In this section we will discuss the Java IO Object Streams.
Java I/O Object Streams
In this section we will discuss the Java IO Object Streams.
To work with the I/O of objects Java provided the support of Object stream. Object stream classes implements either ObjectInput or the ObjectOutput interfaces. ObjectInput is the subinterface of DataInput and the ObjectOutput is the subinterface of DataOutput interface.
ObjectInput : ObjectInput is an interface which is a subinterface of DataInput interface that facilitate for reading the objects.
Class that implements the ObjectInput interface.
| Class | Description |
| ObjectInputStream | ObjectInputStream retrieves the previously serialized objects. This class can read only those objects which are of type java.io.Serializable or java.io.Externalizable. |
Methods of ObjectInput
- available() : This method is used to find out the
readable number of bytes.
int available() throws IOException - close() : This method is used to close the input stream.
void close() throws IOException - read() : This method is used to read the data's byte.
int read() throws IOException - read(byte[] b) : This method is used to read into an
array of bytes.
int read(byte[] b) throws IOException - read(byte[] b, int off, int len) : This method is used to
read into an array of bytes.
int read(byte[] b, int off, int len) throws IOException - readObject() : This method is used to read the object
that support java.io.Serializable interface and also returns the object.
Object readObject() throws ClassNotFoundException, IOException - skip(long n) : This method is used to skipped over the n
bytes.
long skip(long n) throws IOException
ObjectOutput : ObjectOutput is an interface that extends the DataOutput interface which facilitate to write objects.
Class that implements the ObjectOutput interface.
| Class | Description |
| ObjectOutputStream | This class is used to write the primitive data types and graphs of Java objects into an output stream. This class can write only those objects which support the java.io.Serializable interface, into the output stream. Primitive data types and strings can be written to the output stream using the method of DataOutput interface |
Methods of ObjectOutput
- close() : This method is used to close the output stream.
void close() throws IOException - flush() : This method is used to flushes the output
stream.
void flush() throws IOException - write(byte[] b) : This method is used to write an array of
byte into the output stream.
void write(byte[] b) throws IOException - write(byte[] b, int off, int len) : This method is used
to write an array of byte of the specified length 'len' and started from the
value of 'off', into an output stream.
void write(byte[] b, int off, int len) throws IOException - write(int b) : This method is used to write for the
integer argument to the output stream.
void write(int b) throws IOException - writeObject(Object obj) : This method is used to write
object into the output stream.
void writeObject(Object obj) throws IOException