2. Objectives
On completion of this period, you would be able to
learn
• Other I/O stream classes
• ByteArrayInputStream
• ByteArrayOutputStream
• BufferedInputStream
• BufferedOutputStream
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3. Recap
In the last class, you have studied about the types
Stream Class
• Byte Streams are two types
1. InputStream class
2. OutputStream class
• FileInputStream and FileOutputStream are the
subclasses of byte stream
• Let us explore some more stream classes
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4. ByteArrayInputStream class
• Data stored in memory is handled by
ByteArrayInputStream
• This class is used to read bytes from a memory
• Objects of this class are used to create input stream
with memory buffers as data source
• Constructors
• ByteArrayInputStream(byte array[ ])
• ByteArrayInputStream(byte array[ ], int start, int
numBytes)
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5. ByteArrayOutputStream class
• Data stored in memory is handled by
ByteArrayOutputStream
• This class is used to write bytes into memory
• Objects of this class are used to create output stream
with memory buffers as data sink
• Constructors
• ByteArrayOutputStream( )
• ByteArrayOutputStream(int numBytes)
• In the first form, a buffer of 32 bytes is created.
• In the second, a buffer is created with a size equal to that
specified by numBytes
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6. Filtered Byte Stream class
• Byte streams access the data in byte form
• Raw bytes can not be used for any useful purpose
• For converting bytes to useful forms such as char,
string, int, etc filtered streams are used
• Streams that can take other stream as arguments are
called filtered streams
• FilterInputStream
• BufferedInputStream is a subclass of it
• FilterOutputStream
• BufferedOutputStream is a subclass of it
In many practical situations only filtered streams are
useful
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7. BufferedInputStream class
• This is a subclass of FilterInpuStream
• This class is used to increase the efficiency of reading
bytes from an input stream
• Fetching a byte and sending it to the destination one
after the another is a time consuming process
• Instead, bytes can be read and stored in buffer
memory before sending it to the destination
• Once the buffer is full, the bytes can be sent to the
destination
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8. BufferedOutputStream class
• This class is a subclass of FilterOutputStream
• This class is used to send buffered bytes to an
underlying output stream in an efficient way
Constructors
• BufferedOutputStream(OutputStream outputStream)
• BufferedOutputStream(OutputStream outputStream, int bufSize)
• The first form creates a buffered stream using a buffer
of 512 bytes. In the second form,
• the size of the buffer is passed in bufSize.
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9. Summary
• Data stored in memory is handled by
ByteArrayInputStream and is used to read bytes
from a memory
• ByteArrayOutputStream is used to write bytes into
memory
• FilteredStreams are used for converting bytes to
useful forms such as char, string, int, etc
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10. Quiz
1. ---- is used to read bytes from a memory
A. ByteArrayOutputStream
B. ByteArrayInputStream
C. Reader
D. None
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11. Quiz
2. --- is used to write bytes into memory
A. ByteArrayInputStream
B. ByteArrayOutputStream
C. Writer
D. None
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12. Frequently Asked Questions
1. Write about ByteArrayInput and ByteArrayOutput
streams
2. Write about FilteredByte Streams
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