在一个列表中存储以下元素：apple,grape,banana,pear 3.1 返回集合中的最大的和最小的元素 3.2 将集合进行排序，并将排序后的结果打印在控制台上 [必做题]

比较类

public class name implements Comparator{

	

	@Override
	public int compare(f o1, f o2) {
		
		return o2.getName().compareTo(o1.getName());
	}

}

映射类

			private String name;

			public String getName() {
				return name;
			}

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

			@Override
			public int hashCode() {
				final int prime = 31;
				int result = 1;
				result = prime * result + ((name == null) ? 0 : name.hashCode());
				return result;
			}

			@Override
			public boolean equals(Object obj) {
				if (this == obj)
					return true;
				if (obj == null)
					return false;
				if (getClass() != obj.getClass())
					return false;
				f other = (f) obj;
				if (name == null) {
					if (other.name != null)
						return false;
				} else if (!name.equals(other.name))
					return false;
				return true;
			}

			@Override
			public String toString() {
				return "f [name=" + name + "]";
			}

			public f(String name) {
				super();
				this.name = name;
			}

			public f() {
				super();
			}
			

测试

package pro1218test;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.Collections;
import java.util.List;




			ArrayList  s=new ArrayList<>();
			f   f1=new f("apple");
			f  f2=new f("grape");
			f  f3=new f("banana");
			f  f4=new f("pear");
			
			s.add(f1);
			s.add(f2);
			s.add(f3);
			s.add(f4);
			System.out.println(s);
			f max=Collections.max(s,new name());
			System.out.println(max);
			f min =Collections.min(s,new name());
			System.out.println(min);
			Collections.sort(s,new name());
			System.out.println(s);
		}