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scala 基本语法_2

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[root@cdh2 test]# scala
Welcome to Scala version 2.9.3 (Java HotSpot(TM) Client VM, Java 1.7.0_67).
Type in expressions to have them evaluated.
Type :help for more information.

scala> val oneHalf = new Rational(1, 2);
<console>:7: error: not found: type Rational
       val oneHalf = new Rational(1, 2);
                         ^

scala> import scala.math._
import scala.math._

scala> val oneHalf = new Rational(1, 2);
<console>:10: error: not found: type Rational
       val oneHalf = new Rational(1, 2);
                         ^

scala> val pair = (99, "Luftballons")
pair: (Int, java.lang.String) = (99,Luftballons)

scala> println(pair._1)
99

scala> println(pair._2)
Luftballons

scala> [root@cdh2 test]# 
[root@cdh2 test]# scala Ration.scala
Exception in thread "main" java.lang.RuntimeException: Cannot figure out how to run target: Ration.scala
	at scala.sys.package$.error(package.scala:27)
	at scala.tools.nsc.GenericRunnerCommand.scala$tools$nsc$GenericRunnerCommand$$guessHowToRun(GenericRunnerCommand.scala:38)
	at scala.tools.nsc.GenericRunnerCommand$$anonfun$2.apply(GenericRunnerCommand.scala:48)
	at scala.tools.nsc.GenericRunnerCommand$$anonfun$2.apply(GenericRunnerCommand.scala:48)
	at scala.Option.getOrElse(Option.scala:108)
	at scala.tools.nsc.GenericRunnerCommand.<init>(GenericRunnerCommand.scala:48)
	at scala.tools.nsc.GenericRunnerCommand.<init>(GenericRunnerCommand.scala:17)
	at scala.tools.nsc.MainGenericRunner.process(MainGenericRunner.scala:33)
	at scala.tools.nsc.MainGenericRunner$.main(MainGenericRunner.scala:89)
	at scala.tools.nsc.MainGenericRunner.main(MainGenericRunner.scala)
[root@cdh2 test]# vim Ration.scala
[root@cdh2 test]# scalac Ration.scala
[root@cdh2 test]# scala Ration.scala
[root@cdh2 test]# scala
Welcome to Scala version 2.9.3 (Java HotSpot(TM) Client VM, Java 1.7.0_67).
Type in expressions to have them evaluated.
Type :help for more information.

scala> val oneHalf = new Rational(1, 2);
Created 1/2
oneHalf: Rational = Rational@14bf659

scala> [root@cdh2 test]# 
[root@cdh2 test]# cat Ration.scala
class Rational(n: Int, d: Int) {
 println("Created "+n+"/"+d) 
}
[root@cdh2 test]# vim Rational.scala
[root@cdh2 test]# scalac Ration.scala
[root@cdh2 test]# scala
Welcome to Scala version 2.9.3 (Java HotSpot(TM) Client VM, Java 1.7.0_67).
Type in expressions to have them evaluated.
Type :help for more information.

scala> val oneHalf = new Rational(1, 2);
Created 1/2
oneHalf: Rational = Rational@c95759

scala> val x = new Rational(1, 3)
Created 1/3
x: Rational = Rational@d9b603

scala> [root@cdh2 test]# 
[root@cdh2 test]# scalac Rational.scala
[root@cdh2 test]# scala
Welcome to Scala version 2.9.3 (Java HotSpot(TM) Client VM, Java 1.7.0_67).
Type in expressions to have them evaluated.
Type :help for more information.

scala> val x = new Rational(1, 3)
x: Rational = 1/3

scala> val oneHalf = new Rational(1, 2);
oneHalf: Rational = 1/2

scala> [root@cdh2 test]# 
[root@cdh2 test]# cat Rational.scala
class Rational(n: Int, d: Int) { 
 override def toString = n +"/"+ d 
}
[root@cdh2 test]# cat Ration.scala
class Rational(n: Int, d: Int) {
 println("Created "+n+"/"+d) 
}
[root@cdh2 test]# scala
Welcome to Scala version 2.9.3 (Java HotSpot(TM) Client VM, Java 1.7.0_67).
Type in expressions to have them evaluated.
Type :help for more information.

scala> new Rational(1, 2)
res0: Rational = 1/2

scala> val oneHalf = new Rational(1, 2);
oneHalf: Rational = 1/2

scala> 
这个最初的Rational例子凸显了Java和Scala之间的不同。Java类具有可以带参数的构造器,而Scala类可以直接带参数。
Scala的写法更简洁——类参数可以直接在类的主体中使用;没必要定义字段然后写赋值函数把构造器的参数复制到字段里。
这可以潜在地节省很多固定写法,尤其是对小类来说。 Scala编译器将把你放在类内部的任何不是字段的部分或者方法定义的代码,
编译进主构造器。例如,你可以像这样打印输出一条除错消息: 
class Rational(n: Int, d: Int) { 
  println("Created "+n+"/"+d) 
} 根据这个代码,Scala编译器将把println调用放在Rational的主构造器。
因此,println调用将在每次创建一个新的Rational实例时打印这条除错信息。



scala> new Rational(5, 0)
res1: Rational = 5/0

scala> 除数为零并没有报错。
[root@cdh2 test]# 
[root@cdh2 test]# vim Rational.scala
[root@cdh2 test]# scala Rational.scala
/user/local/test/Rational.scala:2: error: not found: value requre
 requre(d!=0)
 ^
one error found
[root@cdh2 test]# vim Rational.scala
[root@cdh2 test]# scala Rational.scala
[root@cdh2 test]# scalac Rational.scala
[root@cdh2 test]# scala
Welcome to Scala version 2.9.3 (Java HotSpot(TM) Client VM, Java 1.7.0_67).
Type in expressions to have them evaluated.
Type :help for more information.

scala> new Rational(5, 0)
java.lang.IllegalArgumentException: requirement failed
	at scala.Predef$.require(Predef.scala:202)
	at Rational.<init>(Rational.scala:2)
	at .<init>(<console>:8)
	at .<clinit>(<console>)
	at .<init>(<console>:11)
	at .<clinit>(<console>)
	at $print(<console>)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:606)
	at scala.tools.nsc.interpreter.IMain$ReadEvalPrint.call(IMain.scala:704)
	at scala.tools.nsc.interpreter.IMain$Request$$anonfun$14.apply(IMain.scala:920)
	at scala.tools.nsc.interpreter.Line$$anonfun$1.apply$mcV$sp(Line.scala:43)
	at scala.tools.nsc.io.package$$anon$2.run(package.scala:25)
	at java.lang.Thread.run(Thread.java:745)

scala>  除数为零报错正常现象。
scala> val oneHalf = new Rational(1, 2);
oneHalf: Rational = 1/2

scala> 



scala> new Rational(5, 0)
res1: Rational = 5/0

scala> [root@cdh2 test]# 
[root@cdh2 test]# vim Rational.scala
[root@cdh2 test]# scala Rational.scala
/user/local/test/Rational.scala:2: error: not found: value requre
 requre(d!=0)
 ^
one error found
[root@cdh2 test]# vim Rational.scala
[root@cdh2 test]# scala Rational.scala
[root@cdh2 test]# scalac Rational.scala
[root@cdh2 test]# scala
Welcome to Scala version 2.9.3 (Java HotSpot(TM) Client VM, Java 1.7.0_67).
Type in expressions to have them evaluated.
Type :help for more information.

scala> new Rational(5, 0)
java.lang.IllegalArgumentException: requirement failed
	at scala.Predef$.require(Predef.scala:202)
	at Rational.<init>(Rational.scala:2)
	at .<init>(<console>:8)
	at .<clinit>(<console>)
	at .<init>(<console>:11)
	at .<clinit>(<console>)
	at $print(<console>)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:606)
	at scala.tools.nsc.interpreter.IMain$ReadEvalPrint.call(IMain.scala:704)
	at scala.tools.nsc.interpreter.IMain$Request$$anonfun$14.apply(IMain.scala:920)
	at scala.tools.nsc.interpreter.Line$$anonfun$1.apply$mcV$sp(Line.scala:43)
	at scala.tools.nsc.io.package$$anon$2.run(package.scala:25)
	at java.lang.Thread.run(Thread.java:745)


scala> val oneHalf = new Rational(1, 2);
oneHalf: Rational = 1/2

scala> 

scala> [root@cdh2 test]# 
[root@cdh2 test]# vim Rationa.scala
[root@cdh2 test]# scalac Rationa.scala
Rationa.scala:5: error: value d is not a member of Rational
  new Rational(n * that.d + that.n * d, d * that.d) 
                        ^
Rationa.scala:5: error: value d is not a member of Rational
  new Rational(n * that.d + that.n * d, d * that.d) 
                                                 ^
two errors found
[root@cdh2 test]# cat Rationa.scala
class Rational(n: Int, d: Int) { // 编译不过 
  require(d != 0) 
  override def toString = n +"/"+ d 
  def add(that: Rational): Rational = 
  new Rational(n * that.d + that.n * d, d * that.d) 
}
[root@cdh2 test]# vim Rationa_1.scala
[root@cdh2 test]# scala Rationa_1.scala
[root@cdh2 test]# scalac Rationa_1.scala
[root@cdh2 test]# scala
Welcome to Scala version 2.9.3 (Java HotSpot(TM) Client VM, Java 1.7.0_67).
Type in expressions to have them evaluated.
Type :help for more information.

scala> val oneHalf = new Rational(1, 2)
oneHalf: Rational = 1/2

scala> val twoThirds = new Rational(2, 3)
twoThirds: Rational = 2/3

scala> oneHalf add(twoThirds)
res0: Rational = 7/6

scala> [root@cdh2 test]# 
[root@cdh2 test]# cat Rationa_1.scala
class Rational(n: Int, d: Int) { 
  require(d != 0) 
  val numer: Int = n 
  val denom: Int = d 
  override def toString = numer+"/"+denom 
  def add(that: Rational): Rational =
     new Rational( numer * that.denom + that.numer * denom, denom * that.denom ) 
}
[root@cdh2 test]# scala
Welcome to Scala version 2.9.3 (Java HotSpot(TM) Client VM, Java 1.7.0_67).
Type in expressions to have them evaluated.
Type :help for more information.

scala> val five = new Rational(5)
<console>:7: error: not enough arguments for constructor Rational: (n: Int, d: Int)Rational.
Unspecified value parameter d.
       val five = new Rational(5)
                  ^

scala> [root@cdh2 test]# 
[root@cdh2 test]# cp Rationa_1.scala R
RangeArray.scala    Rational.class      Rationa.scala       RegexD1.scala       RegexD.scala        RegexTest1.scala    
Rationa_1.scala     Rational.scala      Ration.scala        RegexD2.scala       RegexReplace.scala  RegexTest2.scala    
[root@cdh2 test]# cp Rationa_1.scala Rationa_2.scala 
[root@cdh2 test]# cat Rationa_1.scala
class Rational(n: Int, d: Int) { 
  require(d != 0) 
  val numer: Int = n 
  val denom: Int = d 
  override def toString = numer+"/"+denom 
  def add(that: Rational): Rational =
     new Rational( numer * that.denom + that.numer * denom, denom * that.denom ) 
}
[root@cdh2 test]# vim Rationa_2.scala
[root@cdh2 test]# scala Rationa_2.scala
/user/local/test/Rationa_2.scala:5: error: value update is not a member of this.Rational
  this(n:Int)=this(n,1)
  ^
one error found
[root@cdh2 test]# vim Rationa_2.scala
[root@cdh2 test]# scalac Rationa_2.scala
[root@cdh2 test]# scala
Welcome to Scala version 2.9.3 (Java HotSpot(TM) Client VM, Java 1.7.0_67).
Type in expressions to have them evaluated.
Type :help for more information.

scala> val five = new Rational(5)
five: Rational = 5/1

scala> five.
add            asInstanceOf   denom          isInstanceOf   numer          toString       

scala> five.denom
res0: Int = 1

scala> five.numer
res1: Int = 5

scala> [root@cdh2 test]# 
[root@cdh2 test]# vim Rationa_3.scala

[1]+  Stopped                 vim Rationa_3.scala
[root@cdh2 test]# cp Rationa_2.scala Rationa_3.scala 
[root@cdh2 test]# vim Rationa_3.scala
[root@cdh2 test]# scalac Rationa_3.scala
[root@cdh2 test]# scala
Welcome to Scala version 2.9.3 (Java HotSpot(TM) Client VM, Java 1.7.0_67).
Type in expressions to have them evaluated.
Type :help for more information.

scala> five.denom
<console>:8: error: not found: value five
              five.denom
              ^

scala> val five = new Rational(5)
five: Rational = 5/1

scala> five.denom
res1: Int = 1

scala> val oneHalf = new Rational(1, 2)
oneHalf: Rational = 1/2

scala> val twoThirds = new Rational(2, 3)
twoThirds: Rational = 2/3

scala> oneHalf.max
                                    def max(that: Rational): Rational   

scala> oneHalf.max(twoThirds)
res2: Rational = 2/3

scala> twoThirds.max(oneHalf)
res3: Rational = 2/3

scala> twoThirds.lessThan(oneHalf)
res4: Boolean = false

scala> oneHalf.lessThan(twoThirds)
res5: Boolean = true

scala> [root@cdh2 test]# 
[root@cdh2 test]# cat Rationa_3.scala
class Rational(n: Int, d: Int) { 
  require(d != 0) 
  val numer: Int = n 
  val denom: Int = d 
  def this(n:Int)=this(n,1)
  override def toString = numer+"/"+denom 
  def add(that: Rational): Rational =
     new Rational( numer * that.denom + that.numer * denom, denom * that.denom ) 
  def lessThan(that: Rational) = 
     this.numer * that.denom < that.numer * this.denom // 移项法 this.numer/this.denom  < that.numer/that.denom
  def max(that: Rational) = 
     if (this.lessThan(that)) 
       that 
     else 
       this
}
[root@cdh2 test]# 


[root@cdh2 test]# scala
Welcome to Scala version 2.9.3 (Java HotSpot(TM) Client VM, Java 1.7.0_67).
Type in expressions to have them evaluated.
Type :help for more information.

scala> new Rational(66, 42)
res0: Rational = 66/42

scala> [root@cdh2 test]# 
[root@cdh2 test]# vim Rationa_4.scala 
[root@cdh2 test]# scalac Rationa_4.scala 
[root@cdh2 test]# scala
Welcome to Scala version 2.9.3 (Java HotSpot(TM) Client VM, Java 1.7.0_67).
Type in expressions to have them evaluated.
Type :help for more information.

scala> new Rational(66, 42)
res0: Rational = 11/7

scala> [root@cdh2 test]# 
[root@cdh2 test]# cat Rationa_4.scala 
class Rational(n: Int, d: Int) { 
  require(d != 0) 
  private val g = gcd(n.abs, d.abs) 
  val numer = n / g 
  val denom = d / g 
  def this(n: Int) = this(n, 1) 
  def add(that: Rational): Rational = 
    new Rational( numer * that.denom + that.numer * denom, denom * that.denom ) 
  override def toString = numer+"/"+denom 
  private def gcd(a: Int, b: Int): Int = 
   if (b == 0) 
     a 
   else 
     gcd(b, a % b) 
}

这个版本的Rational里,我们添加了私有字段,g,并修改了numer和denom的初始化器(初始化器:initializer是初始化变量,
例如初始化numer的“n / g”,的代码)。因为g是私有的,它只能在类的主体之内,而不能在外部被访问。我们还添加了一个私有方法,
gcd,用来计算传入的两个Int的最大公约数。比方说,gcd(12, 8)是4。正如你在4.1节中看到的,想让一个字段或方法私有化你只要把
private关键字放在定义的前面。私有的“助手方法”gcd的目的是把类的其它部分,这里是主构造器,需要的代码分离出来。为了确保
g始终是正的,我们传入n和d的绝对值,调用abs即可获得任意整数的绝对值。
Scala编译器将把Rational的三个字段的初始化代码依照它们在源代码中出现的次序放入主构造器。所以g的初始化代码,gcd(n.abs, d.abs),
将在另外两个之前执行,因为它在源文件中出现得最早。g将被初始化为类参数,n和d,的绝对值的最大公约数。然后再被用于numer和denom的初始化。
通过把n和d整除它们的最大公约数,g,每个Rational都将被构造成它的最简形式:
[root@cdh2 test]# scala
Welcome to Scala version 2.9.3 (Java HotSpot(TM) Client VM, Java 1.7.0_67).
Type in expressions to have them evaluated.
Type :help for more information.

scala> 12.abs
res0: Int = 12

scala> -12.abs
res1: Int = 12

scala> (-12).abs
res2: Int = 12

scala> -10.abs
res3: Int = 10

scala> 10.abs
res4: Int = 10

scala> 0.009.abs
res5: Double = 0.009

scala> -0.009.abs
res6: Double = 0.009

scala> 

scala> new Rational(66, 42)
res7: Rational = 11/7

scala> new Rational(40, 10)
res8: Rational = 4/1

scala> new Rational(40, 20)
res9: Rational = 2/1

scala> new Rational(40,0)
java.lang.IllegalArgumentException: requirement failed
	at scala.Predef$.require(Predef.scala:202)
	at Rational.<init>(Rationa_4.scala:2)
	at .<init>(<console>:8)
	at .<clinit>(<console>)
	at .<init>(<console>:11)
	at .<clinit>(<console>)
	at $print(<console>)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:606)
	at scala.tools.nsc.interpreter.IMain$ReadEvalPrint.call(IMain.scala:704)
	at scala.tools.nsc.interpreter.IMain$Request$$anonfun$14.apply(IMain.scala:920)
	at scala.tools.nsc.interpreter.Line$$anonfun$1.apply$mcV$sp(Line.scala:43)
	at scala.tools.nsc.io.package$$anon$2.run(package.scala:25)
	at java.lang.Thread.run(Thread.java:745)


scala> new Rational(40)
res11: Rational = 40/1

scala> 2+3
res12: Int = 5

scala> 2/3+2/4
res13: Int = 0

scala> 2/3 add 2/4
<console>:8: error: value add is not a member of Int
              2/3 add 2/4
                  ^

scala> (2/3).add(2/4)
<console>:8: error: value add is not a member of Int
              (2/3).add(2/4)
                    ^

scala> 2 add 3
<console>:8: error: value add is not a member of Int
              2 add 3
                ^

scala> val oneHalf = new Rational(1, 2)
oneHalf: Rational = 1/2

scala> val twoThirds = new Rational(2, 3)
twoThirds: Rational = 2/3

scala> oneHalf.add(twoThirds)
res17: Rational = 7/6

scala> oneHalf add twoThirds
res18: Rational = 7/6

scala> oneHalf + twoThirds
<console>:10: error: type mismatch;
 found   : Rational
 required: String
              oneHalf + twoThirds
                        ^

scala> [root@cdh2 test]# 
[root@cdh2 test]# vim Rationa_5.scala 
[root@cdh2 test]# scalac Rationa_5.scala 
[root@cdh2 test]# scala
Welcome to Scala version 2.9.3 (Java HotSpot(TM) Client VM, Java 1.7.0_67).
Type in expressions to have them evaluated.
Type :help for more information.

scala> val oneHalf = new Rational(1, 2)
oneHalf: Rational = 1/2

scala> val twoThirds = new Rational(2, 3)
twoThirds: Rational = 2/3

scala> oneHalf + twoThirds
res0: Rational = 7/6

scala> oneHalf *twoThirds
res1: Rational = 1/3

scala> [root@cdh2 test]# 
[root@cdh2 test]# cat Rationa_5.scala 
class Rational(n: Int, d: Int) { 
  require(d != 0) 
  private val g = gcd(n.abs, d.abs) 
  val numer = n / g 
  val denom = d / g 
  def this(n: Int) = this(n, 1) 
  def +(that: Rational): Rational = 
    new Rational( numer * that.denom + that.numer * denom, denom * that.denom ) 
  def *(that: Rational): Rational = 
    new Rational(numer * that.numer, denom * that.denom) 
  override def toString = numer+"/"+denom 
  private def gcd(a: Int, b: Int): Int =
   if (b == 0) 
     a 
   else 
     gcd(b, a % b) }
[root@cdh2 test]# 


[root@cdh2 test]# cat Rationa_5.scala 
class Rational(n: Int, d: Int) { 
  require(d != 0) 
  private val g = gcd(n.abs, d.abs) 
  val numer = n / g 
  val denom = d / g 
  def this(n: Int) = this(n, 1) 
  def +(that: Rational): Rational = 
    new Rational( numer * that.denom + that.numer * denom, denom * that.denom ) 
  def *(that: Rational): Rational = 
    new Rational(numer * that.numer, denom * that.denom) 
  override def toString = numer+"/"+denom 
  private def gcd(a: Int, b: Int): Int =
   if (b == 0) 
     a 
   else 
     gcd(b, a % b) }
[root@cdh2 test]# scala
Welcome to Scala version 2.9.3 (Java HotSpot(TM) Client VM, Java 1.7.0_67).
Type in expressions to have them evaluated.
Type :help for more information.

scala> oneHalf *twoThirds
<console>:8: error: not found: value oneHalf
              oneHalf *twoThirds
              ^

scala> val twoThirds = new Rational(2, 3)
twoThirds: Rational = 2/3

scala> val oneHalf = new Rational(1, 2)
oneHalf: Rational = 1/2

scala> oneHalf *twoThirds
res1: Rational = 1/3

scala> oneHalf + twoThirds
res2: Rational = 7/6

scala> oneHalf .+ twoThirds
<console>:9: error: missing arguments for method + in class Rational;
follow this method with `_' if you want to treat it as a partially applied function
              oneHalf .+ twoThirds
                       ^

scala> oneHalf .+ (twoThirds)
res4: Rational = 7/6

scala> 



scala> val x = new Rational(1, 2)
x: Rational = 1/2

scala> val y = new Rational(2, 3)
y: Rational = 2/3

scala> x.+(y)
res5: Rational = 7/6

scala> x + y
res6: Rational = 7/6

scala> x + x * y
res7: Rational = 5/6

scala> (x + x) * y
res8: Rational = 2/3

scala> x + (x * y)
res9: Rational = 5/6

scala> 
[root@cdh2 test]# ctrl + d 
[root@cdh2 test]# ll
total 280
-rw-r--r-- 1 root root   65 Jul 10 23:59 2qw
-rw-r--r-- 1 root root  946 Jul  8 00:31 AppTest$$anonfun$1.class
-rw-r--r-- 1 root root 1425 Jul  8 00:31 AppTest.class
-rw-r--r-- 1 root root 1956 Jul  8 00:31 AppTest$.class
-rw-r--r-- 1 root root 1137 Jul  8 00:31 AppTest$delayedInit$body.class
-rw-r--r-- 1 root root  161 Jul  8 00:31 AppTest.scala
-rw-r--r-- 1 root root  632 Jul  5 02:15 ArrayTest.scala
drwxr-xr-x 2 root root 4096 Jul  5 00:58 bak
-rw-r--r-- 1 root root  650 Jul  5 04:58 BreakTest1.scala
-rw-r--r-- 1 root root  401 Jul  5 04:56 BreakTest.scala
-rw-r--r-- 1 root root  330 Jul  4 19:45 CaseTest2.scala
-rw-r--r-- 1 root root  354 Jul  4 20:07 CaseTest3.scala
-rw-r--r-- 1 root root  263 Jul  4 19:38 CaseTest.scala
drwxr-xr-x 5 root root 4096 Jul  5 05:29 classes
-rw-r--r-- 1 root root  351 Jul  5 02:27 ConcatArray.scala
-rw-r--r-- 1 root root  239 Jul  5 02:03 ConsoleTes.scala
-rw-r--r-- 1 root root  197 Jul  5 01:51 ConsoleTest.scala
-rw-r--r-- 1 root root  239 Jul  5 05:02 DoWhileTest.scala
-rw-r--r-- 1 root root  238 Jul  5 03:42 Factor.scala
-rw-r--r-- 1 root root  238 Jul  5 03:42 FactorTest.scala
-rw-r--r-- 1 root root  475 Jul  4 23:37 File1.scala
-rw-r--r-- 1 root root  529 Jul  4 23:40 File2.scala
-rw-r--r-- 1 root root  411 Jul  4 23:32 File.scala
-rw-r--r-- 1 root root  189 Jul  5 01:26 FileWR.scala
-rw-r--r-- 1 root root  403 Jul  5 03:37 FormatTest.scala
-rw-r--r-- 1 root root  585 Jul  4 20:15 ForTest.scala
-rw-r--r-- 1 root root  414 Jul  5 03:59 Fun2.scala
-rw-r--r-- 1 root root  388 Jul  5 03:49 Fun.scala
-rw-r--r-- 1 root root  325 Jul  5 05:29 HelloWorld23.scala
-rw-r--r-- 1 root root  104 Jul  4 18:44 HelloWorld2.scala
-rw-r--r-- 1 root root   88 Jul  4 04:18 HelloWorld.scala
-rw-r--r-- 1 root root   86 Jul  5 05:24 Hl.scala
-rw-r--r-- 1 root root  204 Jul  5 05:04 IfTest.scala
-rw-r--r-- 1 root root  438 Jul  5 02:21 MatrixTest.scala
-rw-r--r-- 1 root root  183 Jul  5 04:35 Other.scala
-rw-r--r-- 1 root root  223 Jul  5 04:21 Outer1.scala
-rw-r--r-- 1 root root  169 Jul  5 04:14 Outer.scala
-rwxr-xr-x 1 root root  193 Jul  4 04:06 person.sh
-rw-r--r-- 1 root root  365 Jul  5 04:38 ProtectPub.scala
-rw-r--r-- 1 root root  424 Jul  5 03:25 RangeArray.scala
-rw-r--r-- 1 root root  262 Jul 11 00:44 Rationa_1.scala
-rw-r--r-- 1 root root  290 Jul 11 01:05 Rationa_2.scala
-rw-r--r-- 1 root root  475 Jul 11 01:24 Rationa_3.scala
-rw-r--r-- 1 root root  425 Jul 11 02:11 Rationa_4.scala
-rw-r--r-- 1 root root  516 Jul 11 02:44 Rationa_5.scala
-rw-r--r-- 1 root root 2274 Jul 11 02:44 Rational.class
-rw-r--r-- 1 root root   87 Jul 11 00:19 Rational.scala
-rw-r--r-- 1 root root  200 Jul 11 00:29 Rationa.scala
-rw-r--r-- 1 root root   65 Jul 10 23:59 Ration.scala
-rw-r--r-- 1 root root  234 Jul  4 22:12 RegexD1.scala
-rw-r--r-- 1 root root  250 Jul  4 22:18 RegexD2.scala
-rw-r--r-- 1 root root  349 Jul  4 22:07 RegexD.scala
-rw-r--r-- 1 root root  231 Jul  4 21:54 RegexReplace.scala
-rw-r--r-- 1 root root  270 Jul  4 21:48 RegexTest1.scala
-rw-r--r-- 1 root root  243 Jul  4 20:49 RegexTest2.scala
-rwxr-xr-x 1 root root  166 Jul  4 04:13 script.sh
-rw-r--r-- 1 root root  602 Jul  5 00:00 Some1.scala
-rw-r--r-- 1 root root  633 Jul  5 00:01 Some.scala
-rw-r--r-- 1 root root  205 Jul  5 01:55 SourceTest.scala
-rw-r--r-- 1 root root  435 Jul  5 03:35 Str.scala
-rw-r--r-- 1 root root  111 Jul  5 05:21 Symb.scala
-rw-r--r-- 1 root root  769 Jul  4 19:07 Test2.scala
-rw-r--r-- 1 root root  426 Jul  4 19:13 Test3.scala
-rw-r--r-- 1 root root  408 Jul  5 00:08 TestExtractor.scala
-rw-r--r-- 1 root root  493 Jul  4 19:00 Test.scala
-rw-r--r-- 1 root root   27 Jul  5 01:57 test.txt
-rw-r--r-- 1 root root  815 Jul  4 19:31 TraitTest.scala
-rw-r--r-- 1 root root  238 Jul  5 04:42 While.scala
-rw-r--r-- 1 root root  176 Jul  5 04:46 WhileTest1.scala
-rw-r--r-- 1 root root  238 Jul  5 04:44 WhileTest.scala
[root@cdh2 test]# sc
scala                                   scl_enabled                             scrollkeeper-get-extended-content-list
scala.bat                               sclient                                 scrollkeeper-get-index-from-docpath
scalac                                  scp                                     scrollkeeper-get-toc-from-docpath
scalac.bat                              script                                  scrollkeeper-get-toc-from-id
scaladoc                                scriptreplay                            scrollkeeper-install
scaladoc.bat                            scrollkeeper-config                     scrollkeeper-preinstall
scalap                                  scrollkeeper-extract                    scrollkeeper-rebuilddb
scalap.bat                              scrollkeeper-gen-seriesid               scrollkeeper-uninstall
schemagen                               scrollkeeper-get-cl                     scrollkeeper-update
scl                                     scrollkeeper-get-content-list           scsi_id
[root@cdh2 test]# script.sh
bash: script.sh: command not found
[root@cdh2 test]# ./ script.sh
bash: ./: is a directory
[root@cdh2 test]# sh script.sh
Hello, world! List()
[root@cdh2 test]# Unix和Windows的Scala脚本
[root@cdh2 test]# cat script.sh
#!/bin/sh
exec scala "$0" "$@"
!#
object HelloWorld {
    def main(args: Array[String]) {
      println("Hello, world! " + args.toList)
    }
}
HelloWorld.main(args)
[root@cdh2 test]# cat script.sh  hahahajj
#!/bin/sh
exec scala "$0" "$@"
!#
object HelloWorld {
    def main(args: Array[String]) {
      println("Hello, world! " + args.toList)
    }
}
HelloWorld.main(args)
cat: hahahajj: No such file or directory
[root@cdh2 test]# sh script.sh haha jj hehe hiehie
Hello, world! List(haha, jj, hehe, hiehie)
[root@cdh2 test]# vim shellarg.sh
[root@cdh2 test]# ls -l  shellarg.sh
-rw-r--r-- 1 root root 102 Jul 11 04:19 shellarg.sh
[root@cdh2 test]# chmod a+x shellarg.sh 
[root@cdh2 test]# ls -l  shellarg.sh
-rwxr-xr-x 1 root root 102 Jul 11 04:19 shellarg.sh
[root@cdh2 test]# sh shellarg.sh chmoda+x
shellarg.sh: line 3: syntax error near unexpected token `"Hello, "'
shellarg.sh: line 3: `println("Hello, " + args(0) + "!")'
[root@cdh2 test]# sh shellarg.sh chmoda
shellarg.sh: line 3: syntax error near unexpected token `"Hello, "'
shellarg.sh: line 3: `println("Hello, " + args(0) + "!")'
[root@cdh2 test]# vim shellarg.sh
[root@cdh2 test]# sh shellarg.sh chmoda
error: script file does not close its header with !# or ::!#
one error found
[root@cdh2 test]# cat shellarg.sh
#!/bin/sh 
exec scala "$0" "$@" !
# // 对第一个参数打招呼 
println("Hello, " + args(0) + "!")
[root@cdh2 test]# vim shellarg.sh
[root@cdh2 test]# sh shellarg.sh chmoda
Hello, chmoda!
[root@cdh2 test]# cat shellarg.sh
#!/bin/sh 
exec scala "$0" "$@"
!# 
// 对第一个参数打招呼 
println("Hello, " + args(0) + "!")
[root@cdh2 test]# 
[root@cdh2 test]# pwd
/user/local/test
[root@cdh2 test]# sh shellarg.sh chmoda
Hello, chmoda!
[root@cdh2 test]# sh shellarg.sh chmoda+x hh
Hello, chmoda+x!
[root@cdh2 test]# 

 



scala 基本语法_2

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原文地址:http://blog.csdn.net/hzdxw/article/details/51883422

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