Package com.sun.mail.util

Class BASE64DecoderStream

java.lang.Object

java.io.InputStream

java.io.FilterInputStream

com.sun.mail.util.BASE64DecoderStream

All Implemented Interfaces:

Closeable, AutoCloseable

public class BASE64DecoderStream
extends FilterInputStream

This class implements a BASE64 Decoder. It is implemented as a FilterInputStream, so one can just wrap this class around any input stream and read bytes from this filter. The decoding is done as the bytes are read out.

Author:

John Mani, Bill Shannon

Field Summary

Fields inherited from class java.io.FilterInputStream

in

Constructor Summary

Constructors

Constructor	Description
BASE64DecoderStream(InputStream in)	Create a BASE64 decoder that decodes the specified input stream.
BASE64DecoderStream(InputStream in, boolean ignoreErrors)	Create a BASE64 decoder that decodes the specified input stream.

Method Summary

Modifier and Type	Method	Description
int	available()	Returns the number of bytes that can be read from this input stream without blocking.
static byte[]	decode(byte[] inbuf)	Base64 decode a byte array.
boolean	markSupported()	Tests if this input stream supports marks.
int	read()	Read the next decoded byte from this input stream.
int	read(byte[] buf, int off, int len)	Reads up to len decoded bytes of data from this input stream into an array of bytes.
long	skip(long n)	Skips over and discards n bytes of data from this stream.

Methods inherited from class java.io.FilterInputStream

close, mark, read, reset

Methods inherited from class java.io.InputStream

nullInputStream, readAllBytes, readNBytes, readNBytes, transferTo

Methods inherited from class java.lang.Object

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

Constructor Detail

BASE64DecoderStream

public BASE64DecoderStream(InputStream in)

Create a BASE64 decoder that decodes the specified input stream. The System property mail.mime.base64.ignoreerrors controls whether errors in the encoded data cause an exception or are ignored. The default is false (errors cause exception).

Parameters:

in - the input stream

BASE64DecoderStream

public BASE64DecoderStream(InputStream in,
                           boolean ignoreErrors)

Create a BASE64 decoder that decodes the specified input stream.

Parameters:

in - the input stream

ignoreErrors - ignore errors in encoded data?

Method Detail

read

public int read()
         throws IOException

Read the next decoded byte from this input stream. The byte is returned as an int in the range 0 to 255. If no byte is available because the end of the stream has been reached, the value -1 is returned. This method blocks until input data is available, the end of the stream is detected, or an exception is thrown.

Overrides:

read in class FilterInputStream

Returns:

next byte of data, or -1 if the end of the stream is reached.

Throws:

IOException - if an I/O error occurs.

See Also:

FilterInputStream.in

read

public int read(byte[] buf,
                int off,
                int len)
         throws IOException

Reads up to len decoded bytes of data from this input stream into an array of bytes. This method blocks until some input is available.

Overrides:

read in class FilterInputStream

Parameters:

buf - the buffer into which the data is read.

off - the start offset of the data.

len - the maximum number of bytes read.

Returns:

the total number of bytes read into the buffer, or -1 if there is no more data because the end of the stream has been reached.

Throws:

IOException - if an I/O error occurs.

skip

public long skip(long n)
          throws IOException

Skips over and discards n bytes of data from this stream.

Overrides:

skip in class FilterInputStream

Throws:

IOException

markSupported

public boolean markSupported()

Tests if this input stream supports marks. Currently this class does not support marks

Overrides:

markSupported in class FilterInputStream

available

public int available()
              throws IOException

Returns the number of bytes that can be read from this input stream without blocking. However, this figure is only a close approximation in case the original encoded stream contains embedded CRLFs; since the CRLFs are discarded, not decoded

Overrides:

available in class FilterInputStream

Throws:

IOException

decode

public static byte[] decode(byte[] inbuf)

Base64 decode a byte array. No line breaks are allowed. This method is suitable for short strings, such as those in the IMAP AUTHENTICATE protocol, but not to decode the entire content of a MIME part. NOTE: inbuf may only contain valid base64 characters. Whitespace is not ignored.

Parameters:

inbuf - the byte array

Returns:

the decoded byte array