Groovy-10.闭包

class Example {
   static void main(String[] args) {
      def clos = {println "Hello World"};
      clos.call();
   } 
}

class Example {     
   static void main(String[] args) {
      def str1 = "Hello";
      def clos = {param -> println "${str1} ${param}"}
      clos.call("World");
        
      // We are now changing the value of the String str1 which is referenced in the closure
      str1 = "Welcome";
      clos.call("World");
   } 
}

class Example { 
   def static Display(clo) {
      // This time the $param parameter gets replaced by the string "Inner"         
      clo.call("Inner");
   } 
    
   static void main(String[] args) {
      def str1 = "Hello";
      def clos = { param -> println "${str1} ${param}" }
      clos.call("World"); // Hello World 
        
      // We are now changing the value of the String str1 which is referenced in  Z      str1 = "Welcome";
      clos.call("World"); // Welcome World 
        
      // Passing our closure to a method
      Example.Display(clos); //Welcome Inner
   } 
}

class Example {
   static void main(String[] args) {
      def lst = [11, 12, 13, 14];
      lst.each {println it}
   } 
}

class Example {
   static void main(String[] args) {
      def mp = ["TopicName" : "Maps", "TopicDescription" : "Methods in Maps"]             
      mp.each {println it}
      mp.each {println "${it.key} maps to: ${it.value}"}
   } 
}

class Example {
   static void main(String[] args) {
      def lst = [1,2,3,4];
      lst.each {println it}
      println("The list will only display those numbers which are divisible by 2")
      lst.each{num -> if(num % 2 == 0) println num}
   } 
}