@Entity
@Cacheable
@Cache(usage = CacheConcurrencyStrategy.READ_WRITE, region = "employees")
public class Employee { ... }

@Entity
@Cacheable(true)  // Включено кеширование (по умолчанию true)
public class Product { ... }

spring.jpa.properties.hibernate.cache.use_query_cache=true

spring.jpa.properties.hibernate.cache.use_second_level_cache=true
spring.jpa.properties.hibernate.cache.region.factory_class=org.hibernate.cache.ehcache.EhCacheRegionFactory
(Пример для Ehcache; также поддерживаются Infinispan, Hazelcast, Redis.)

spring.jpa.properties.javax.persistence.sharedCache.mode=ALL
(Варианты: ALL, NONE, ENABLE_SELECTIVE, DISABLE_SELECTIVE.)

<dependency>
    <groupId>org.ehcache</groupId>
    <artifactId>ehcache</artifactId>
</dependency>

И файл ehcache.xml в resources/.

import java.util.function.Function;

public class Task070425 {
    public static void main(String[] args) {
        Function<Integer, Integer> f = x -> x++;
        System.out.println(f.apply(5));
    }
}

@Entity
public class Parent {
    @Id
    private Long id;

    @OneToMany(mappedBy = "parent")
    @Cascade({CascadeType.PERSIST, CascadeType.REMOVE})
    private List<Child> children;
}

@Entity
public class Author {
    @Id
    private Long id;

    @OneToMany(mappedBy = "author")
    @Cascade({CascadeType.MERGE, CascadeType.DELETE_ORPHAN})
    private List<Book> books;
}

@Entity
public class Order {
    @Id
    private Long id;

    @OneToMany(mappedBy = "order")
    @Cascade({CascadeType.LOCK, CascadeType.REPLICATE})
    private List<Item> items;
}

@OneToMany(mappedBy = "parent", cascade = {javax.persistence.CascadeType.PERSIST, javax.persistence.CascadeType.REMOVE})

@OneToMany(mappedBy = "parent")
@Cascade({org.hibernate.annotations.CascadeType.SAVE_UPDATE, org.hibernate.annotations.CascadeType.DELETE_ORPHAN})

@ColumnTransformer(read = "decrypt(credit_card_num, 'my_secret_key')")
private String creditCardNumber;

@ColumnTransformer(write = "encrypt(?, 'my_secret_key')")
private String password;

SELECT decrypt(credit_card_num, 'my_secret_key') FROM users WHERE id = 1;

INSERT INTO users (password) VALUES (encrypt('qwerty', 'my_secret_key'));

@Entity
public class User {
    @Id 
    private Long id;

    @ColumnTransformer(
        read = "pgp_sym_decrypt(credit_card_num, 'secret_key')",
        write = "pgp_sym_encrypt(?, 'secret_key')"
    )
    @Column(name = "credit_card_num")
    private String creditCardNumber;
}

@ColumnTransformer(
    read = "CAST(price AS decimal(10,2))",
    write = "CAST(? AS varchar)"
)
private BigDecimal price;

@ColumnTransformer(
    read = "COALESCE(status, 'DEFAULT')"
)
private String status;

import java.util.function.Supplier;

public class Task080425 {
    public static void main(String[] args) {
        int x = 5;
        Supplier<Integer> lambda = () -> x + 1;
        x = 10;
        System.out.println(lambda.get());
    }
}

@Entity
@DynamicInsert
public class User { ... }

User user = new User();
user.setId(1L);
user.setName("Alice"); // age = null

INSERT INTO user (id, name, age) VALUES (1, 'Alice', NULL);

@DynamicInsert
@Entity
public class User { ... }

INSERT INTO user (id, name) VALUES (1, 'Alice');  -- поле age пропущено!

hibernate.dynamic_insert=true  # Применяется ко всем сущностям!

@DynamicInsert
@Entity
public class Product {
    @Id 
    private Long id;
    private String name;
    private Integer stock;  // Часто null для новых товаров
}

INSERT INTO product (id, name) VALUES (1, 'Laptop');

@DynamicInsert
@Entity
public class Account {
    @Id 
    private Long id;

    @ColumnDefault("0")
    private BigDecimal balance;  // Если null, БД подставит 0
}