wp456

摘要： package frank;import java.lang.*;import java.util.Collection;import java.util.HashSet;/** * foreach 遍历集合 * */public class App{ public static void main(String[] args)throws Exception { Collection books = new HashSet();//创建集合 books.add(1); books.add(2); books.add(3); for(Object item : books) { ... 阅读全文