Groovy語法基礎

• 字符串

task printStringClass <<{
  def str1 = '單引號'
  def str2 = "雙引號"

  println "單引號定義的字符串類型:"+str1.getClass().name;
  println "雙引號定義的字符串類型:"+str2.getClass().name;
}

task printStringVar{
        def name = "張三"
        println '單引號的變量計算:${name}'
        println "雙引號過的變量計算:${name}"
}

 

• • 運行結果

    /gradlew printStringClass
    :printStringClass
    單引號定義的字符串類型:java.lang.String
    雙引號定義的字符串類型:java.lang.String
    
    BUILD SUCCESSFUL
    
    Total time: 2.219 secs
    
    This build could be faster, please consider using the Gradle Daemon: http://gradle.org/docs/2.4/userguide/gradle_daemon.html
    endian11@endian11-virtual-machine:~/lzw/frame/android-gradle-book-code$ vim build.gradle 
    endian11@endian11-virtual-machine:~/lzw/frame/android-gradle-book-code$ ./gradlew printStringVar
    單引號的變量計算:${name}
    雙引號過的變量計算:張三
    :printStringVar UP-TO-DATE
    
    BUILD SUCCESSFUL
    

  • 在Groovy中分號不是必須的
  • 單引號和雙引號均可以定義一個字符串常量

  • 　單引號不能對字符串裏的表達式作運算，雙引號能夠對字符串常量裏面的表達式作運算

• 集合
  • List

    • task printListStr <<{
        def numList = [1,2,3,4,5,6]
        println numList.getClass().name;
        numList.each{
              println it
        }
      }
      

      endian11@endian11-virtual-machine:~/lzw/frame/android-gradle-book-code$ gradle printListStr

      > Task :printListStr
      java.util.ArrayList
      1
      2
      3
      4
      5
      6

      task printMapStr <<{
        def ahashMap = ['width':123,'heigt':456]
        println ahashMap.getClass().name
        println ahashMap["width"]
        println ahashMap.heigt
      
        ahashMap.each{
          println "key:${it.key},Value:${it.value}"
        }
      }
      

      endian11@endian11-virtual-machine:~/lzw/frame/android-gradle-book-code$ gradle printmapstr

      > Task :printMapStr
      java.util.LinkedHashMap
      123
      456
      key:width,Value:123
      key:heigt,Value:456

• 方法
  • 括號是能夠省略的

    task invokeMethod <<{
      method(1,2)
      method 1,2
    }
    
    def method(int a,int b){
      println a+b
    }
    
    

    ./gradlew invokeMethod
    :invokeMethod
    3
    3

  • return是能夠不寫的

    task printMethodReturn << {
      def add1 = method2 1,2
      def add2 = method2 5,3
    
      println "add1:${add1},add2:${add2}"
    }
    
    def method2(int a, int b){
      if (a > b){
       a
            }else{
                    b
            }
    }
    

    endian11@endian11-virtual-machine:~/lzw/frame/android-gradle-book-code$ ./gradlew printMethodReturn
    :printMethodReturn
    add1:2,add2:5

    BUILD SUCCESSFUL

  • 代碼塊是能夠作爲參數被傳遞的
    • 代碼塊是一段被花括號包圍的代碼