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} } val point = new Point(10, 20) printPoint def printPoint{ println ("Point x location : " + point.x); println ("Point y location : " + point.y); } When the above code is compiled and executed, it produces the following result: C:/>scalac Test.scala C:/>scala Test Point x location : 10 Point y location : 20 C:/> TUTORIALS POINT Simply Easy Learning
CHAPTER 16 Scala Traits A trait encapsulates method and field definitions, which can then be reused by mixing them into classes. Unlike class inheritance, in which each class must inherit from just one superclass, a class can mix in any number of traits. Traits are used to define object types by specifying the signature of the supported methods. Scala also allows traits to be partially implemented but traits may not have constructor parameters. A trait definition looks just like a class definition except that it uses the keyword trait as follows: trait Equal { def isEqual(x: Any): Boolean def isNotEqual(x: Any): Boolean = !isEqual(x) } This trait consists of two methods isEqual and isNotEqual. Here, we have not given any implementation for isEqual where as another method has its implementation. Child classes extending a trait can give implementation for the unimplemented methods. So a trait is very similar to what we have abstract classes in Java. Below is a complete example to show the concept of traits: trait Equal { def isEqual(x: Any): Boolean def isNotEqual(x: Any): Boolean = !isEqual(x) } class Point(xc: Int, yc: Int) extends Equal { var x: Int = xc var y: Int = yc def isEqual(obj: Any) = obj.isInstanceOf[Point] && obj.asInstanceOf[Point].x == x } object Test { def main(args: Array[String]) { val p1 = new Point(2, 3) val p2 = new Point(2, 4) val p3 = new Point(3, 3) println(p1.isNotEqual(p2)) println(p1.isNotEqual(p3)) println(p1.isNotEqual(2)) TUTORIALS POINT Simply Easy Learning
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Scala Tutorial
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ABOUT THE TUTORIAL Scala Tutorial S
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FLOATING POINT LITERALS ...........
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Scala Strings .....................
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CHAPTER 1 Scala Overview Scala, sho
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CHAPTER 2 Scala Environment Setup T
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$scala -version Scala code runner v
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} * This will print 'Hello World' a
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forSome If implicit import Lazy Mat
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CHAPTER 4 Scala Data Types Scala ha
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Characters must not necessarily be
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Variable Type Inference: When you a
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The access to f in class Sub is OK
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var a = 10; var b = 20; var c = 25;
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} } println("a && b = " + (a&&b) );
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a >>> 15 C:/> Assignment Operators:
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Here, operators with the highest pr
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} If the boolean expression evaluat
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Nested if...else Statement: It is a
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while loop do...while loop for loop
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Flow Diagram: Example: object Test
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When the above code is compiled and
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} } // for loop execution with mult
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Flow Diagram: Example: import scala
Page 49 and 50: Infinite Loop: A loop becomes infin
Page 51 and 52: } } return sum A function, which do
Page 53 and 54: When the above code is compiled and
Page 55 and 56: } When the above code is compiled a
Page 57 and 58: } logWithDateBound("message1" ) log
Page 59 and 60: CHAPTER 12 Scala Strings Consider t
Page 61 and 62: } } var str2 = "Tod"; println("Dot
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Page 65 and 66: CHAPTER 13 Scala Arrays Scala provi
Page 67 and 68: C:/> Multi-Dimensional Arrays: Ther
Page 69 and 70: C:/> Scala Arrays Methods: Followin
Page 71 and 72: Scala Lists Scala Lists are quite s
Page 73 and 74: Creating Uniform Lists: You can use
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Page 77 and 78: var s = Set(1,3,5,7) While defining
Page 79 and 80: C:/> Scala Set Methods: Following a
Page 81 and 82: elements. 38 39 40 41 42 43 44 45 4
Page 83 and 84: use two maps with ++ as method colo
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Page 87 and 88: val t = new Tuple3(1, "hello", Cons
Page 89 and 90: The method will return Some[Person]
Page 91 and 92: 6 7 8 9 10 11 12 13 14 def filter(p
Page 93 and 94: Scala Iterator Methods: Following a
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Page 97 and 98: CHAPTER 15 Scala Classes & Objects
Page 99: } } println ("Point y location : "
Page 103 and 104: CHAPTER 17 Scala Pattern Matching P
Page 105 and 106: } // case class, empty one. case cl
Page 107 and 108: } When the above code is compiled a
Page 109 and 110: [0-9] Match any digit; same as [012
Page 111 and 112: CHAPTER 19 Scala Exception Handling
Page 113 and 114: CHAPTER 20 Scala Extractors An extr
Page 115 and 116: CHAPTER 21 Scala Files I/O Scala is
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