, which can then be used to construct a string.
Closing a StringWriter
has no effect. The methods in this class can be called after the stream has been closed without generating an IOException
.
- Since:
- 1.1
Field Summary
Fields declared in class java.io.Writer
lock
Constructor Summary
Constructor | Description |
---|---|
StringWriter() | Create a new string writer using the default initial string-buffer size. |
StringWriter(int initialSize) | Create a new string writer using the specified initial string-buffer size. |
Method Summary
Modifier and Type | Method | Description |
---|---|---|
StringWriter | append(char c) | Appends the specified character to this writer. |
StringWriter | append(CharSequence csq) | Appends the specified character sequence to this writer. |
StringWriter | append(CharSequence csq,
int start,
int end) | Appends a subsequence of the specified character sequence to this writer. |
void | close() | Closing a |
void | flush() | Flush the stream. |
StringBuffer | getBuffer() | Return the string buffer itself. |
String | toString() | Return the buffer's current value as a string. |
void | write(char[] cbuf,
int off,
int len) | Write a portion of an array of characters. |
void | write(int c) | Write a single character. |
void | write(String str) | Write a string. |
void | write(String str,
int off,
int len) | Write a portion of a string. |
Methods declared in class java.io.Writer
nullWriter, write
Methods declared in class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait
Constructor Detail
StringWriter
public StringWriter()
Create a new string writer using the default initial string-buffer size.
StringWriter
public StringWriter(int initialSize)
Create a new string writer using the specified initial string-buffer size.
- Parameters:
-
initialSize
- The number ofchar
values that will fit into this buffer before it is automatically expanded - Throws:
-
IllegalArgumentException
- IfinitialSize
is negative
Method Detail
write
public void write(int c)
Write a single character.
write
public void write(char[] cbuf, int off, int len)
Write a portion of an array of characters.
- Specified by:
-
write
in classWriter
- Parameters:
-
cbuf
- Array of characters -
off
- Offset from which to start writing characters -
len
- Number of characters to write - 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)
Write a string.
write
public void write(String str, int off, int len)
Write a portion of a string.
- Overrides:
-
write
in classWriter
- Parameters:
-
str
- String to be written -
off
- Offset from which to start writing characters -
len
- Number of characters to write - Throws:
-
IndexOutOfBoundsException
- Ifoff
is negative, orlen
is negative, oroff + len
is negative or greater than the length of the given string
append
public StringWriter 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 StringWriter 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 StringWriter 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
toString
public String toString()
Return the buffer's current value as a string.
getBuffer
public StringBuffer getBuffer()
Return the string buffer itself.
- Returns:
- StringBuffer holding the current buffer value.
flush
public void flush()
Flush the stream.
close
public void close() throws IOException
Closing a StringWriter
has no effect. The methods in this class can be called after the stream has been closed without generating an IOException
.
- Specified by:
-
close
in interfaceAutoCloseable
- Specified by:
-
close
in interfaceCloseable
- Specified by:
-
close
in classWriter
- Throws:
-
IOException
- If an I/O error occurs