分类统计数据
import java.util.ArrayList;import java.util.List;/** * 讲一个list转换成另外一个list * @class Into * @description * @author 李智慧 * @copyRight copyright(c) 2011 广东南航易网通电子商务有限公司,Rights Reserved * @time Nov 10, 2011 3:35:41 PM */public class Into {public static void main(String[] args) {Into into = new Into();List list = into.initList();List list2 = into.changeList(list);into.printMsg(list2);}/** * 初始化对象 * @return */public List initList(){List list = new ArrayList<Student>();/** 十个基本测试的对象学生 **/Student student = new Student(21, "张三", "男");Student student2 = new Student(24, "李四", "男");Student student3 = new Student(23, "王五", "女");Student student4 = new Student(24, "赵六", "女");Student student5 = new Student(26, "韩琦", "男");Student student6 = new Student(21, "尾巴", "男");Student student7 = new Student(29, "哈哈", "男");Student student8 = new Student(23, "弄弄", "女");Student student9 = new Student(24, "章晓", "男");Student student10 = new Student(21, "费力", "女");list.add(student);list.add(student2);list.add(student3);list.add(student4);list.add(student5);list.add(student6);list.add(student7);list.add(student8);list.add(student9);list.add(student10);return list;}/** * 核心方法，转换list，如果年龄一样的话，叠加在一起 * @param list * @return */public List changeList(List list) {List list2 = new ArrayList<Student>();for(int i=0;i<list.size();i++){Student student = (Student) list.get(i);addMsg(list2,student);}return list2;}/** * 加入对应的对象 * @param list * @param student */public static void addMsg(List list,Student student){if(list.size() == 0){//如果是第一个直接加进去list.add(student);}else{for (int i = 0; i < list.size(); i++) {Student student2 = (Student) list.get(i);if(i == list.size()-1){list.add(student);break;}if(student2.getAge() == student.getAge()){if(student.getName().equals(student2.getName())){}else{//已经添加过了的list.remove(i);Student student3 = new Student(student.getAge(),student.getName()+"/"+student2.getName(),student.getSex()+"/"+student2.getSex());list.add(student3);break;}}else{continue;}}}//return list;}/** * 打印出转换后的结果 */public void printMsg(List list){System.out.println("*****分类统计数据*****");for(int i=0;i<list.size();i++){Student student = (Student) list.get(i);System.out.print(student.getAge()+"\t");System.out.print(student.getName()+"\t");System.out.println(student.getSex());}System.out.println("*****分类统计数据*****");}}??