CPIT 305 Advanced Programming

Transcription

1 M. G. Abbas Malik CPIT 305 Advanced Programming Assistant Professor Faculty of Computing and IT University of Jeddah

2 Advanced Programming Course book: Introduction to Java Programming: Comprehensive Edition, 10th Edition, Y. Daniel Liang, Pearson Reference BooK: Java How to Program, 9th Edition, Paul Deitel and Harvey Deitel, Deitel. Discrete Mathematics and its Application, Kenneth H. Rosen, 7th Edition, McGraw-Hill Java Docs: Course Home: 75% attendance is compulsory to sit in the final exam M. G. Abbas Malik, FCIT, UoJ 2

3 Advanced Programming Topics Covered Recursion Revisited Review of Object Oriented Concepts Exception Handling File and Stream Handling Binary I/O Multithreading and Parallel Programming Networking - Socket Programming Java Database Programming M. G. Abbas Malik, FCIT, UoJ 3

4 File, Streams and Chapters: 17 Binary I/O M. G. Abbas Malik, FCIT, UoJ 4

5 File Basics Recall that a file is block structured. What does this mean? What happens when an application opens or closes a file? Every OS has its own EOF character and, for text files, its own EOL character(s). M. G. Abbas Malik, FCIT, UoJ 5

6 Streams Java file I/O involves streams. You write and read data to streams. The purpose of the stream abstraction is to keep program code independent from physical devices. Three stream objects are automatically created for every application: System.in, System.out, and System.err. M. G. Abbas Malik, FCIT, UoJ 6

7 Types of Streams There are 2 kinds of streams byte streams character streams M. G. Abbas Malik, FCIT, UoJ 7

8 Character Streams Character streams create text files. These are files designed to be read with a text editor. Java automatically converts its internal unicode characters to the local machine representation (ASCII). M. G. Abbas Malik, FCIT, UoJ 8

9 Byte Streams Byte streams create binary files. A binary file essentially contains the memory image of the data. That is, it stores bits as they are in memory. Binary files are faster to read and write because no translation need take place. Binary files, however, cannot be read with a text editor. M. G. Abbas Malik, FCIT, UoJ 9

10 I/O Classes Java has 6 classes to support stream I/O File: An object of this class is either a file or a directory. OutputStream: base class for byte output streams InputStream: base class for byte input streams M. G. Abbas Malik, FCIT, UoJ 10

11 I/O Classes Writer: base class for character output streams. Reader: base class for character input streams. RandomAccessFile: provides support for random access to a file. Note that the classes InputStream, OutputStream, Reader, and Writer are abstract classes. M. G. Abbas Malik, FCIT, UoJ 11

12 Text I/O in Java File class Scanner class PrintWriter class M. G. Abbas Malik, FCIT, UoJ 12

13 I/O Streams M. G. Abbas Malik, FCIT, UoJ 13

14 Text Stream Vs. Binary Stream M. G. Abbas Malik, FCIT, UoJ 14

15 Text Stream Vs. Binary Stream Text I/O requires encoding and decoding Binary I/O does not involve encoding or decoding, thus is more efficient than text I/O M. G. Abbas Malik, FCIT, UoJ 15

16 Binary I/O Classes The abstract InputStream is the root class for reading binary data, and the abstract OutputStream is the root class for writing binary data M. G. Abbas Malik, FCIT, UoJ 16

17 Binary I/O java.io.inputstream Abstract Class InputStream is the root for binary input classes M. G. Abbas Malik, FCIT, UoJ 17

18 Binary I/O java.io.outputstream Abstract Class OutputStream is the root for binary output classes M. G. Abbas Malik, FCIT, UoJ 18

19 Binary I/O java.io.fileinputstream This class inherits all method of InputStream class, root class for FileInputStream M. G. Abbas Malik, FCIT, UoJ 19

20 Binary I/O java.io.fileoutputstream This class inherits all method of OutputStream class, root class for FileOutputStream M. G. Abbas Malik, FCIT, UoJ 20

21 Binary I/O Using I/O Methods Almost all the methods in the I/O classes throw java.io.ioexception M. G. Abbas Malik, FCIT, UoJ 21

22 FileStream Example LISTING 17.1 TestFileStream.java 1 import java.io.*; 2 3 public class TestFileStream { 4 public static void main(string[] args) throws IOException { 5 try ( 6 // Create an output stream to the file as TRY-With-Resource 7 FileOutputStream output = new FileOutputStream("temp.dat"); 8 ){ 9 // Output values to the file 10 for (int i = 1; i <= 10; i++) 11 output.write(i); 12 } try ( 15 // Create an input stream for the file as TRY-With-Resource 16 FileInputStream input = new FileInputStream("temp.dat"); 17 ) { 18 // Read values from the file 19 int value; 20 while ((value = input.read())!= -1) 21 System.out.print(value + " "); 22 } 23 } 24} Creating the FileOutStream such that it automatically closed when TRY block ends. Creating the FileInStream such that it automatically closed when TRY block ends. M. G. Abbas Malik, FCIT, UoJ 22

23 File Streams When a stream is no longer needed, always close it using the close() method or automatically close it using a try-with-resource statement Not closing streams may cause data corruption in the output file, or other programming errors M. G. Abbas Malik, FCIT, UoJ 23

24 File Streams The root directory for the file is the classpath directory. For the example in this book, the root directory is c:\book, so the file temp.dat is located at c:\book. If you wish to place temp.dat in a specific directory FileOutputStream output = new FileOutputStream ("directory/temp.dat"); File temp.dat will be stored in the folder directory M. G. Abbas Malik, FCIT, UoJ 24

25 File Streams An instance of FileInputStream can be used as an argument to construct a Scanner An instance of FileOutputStream can be used as an argument to construct a PrintWriter new PrintWriter(new FileOutputStream("temp.txt", true)); If temp.txt does not exist, it is created. If temp.txt already exists, new data are appended to the file. M. G. Abbas Malik, FCIT, UoJ 25

26 File Streams Filter streams are streams that filter bytes for some purpose. The basic byte input stream provides a read method that can be used only for reading bytes The basic byte output stream provides a write method that can be used only for writing bytes If we want to read integers, doubles, or strings, you need a filter class to wrap the byte input stream M. G. Abbas Malik, FCIT, UoJ 26

27 DataInputStream DataInputStream reads bytes from the stream and converts them into appropriate primitive-type values or strings DataInputStream extends FilterInputStream and implements the DataInput interface M. G. Abbas Malik, FCIT, UoJ 27

28 DataInputStream M. G. Abbas Malik, FCIT, UoJ 28

29 DataOutputStream DataOutputStream converts primitive-type values or strings into bytes and outputs the bytes to the stream DataOutputStream extends FilterOutputStream and implements the DataOutput interface M. G. Abbas Malik, FCIT, UoJ 29

30 DataOutputStream M. G. Abbas Malik, FCIT, UoJ 30

31 Data Stream Example LISTING 17.2 TestDataStream.java 1 import java.io.*; 2 3 public class TestDataStream { Writing Data in the File temp.dat 4 public static void main(string[] args) throws IOException { 5 try ( // Create an output stream for file temp.dat 6 DataOutputStream output = 7 new DataOutputStream(new FileOutputStream("temp.dat")); 8 ) { 9 // Write student test scores to the file 10 output.writeutf("john"); 11 output.writedouble(85.5); 12 output.writeutf("jim"); 13 output.writedouble(185.5); 14 output.writeutf("george"); 15 output.writedouble(105.25); 16 } Reading Data from the File temp.dat try ( // Create an input stream for file temp.dat 19 DataInputStream input = 20 new DataInputStream(new FileInputStream("temp.dat")); 21 ) { 22 // Read student test scores from the file 23 System.out.println(input.readUTF() + " " + input.readdouble()); 24 System.out.println(input.readUTF() + " " + input.readdouble()); 25 System.out.println(input.readUTF() + " " + input.readdouble()); 26 } 27 } 28} M. G. Abbas Malik, FCIT, UoJ 31

32 Data Stream Example M. G. Abbas Malik, FCIT, UoJ 32

33 End-of-File If you keep reading data at the end of an InputStream, an EOFException will occur This EOFException exception can be used to detect the end of a file M. G. Abbas Malik, FCIT, UoJ 33

34 End-of-File LISTING 17.3 DetectEndOfFile.java 1 import java.io.*; 2 3 public class DetectEndOfFile { 4 public static void main(string[] args) { 5 try { 6 try (DataOutputStream output = 7 new DataOutputStream(new FileOutputStream("test.dat"))) { 8 output.writedouble(4.5); 9 output.writedouble(43.25); 10 output.writedouble(3.2); 11 } try (DataInputStream input = 14 new DataInputStream(new FileInputStream("test.dat"))) { 15 while (true) 16 System.out.println(input.readDouble()); 17 } 18 } 19 catch (EOFException ex) { 20 System.out.println("All data were read"); 21 } 22 catch (IOException ex) { 23 ex.printstacktrace(); 24 } 25 } 26 } Writing Data in the File test.dat Reading Data from the File test.dat Detecting EoF in the File test.dat M. G. Abbas Malik, FCIT, UoJ 34

35 Buffered Input/Output Streams BufferedInputStream/BufferedOutputStream can be used to speed up input and output by reducing the number of disk reads and writes Using BufferedInputStream, the whole block of data on the disk is read into the buffer in the memory once. The individual data are then delivered to your program from the buffer M. G. Abbas Malik, FCIT, UoJ 35

36 Buffered Input/Output Streams M. G. Abbas Malik, FCIT, UoJ 36

37 BufferedInputStream No New Methods manages a buffer behind the scene and automatically reads/writes data from/to disk on demand If no buffer size is specified, the default size is 512 bytes M. G. Abbas Malik, FCIT, UoJ 37

38 BufferedOutputStream No New Methods manages a buffer behind the scene and automatically reads/writes data from/to disk on demand M. G. Abbas Malik, FCIT, UoJ 38

39 Case Study: Copying Files Self Study Chapter 17: Section 17.5 M. G. Abbas Malik, FCIT, UoJ 39

40 Object I/O ObjectInputStream/ObjectOutputStream classes can be used to read/write serializable objects DataInputStream/DataOutputStream enables you to perform I/O for primitive-type values and strings ObjectInputStream/ObjectOutputStream enables you to perform I/O for objects in addition to primitive-type values and strings M. G. Abbas Malik, FCIT, UoJ 40

41 Object I/O ObjectInputStream/ObjectOutputStream contains all the functions of DataInputStream/ DataOutputStream, we can replace DataInputStream/DataOutputStream completely with ObjectInputStream/ObjectOutputStream M. G. Abbas Malik, FCIT, UoJ 41

42 ObjectInputStream ObjectInputStream extends InputStream and implements ObjectInput and ObjectStreamConstants M. G. Abbas Malik, FCIT, UoJ 42

43 ObjectOutputStream ObjectOutputStream extends OutputStream and implements ObjectOutput and ObjectStreamConstants M. G. Abbas Malik, FCIT, UoJ 43

44 ObjectOutputStream Example LISTING 17.5 TestObjectOutputStream.java 1 import java.io.*; 2 3 public class TestObjectOutputStream { 4 public static void main(string[] args) throws IOException { 5 try ( // Create an output stream for file object.dat 6 ObjectOutputStream output = 7 new ObjectOutputStream(new FileOutputStream("object.dat")); 8 ) { 9 // Write a string, double value, and object to the file 10 output.writeutf("john"); 11 output.writedouble(85.5); 12 output.writeobject(new java.util.date()); 13 } 14 } 15} M. G. Abbas Malik, FCIT, UoJ 44

45 ObjectInputStream Example LISTING 17.6 TestObjectInputStream.java 1 import java.io.*; 2 3 public class TestObjectInputStream { 4 public static void main(string[] args) 5 throws ClassNotFoundException, IOException { 6 try ( // Create an input stream for file object.dat 7 ObjectInputStream input = 8 new ObjectInputStream(new FileInputStream("object.dat")); 9 ) { 10 // Read a string, double value, and object from the file 11 String name = input.readutf(); 12 double score = input.readdouble(); 13 java.util.date date = (java.util.date)(input.readobject()); 14 System.out.println(name + " " + score + " " + date); 15 } 16 } 17} M. G. Abbas Malik, FCIT, UoJ 45

46 Serializable Interface Not every object can be written to an output stream Objects that can be so written are said to be serialisable A serializable object is an instance of the java.io.serializable interface, so the object s class must implement Serializable The Serializable interface is a marker interface Implementing this interface enables the Java serialization mechanism to automate the process of storing objects and arrays M. G. Abbas Malik, FCIT, UoJ 46

47 What s an Array List ArrayList is a class in the standard Java libraries that can hold any type of object an object that can grow and shrink while your program is running (unlike arrays, which have a fixed length once they have been created) In general, an ArrayList serves the same purpose as an array, except that an ArrayList can change length while the program is running ArrayList Slides are adopted from M. G. Abbas Malik, FCIT, UoJ 47

48 The ArrayList Class The class ArrayList is implemented using an array as a private instance variable When this hidden array is full, a new larger hidden array is created and the data is transferred to this new array M. G. Abbas Malik, FCIT, UoJ 48

49 Using the ArrayList Class In order to make use of the ArrayList class, it must first be imported import java.util.arraylist; An ArrayList is created and named in the same way as object of any class, except that you specify the base type as follows: ArrayList<BaseType> alist = n e w A r r a y L i s t < B a s e T y p e > ( ) ; M. G. Abbas Malik, FCIT, UoJ 49

50 Creating an ArrayList An initial capacity can be specified when creating an ArrayList as well The following code creates an ArrayList that stores objects of the base type String with an initial capacity of 20 items ArrayList<String> list = new ArrayList<String>(20); Specifying an initial capacity does not limit the size to which an ArrayList can eventually grow Note that the base type of an ArrayList is specified as a type parameter M. G. Abbas Malik, FCIT, UoJ 50

51 Adding elements to an ArrayList The add method is used to add an element at the end of an ArrayList list.add("something"); The method name add is overloaded There is also a two argument version that allows an item to be added at any currently used index position or at the first unused position M. G. Abbas Malik, FCIT, UoJ 51

52 How many elements? The size method is used to find out how many indices already have elements in the ArrayList int howmany = list.size(); The set method is used to replace any existing element, and the get method is used to access the value of any existing element list.set(index, "something else"); String thing = list.get(index); size is NOT capacity size is the number of elements currently stored in the ArrayList Capacity is the maximum number of elements which can be stored. Capacity will automatically increase as needed M. G. Abbas Malik, FCIT, UoJ 52

53 ArrayList code Example // Note the use of Integer, rather than int public static void main( String[ ] args) { ArrayList<Integer> myints = new ArrayList<Integer>(25); System.out.println( Size of myints = + myints.size()); for (int k = 0; k < 10; k++) myints.add( 3 * k ); myints.set( 6, 44 ); System.out.println( Size of myints = + myints.size()); for (int k = 0; k < myints.size(); k++) System.out.print( myints.get( k ) +, ); } Size of myints = 0 Size of myints = 10 0, 3, 6, 9, 12, 15, 44, 21, 24, 27 M. G. Abbas Malik, FCIT, UoJ 53

54 Methods in the Class ArrayList The tools for manipulating arrays consist only of the square brackets and the instance variable length ArrayLists, however, come with a selection of powerful methods that can do many of the things for which code would have to be written in order to do them using arrays M. G. Abbas Malik, FCIT, UoJ 54

55 Some Methods in the Class ArrayList M. G. Abbas Malik, FCIT, UoJ 55

56 Some Methods in the Class ArrayList M. G. Abbas Malik, FCIT, UoJ 56

57 Some Methods in the Class ArrayList M. G. Abbas Malik, FCIT, UoJ 57

58 Some Methods in the Class ArrayList M. G. Abbas Malik, FCIT, UoJ 58

59 Some Methods in the Class ArrayList M. G. Abbas Malik, FCIT, UoJ 59

60 Some Methods in the Class ArrayList M. G. Abbas Malik, FCIT, UoJ 60

61 Some Methods in the Class ArrayList M. G. Abbas Malik, FCIT, UoJ 61

62 Some Methods in the Class ArrayList M. G. Abbas Malik, FCIT, UoJ 62

63 Some Methods in the Class ArrayList M. G. Abbas Malik, FCIT, UoJ 63

64 Some Methods in the Class ArrayList M. G. Abbas Malik, FCIT, UoJ 64

65 Some Methods in the Class ArrayList M. G. Abbas Malik, FCIT, UoJ 65

66 More example code // Note the use of Integer instead of int public static void main( String[ ] args) { ArrayList<Integer> myints = new ArrayList<Integer>(25); System.out.println( Size of myints = + myints.size()); for (int k = 0; k < 10; k++) myints.add( 3 * k ); myints.set( 6, 44 ); myints.add( 4, 42 ); myints.remove( new Integer(99) ); System.out.println( Size of myints = + myints.size()); for (int k = 0; k < myints.size(); k++) System.out.print( myints.get( k ) +, ); if (myints.contains( 57 ) ) System.out.println( 57 found ); System.out.println ( 44 found at index + myints.indexof(44)); } M. G. Abbas Malik, FCIT, UoJ 66

67 Why are Some Parameters of Type Base_Type and Others of type Object When looking at the methods available in the ArrayList class, there appears to be some inconsistency In some cases, when a parameter is naturally an object of the base type, the parameter type is the base type However, in other cases, it is the type Object This is because the ArrayList class implements a number of interfaces, and inherits methods from various ancestor classes These interfaces and ancestor classes specify that certain parameters have type Object M. G. Abbas Malik, FCIT, UoJ 67

68 The "For Each" Loop The ArrayList class is an example of a collection class Starting with version 5.0, Java has added a new kind of for loop called a for-each or enhanced for loop This kind of loop has been designed to cycle through all the elements in a collection (like an ArrayList) M. G. Abbas Malik, FCIT, UoJ 68

69 for-each example public class ForEach { public static void main(string[ ] args) { ArrayList<Integer> list = new ArrayList<Integer>; list.add( 42 ); list.add( 57 ); list.add( 86 ); // for each Integer, i, in list for( Integer i : list ) System.out.println( i ); } } //-- Output M. G. Abbas Malik, FCIT, UoJ 69

70 Copying an ArrayList // create an ArrayList of Integers ArrayList<Integer> a = new ArrayList<Integer>( ); a.add(42); a.add(57); a.add(86); Assignment doesn t work As we ve seen with any object, using assignment just makes two variables refer to the same ArrayList. ArrayList<Integer> b = a; a b Stack Heap M. G. Abbas Malik, FCIT, UoJ 70

71 Copying an ArrayList ArrayList s clone( ) method makes a shallow copy ArrayList<Integer> b = a.clone( ); a b Stack Heap M. G. Abbas Malik, FCIT, UoJ 71

72 Copying an ArrayList We need to manually make a deep copy ArrayList<Integer> b = a.clone( ); for( int k = 0; k < b.size( ); k++) b.set(k, a.get(k)); a b Stack Heap M. G. Abbas Malik, FCIT, UoJ 72

73 ArrayList vs Array Why use an array instead of an ArrayList 1. An ArrayList is less efficient than an array 2. ArrayList does not have the convenient square bracket notation 3. The base type of an ArrayList must be a class type (or other reference type). It cannot be a primitive type. (Although wrappers, auto boxing, and auto unboxing make this a non-issue with Java 5) M. G. Abbas Malik, FCIT, UoJ 73

74 ArrayList vs Array Why use an ArrayList instead of an array? 1. Arrays can t grow. Their size is fixed at compile time. ArrayList grows and shrinks as needed while your program is running 2. You need to keep track of the actual number of elements in your array (recall partially filled arrays). ArrayList will do that for you. 3. Arrays have no methods (just length instance variable) ArrayList has powerful methods for manipulating the objects within it M. G. Abbas Malik, FCIT, UoJ 74

75 The Vector Class The Java standard libraries have a class named Vector that behaves almost exactly the same as the class ArrayList In most situations, either class could be used, however the ArrayList class is newer (Java 5), and is becoming the preferred class M. G. Abbas Malik, FCIT, UoJ 75

76 Serializable Objects Suppose you wish to store an ArrayList object To do this you need to store all the elements in the list Each element is an object that may contain other objects Fortunately, you don t have to go through it manually M. G. Abbas Malik, FCIT, UoJ 76

77 Serializable Objects Java provides a built-in mechanism to automate the process of writing objects Process is referred as object serialization, which is implemented in ObjectOutputStream In contrast, the process of reading objects is referred as object deserialization, which is implemented in ObjectInputStream M. G. Abbas Malik, FCIT, UoJ 77

78 Serializable Objects Many classes in the Java API implement Serializable All the wrapper classes for primitive type values, java.math.biginteger, java.math.bigdecimal, java.lang.string, java.lang.stringbuilder, java.lang.stringbuffer, java.util.date, and java.util.arraylist implement java.io.serializable Attempting to store an object that does not support the Serializable interface would cause a NotSerializableException M. G. Abbas Malik, FCIT, UoJ 78

79 Serializing Arrays An array is serializable if all its elements are serializable An entire array can be saved into a file using writeobject and later can be restored using readobject M. G. Abbas Malik, FCIT, UoJ 79

80 Serializing Arrays LISTING 17.7 TestObjectStreamForArray.java 1 import java.io.*; 2 public class TestObjectStreamForArray { 3 public static void main(string[] args) 4 throws ClassNotFoundException, IOException { 5 int[] numbers = {1, 2, 3, 4, 5}; 6 String[] strings = {"John", "Susan", "Kim"}; 7 try ( // Create an output stream for file array.dat 8 ObjectOutputStream output = new ObjectOutputStream(new 9 FileOutputStream("array.dat", true)); 10 ) { 11 // Write arrays to the object output stream 12 output.writeobject(numbers); 13 output.writeobject(strings); 14 } 15 try ( // Create an input stream for file array.dat 16 ObjectInputStream input = 17 new ObjectInputStream(new FileInputStream("array.dat")); 18 ) { 19 int[] newnumbers = (int[])(input.readobject()); 20 String[] newstrings = (String[])(input.readObject()); 21 // Display arrays 22 for (int i = 0; i < newnumbers.length; i++) 23 System.out.print(newNumbers[i] + " "); 24 System.out.println(); 25 for (int i = 0; i < newstrings.length; i++) 26 System.out.print(newStrings[i] + " "); 27 } 28 } 29} M. G. Abbas Malik, FCIT, UoJ 80

81 Random Access Files All of thestreams you have used so far are known as read-only or write-only streams. These streams are called sequential streams A file that is opened using a sequential stream is called a sequential-access file Java provides the RandomAccessFile class to allow data to be read from and written to at any locations in the file M. G. Abbas Malik, FCIT, UoJ 81

82 Random Access Files Java provides the RandomAccessFile class to allow data to be read from and written to at any locations in the file A file that is opened using the RandomAccessFile class is known as a random-access file The RandomAccessFile class implements the DataInput and DataOutput interfaces M. G. Abbas Malik, FCIT, UoJ 82

83 Random Access Files M. G. Abbas Malik, FCIT, UoJ 83

84 Random Access Files A random-access file consists of a sequence of bytes A special marker called a file pointer is positioned at one of these bytes A read or write operation takes place at the location of the file pointer When a file is opened, the file pointer is set at the beginning of the file M. G. Abbas Malik, FCIT, UoJ 84

85 Random Access Files LISTING 17.8 TestRandomAccessFile.jav 1 import java.io.*; 2 3 public class TestRandomAccessFile { 4 public static void main(string[] args) throws IOException { 5 try ( // Create a random access file 6 RandomAccessFile inout = new RandomAccessFile("inout.dat", "rw"); 7 ) { 8 // Clear the file to destroy the old contents if exists 9 inout.setlength(0); // Write new integers to the file 12 for (int i = 0; i < 200; i++) 13 inout.writeint(i); // Display the current length of the file 16 System.out.println("Current file length is " + inout.length()); // Retrieve the first number 19 inout.seek(0); // Move the file pointer to the beginning 20 System.out.println("The first number is " + inout.readint()); // Retrieve the second number M. G. Abbas Malik, FCIT, UoJ 85

86 Random Access Files 23 inout.seek(1 * 4); // Move the file pointer to the second number 24 System.out.println("The second number is " + inout.readint()); // Retrieve the tenth number 27 inout.seek(9 * 4); // Move the file pointer to the tenth number 28 System.out.println("The tenth number is " + inout.readint()); // Modify the eleventh number 31 inout.writeint(555); // Append a new number 34 inout.seek(inout.length()); // Move the file pointer to the end 35 inout.writeint(999); // Display the new length 38 System.out.println("The new length is " + inout.length()); // Retrieve the new eleventh number 41 inout.seek(10 * 4); // Move the file pointer to the eleventh number 42 System.out.println("The eleventh number is " + inout.readint()); 43 } 44 } 45 } M. G. Abbas Malik, FCIT, UoJ 86

87 Advanced Programming Topics Covered Recursion Revisited Review of Object Oriented Concepts Exception Handling File and Stream Handling Binary I/O Multithreading and Parallel Programming Networking - Socket Programming Java Database Programming M. G. Abbas Malik, FCIT, UoJ 87