Class EncryptedInputStream

java.lang.Object
  java.io.InputStream
      java.io.FilterInputStream
          EncryptedInputStream

public class EncryptedInputStream

extends FilterInputStream

Field Summary

private int	blocksize
private byte[]	buf
private boolean	DEBUG
private static int	DEFAULT_BUFFER_SIZE
private int	end
private boolean	HIT_EOF
private Object	key
private static int	KEY_SIZE
private int	pos

Fields inherited from class java.io.FilterInputStream

in

Fields inherited from class java.io.InputStream

Constructor Summary

EncryptedInputStream(InputStream input)
Creates an EncryptedInputStream with the default buffer size

EncryptedInputStream(InputStream input, int bufsize)
Create an EncryptedInputStream with the given input stream and buffer size

Method Summary

int	available() Return number of bytes available to read.
void	close()
private void	ensureOpen() Make sure the stream is still open
private void	fill() Read from the underlying input stream and decrypt the data.
boolean	markSupported() Return true if this stream supports mark and reset.
int	read() Read the next byte of data from the input stream.
int	read(byte[] b, int off, int len) Read up to b.length bytes of data into a byte array.
private Object	readKey() Read the key from the keyfile

Methods inherited from class java.io.FilterInputStream

mark, read, reset, skip

Methods inherited from class java.lang.Object

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

Field Detail

DEFAULT_BUFFER_SIZE

private static final int DEFAULT_BUFFER_SIZE

See Also:

Constant Field Values

KEY_SIZE

private static final int KEY_SIZE

See Also:

Constant Field Values

DEBUG

private final boolean DEBUG

See Also:

Constant Field Values

HIT_EOF

private boolean HIT_EOF

buf

private byte[] buf

pos

private int pos

end

private int end

blocksize

private int blocksize

key

private Object key

Constructor Detail

EncryptedInputStream

public EncryptedInputStream(InputStream input)
                     throws Exception

Creates an EncryptedInputStream with the default buffer size

Parameters:

input - Underlying input stream

EncryptedInputStream

public EncryptedInputStream(InputStream input,
                            int bufsize)
                     throws Exception

Create an EncryptedInputStream with the given input stream and buffer size

Parameters:

input - the underlying input stream

bufsize - the buffer size (in bytes)

Method Detail

fill

private void fill()
           throws IOException

Read from the underlying input stream and decrypt the data. Put the decrypted data into the buffer. any read() call will bump along the pos variable, this should truncate the array to cut off any data before the pos.

Throws:

IOException

readKey

private Object readKey()
                throws Exception

Read the key from the keyfile

Returns:

the key object.

Throws:

Exception

available

public int available()

Return number of bytes available to read. This will only return > 0 if there's more than 16 bytes in the buffer, so it can decrypt data.

Returns:

number of bytes available.

read

public int read()
         throws IOException

Read the next byte of data from the input stream. Returns -1 if the end of the stream has been reached. This method blocks until a byte can be read.

Returns:

the byte read, or -1 if end of stream.

Throws:

IOException

read

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

Read up to b.length bytes of data into a byte array. Like read(), this will block until data is available. - Wrapper around read(byte[], int off, int len)

Parameters:

b - byte array buffer into which the data is read.

Throws:

IOException

ensureOpen

private void ensureOpen()
                 throws IOException

Make sure the stream is still open

Throws:

IOException

markSupported

public boolean markSupported()

Return true if this stream supports mark and reset. This stream does not yet support mark and reset, so it will always return false.

close

public void close()
           throws IOException

Throws:

IOException