归类统计数据

/**
 * 创建一个测试类
 * 
 * @class Info
 * @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 3:40:05 PM
 */
public class Student {
	private int age;
	private String name;
	private String sex;

	public int getAge() {
		return age;
	}

	public void setAge(int age) {
		this.age = age;
	}

	public String getName() {
		return name;
	}

	public void setName(String name) {
		this.name = name;
	}

	public String getSex() {
		return sex;
	}

	public void setSex(String sex) {
		this.sex = sex;
	}

	public Student(int age, String name, String sex) {
		super();
		this.age = age;
		this.name = name;
		this.sex = sex;
	}
}

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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*****");
	}
}

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