Bound Mismatch Error: The Type is not a valid substitute
绑定不匹配错误:类型不是有效的替代
Task: I want to store "Song class object" in ImmutableSet through PlayList class.
任务:我想通过播放列表类在immutable et中存储“Song类对象”。
I have three classes.
我有三个类。
public class ImmutableBinaryTree< T extends Comparable<T>> implements ImmutableSet<T> { }
public class Song { }
public class PlayList<T extends Comparable<T>> {
private Song songs;
ImmutableSet<Song> immutableSet; // Bound Mismatch error occurring here
1 个解决方案
#1
3
If you are adding a Song to ImmutableBinaryTree song must satisfy the bounds of the type parameter on ImmutableBinaryTree, meaning it must implement the Comparable interface since the type parameter specifies the bounds T extends Comparable<T>.
如果要将歌曲添加到ImmutableBinaryTree Song，则必须满足ImmutableBinaryTree上的类型参数的界限，这意味着它必须实现可比接口，因为类型参数指定了边界T扩展可比的
public class Song implements Comparable<Song>{
@Override
public int compareTo(Song arg0) {
//provide implementation here
//See effective java for appropriate implementation conditions
return 0;
}
}
#1
3
If you are adding a Song to ImmutableBinaryTree song must satisfy the bounds of the type parameter on ImmutableBinaryTree, meaning it must implement the Comparable interface since the type parameter specifies the bounds T extends Comparable<T>.
如果要将歌曲添加到ImmutableBinaryTree Song，则必须满足ImmutableBinaryTree上的类型参数的界限，这意味着它必须实现可比接口，因为类型参数指定了边界T扩展可比的
public class Song implements Comparable<Song>{
@Override
public int compareTo(Song arg0) {
//provide implementation here
//See effective java for appropriate implementation conditions
return 0;
}
}