{"id":134047,"date":"2020-07-21T05:11:02","date_gmt":"2020-07-20T21:11:02","guid":{"rendered":"http:\/\/4563.org\/?p=134047"},"modified":"2020-07-21T05:11:02","modified_gmt":"2020-07-20T21:11:02","slug":"scala%e8%af%ad%e8%a8%80%e5%ad%a6%e4%b9%a0%ef%bc%88%e5%8d%81%ef%bc%89%e3%80%81%e6%b3%9b%e5%9e%8b%e3%80%81%e4%b8%8a%e4%b8%8b%e7%95%8c","status":"publish","type":"post","link":"http:\/\/4563.org\/?p=134047","title":{"rendered":"scala\u8bed\u8a00\u5b66\u4e60\uff08\u5341\uff09\u3001\u6cdb\u578b\u3001\u4e0a\u4e0b\u754c"},"content":{"rendered":"

<\/a>\u6cdb\u578b<\/h2>\n

scala\u548cJava\u4e00\u6837\uff0c\u7c7b\u548c\u7279\u8d28\u3001\u65b9\u6cd5\u90fd\u53ef\u4ee5\u652f\u6301\u6cdb\u578b\u3002\u6211\u4eec\u5728\u5b66\u4e60\u96c6\u5408\u7684\u65f6\u5019\uff0c\u4e00\u822c\u90fd\u4f1a\u6d89\u53ca\u5230\u6cdb\u578b\u3002\u5728scala\u4e2d\uff0c\u4f7f\u7528\u65b9\u62ec\u53f7\u6765\u5b9a\u4e49\u7c7b\u578b\u53c2\u6570\u3002<\/p>\n

\n\n\n
\n
1<\/span>
2<\/span>
<\/pre>\n<\/td>\n
\n
scala> val<\/span> list1:List<\/span>[String<\/span>] = List<\/span>(\"1\"<\/span>, \"2\"<\/span>, \"3\"<\/span>)<\/span>
list1: List<\/span>[String<\/span>] = List<\/span>(1<\/span>, 2<\/span>, 3<\/span>)<\/span>
<\/pre>\n<\/td>\n<\/tr>\n<\/table>\n<\/figure>\n
<\/a>\u5b9a\u4e49\u4e00\u4e2a\u6cdb\u578b\u65b9\u6cd5<\/h3>\n
<\/a>\u4e0d\u8003\u8651\u6cdb\u578b\u652f\u6301<\/h4>\n
\n\n\n
\n
1<\/span>
2<\/span>
3<\/span>
4<\/span>
5<\/span>
6<\/span>
7<\/span>
<\/pre>\n<\/td>\n
\n
def<\/span> getMiddle<\/span><\/span>(arr:Array<\/span>[Int<\/span>]) = arr(arr.length \/ 2<\/span>)<\/span>
<\/span>
 def<\/span> main<\/span><\/span>(args: Array<\/span>[String<\/span>]): Unit<\/span> = {<\/span>
   val<\/span> arr1 = Array<\/span>(1<\/span>,2<\/span>,3<\/span>,4<\/span>,5<\/span>)<\/span>
<\/span>
   println(getMiddle(arr1))<\/span>
 }<\/span>
<\/pre>\n<\/td>\n<\/tr>\n<\/table>\n<\/figure>\n
<\/a>\u8003\u8651\u6cdb\u578b\u652f\u6301<\/h4>\n
\n\n\n
\n
1<\/span>
2<\/span>
3<\/span>
4<\/span>
5<\/span>
6<\/span>
7<\/span>
8<\/span>
9<\/span>
10<\/span>
11<\/span>
12<\/span>
13<\/span>
14<\/span>
<\/pre>\n<\/td>\n
\n
<\/span>
def<\/span> getMiddle<\/span><\/span>[A<\/span>](arr:Array<\/span>[A<\/span>]) = arr(arr.length \/ 2<\/span>)<\/span>
<\/span>
  def<\/span> main<\/span><\/span>(args: Array<\/span>[String<\/span>]): Unit<\/span> = {<\/span>
    val<\/span> arr1 = Array<\/span>(1<\/span>,2<\/span>,3<\/span>,4<\/span>,5<\/span>)<\/span>
    val<\/span> arr2 = Array<\/span>(\"a\"<\/span>, \"b\"<\/span>, \"c\"<\/span>, \"d\"<\/span>, \"f\"<\/span>)<\/span>
<\/span>
    println(getMiddle[Int<\/span>](arr1))<\/span>
    println(getMiddle[String<\/span>](arr2))<\/span>
<\/span>
    \/\/ \u7b80\u5199\u65b9\u5f0f<\/span><\/span>
    println(getMiddle(arr1))<\/span>
    println(getMiddle(arr2))<\/span>
  }<\/span>
<\/pre>\n<\/td>\n<\/tr>\n<\/table>\n<\/figure>\n
<\/a>\u5b9a\u4e49\u4e00\u4e2a\u6cdb\u578b\u7c7b<\/h3>\n
\u5b9a\u4e49\u4e00\u4e2aPair\u7c7b\u5305\u542b2\u4e2a\u7c7b\u578b\u4e0d\u56fa\u5b9a\u7684\u6cdb\u578b.<\/p>\n
\n\n\n
\n
1<\/span>
2<\/span>
3<\/span>
4<\/span>
5<\/span>
6<\/span>
7<\/span>
8<\/span>
9<\/span>
10<\/span>
11<\/span>
12<\/span>
13<\/span>
14<\/span>
<\/pre>\n<\/td>\n
\n
\/\/ \u7c7b\u540d\u540e\u9762\u7684\u65b9\u62ec\u53f7\uff0c\u5c31\u8868\u793a\u8fd9\u4e2a\u7c7b\u53ef\u4ee5\u4f7f\u7528\u4e24\u4e2a\u7c7b\u578b\u3001\u5206\u522b\u662fT\u548cS<\/span><\/span>
\/\/ \u8fd9\u4e2a\u540d\u5b57\u53ef\u4ee5\u4efb\u610f\u53d6<\/span><\/span>
class<\/span> Pair<\/span>[T<\/span>, S<\/span>](val first: T<\/span>, val second: S<\/span><\/span>)<\/span><\/span>
<\/span><\/span>
case<\/span> class<\/span> People<\/span>(var name:String<\/span>, val age:Int<\/span><\/span>)<\/span><\/span>
<\/span><\/span>
object<\/span> Pair<\/span> <\/span>{<\/span>
  def<\/span> main<\/span><\/span>(args: Array<\/span>[String<\/span>]): Unit<\/span> = {<\/span>
<\/span>
  val<\/span> p1 = new<\/span> Pair<\/span>[String<\/span>, Int<\/span>](\"\u5f20\u4e09\"<\/span>, 10<\/span>)<\/span>
  val<\/span> p2 = new<\/span> Pair<\/span>[String<\/span>, String<\/span>](\"\u5f20\u4e09\"<\/span>, \"1988-02-19\"<\/span>)<\/span>
  val<\/span> p3 = new<\/span> Pair<\/span>[People<\/span>, People<\/span>](People<\/span>(\"\u5f20\u4e09\"<\/span>, 20<\/span>), People<\/span>(\"\u674e\u56db\"<\/span>, 30<\/span>))<\/span>
  }<\/span>
}<\/span>
<\/pre>\n<\/td>\n<\/tr>\n<\/table>\n<\/figure>\n
<\/a>\u4e0a\u4e0b\u754c<\/h2>\n
\u5728\u6307\u5b9a\u6cdb\u578b\u7c7b\u578b\u65f6\uff0c\u6709\u65f6\u9700\u8981\u754c\u5b9a\u6cdb\u578b\u7c7b\u578b\u7684\u8303\u56f4\uff0c\u800c\u4e0d\u662f\u63a5\u6536\u4efb\u610f\u7c7b\u578b==\u3002\u6bd4\u5982\uff0c\u8981\u6c42\u67d0\u4e2a\u6cdb\u578b\u7c7b\u578b\uff0c\u5fc5\u987b\u662f\u67d0\u4e2a\u7c7b\u7684\u5b50\u7c7b\uff0c\u8fd9\u6837\u5728\u7a0b\u5e8f\u4e2d\u5c31\u53ef\u4ee5\u653e\u5fc3\u7684\u8c03\u7528\u7236\u7c7b\u7684\u65b9\u6cd5\uff0c\u7a0b\u5e8f\u624d\u80fd\u6b63\u5e38\u7684\u4f7f\u7528\u4e0e\u8fd0\u884c.<\/p>\n
scala\u7684\u4e0a\u4e0b\u8fb9\u754c\u7279\u6027\u5141\u8bb8\u6cdb\u578b\u7c7b\u578b\u662f\u67d0\u4e2a\u7c7b\u7684\u5b50\u7c7b\uff0c\u6216\u8005\u662f\u67d0\u4e2a\u7c7b\u7684\u7236\u7c7b\uff0c<\/p>\n