Package de.uplanet.util.base64

Class Base64OutputStream

java.lang.Object

java.io.OutputStream

de.uplanet.util.base64.Base64OutputStream

All Implemented Interfaces:

Closeable, Flushable, AutoCloseable

@Scriptable
public final class Base64OutputStream
extends OutputStream

Base64 encoding as described in RFC 2045 section 6.8.

0 A	17 R	34 i	51 z
1 B	18 S	35 j	52 0
2 C	19 T	36 k	53 1
3 D	20 U	37 l	54 2
4 E	21 V	38 m	55 3
5 F	22 W	39 n	56 4
6 G	23 X	40 o	57 5
7 H	24 Y	41 p	58 6
8 I	25 Z	42 q	59 7
9 J	26 a	43 r	60 8
10 K	27 b	44 s	61 9
11 L	28 c	45 t	62 +
12 M	29 d	46 u	63 /
13 N	30 e	47 v
14 O	31 f	48 w	(pad) =
15 P	32 g	49 x
16 Q	33 h	50 y

This stream-based encoding will outperform Base64Encoder when writing data sizes beyond about 400 bytes to a StringWriter provided that the output buffer is properly preallocated using the outputSizeFromInputSize(int) method. In these cases use the following pattern:

byte[] l_data;

// ...

StringWriter l_sw = new StringWriter(Base64OutputStream.outputSizeFromInputSize(l_data.length));
Base64OutputStream l_out = new Base64OutputStream(l_sw);

l_out.write(l_data);
l_out.close();

String l_strEncoded = l_sw.toString();

See Also:

• Base64InputStream

Constructor Summary

Constructors

Constructor	Description
Base64OutputStream(Writer p_out)	Constructor for Base64OutputStream.
Base64OutputStream(XMLStreamWriter p_xmlStreamWriter)	Constructor for Base64OutputStream.

Method Summary

Modifier and Type	Method	Description
void	close()	Close the stream, finish()ing encoding and flush()ing it first.
void	finish()	Finishes writing base64-encoded data to the output stream without closing the underlying stream.
void	flush()	Flush the stream.
static int	outputSizeFromInputSize(int p_iSize)	Calculates the size of the output for the given input size.
void	write(byte[] p_buf)	Writes an array of bytes to the base64-encoded output stream.
void	write(byte[] p_buf, int p_iOffs, int p_iLen)	Writes an array of bytes to the base64-encoded output stream.
void	write(int p_byte)	Writes a single byte to the base64-encoded output stream.

Methods inherited from class java.io.OutputStream

nullOutputStream

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Details

Base64OutputStream

public Base64OutputStream(Writer p_out)

Constructor for Base64OutputStream. Creates a new base64 output stream to write data to the specified underlying output stream with a default 512-byte buffer size.

Parameters:

p_out - The underlying stream.

Base64OutputStream

public Base64OutputStream(XMLStreamWriter p_xmlStreamWriter)

Constructor for Base64OutputStream. Creates a new base64 output stream to write data to the specified XMLStreamWriter with a default 512-byte buffer size.

Parameters:

p_xmlStreamWriter - The p_xmlStreamWriter to write to.

Method Details

outputSizeFromInputSize

public static int outputSizeFromInputSize(int p_iSize)

Calculates the size of the output for the given input size. Note: values obtained for chunks of data are not additive.

Parameters:

p_iSize - The input size in bytes.

Returns:

The output size in characters.

write

public void write(int p_byte)
           throws IOException

Writes a single byte to the base64-encoded output stream.

Specified by:

write in class OutputStream

Parameters:

p_byte - The byte to be written.

Throws:

IOException - If an I/O error occurs.

write

public void write(byte[] p_buf)
           throws IOException

Writes an array of bytes to the base64-encoded output stream.

Overrides:

write in class OutputStream

Parameters:

p_buf - The data to be written.

Throws:

IOException - If an I/O error occurs.

write

public void write(byte[] p_buf,
 int p_iOffs,
 int p_iLen)
           throws IOException

Writes an array of bytes to the base64-encoded output stream.

Overrides:

write in class OutputStream

Parameters:

p_buf - The data to be written.

p_iOffs - The start offset of the data.

p_iLen - The length of the data.

Throws:

IOException - If an I/O error occurs.

finish

public void finish()
            throws IOException

Finishes writing base64-encoded data to the output stream without closing the underlying stream.

Throws:

IOException - If an I/O error occurs.

flush

public void flush()
           throws IOException

Flush the stream. Note: at most two bytes may not be flushed unless finish() is applied.

Specified by:

flush in interface Flushable

Overrides:

flush in class OutputStream

Throws:

IOException - If an I/O error occurs.

close

public void close()
           throws IOException

Close the stream, finish()ing encoding and flush()ing it first.

Specified by:

close in interface AutoCloseable

Specified by:

close in interface Closeable

Overrides:

close in class OutputStream

Throws:

IOException - If an I/O error occurs.