java.io
Class StringWriter

java.lang.Object
  java.io.Writer
      java.io.StringWriter

All Implemented Interfaces:

Closeable, Flushable, Appendable

public class StringWriter
extends Writer

StringWriter is an class for writing Character Streams to a StringBuffer. The characters written can then be returned as a String. This is used for capturing output sent to a Writer by substituting a StringWriter.

See Also:

StringReader

Field Summary

Fields inherited from class java.io.Writer

lock, TOKEN_NULL

Constructor Summary

StringWriter()
Constructs a new StringWriter which has a StringBuffer allocated with the default size of 16 characters.

StringWriter(int initialSize)
Constructs a new StringWriter which has a StringBuffer allocated with the size of initialSize characters.

Method Summary

StringWriter	append(char c) Append a char cto the StringWriter.
StringWriter	append(CharSequence csq) Append a CharSequence csq to the StringWriter.
StringWriter	append(CharSequence csq, int start, int end) Append a subsequence of a CharSequence csq to the StringWriter.
void	close() Close this Writer.
void	flush() Flush this Writer.
StringBuffer	getBuffer() Answer the contents of this StringWriter as a StringBuffer.
String	toString() Answer the contents of this StringWriter as a String.
void	write(char[] cbuf, int offset, int count) Writes count characters starting at offset in cbuf to this StringWriter.
void	write(int oneChar) Writes the specified character oneChar to this StringWriter.
void	write(String str) Writes the characters from the String str to this StringWriter.
void	write(String str, int offset, int count) Writes count number of characters starting at offset from the String str to this StringWriter.

Methods inherited from class java.io.Writer

write

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

StringWriter

public StringWriter()

Constructs a new StringWriter which has a StringBuffer allocated with the default size of 16 characters. The StringBuffer is also the lock used to synchronize access to this Writer.

StringWriter

public StringWriter(int initialSize)

Constructs a new StringWriter which has a StringBuffer allocated with the size of initialSize characters. The StringBuffer is also the lock used to synchronize access to this Writer.

Parameters:

initialSize - the intial number of characters

Method Detail

close

public void close()
           throws IOException

Close this Writer. This is the concrete implementation required. This particular implementation does nothing.

Specified by:

close in interface Closeable

Specified by:

close in class Writer

Throws:

IOException - If an IO error occurs closing this StringWriter.

flush

public void flush()

Flush this Writer. This is the concrete implementation required. This particular implementation does nothing.

Specified by:

flush in interface Flushable

Specified by:

flush in class Writer

getBuffer

public StringBuffer getBuffer()

Answer the contents of this StringWriter as a StringBuffer. Any changes made to the StringBuffer by the receiver or the caller are reflected in this StringWriter.

Returns:

this StringWriters local StringBuffer.

toString

public String toString()

Answer the contents of this StringWriter as a String. Any changes made to the StringBuffer by the receiver after returning will not be reflected in the String returned to the caller.

Overrides:

toString in class Object

Returns:

this StringWriters current contents as a String.

write

public void write(char[] cbuf,
                  int offset,
                  int count)

Writes count characters starting at offset in cbuf to this StringWriter.

Specified by:

write in class Writer

Parameters:

cbuf - the non-null array containing characters to write.

offset - offset in buf to retrieve characters

count - maximum number of characters to write

Throws:

ArrayIndexOutOfBoundsException - If offset or count are outside of bounds.

write

public void write(int oneChar)

Writes the specified character oneChar to this StringWriter. This implementation writes the low order two bytes to the Stream.

Overrides:

write in class Writer

Parameters:

oneChar - The character to write

write

public void write(String str)

Writes the characters from the String str to this StringWriter.

Overrides:

write in class Writer

Parameters:

str - the non-null String containing the characters to write.

write

public void write(String str,
                  int offset,
                  int count)

Writes count number of characters starting at offset from the String str to this StringWriter.

Overrides:

write in class Writer

Parameters:

str - the non-null String containing the characters to write.

offset - the starting point to retrieve characters.

count - the number of characters to retrieve and write.

Throws:

ArrayIndexOutOfBoundsException - If offset or count are outside of bounds.

append

public StringWriter append(char c)

Append a char cto the StringWriter. The StringWriter.append(c) works the same way as StringWriter.write(c).

Specified by:

append in interface Appendable

Overrides:

append in class Writer

Parameters:

c - The character appended to the StringWriter.

Returns:

The StringWriter.

append

public StringWriter append(CharSequence csq)

Append a CharSequence csq to the StringWriter. The StringWriter.append(csq) works the same way as StringWriter.write(csq.toString()). If csq is null, then "null" will be substituted for csq.

Specified by:

append in interface Appendable

Overrides:

append in class Writer

Parameters:

csq - The CharSequence appended to the StringWriter.

Returns:

The StringWriter

append

public StringWriter append(CharSequence csq,
                           int start,
                           int end)

Append a subsequence of a CharSequence csq to the StringWriter. The first char and the last char of the subsequnce is specified by the parameter start and end. The StringWriter.append(csq) works the same way as StringWriter.write(csq.subSequence(start,end).toString).If csq is null, then "null" will be substituted for csq. s

Specified by:

append in interface Appendable

Overrides:

append in class Writer

Parameters:

csq - The CharSequence appended to the StringWriter.

start - The index of the first char in the CharSequence appended to the StringWriter.

end - The index of the char after the last one in the CharSequence appended to the StringWriter.

Returns:

The StringWriter.

Throws:

IndexOutOfBoundsException - If start is less than end, end is greater than the length of the CharSequence, or start or end is negative.