我正在编写一个存储ArrayList Person个Person个对象的程序（输入来自文本文件）。
这是Person类的代码，我将从中创建import java.io.Serializable;
public class Person implements Comparable<Person>, Serializable
{
private String firstName;
private String lastName;
private int age;
public Person(String firstName, String lastName, int age)
{
this.firstName = firstName;
this.lastName = lastName.toUpperCase();
this.age = age;
}
public int getAge()
{
return age;
}
public String getName()
{
return firstName;
}
/**
* @return a String of the details of a person in the format:
* Name: <firstName> <lastName> Age: <age>
*/
public String toString()
{
return
"Name: " + firstName + "" + lastName + "\t\t" + "Age: " + age;
}
/**
* Compare the age of the current instance of Person to another age of the specified Person
* @return negative number this < p
* @return 0 if this == p
* @return positive number if this > p
*/
public int compareTo(Person p) {
return ((Integer)this.getAge()).compareTo(p.getAge());
}
个对象：
Comparable我创建了一个public interface Comparable<T> {
public int compareTo(T o);
}
界面：
Collection以下是名为ArrayList的类的代码，它将创建一个Person来存储import java.io.*;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;
import java.util.StringTokenizer;
import java.util.Iterator;
public class Collection
{
private ArrayList<Person> people;
public Collection()
{
people = new ArrayList<Person>();
}
public void readFromFile(String filename)
{
// code that will get input to assign values to fields to a Person
Person newPerson = new Person(firstNameToken, lastNameToken, ageToken);
}
/**
* Prints the details of each person held in the people ArrayList
*/
public void printDetails()
{
Iterator<Person> it = people.iterator();
while(it.hasNext())
{
Person p = it.next();
System.out.println(p.toString());
}
}
public static void main(String [] args) throws FileNotFoundException
{
Collection c = new Collection();
// check
//for(Person person : c.people)
//{
// System.out.println(person);
//}
Collections.sort(c.people);
}
}
个对象，我省略了部分代码，因为它很长：
{{1}}
但是我收到此错误，排序不起作用：
线程“main”中的异常java.lang.Error：未解决的编译问题：绑定不匹配：类型集合的泛型方法sort（List）不适用于参数（ArrayList）。推断类型Person不是有界参数＆gt;
的有效替代
有谁知道为什么？我正在疯狂地寻找谷歌的解决方案，我看不出我错过了什么。我已经实现了类似的..
答案 0 :(得分：6)
我创建了一个Comparable接口：public interface Comparable {public int compareTo（T o）; }
您不应该创建自己的界面。使用java.lang.Comparable<T>，即Collections.sort()方法希望您的对象实现的方法