java.io

Interface ObjectInput

public interface ObjectInput extends DataInput

This interface extends the DataInput interface to provide a facility to read objects as well as primitive types from a stream. It also has methods that allow input to be done in a manner similar to InputStream

Method Summary
int	available() This method returns the number of bytes that can be read without blocking.
void	close() This method closes the input source
int	read() This method reading a byte of data from a stream.
int	read(byte[] buf) This method reads raw bytes and stores them them a byte array buffer.
int	read(byte[] buf, int offset, int len) This method reads raw bytes and stores them in a byte array buffer `buf` starting at position `offset` into the buffer.
Object	readObject() Reads an object instance and returns it.
long	skip(long numBytes) This method causes the specified number of bytes to be read and discarded.

Method Detail

available

public int available()

This method returns the number of bytes that can be read without blocking.

Returns: The number of bytes available before blocking

Throws: IOException If an error occurs

close

public void close()

This method closes the input source

Throws: IOException If an error occurs

read

public int read()

This method reading a byte of data from a stream. It returns that byte as an int. This method blocks if no data is available to be read.

Returns: The byte of data read

Throws: IOException If an error occurs

read

public int read(byte[] buf)

This method reads raw bytes and stores them them a byte array buffer. Note that this method will block if no data is available. However, it will not necessarily block until it fills the entire buffer. That is, a "short count" is possible.

Parameters: buf The byte array to receive the data read

Returns: The actual number of bytes read or -1 if end of stream

Throws: IOException If an error occurs

read

public int read(byte[] buf, int offset, int len)

This method reads raw bytes and stores them in a byte array buffer buf starting at position offset into the buffer. A maximum of len bytes will be read. Note that this method blocks if no data is available, but will not necessarily block until it can read len bytes of data. That is, a "short count" is possible.

Parameters: buf The byte array to receive the data read offset The offset into buf to start storing data len The maximum number of bytes to read

Returns: The actual number of bytes read or -1 if end of stream

Throws: IOException If an error occurs

readObject

public Object readObject()

Reads an object instance and returns it. If the class for the object being read cannot be found, then a ClassNotFoundException will be thrown.

Returns: The object instance that was read

Throws: ClassNotFoundException If a class for the object cannot be found IOException If any other error occurs

skip

public long skip(long numBytes)

This method causes the specified number of bytes to be read and discarded. It is possible that fewer than the requested number of bytes will actually be skipped.

Parameters: numBytes The number of bytes to skip

Returns: The actual number of bytes skipped

Throws: IOException If an error occurs