import java.util.*
import java.util.Collection
public class CollectionTest {
public static void main(String[] args) {
Collection c = new ArrayList()
c.add("guodong")
c.add(54)
c.add(6)
System.out.println("c集合中的元素的个数是:" + c.size())
c.remove(6)
System.out.println("c集合中的元素的个数是:" + c.size())
System.out.println(c.contains( "c中是否包含了guodong " + "guodong"))
Collection books = new HashSet()
books.add("guodong")
System.out.println("c中是否包含了books " + c.contains(books))
System.out.println(books.size())
c.removeAll(books)
System.out.println("c中减去了books中的元素之后剩余元素的个数:" + c.size())
c.clear()
System.out.println("c中清空了之后剩余的元素的个数:" + c.size())
System.out.println("判断是否为空" + c.isEmpty())
}
}