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diff --git a/fa-ir/java-fa.html.markdown b/fa-ir/java-fa.html.markdown new file mode 100644 index 00000000..cb965fc4 --- /dev/null +++ b/fa-ir/java-fa.html.markdown @@ -0,0 +1,902 @@ +--- +language: java +lang: fa-ir +contributors: + - ["Jake Prather", "https://github.com/JakeHP"] + - ["Jakukyo Friel", "https://weakish.github.io"] + - ["Madison Dickson", "https://github.com/mix3d"] + - ["Simon Morgan", "https://sjm.io/"] + - ["Zachary Ferguson", "https://github.com/zfergus2"] + - ["Cameron Schermerhorn", "https://github.com/cschermerhorn"] + - ["Rachel Stiyer", "https://github.com/rstiyer"] + - ["Michael Dähnert", "https://github.com/JaXt0r"] + - ["Rob Rose", "https://github.com/RobRoseKnows"] + - ["Sean Nam", "https://github.com/seannam"] +translators: + - ["ghaseminya", "https://github.com/ghaseminya"] +filename: LearnJava-fa.java +--- + +جاوا یک زبان برنامه نویسی کامپیوتری چند منظوره، با قابلیت همزمانی، برپایه کلاس و شی گرایی می باشد. +[مطالعه بیشتر.](https://docs.oracle.com/javase/tutorial/java/) + +```java +// Single-line comments start with // + +/* +Multi-line comments look like this. +*/ + +/** + * JavaDoc comments look like this. Used to describe the Class or various + * attributes of a Class. + * Main attributes: + * + * @author @ghaseminya + * @version v1.0 +*/ + +// Import ArrayList class inside of the java.util package +import java.util.ArrayList; +// Import all classes inside of java.security package +import java.security.*; + +// Each .java file contains one outer-level public class, with the same name +// as the file. +public class LearnJava { + + // In order to run a java program, it must have a main method as an entry + // point. + public static void main (String[] args) { + + /////////////////////////////////////// + // Input/Output + /////////////////////////////////////// + + /* + * Output + */ + + // Use System.out.println() to print lines. + System.out.println("Hello World!"); + System.out.println( + "Integer: " + 10 + + " Double: " + 3.14 + + " Boolean: " + true); + + // To print without a newline, use System.out.print(). + System.out.print("Hello "); + System.out.print("World"); + + // Use System.out.printf() for easy formatted printing. + System.out.printf("pi = %.5f", Math.PI); // => pi = 3.14159 + + /* + * Input + */ + + // use Scanner to read input + // must import java.util.Scanner; + Scanner scanner = new Scanner(System.in); + + // read string input + String name = scanner.next(); + + // read byte input + byte numByte = scanner.nextByte(); + + // read int input + int numInt = scanner.nextInt(); + + // read long input + float numFloat - scanner.nextFloat(); + + // read double input + double numDouble = scanner.nextDouble(); + + // read boolean input + boolean bool = scanner.nextBoolean(); + + /////////////////////////////////////// + // Variables + /////////////////////////////////////// + + /* + * Variable Declaration + */ + // Declare a variable using <type> <name> + int fooInt; + // Declare multiple variables of the same + // type <type> <name1>, <name2>, <name3> + int fooInt1, fooInt2, fooInt3; + + /* + * Variable Initialization + */ + + // Initialize a variable using <type> <name> = <val> + int barInt = 1; + // Initialize multiple variables of same type with same + // value <type> <name1>, <name2>, <name3> = <val> + int barInt1, barInt2, barInt3; + barInt1 = barInt2 = barInt3 = 1; + + /* + * Variable types + */ + // Byte - 8-bit signed two's complement integer + // (-128 <= byte <= 127) + byte fooByte = 100; + + // If you would like to interpret a byte as an unsigned integer + // then this simple operation can help + int unsignedIntLessThan256 = 0xff & fooByte; + // this contrasts a cast which can be negative. + int signedInt = (int) fooByte; + + // Short - 16-bit signed two's complement integer + // (-32,768 <= short <= 32,767) + short fooShort = 10000; + + // Integer - 32-bit signed two's complement integer + // (-2,147,483,648 <= int <= 2,147,483,647) + int bazInt = 1; + + // Long - 64-bit signed two's complement integer + // (-9,223,372,036,854,775,808 <= long <= 9,223,372,036,854,775,807) + long fooLong = 100000L; + // L is used to denote that this variable value is of type Long; + // anything without is treated as integer by default. + + // Note: byte, short, int and long are signed. They can have positive and negative values. + // There are no unsigned variants. + // char, however, is 16-bit unsigned. + + // Float - Single-precision 32-bit IEEE 754 Floating Point + // 2^-149 <= float <= (2-2^-23) * 2^127 + float fooFloat = 234.5f; + // f or F is used to denote that this variable value is of type float; + // otherwise it is treated as double. + + // Double - Double-precision 64-bit IEEE 754 Floating Point + // 2^-1074 <= x <= (2-2^-52) * 2^1023 + double fooDouble = 123.4; + + // Boolean - true & false + boolean fooBoolean = true; + boolean barBoolean = false; + + // Char - A single 16-bit Unicode character + char fooChar = 'A'; + + // final variables can't be reassigned to another object, + final int HOURS_I_WORK_PER_WEEK = 9001; + // but they can be initialized later. + final double E; + E = 2.71828; + + // BigInteger - Immutable arbitrary-precision integers + // + // BigInteger is a data type that allows programmers to manipulate + // integers longer than 64-bits. Integers are stored as an array of + // of bytes and are manipulated using functions built into BigInteger + // + // BigInteger can be initialized using an array of bytes or a string. + BigInteger fooBigInteger = new BigInteger(fooByteArray); + + // BigDecimal - Immutable, arbitrary-precision signed decimal number + // + // A BigDecimal takes two parts: an arbitrary precision integer + // unscaled value and a 32-bit integer scale + // + // BigDecimal allows the programmer complete control over decimal + // rounding. It is recommended to use BigDecimal with currency values + // and where exact decimal precision is required. + // + // BigDecimal can be initialized with an int, long, double or String + // or by initializing the unscaled value (BigInteger) and scale (int). + BigDecimal fooBigDecimal = new BigDecimal(fooBigInteger, fooInt); + + // Be wary of the constructor that takes a float or double as + // the inaccuracy of the float/double will be copied in BigDecimal. + // Prefer the String constructor when you need an exact value. + BigDecimal tenCents = new BigDecimal("0.1"); + + // Strings + String fooString = "My String Is Here!"; + + // \n is an escaped character that starts a new line + String barString = "Printing on a new line?\nNo Problem!"; + // \t is an escaped character that adds a tab character + String bazString = "Do you want to add a tab?\tNo Problem!"; + System.out.println(fooString); + System.out.println(barString); + System.out.println(bazString); + + // String Building + // #1 - with plus operator + // That's the basic way to do it (optimized under the hood) + String plusConcatenated = "Strings can " + "be concatenated " + "via + operator."; + System.out.println(plusConcatenated); + // Output: Strings can be concatenated via + operator. + + // #2 - with StringBuilder + // This way doesn't create any intermediate strings. It just stores the string pieces, and ties them together + // when toString() is called. + // Hint: This class is not thread safe. A thread-safe alternative (with some impact on performance) is StringBuffer. + StringBuilder builderConcatenated = new StringBuilder(); + builderConcatenated.append("You "); + builderConcatenated.append("can use "); + builderConcatenated.append("the StringBuilder class."); + System.out.println(builderConcatenated.toString()); // only now is the string built + // Output: You can use the StringBuilder class. + + // StringBuilder is efficient when the fully constructed String is not required until the end of some processing. + StringBuilder stringBuilder = new StringBuilder(); + String inefficientString = ""; + for(int i = 0 ; i < 10; i++){ + stringBuilder.append(i).append(" "); + inefficientString += i + " "; + } + System.out.println(inefficientString); + System.out.println(stringBuilder.toString()); + // inefficientString requires a lot more work to produce, as it generates a String on every loop iteration. + // Simple concatenation with + is compiled to a StringBuilder and toString() + // Avoid string concatenation in loops. + + // #3 - with String formatter + // Another alternative way to create strings. Fast and readable. + String.format("%s may prefer %s.", "Or you", "String.format()"); + // Output: Or you may prefer String.format(). + + // Arrays + // The array size must be decided upon instantiation + // The following formats work for declaring an array + // <datatype>[] <var name> = new <datatype>[<array size>]; + // <datatype> <var name>[] = new <datatype>[<array size>]; + int[] intArray = new int[10]; + String[] stringArray = new String[1]; + boolean boolArray[] = new boolean[100]; + + // Another way to declare & initialize an array + int[] y = {9000, 1000, 1337}; + String names[] = {"Bob", "John", "Fred", "Juan Pedro"}; + boolean bools[] = {true, false, false}; + + // Indexing an array - Accessing an element + System.out.println("intArray @ 0: " + intArray[0]); + + // Arrays are zero-indexed and mutable. + intArray[1] = 1; + System.out.println("intArray @ 1: " + intArray[1]); // => 1 + + // Other data types worth checking out + // ArrayLists - Like arrays except more functionality is offered, and + // the size is mutable. + // LinkedLists - Implementation of doubly-linked list. All of the + // operations perform as could be expected for a + // doubly-linked list. + // Maps - A set of objects that map keys to values. Map is + // an interface and therefore cannot be instantiated. + // The type of keys and values contained in a Map must + // be specified upon instantiation of the implementing + // class. Each key may map to only one corresponding value, + // and each key may appear only once (no duplicates). + // HashMaps - This class uses a hashtable to implement the Map + // interface. This allows the execution time of basic + // operations, such as get and insert element, to remain + // constant even for large sets. + // TreeMap - This class is a sorted tree structure. It implements a red + // black tree and sorts the entries based on the key value or + // the comparator provided while creating the object + + /////////////////////////////////////// + // Operators + /////////////////////////////////////// + System.out.println("\n->Operators"); + + int i1 = 1, i2 = 2; // Shorthand for multiple declarations + + // Arithmetic is straightforward + System.out.println("1+2 = " + (i1 + i2)); // => 3 + System.out.println("2-1 = " + (i2 - i1)); // => 1 + System.out.println("2*1 = " + (i2 * i1)); // => 2 + System.out.println("1/2 = " + (i1 / i2)); // => 0 (int/int returns int) + System.out.println("1/2 = " + (i1 / (double)i2)); // => 0.5 + + // Modulo + System.out.println("11%3 = "+(11 % 3)); // => 2 + + // Comparison operators + System.out.println("3 == 2? " + (3 == 2)); // => false + System.out.println("3 != 2? " + (3 != 2)); // => true + System.out.println("3 > 2? " + (3 > 2)); // => true + System.out.println("3 < 2? " + (3 < 2)); // => false + System.out.println("2 <= 2? " + (2 <= 2)); // => true + System.out.println("2 >= 2? " + (2 >= 2)); // => true + + // Boolean operators + System.out.println("3 > 2 && 2 > 3? " + ((3 > 2) && (2 > 3))); // => false + System.out.println("3 > 2 || 2 > 3? " + ((3 > 2) || (2 > 3))); // => true + System.out.println("!(3 == 2)? " + (!(3 == 2))); // => true + + // Bitwise operators! + /* + ~ Unary bitwise complement + << Signed left shift + >> Signed/Arithmetic right shift + >>> Unsigned/Logical right shift + & Bitwise AND + ^ Bitwise exclusive OR + | Bitwise inclusive OR + */ + + // Increment operators + int i = 0; + System.out.println("\n->Inc/Dec-rementation"); + // The ++ and -- operators increment and decrement by 1 respectively. + // If they are placed before the variable, they increment then return; + // after the variable they return then increment. + System.out.println(i++); // i = 1, prints 0 (post-increment) + System.out.println(++i); // i = 2, prints 2 (pre-increment) + System.out.println(i--); // i = 1, prints 2 (post-decrement) + System.out.println(--i); // i = 0, prints 0 (pre-decrement) + + /////////////////////////////////////// + // Control Structures + /////////////////////////////////////// + System.out.println("\n->Control Structures"); + + // If statements are c-like + int j = 10; + if (j == 10) { + System.out.println("I get printed"); + } else if (j > 10) { + System.out.println("I don't"); + } else { + System.out.println("I also don't"); + } + + // While loop + int fooWhile = 0; + while(fooWhile < 100) { + System.out.println(fooWhile); + // Increment the counter + // Iterated 100 times, fooWhile 0,1,2...99 + fooWhile++; + } + System.out.println("fooWhile Value: " + fooWhile); + + // Do While Loop + int fooDoWhile = 0; + do { + System.out.println(fooDoWhile); + // Increment the counter + // Iterated 99 times, fooDoWhile 0->99 + fooDoWhile++; + } while(fooDoWhile < 100); + System.out.println("fooDoWhile Value: " + fooDoWhile); + + // For Loop + // for loop structure => for(<start_statement>; <conditional>; <step>) + for (int fooFor = 0; fooFor < 10; fooFor++) { + System.out.println(fooFor); + // Iterated 10 times, fooFor 0->9 + } + System.out.println("fooFor Value: " + fooFor); + + // Nested For Loop Exit with Label + outer: + for (int i = 0; i < 10; i++) { + for (int j = 0; j < 10; j++) { + if (i == 5 && j ==5) { + break outer; + // breaks out of outer loop instead of only the inner one + } + } + } + + // For Each Loop + // The for loop is also able to iterate over arrays as well as objects + // that implement the Iterable interface. + int[] fooList = {1, 2, 3, 4, 5, 6, 7, 8, 9}; + // for each loop structure => for (<object> : <iterable>) + // reads as: for each element in the iterable + // note: the object type must match the element type of the iterable. + for (int bar : fooList) { + System.out.println(bar); + //Iterates 9 times and prints 1-9 on new lines + } + + // Switch Case + // A switch works with the byte, short, char, and int data types. + // It also works with enumerated types (discussed in Enum Types), the + // String class, and a few special classes that wrap primitive types: + // Character, Byte, Short, and Integer. + int month = 3; + String monthString; + switch (month) { + case 1: monthString = "January"; + break; + case 2: monthString = "February"; + break; + case 3: monthString = "March"; + break; + default: monthString = "Some other month"; + break; + } + System.out.println("Switch Case Result: " + monthString); + + // Starting in Java 7 and above, switching Strings works like this: + String myAnswer = "maybe"; + switch(myAnswer) { + case "yes": + System.out.println("You answered yes."); + break; + case "no": + System.out.println("You answered no."); + break; + case "maybe": + System.out.println("You answered maybe."); + break; + default: + System.out.println("You answered " + myAnswer); + break; + } + + + // Try-with-resources (Java 7+) + // Try-catch-finally statements work as expected in Java but in Java 7+ + // the try-with-resources statement is also available. Try-with-resources + // simplifies try-catch-finally statements be closing resources + // automatically. + + // In order to use a try-with-resources, include a an instance of a class + // in the try statement. The class must implement java.lang.AutoCloseable. + try(BufferedReader br = new BufferedReader(new FileReader("foo.txt"))) { + // You can attempt to do something that could throw an exception. + System.out.println(br.readLine()); + // In Java 7, the resource will always be closed, even if it throws + // an Exception. + } catch (Exception ex) { + //The resource will be closed before the catch statement executes. + System.out.println("readLine() failed."); + } + // No need for a finally statement in this case, the BufferedReader is + // already closed. This can be used to avoid certain edge cases where + // a finally statement might not be called. + // To learn more: + // https://docs.oracle.com/javase/tutorial/essential/exceptions/tryResourceClose.html + + + // Conditional Shorthand + // You can use the '?' operator for quick assignments or logic forks. + // Reads as "If (statement) is true, use <first value>, otherwise, use + // <second value>" + int foo = 5; + String bar = (foo < 10) ? "A" : "B"; + System.out.println(bar); // Prints A, because the statement is true + + //////////////////////////////////////// + // Converting Data Types And Typecasting + //////////////////////////////////////// + + // Converting data + + // Convert String To Integer + Integer.parseInt("123");//returns an integer version of "123" + + // Convert Integer To String + Integer.toString(123);//returns a string version of 123 + + // For other conversions check out the following classes: + // Double + // Long + // String + + // Typecasting + // You can also cast Java objects, there's a lot of details and deals + // with some more intermediate concepts. Feel free to check it out here: + // https://docs.oracle.com/javase/tutorial/java/IandI/subclasses.html + + /////////////////////////////////////// + // Classes And Functions + /////////////////////////////////////// + + System.out.println("\n->Classes & Functions"); + + // (definition of the Bicycle class follows) + + // Use new to instantiate a class + Bicycle trek = new Bicycle(); + + // Call object methods + trek.speedUp(3); // You should always use setter and getter methods + trek.setCadence(100); + + // toString returns this Object's string representation. + System.out.println("trek info: " + trek.toString()); + + // Double Brace Initialization + // The Java Language has no syntax for how to create static Collections + // in an easy way. Usually you end up in the following way: + private static final Set<String> COUNTRIES = new HashSet<String>(); + static { + COUNTRIES.add("DENMARK"); + COUNTRIES.add("SWEDEN"); + COUNTRIES.add("FINLAND"); + } + + // But there's a nifty way to achieve the same thing in an + // easier way, by using something that is called Double Brace + // Initialization. + private static final Set<String> COUNTRIES = new HashSet<String>() {{ + add("DENMARK"); + add("SWEDEN"); + add("FINLAND"); + }} + + // The first brace is creating a new AnonymousInnerClass and the + // second one declares an instance initializer block. This block + // is called when the anonymous inner class is created. + // This does not only work for Collections, it works for all + // non-final classes. + + } // End main method +} // End LearnJava class + +// You can include other, non-public outer-level classes in a .java file, +// but it is not good practice. Instead split classes into separate files. + +// Class Declaration Syntax: +// <public/private/protected> class <class name> { +// // data fields, constructors, functions all inside. +// // functions are called as methods in Java. +// } + +class Bicycle { + + // Bicycle's Fields/Variables + public int cadence; // Public: Can be accessed from anywhere + private int speed; // Private: Only accessible from within the class + protected int gear; // Protected: Accessible from the class and subclasses + String name; // default: Only accessible from within this package + static String className; // Static class variable + + // Static block + // Java has no implementation of static constructors, but + // has a static block that can be used to initialize class variables + // (static variables). + // This block will be called when the class is loaded. + static { + className = "Bicycle"; + } + + // Constructors are a way of creating classes + // This is a constructor + public Bicycle() { + // You can also call another constructor: + // this(1, 50, 5, "Bontrager"); + gear = 1; + cadence = 50; + speed = 5; + name = "Bontrager"; + } + // This is a constructor that takes arguments + public Bicycle(int startCadence, int startSpeed, int startGear, + String name) { + this.gear = startGear; + this.cadence = startCadence; + this.speed = startSpeed; + this.name = name; + } + + // Method Syntax: + // <public/private/protected> <return type> <function name>(<args>) + + // Java classes often implement getters and setters for their fields + + // Method declaration syntax: + // <access modifier> <return type> <method name>(<args>) + public int getCadence() { + return cadence; + } + + // void methods require no return statement + public void setCadence(int newValue) { + cadence = newValue; + } + public void setGear(int newValue) { + gear = newValue; + } + public void speedUp(int increment) { + speed += increment; + } + public void slowDown(int decrement) { + speed -= decrement; + } + public void setName(String newName) { + name = newName; + } + public String getName() { + return name; + } + + //Method to display the attribute values of this Object. + @Override // Inherited from the Object class. + public String toString() { + return "gear: " + gear + " cadence: " + cadence + " speed: " + speed + + " name: " + name; + } +} // end class Bicycle + +// PennyFarthing is a subclass of Bicycle +class PennyFarthing extends Bicycle { + // (Penny Farthings are those bicycles with the big front wheel. + // They have no gears.) + + public PennyFarthing(int startCadence, int startSpeed) { + // Call the parent constructor with super + super(startCadence, startSpeed, 0, "PennyFarthing"); + } + + // You should mark a method you're overriding with an @annotation. + // To learn more about what annotations are and their purpose check this + // out: http://docs.oracle.com/javase/tutorial/java/annotations/ + @Override + public void setGear(int gear) { + this.gear = 0; + } +} + +// Interfaces +// Interface declaration syntax +// <access-level> interface <interface-name> extends <super-interfaces> { +// // Constants +// // Method declarations +// } + +// Example - Food: +public interface Edible { + public void eat(); // Any class that implements this interface, must + // implement this method. +} + +public interface Digestible { + public void digest(); + // In Java 8, interfaces can have default method. + // public void digest() { + // System.out.println("digesting ..."); + // } +} + +// We can now create a class that implements both of these interfaces. +public class Fruit implements Edible, Digestible { + @Override + public void eat() { + // ... + } + + @Override + public void digest() { + // ... + } +} + +// In Java, you can extend only one class, but you can implement many +// interfaces. For example: +public class ExampleClass extends ExampleClassParent implements InterfaceOne, + InterfaceTwo { + @Override + public void InterfaceOneMethod() { + } + + @Override + public void InterfaceTwoMethod() { + } + +} + +// Abstract Classes + +// Abstract Class declaration syntax +// <access-level> abstract <abstract-class-name> extends <super-abstract-classes> { +// // Constants and variables +// // Method declarations +// } + +// Marking a class as abstract means that it contains abstract methods that +// must be defined in a child class. Similar to interfaces, abstract classes +// cannot be instantiated, but instead must be extended and the abstract +// methods defined. Different from interfaces, abstract classes can contain a +// concrete and abstract methods. Methods in an interface cannot have a body, +// mixture of unless the method is static, and variables are final by default, +// unlike an abstract class. Also abstract classes CAN have the "main" method. +public abstract class Animal +{ + public abstract void makeSound(); + + // Method can have a body + public void eat() + { + System.out.println("I am an animal and I am Eating."); + // Note: We can access private variable here. + age = 30; + } + + // No need to initialize, however in an interface + // a variable is implicitly final and hence has + // to be initialized. + protected int age; + + public void printAge() + { + System.out.println(age); + } + + // Abstract classes can have main function. + public static void main(String[] args) + { + System.out.println("I am abstract"); + } +} + +class Dog extends Animal +{ + // Note still have to override the abstract methods in the + // abstract class. + @Override + public void makeSound() + { + System.out.println("Bark"); + // age = 30; ==> ERROR! age is private to Animal + } + + // NOTE: You will get an error if you used the + // @Override annotation here, since java doesn't allow + // overriding of static methods. + // What is happening here is called METHOD HIDING. + // Check out this SO post: http://stackoverflow.com/questions/16313649/ + public static void main(String[] args) + { + Dog pluto = new Dog(); + pluto.makeSound(); + pluto.eat(); + pluto.printAge(); + } +} + +// Final Classes + +// Final Class declaration syntax +// <access-level> final <final-class-name> { +// // Constants and variables +// // Method declarations +// } + +// Final classes are classes that cannot be inherited from and are therefore a +// final child. In a way, final classes are the opposite of abstract classes +// because abstract classes must be extended, but final classes cannot be +// extended. +public final class SaberToothedCat extends Animal +{ + // Note still have to override the abstract methods in the + // abstract class. + @Override + public void makeSound() + { + System.out.println("Roar"); + } +} + +// Final Methods +public abstract class Mammal() +{ + // Final Method Syntax: + // <access modifier> final <return type> <function name>(<args>) + + // Final methods, like, final classes cannot be overridden by a child + // class, and are therefore the final implementation of the method. + public final boolean isWarmBlooded() + { + return true; + } +} + +// Enum Type +// +// An enum type is a special data type that enables for a variable to be a set +// of predefined constants. The variable must be equal to one of the values +// that have been predefined for it. Because they are constants, the names of +// an enum type's fields are in uppercase letters. In the Java programming +// language, you define an enum type by using the enum keyword. For example, +// you would specify a days-of-the-week enum type as: +public enum Day { + SUNDAY, MONDAY, TUESDAY, WEDNESDAY, + THURSDAY, FRIDAY, SATURDAY +} + +// We can use our enum Day like that: +public class EnumTest { + // Variable Enum + Day day; + + public EnumTest(Day day) { + this.day = day; + } + + public void tellItLikeItIs() { + switch (day) { + case MONDAY: + System.out.println("Mondays are bad."); + break; + case FRIDAY: + System.out.println("Fridays are better."); + break; + case SATURDAY: + case SUNDAY: + System.out.println("Weekends are best."); + break; + default: + System.out.println("Midweek days are so-so."); + break; + } + } + + public static void main(String[] args) { + EnumTest firstDay = new EnumTest(Day.MONDAY); + firstDay.tellItLikeItIs(); // => Mondays are bad. + EnumTest thirdDay = new EnumTest(Day.WEDNESDAY); + thirdDay.tellItLikeItIs(); // => Midweek days are so-so. + } +} + +// Enum types are much more powerful than we show above. +// The enum body can include methods and other fields. +// You can see more at https://docs.oracle.com/javase/tutorial/java/javaOO/enum.html + +``` + +## مطالب بیشتر + +لینکهای زیر را می توانید برای پیگیرهای بیشتر استفاده کنید. +البته همیشه گوگل را در کنار دستتان داشته باشید! + +**سایت های راهنمای اصلی**: + +* [Java Tutorial Trail from Sun / Oracle](https://docs.oracle.com/javase/tutorial/index.html) + +* [Java Access level modifiers](https://docs.oracle.com/javase/tutorial/java/javaOO/accesscontrol.html) + +* [Object-Oriented Programming Concepts](https://docs.oracle.com/javase/tutorial/java/concepts/index.html): + * [Inheritance](https://docs.oracle.com/javase/tutorial/java/IandI/subclasses.html) + * [Polymorphism](https://docs.oracle.com/javase/tutorial/java/IandI/polymorphism.html) + * [Abstraction](https://docs.oracle.com/javase/tutorial/java/IandI/abstract.html) + +* [Exceptions](https://docs.oracle.com/javase/tutorial/essential/exceptions/index.html) + +* [Interfaces](https://docs.oracle.com/javase/tutorial/java/IandI/createinterface.html) + +* [Generics](https://docs.oracle.com/javase/tutorial/java/generics/index.html) + +* [Java Code Conventions](https://www.oracle.com/technetwork/java/codeconvtoc-136057.html) + +* New features in Java 8: + * [Lambda expressions (functional programming)](https://docs.oracle.com/javase/tutorial/java/javaOO/lambdaexpressions.html) + * [Date and time API (java.time package)](http://www.oracle.com/technetwork/articles/java/jf14-date-time-2125367.html) + +**راهنما و سایت های آموزشی** + +* [Learneroo.com - Learn Java](http://www.learneroo.com) + +* [Codingbat.com](http://codingbat.com/java) + +**کتابها**: + +* [Head First Java](http://www.headfirstlabs.com/books/hfjava/) + +* [Thinking in Java](http://www.mindview.net/Books/TIJ/) + +* [Objects First with Java](https://www.amazon.com/Objects-First-Java-Practical-Introduction/dp/0132492660) + +* [Java The Complete Reference](https://www.amazon.com/gp/product/0071606300) |