Input & output
- 1. Input Output
- 2. Submitted To : Falguni Roy, Lecturer , IIT, NSTU. Presented By : Fazle Rabbi (ASH1825004M) Al Shahriar Priyo (ASH1825020M) Md. Saifur Rahman (ASH1825031M) Faizul Karim Pathan (ASH1825033M)
- 3. Contents Input /Output Stream FileOutputStreamClass FileInputStreamClass BufferOutputStreamClass BufferInputStreamClass SequenceInputStreamClass FileWriter FileReader Console FilePermission File FileDescriptor PushBackReaderClass StringWriterClass StringReaderClass Serialization Example of Serialization Advantage of Serialization
- 4. INPUT/OUTPUT • Java I/O (Input and Output) is used to process the input and produce the output. • Java uses the concept of a stream to make I/O operation fast. The java.io package contains all the classes required for input and output operations. • We can perform file handling in Java by Java I/O API.
- 5. STREAM A stream is a sequence of data. In Java, a stream is composed of bytes. It's called a stream because it is like a stream of water that continues to flow. In Java, 3 streams are created for us automatically. All these streams are attached with the console. 1) System.out : standard output stream 2) System.in: standard input stream 3) System.err : standard error stream
- 7. FileOutputStream Class • Java FileOutputStream is an output stream used for writing data to a file. • If you have to write primitive values into a file, use FileOutputStream class.You can write byte-oriented as well as character-oriented data through FileOutputStream class.
- 9. Example :
- 10. FileInputStream Class • Java FileInputStream class obtains input bytes from a file . • It is used for reading byte-oriented data (streams of raw bytes) such as image data, audio, video etc. • also read character-stream data.
- 12. Example : • Output : Hi ,I amTrapped in IIT.
- 13. BufferedOutputStream Class • Java BufferedOutputStream class is used for buffering an output stream. • It internally uses buffer to store data. • It adds more efficiency than to write data directly into a stream. • It makes the performance fast.
- 15. Example :
- 16. BufferedInputStream Class • Java BufferedInputStream class is used to read information from stream. It internally uses buffer mechanism to make the performance fast. • The important points about BufferedInputStream are: • When the bytes from the stream are skipped or read, the internal buffer automatically refilled from the contained input stream, many bytes at a time. • When a BufferedInputStream is created, an internal buffer array is created.
- 18. Example :
- 19. SequenceInputStream Class Java SequenceInputStream class is used to read data from multiple streams. It reads data sequentially (one by one). Methods of SequenceInputStream class :
- 20. Example :
- 21. FileWriter Class • Java FileWriter class is used to write character-oriented data to a file. • It is character-oriented class which is used for file handling in java. • FileWriter is useful to create a file writing characters into it.
- 23. Example :
- 24. FileReader • Java FileReader class is used to read data from the file • FileReader is useful to read data in the form of characters from a ‘text’ file. • The java FileReader class works much like the FileInputStream except the FileInputstream reads bytes, whereas the FileReader reads character.
- 25. Methods of FileReader class
- 26. Example :
- 27. Console • The Java Console class is be used to get input from console. • It provides methods to read texts and passwords. • If you read password using Console class, it will not be displayed to the user.
- 29. FilePermission • Java FilePermission class contains the permission related to a directory or file. • All the permissions are related with path. • The path can be of two types: • D:IO-: It indicates that the permission is associated with all sub directories and files recursively. • D:IO*: It indicates that the permission is associated with all directory and files within this directory excluding sub directories.
- 31. File • The File class is an abstract representation of file and directory pathname. • A pathname can be either absolute or relative • The File class have several methods for working with directories and files such as creating new directories or files, deleting and renaming directories or files, listing the contents of a directory etc
- 32. FileDescriptor • FileDescriptor class serves as an handle to the underlying machine- specific structure representing an open file, an open socket, or another source or sink of bytes. • The handle can be err, in or out. • The FileDescriptor class is used to create a FileInputStream or FileOutputStream to contain it.
- 33. PushbackReader Class PushbackReader class is a character stream reader. It is used to pushes back a character into stream and overrides the FilterReader class. Class declaration public class PushbackReader extends FilterReader
- 34. StringWriter Class Java StringWriter class is a character stream that collects output from string buffer, which can be used to construct a string. The StringWriter class inherits the Writer class. Class declaration: public class StringWriter extends Writer
- 35. StringReader Class StringReader class is a character stream with string as a source. It takes an input string and changes it into character stream. It inherits Reader class. Class declaration: public class StringReader extends Reader
- 36. What is Serialization? • Serialization in Java is a mechanism of writing the state of an object into a byte stream. • It is mainly used in Hibernate, RMI, JPA, EJB and JMS technologies. • The reverse operation of serialization is called deserialization
- 37. java.io.Serializable interface • Serializable is an interface • The Cloneable and Remote are also interfaces. • It must be implemented by the class whose object you want to persist.
- 38. Example of implements Serializable interface
- 39. Example of Java Serialization
- 40. Advantages of Java Serialization • It is mainly used to travel object's state on the network • Built into the system:You don't need to rely on third-party tools, libraries, or configuration. • Relatively simple to understand, at least in the beginning. • Every developer knows it (or should). Regardless of whether Java devs approve or disapprove, they are likely to be familiar with serialising Java objects.