从 hashmap 中删除所有符合特定条件的对象

Question

情况如下。我有：

public class Management {

    private HashMap<Integer, Book> allBooks = new HashMap<>();

    public void deleteAllBooksFromOwner(Owner owner) {
    }

    public class Owner {
        private String name;
        // getters
    }

    public class Book {
        private Owner owner;
        // getters
    }
}

我想在管理class中写一个删除书籍的方法：

public void deleteAllBooksFromOwner(Owner owner){
}

我不知道如何访问书主，供我比较。吸气剂可用。

Answer 1

您可以使用removeIf

public void deleteAllBooksFromOwner(Owner owner) {
    allBooks.entrySet().removeIf(entry -> entry.getValue().getOwner().equals(owner));
}

从 hashmap 中删除所有符合特定条件的对象

Delete all objects from hashmap that match specific condition

java

getter

object

hashmap