Package org.apache.jackrabbit.core.data.db

Class DbInputStream

java.lang.Object

java.io.InputStream

java.io.FilterInputStream

org.apache.commons.io.input.ProxyInputStream

org.apache.commons.io.input.AutoCloseInputStream

org.apache.jackrabbit.core.data.db.DbInputStream

All Implemented Interfaces:

Closeable, AutoCloseable

public class DbInputStream
extends AutoCloseInputStream

This class represents an input stream backed by a database. The database objects are only acquired when reading from the stream, and stay open until the stream is closed, fully read, or garbage collected.

This class does not support mark/reset. It is always to be wrapped using a BufferedInputStream.

Method Summary

Modifier and Type	Method	Description
int	available()	Invokes the delegate's available() method.
void	close()	Closes the underlying input stream and replaces the reference to it with a ClosedInputStream instance.
void	mark(int readlimit)	This method does nothing.
boolean	markSupported()	Check whether mark and reset are supported.
int	read()	Invokes the delegate's read() method.
int	read(byte[] b)	Invokes the delegate's read(byte[]) method.
int	read(byte[] b, int off, int len)	Invokes the delegate's read(byte[], int, int) method.
void	reset()	This method does nothing.
long	skip(long n)	Invokes the delegate's skip(long) method.

Methods inherited from class java.io.InputStream

nullInputStream, readAllBytes, readNBytes, readNBytes, transferTo

Methods inherited from class java.lang.Object

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

Method Detail

read

public int read()
         throws IOException

Invokes the delegate's read() method. When the stream is consumed, the database objects held by the instance are closed.

Overrides:

read in class ProxyInputStream

Returns:

the byte read or -1 if the end of stream

Throws:

IOException - if an I/O error occurs

read

public int read(byte[] b)
         throws IOException

Invokes the delegate's read(byte[]) method. When the stream is consumed, the database objects held by the instance are closed.

Overrides:

read in class ProxyInputStream

Parameters:

b - the buffer to read the bytes into

Returns:

the number of bytes read or EOF if the end of stream

Throws:

IOException - if an I/O error occurs

read

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

Invokes the delegate's read(byte[], int, int) method. When the stream is consumed, the database objects held by the instance are closed.

Overrides:

read in class ProxyInputStream

Parameters:

b - the buffer to read the bytes into

off - The start offset

len - The number of bytes to read

Returns:

the number of bytes read or -1 if the end of stream

Throws:

IOException - if an I/O error occurs

close

public void close()
           throws IOException

Closes the underlying input stream and replaces the reference to it with a ClosedInputStream instance.

This method is automatically called by the read methods when the end of input has been reached.

Note that it is safe to call this method any number of times. The original underlying input stream is closed and discarded only once when this method is first called. When the stream is consumed, the database objects held by the instance are closed.

Specified by:

close in interface AutoCloseable

Specified by:

close in interface Closeable

Overrides:

close in class AutoCloseInputStream

Throws:

IOException - if the underlying input stream can not be closed

skip

public long skip(long n)
          throws IOException

Invokes the delegate's skip(long) method.

Overrides:

skip in class ProxyInputStream

Parameters:

n - the number of bytes to skip

Returns:

the actual number of bytes skipped

Throws:

IOException - if an I/O error occurs

available

public int available()
              throws IOException

Invokes the delegate's available() method.

Overrides:

available in class ProxyInputStream

Returns:

the number of available bytes

Throws:

IOException - if an I/O error occurs

mark

public void mark(int readlimit)

This method does nothing.

Overrides:

mark in class ProxyInputStream

Parameters:

readlimit - read ahead limit

reset

public void reset()
           throws IOException

This method does nothing.

Overrides:

reset in class ProxyInputStream

Throws:

IOException - if an I/O error occurs

markSupported

public boolean markSupported()

Check whether mark and reset are supported.

Overrides:

markSupported in class ProxyInputStream

Returns:

false