将@OneToMany 用于使用 Spring Boot 和 MySQL 的 Web 应用程序会导致创建 bean 出错

Question

我正在尝试将多个 CreditCards 连接到同一个用户，但是在编译程序时出现创建 bean 错误。

用户Class

package com.bookstore.BookStoreDemo.model;

import javax.persistence.*;
import java.util.ArrayList;
import java.util.List;

@Entity
@Table(name = "Users")
public class User {

@Id
@Column(name = "username", updatable = false, nullable = false)
private String username;
@Column(name = "password")
private String password;
@Column(name = "name")
private String name;
@Column(name = "address")
private String address;
@Column(name = "email")
private String email;

@OneToMany(cascade = CascadeType.ALL)
@JoinColumn(name = "user", referencedColumnName = "username")
List<CreditCard> creditCard = new ArrayList<>();

//For Deserialization
public User() {
}

public User(String username) {
    this.username = username;
}

public String getUsername() {
    return username;
}

public void setUsername(String username) {
    this.username = username;
}

public String getPassword() {
    return password;
}

public void setPassword(String password) {
    this.password = password;
}

public String getName() {
    return name;
}

public void setName(String name) {
    this.name = name;
}

public String getAddress() {
    return address;
}

public void setAddress(String address) {
    this.address = address;
}

public String getEmail() {
    return email;
}

public void setEmail(String email) {
    this.email = email;
}

}

信用卡Class

import javax.persistence.*;
import java.math.BigInteger;

@Entity
@Table(name = "CreditCards")
public class CreditCard {

    @Id
    @Column(name = "username")
    private String username;
    @Column(name = "cardNumber")
    private BigInteger cardNumber;
    @Column(name = "expirationDate")
    private Integer expirationDate;
    @Column(name = "securityCode")
    private Integer securityCode;

    //For Deserialization
    public CreditCard() {}

    public CreditCard(String username) {
        this.username = username;
    }

    public BigInteger getCardNumber() {
        return cardNumber;
    }

    public void setCardNumber(BigInteger cardNumber) {
        this.cardNumber = cardNumber;
    }

    public Integer getExpirationDate() {
        return expirationDate;
    }

    public void setExpirationDate(Integer expirationDate) {
        this.expirationDate = expirationDate;
    }

    public Integer getSecurityCode() {
        return securityCode;
    }

    public void setSecurityCode(Integer securityCode) {
        this.securityCode = securityCode;
    }

    public String getUsername() {
        return username;
    }

    public void setUsername(String username) {
        this.username = username;
    }

}

用户资源Class

    package com.bookstore.BookStoreDemo.resource;

import com.bookstore.BookStoreDemo.model.User;
import com.bookstore.BookStoreDemo.repository.UserRepository;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.*;

import java.util.List;
import java.util.Optional;

@RestController
@RequestMapping(value = "/geektext")
public class UserResource {

    @Autowired
    private UserRepository userRepository;

    //Displays User By Username Search
    @GetMapping("/users/{username}")
    public Optional<User> getUserByUsername(@PathVariable String username) {
        Optional<User> users = userRepository.findByUsername(username);
        if (users.isPresent()) {
            return userRepository.findByUsername(username);
        } else{
                throw new RuntimeException("User '" + username + "' not found");
            }
        }

    //Displays User By Name Search
    @GetMapping("/users/{name}")
    public Optional<User> getUserByName(@PathVariable String name) {
        Optional<User> users = userRepository.findByName(name);
        if (users.isPresent()) {
            return userRepository.findByName(name);
        } else{
            throw new RuntimeException("User '" + name + "' not found");
        }
    }

    //Displays List of All Users
    @GetMapping("/users")
    public List<User> getAllUsers() {
        return userRepository.findAll();
    }

    //Creates a New User
    @PostMapping("/users")
    public User loadUser(@RequestBody final User user) {
        user.setEmail(user.getUsername());
        return userRepository.save(user);
    }

    //Creates a List of New Users
    @PostMapping("/users/all")
    public List <User> loadAllUsers(@RequestBody final List <User> users) {
        return userRepository.saveAll(users);
    }

    //Updates an Existing User
    @PutMapping("/users")
    public User updateUser(@RequestBody User user) {
        return userRepository.save(user);
    }

    //Deletes an Existing User
    @DeleteMapping("/users/{username}")
    public String deleteUser(@PathVariable String username) {
        Optional<User> users = userRepository.findById(username);
        if (users.isPresent()) {
            userRepository.delete(users.get());
            return "User '" + username + "' has been deleted";
        } else {
            throw new RuntimeException("User '" + username + "' not found");
        }
    }

}

信用卡资源Class

package com.bookstore.BookStoreDemo.resource;

import com.bookstore.BookStoreDemo.model.CreditCard;
import com.bookstore.BookStoreDemo.model.User;
import com.bookstore.BookStoreDemo.repository.CreditCardRepository;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.*;

import java.util.List;
import java.util.Optional;

@RestController
@RequestMapping(value = "/geektext/users")
class CreditCardResource {

    @Autowired
    CreditCardRepository cardsRepository;

    User user = new User();

    //Displays CreditCard By Username Search
    @GetMapping("/{username}/cards")
    public Optional<CreditCard> getCardsByUsername(@PathVariable String username) {
        Optional<CreditCard> cards = cardsRepository.findByUsername(username);
        if (user.getUsername().matches(username)) {
            return cardsRepository.findByUsername(username);
        } else{
            throw new RuntimeException("User '" + username + "' not found");
        }
    }

    //Displays CreditCard By Name Search
    @GetMapping("/{name}/cards")
    public Optional<CreditCard> getCardsByName(@PathVariable String name) {
        Optional<CreditCard> cards = cardsRepository.findByName(name);
        if (user.getName().matches(name)) {
            return cardsRepository.findByName(name);
        } else{
            throw new RuntimeException("User '" + name + "' not found");
        }
    }

    //Creates New Card for User
    @PostMapping("/{username}/cards")
    public CreditCard loadCard(@RequestBody CreditCard cards, @PathVariable("name") final String username) {
        if (username.equals(user.getUsername())) {
            return cardsRepository.save(cards);
        } else{
            throw new RuntimeException("User '" + username + "' not found");
        }
    }
}

用户存储库接口

package com.bookstore.BookStoreDemo.repository;

import com.bookstore.BookStoreDemo.model.User;
import org.springframework.data.jpa.repository.JpaRepository;
import org.springframework.stereotype.Repository;

import java.util.Optional;

@Repository
public interface UserRepository extends JpaRepository<User, String> {
    Optional<User> findByName(String name);
    Optional<User> findByUsername(String username);

}

CreditCardRepository 接口

package com.bookstore.BookStoreDemo.repository;

import com.bookstore.BookStoreDemo.model.CreditCard;
import org.springframework.data.jpa.repository.JpaRepository;
import org.springframework.stereotype.Repository;

import java.util.Optional;

@Repository
public interface CreditCardRepository extends JpaRepository<CreditCard, String> {
    Optional<CreditCard> findByName(String name);
    Optional<CreditCard> findByUsername(String username);
}

主要

package com.bookstore.BookStoreDemo;

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication
public class BookStoreDemoApplication {

    public static void main(String[] args) {
        SpringApplication.run(BookStoreDemoApplication.class, args);
    }

}

pom.xlm 文件

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.3.2.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>GeekText</groupId>
    <artifactId>Bookstore</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>Bookstore</name>
    <description>Project for a Bookstore using Spring Boot</description>

    <properties>
        <java.version>14</java.version>
    </properties>

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-jpa</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <scope>runtime</scope>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
            <exclusions>
                <exclusion>
                    <groupId>org.junit.vintage</groupId>
                    <artifactId>junit-vintage-engine</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

</project>

代码编译时出现如下错误：

 org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'creditCardRepository': FactoryBean threw exception on object creation; nested exception is java.lang.IllegalArgumentException: Failed to create query for method public abstract java.util.Optional com.bookstore.BookStoreDemo.repository.CreditCardRepository.findByName(java.lang.String)! No property name found for type CreditCard!
    at org.springframework.beans.factory.support.FactoryBeanRegistrySupport.doGetObjectFromFactoryBean(FactoryBeanRegistrySupport.java:176) ~[spring-beans-5.2.8.RELEASE.jar:5.2.8.RELEASE]
    at org.springframework.beans.factory.support.FactoryBeanRegistrySupport.getObjectFromFactoryBean(FactoryBeanRegistrySupport.java:101) ~[spring-beans-5.2.8.RELEASE.jar:5.2.8.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.getObjectForBeanInstance(AbstractBeanFactory.java:1827) ~[spring-beans-5.2.8.RELEASE.jar:5.2.8.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.getObjectForBeanInstance(AbstractAutowireCapableBeanFactory.java:1265) ~[spring-beans-5.2.8.RELEASE.jar:5.2.8.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:334) ~[spring-beans-5.2.8.RELEASE.jar:5.2.8.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:202) ~[spring-beans-5.2.8.RELEASE.jar:5.2.8.RELEASE]
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.getBeansOfType(DefaultListableBeanFactory.java:624) ~[spring-beans-5.2.8.RELEASE.jar:5.2.8.RELEASE]
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.getBeansOfType(DefaultListableBeanFactory.java:612) ~[spring-beans-5.2.8.RELEASE.jar:5.2.8.RELEASE]
    at org.springframework.data.repository.config.DeferredRepositoryInitializationListener.onApplicationEvent(DeferredRepositoryInitializationListener.java:51) ~[spring-data-commons-2.3.2.RELEASE.jar:2.3.2.RELEASE]
    at org.springframework.data.repository.config.DeferredRepositoryInitializationListener.onApplicationEvent(DeferredRepositoryInitializationListener.java:36) ~[spring-data-commons-2.3.2.RELEASE.jar:2.3.2.RELEASE]
    at org.springframework.context.event.SimpleApplicationEventMulticaster.doInvokeListener(SimpleApplicationEventMulticaster.java:172) ~[spring-context-5.2.8.RELEASE.jar:5.2.8.RELEASE]
    at org.springframework.context.event.SimpleApplicationEventMulticaster.invokeListener(SimpleApplicationEventMulticaster.java:165) ~[spring-context-5.2.8.RELEASE.jar:5.2.8.RELEASE]
    at org.springframework.context.event.SimpleApplicationEventMulticaster.multicastEvent(SimpleApplicationEventMulticaster.java:139) ~[spring-context-5.2.8.RELEASE.jar:5.2.8.RELEASE]
    at org.springframework.context.support.AbstractApplicationContext.publishEvent(AbstractApplicationContext.java:404) ~[spring-context-5.2.8.RELEASE.jar:5.2.8.RELEASE]
    at org.springframework.context.support.AbstractApplicationContext.publishEvent(AbstractApplicationContext.java:361) ~[spring-context-5.2.8.RELEASE.jar:5.2.8.RELEASE]
    at org.springframework.context.support.AbstractApplicationContext.finishRefresh(AbstractApplicationContext.java:898) ~[spring-context-5.2.8.RELEASE.jar:5.2.8.RELEASE]
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:554) ~[spring-context-5.2.8.RELEASE.jar:5.2.8.RELEASE]
    at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:143) ~[spring-boot-2.3.2.RELEASE.jar:2.3.2.RELEASE]
    at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:758) ~[spring-boot-2.3.2.RELEASE.jar:2.3.2.RELEASE]
    at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:750) ~[spring-boot-2.3.2.RELEASE.jar:2.3.2.RELEASE]
    at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:397) ~[spring-boot-2.3.2.RELEASE.jar:2.3.2.RELEASE]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:315) ~[spring-boot-2.3.2.RELEASE.jar:2.3.2.RELEASE]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:1237) ~[spring-boot-2.3.2.RELEASE.jar:2.3.2.RELEASE]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:1226) ~[spring-boot-2.3.2.RELEASE.jar:2.3.2.RELEASE]
    at com.bookstore.BookStoreDemo.BookStoreDemoApplication.main(BookStoreDemoApplication.java:10) ~[classes/:na]
Caused by: java.lang.IllegalArgumentException: Failed to create query for method public abstract java.util.Optional com.bookstore.BookStoreDemo.repository.CreditCardRepository.findByName(java.lang.String)! No property name found for type CreditCard!
    at org.springframework.data.jpa.repository.query.PartTreeJpaQuery.<init>(PartTreeJpaQuery.java:96) ~[spring-data-jpa-2.3.2.RELEASE.jar:2.3.2.RELEASE]
    at org.springframework.data.jpa.repository.query.JpaQueryLookupStrategy$CreateQueryLookupStrategy.resolveQuery(JpaQueryLookupStrategy.java:107) ~[spring-data-jpa-2.3.2.RELEASE.jar:2.3.2.RELEASE]
    at org.springframework.data.jpa.repository.query.JpaQueryLookupStrategy$CreateIfNotFoundQueryLookupStrategy.resolveQuery(JpaQueryLookupStrategy.java:218) ~[spring-data-jpa-2.3.2.RELEASE.jar:2.3.2.RELEASE]
    at org.springframework.data.jpa.repository.query.JpaQueryLookupStrategy$AbstractQueryLookupStrategy.resolveQuery(JpaQueryLookupStrategy.java:81) ~[spring-data-jpa-2.3.2.RELEASE.jar:2.3.2.RELEASE]
    at org.springframework.data.repository.core.support.QueryExecutorMethodInterceptor.lookupQuery(QueryExecutorMethodInterceptor.java:99) ~[spring-data-commons-2.3.2.RELEASE.jar:2.3.2.RELEASE]
    at org.springframework.data.repository.core.support.QueryExecutorMethodInterceptor.lambda$mapMethodsToQuery(QueryExecutorMethodInterceptor.java:92) ~[spring-data-commons-2.3.2.RELEASE.jar:2.3.2.RELEASE]
    at java.base/java.util.stream.ReferencePipeline.accept(ReferencePipeline.java:195) ~[na:na]
    at java.base/java.util.Iterator.forEachRemaining(Iterator.java:133) ~[na:na]
    at java.base/java.util.Collections$UnmodifiableCollection.forEachRemaining(Collections.java:1056) ~[na:na]
    at java.base/java.util.Spliterators$IteratorSpliterator.forEachRemaining(Spliterators.java:1801) ~[na:na]
    at java.base/java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:484) ~[na:na]
    at java.base/java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:474) ~[na:na]
    at java.base/java.util.stream.ReduceOps$ReduceOp.evaluateSequential(ReduceOps.java:913) ~[na:na]
    at java.base/java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234) ~[na:na]
    at java.base/java.util.stream.ReferencePipeline.collect(ReferencePipeline.java:578) ~[na:na]
    at org.springframework.data.repository.core.support.QueryExecutorMethodInterceptor.mapMethodsToQuery(QueryExecutorMethodInterceptor.java:94) ~[spring-data-commons-2.3.2.RELEASE.jar:2.3.2.RELEASE]
    at org.springframework.data.repository.core.support.QueryExecutorMethodInterceptor.lambda$new[=20=](QueryExecutorMethodInterceptor.java:84) ~[spring-data-commons-2.3.2.RELEASE.jar:2.3.2.RELEASE]
    at java.base/java.util.Optional.map(Optional.java:258) ~[na:na]
    at org.springframework.data.repository.core.support.QueryExecutorMethodInterceptor.<init>(QueryExecutorMethodInterceptor.java:84) ~[spring-data-commons-2.3.2.RELEASE.jar:2.3.2.RELEASE]
    at org.springframework.data.repository.core.support.RepositoryFactorySupport.getRepository(RepositoryFactorySupport.java:331) ~[spring-data-commons-2.3.2.RELEASE.jar:2.3.2.RELEASE]
    at org.springframework.data.repository.core.support.RepositoryFactoryBeanSupport.lambda$afterPropertiesSet(RepositoryFactoryBeanSupport.java:297) ~[spring-data-commons-2.3.2.RELEASE.jar:2.3.2.RELEASE]
    at org.springframework.data.util.Lazy.getNullable(Lazy.java:212) ~[spring-data-commons-2.3.2.RELEASE.jar:2.3.2.RELEASE]
    at org.springframework.data.util.Lazy.get(Lazy.java:94) ~[spring-data-commons-2.3.2.RELEASE.jar:2.3.2.RELEASE]
    at org.springframework.data.repository.core.support.RepositoryFactoryBeanSupport.getObject(RepositoryFactoryBeanSupport.java:244) ~[spring-data-commons-2.3.2.RELEASE.jar:2.3.2.RELEASE]
    at org.springframework.data.repository.core.support.RepositoryFactoryBeanSupport.getObject(RepositoryFactoryBeanSupport.java:57) ~[spring-data-commons-2.3.2.RELEASE.jar:2.3.2.RELEASE]
    at org.springframework.beans.factory.support.FactoryBeanRegistrySupport.doGetObjectFromFactoryBean(FactoryBeanRegistrySupport.java:169) ~[spring-beans-5.2.8.RELEASE.jar:5.2.8.RELEASE]
    ... 24 common frames omitted
Caused by: org.springframework.data.mapping.PropertyReferenceException: No property name found for type CreditCard!
    at org.springframework.data.mapping.PropertyPath.<init>(PropertyPath.java:94) ~[spring-data-commons-2.3.2.RELEASE.jar:2.3.2.RELEASE]
    at org.springframework.data.mapping.PropertyPath.create(PropertyPath.java:382) ~[spring-data-commons-2.3.2.RELEASE.jar:2.3.2.RELEASE]
    at org.springframework.data.mapping.PropertyPath.create(PropertyPath.java:358) ~[spring-data-commons-2.3.2.RELEASE.jar:2.3.2.RELEASE]
    at org.springframework.data.mapping.PropertyPath.lambda$from[=20=](PropertyPath.java:311) ~[spring-data-commons-2.3.2.RELEASE.jar:2.3.2.RELEASE]
    at java.base/java.util.concurrent.ConcurrentMap.computeIfAbsent(ConcurrentMap.java:330) ~[na:na]
    at org.springframework.data.mapping.PropertyPath.from(PropertyPath.java:293) ~[spring-data-commons-2.3.2.RELEASE.jar:2.3.2.RELEASE]
    at org.springframework.data.mapping.PropertyPath.from(PropertyPath.java:276) ~[spring-data-commons-2.3.2.RELEASE.jar:2.3.2.RELEASE]
    at org.springframework.data.repository.query.parser.Part.<init>(Part.java:82) ~[spring-data-commons-2.3.2.RELEASE.jar:2.3.2.RELEASE]
    at org.springframework.data.repository.query.parser.PartTree$OrPart.lambda$new[=20=](PartTree.java:251) ~[spring-data-commons-2.3.2.RELEASE.jar:2.3.2.RELEASE]
    at java.base/java.util.stream.ReferencePipeline.accept(ReferencePipeline.java:195) ~[na:na]
    at java.base/java.util.stream.ReferencePipeline.accept(ReferencePipeline.java:177) ~[na:na]
    at java.base/java.util.Spliterators$ArraySpliterator.forEachRemaining(Spliterators.java:948) ~[na:na]
    at java.base/java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:484) ~[na:na]
    at java.base/java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:474) ~[na:na]
    at java.base/java.util.stream.ReduceOps$ReduceOp.evaluateSequential(ReduceOps.java:913) ~[na:na]
    at java.base/java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234) ~[na:na]
    at java.base/java.util.stream.ReferencePipeline.collect(ReferencePipeline.java:578) ~[na:na]
    at org.springframework.data.repository.query.parser.PartTree$OrPart.<init>(PartTree.java:252) ~[spring-data-commons-2.3.2.RELEASE.jar:2.3.2.RELEASE]
    at org.springframework.data.repository.query.parser.PartTree$Predicate.lambda$new[=20=](PartTree.java:381) ~[spring-data-commons-2.3.2.RELEASE.jar:2.3.2.RELEASE]
    at java.base/java.util.stream.ReferencePipeline.accept(ReferencePipeline.java:195) ~[na:na]
    at java.base/java.util.stream.ReferencePipeline.accept(ReferencePipeline.java:177) ~[na:na]
    at java.base/java.util.Spliterators$ArraySpliterator.forEachRemaining(Spliterators.java:948) ~[na:na]
    at java.base/java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:484) ~[na:na]
    at java.base/java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:474) ~[na:na]
    at java.base/java.util.stream.ReduceOps$ReduceOp.evaluateSequential(ReduceOps.java:913) ~[na:na]
    at java.base/java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234) ~[na:na]
    at java.base/java.util.stream.ReferencePipeline.collect(ReferencePipeline.java:578) ~[na:na]
    at org.springframework.data.repository.query.parser.PartTree$Predicate.<init>(PartTree.java:382) ~[spring-data-commons-2.3.2.RELEASE.jar:2.3.2.RELEASE]
    at org.springframework.data.repository.query.parser.PartTree.<init>(PartTree.java:97) ~[spring-data-commons-2.3.2.RELEASE.jar:2.3.2.RELEASE]
    at org.springframework.data.jpa.repository.query.PartTreeJpaQuery.<init>(PartTreeJpaQuery.java:89) ~[spring-data-jpa-2.3.2.RELEASE.jar:2.3.2.RELEASE]
    ... 49 common frames omitted

Answer 1

从 CreditCard 中删除以下代码

//Optional<User> findByName(String name);

修改 CreditCardResource


//Displays CreditCard By Name Search
    @GetMapping("/{name}/cards")
    public Optional<CreditCard> getCardsByName(@PathVariable String name) {
        Optional<CreditCard> cards = cardsRepository.findByUsername(name);
        if (user.getName().matches(name)) {
            return cardsRepository.findByUsername(name);
        } else {
            throw new RuntimeException("User '" + name + "' not found");
        }
    }

将@OneToMany 用于使用 Spring Boot 和 MySQL 的 Web 应用程序会导致创建 bean 出错

Using @OneToMany for a Web Application Using Spring Boot and MySQL is giving error creating bean

spring-boot

mapping

one-to-many

spring-framework-beans

beancreationexception