Java 对媒体(接口)的ArrayList进行排序
我试图按照媒体的标题对媒体的arraylist(一个实现到电影类和唱片集类中的接口)进行排序 下面是Album类的一些代码,与movie类几乎相同Java 对媒体(接口)的ArrayList进行排序,java,Java,我试图按照媒体的标题对媒体的arraylist(一个实现到电影类和唱片集类中的接口)进行排序 下面是Album类的一些代码,与movie类几乎相同 public class Album implements Media, Comparable<Media> { public Album(String title, int copies, String artist, String songs) { this.title = title; this.c
public class Album implements Media, Comparable<Media> {
public Album(String title, int copies, String artist, String songs) {
this.title = title;
this.copies = copies;
this.artist = artist;
this.songs = songs;
}
public String getTitle() {
return this.title;
}
public int getCopies() {
return this.copies;
}
public String getArtist() {
return this.artist;
}
public String getSongs() {
return this.songs;
}
public String getRating() {
return null;
}
public int compareTo(Media media) {
int answer = 0;
if (this.title.compareTo(media.getTitle()) > 0) {
answer = 1;
} else if (this.title.compareTo(media.getTitle()) < 0) {
answer = -1;
} else if (this.title.compareTo(media.getTitle()) == 0) {
answer = 0;
}
return answer;
}
}
它给出了一个错误“类型集合中的方法排序(List有人知道如何删除错误吗?更新可比较的声明,以使用扩展
媒体的任何子类
public class Album implements Media, Comparable<? extends Media>
public类相册实现媒体,可比
public class Album implements Media, Comparable<? extends Media>