uk.org.ogsadai.common
Class Base64Reader

java.lang.Object
  |
  +--java.io.Reader
        |
        +--uk.org.ogsadai.common.Base64Reader

public class Base64Reader

extends java.io.Reader

A java.io.Reader that wraps a java.io.InputStream and Base64 encodes its contents.

Author:

The OGSA-DAI Project Team

COPYRIGHT_NOTICE

private static final java.lang.String COPYRIGHT_NOTICE

See Also:

Constant Field Values

LOG

private static final DAILogger LOG

BUFFER_SIZE

private static final int BUFFER_SIZE

See Also:

Constant Field Values

mInputStream

private final java.io.InputStream mInputStream

mByteBuffer

private byte[] mByteBuffer

mBase64Data

private char[] mBase64Data

mEncoded

private boolean mEncoded

mRemaining

private int mRemaining

mClosed

private boolean mClosed

Base64Reader

public Base64Reader(java.io.InputStream input)
             throws java.lang.IllegalArgumentException,
                    OutOfMemoryException

Constructs a Base64Reader that wraps the specified InputStream. Data read from the input stream will be Base64 encoded.

Default buffer size is 4096 * 3 bytes.

Parameters:

input - The InputStream to wrap and encode.

Throws:

java.lang.IllegalArgumentException - if input is null.

OutOfMemoryException - if there is no memory available.

read

public int read(char[] cbuf,
                int off,
                int len)
         throws java.io.IOException,
                java.lang.IllegalArgumentException

Read Base64 encoded characters into a portion of an array. This method will block until some input is available, an I/O error occurs, or the end of the stream is reached.

Specified by:

read in class java.io.Reader

Parameters:

cbuf - Destination buffer. Must be able to hold len.

off - Offset at which to start storing characters. Must be >= 0 and < size of cbuf.

len - Maximum number of characters to read. Must be >= 1 and < size of cbuf - off.

Returns:

The number of characters read, or -1 if the end of the stream has been reached.

Throws:

java.io.IOException - if the reader has already been closed or there is a problem when reading from the InputStream.

java.lang.IllegalArgumentException - if the cbuf is null or if off or len contain unsuitable values.

See Also:

Reader.read(char[], int, int)

readAndEncode

private void readAndEncode()
                    throws java.io.IOException

Reads from the wrapped InputStream into the buffer, then encodes to Base64. Called whenever there is no more encoded data to be read.

Throws:

java.io.IOException - if a problem is encountered in reading the data from the InputStream.

close

public void close()

Specified by:

close in class java.io.Reader

readAll

public java.lang.String readAll()
                         throws java.io.IOException,
                                OutOfMemoryException

Reads and Base64 encodes the entire contents of the InputStream. Note that this method may carry a significant memory overhead because all the input data will be encoded and stored in memory in its entirety.

Returns:

a String containing the Base64 encoded data.

Throws:

java.io.IOException - if the reader has already been closed or there is a problem when reading from the InputStream.

OutOfMemoryException - if there is no memory available.