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OBJECT ORIENTED PROGRAMMINGWITH JAVA
SUB CODE: 2720215
1ST YEAR ME (EC)
FACULTY: MAHESH BARGAJE
CONTACT:
https://twitter.com/MaheshBargaje1https://www.facebook.com/mahesh.bargajemailto:[email protected]://in.linkedin.com/pub/mahesh-bargaje/45/812/628/
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SYLLABUS
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UNIT 5: I/O AND APPLETS
STREAMS; FILE I/O; APPLETS; PARAMETERPASSING TO APPLETS
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INTRODUCTION
We have used variables and arrays for storing data.
Problems: Storage is temporary.
Difficulty in handling large volume of data.
Solution: Storing data in terms of FILEs on secondary
storage devices such as: Floppy disks, CDs, Hard disks, etc.
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CONCEPT OF STREAMS
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CONCEPT OF STREAMS
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CONCEPT OF STREAMS
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STREAMS
Streams - is the way we handle I/O.
Why Streams?
Uniformity in handling disparate data.
Stream
Composed of bytes or characters that we can read from or write
to.
Sources and Destinations
Disk file, a memory buffer or a network.
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STREAMS
Package:
Stream I/O is based on following classes:
Byte Oriented Streams
Character- Oriented Streams
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USING FILE CLASS
Package:
This class is used for creation of files and directories, file
searching, file deletion etc.
It describes the Properties of a file.
Directory is also treated as a file.
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CREATING FILES
Constructors:
creates a new File instance by converting the given pathname
string into an abstract pathname.
creates a new File instance from a parent pathname string and a
child pathname string.
creates a new File instance from a parent abstract pathname and
a child pathname string.
creates a new File instance by converting the given file: URI
into an abstract pathname.
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METHODS OF FILE CLASS
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WORKING WITH
Package:
byte-oriented class
Streaming byte input
Throws an
Constructor:
It constructs an InputStream object
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WORKING WITH
Methods of class:
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WORKING WITH
Package:
byte-oriented class
Streaming byte output
Throws an
Constructor:
It constructs an OutputStream object
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WORKING WITH
Methods of class:
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WORKING WITH
Package:
byte-oriented class
Streaming byte output
Throws an
Constructor:
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WORKING WITH
Methods of class:
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WORKING WITH
Methods of class:
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EXERCISE
Write a program that reads from file and prints the
contents.
Whenever it encounters # it should skip reading until next # is
encountered.
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WORKING WITH R
It supports positioning of the file pointer within a file.
Access types are:
r file is read and not written
w- file opened in read-write mode
rws- read write of contents/metadata synchronously to the
storage
rwd- read write of contents synchronously to the storage
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WORKING WITH
Package:
Character-oriented class
Streaming byte output
Throws an
Constructor:
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WORKING WITH
Methods of the class:
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KEYBOARD INPUT: WORKING WITH
Package:
To read keys from the keyboard the source is
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KEYBOARD INPUT: WORKING WITH
Constructors:
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KEYBOARD INPUT: WORKING WITH
Methods of the
class:
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KEYBOARD INPUT: WORKING WITH
Getting input from keyboard:
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KEYBOARD INPUT: SCANNING INPUT WITHCLASS
Getting input from keyboard:
Getting input from a file:
