mysql java spring项目仅在第一次运行时显示错误，再次运行后运行正常。为什么呢？
我正在开发一个使用java+spring和MySql作为DB的web应用程序。 我刚刚完成了编写bean及其属性的工作，在出现了几个错误之后，当我第一次运行它时，应用程序显示了一个错误，但是在清除控制台并再次运行它之后，错误消失了，并且似乎工作正常
这些是豆子：
import java.util.ArrayList;
import java.util.List;
import javax.persistence.Column;
import javax.persistence.ElementCollection;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.Table;
import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;
@Data
@Entity
@Table(name = "ssub_drivers")
@NoArgsConstructor
@AllArgsConstructor
public class SubDriver {
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
@Column(updatable = false)
private int id;
private int driverId;
private int tz;
private String lastName;
private String firstName;
@ElementCollection
private List<String> driverFiles=new ArrayList<>();
}
import java.sql.Date;
import java.util.ArrayList;
import java.util.List;
import javax.persistence.Column;
import javax.persistence.ElementCollection;
import javax.persistence.Entity;
import javax.persistence.EnumType;
import javax.persistence.Enumerated;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.Table;
import com.lukman.vehicle.enums.Level;
import com.lukman.vehicle.enums.Status;
import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;
@Data
@Entity
@Table(name = "ssafety_officers")
@NoArgsConstructor
@AllArgsConstructor
public class SafetyOff {
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
@Column(updatable = false)
private int id;
private int tz;
private String lastName;
private String firstName;
private int dlNumber;
@Enumerated(EnumType.STRING)
@ElementCollection
private List<Level> dlLevel = new ArrayList<>();;
private int credentials;
private Date dateOfBirth;
private String permits;
private String ordinations;
}
import java.sql.Date;
import java.util.ArrayList;
import java.util.List;
import javax.persistence.CascadeType;
import javax.persistence.Column;
import javax.persistence.ElementCollection;
import javax.persistence.Entity;
import javax.persistence.EnumType;
import javax.persistence.Enumerated;
import javax.persistence.FetchType;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.OneToMany;
import javax.persistence.Table;
import org.aspectj.apache.bcel.generic.Type;
import com.lukman.vehicle.enums.Education;
import com.lukman.vehicle.enums.Level;
import com.lukman.vehicle.enums.Status;
import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;
@Data
@Entity
@Table(name = "ddrivers")
@NoArgsConstructor
@AllArgsConstructor
public class Driver {
@Id
@GeneratedValue(strategy = GenerationType.IDENTITY)
@Column(updatable = false)
private int id;
private int tz;
private String lastName;
private String firstName;
private int dlNumber;
@Enumerated(EnumType.STRING)
@ElementCollection
private List<Level> dlLevel = new ArrayList<>();;
private Date drivingSince;
private Date expires;
private Date dateOfBirth;
private String adress;
@Enumerated(EnumType.STRING)
private Status status;
private Education education;
@OneToMany(cascade = { CascadeType.REMOVE, CascadeType.PERSIST }, orphanRemoval = true, fetch = FetchType.EAGER,mappedBy = "driverId")
private List<SubDriver> subDrivers = new ArrayList<>();
private String department;
@ElementCollection
private List<String> driverFiles=new ArrayList<>();
}
错误：
Error executing DDL "alter table driver_dl_level drop foreign key FKrauifkcf0b58iujn4ayrgksjb" via JDBC Statement
控制台：
. ____ _ __ _ _
/\\ / ___'_ __ _ _(_)_ __ __ _ \ \ \ \
( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \
\\/ ___)| |_)| | | | | || (_| | ) ) ) )
' |____| .__|_| |_|_| |_\__, | / / / /
=========|_|==============|___/=/_/_/_/
:: Spring Boot :: (v2.4.3)
2021-02-25 17:45:02.995 INFO 43552 --- [ restartedMain] com.lukman.vehicle.VehicleApplication : Starting VehicleApplication using Java 11.0.10 on DESKTOP-6C4F0HE with PID 43552 (C:\Users\User\Desktop\vehicle\target\classes started by User in C:\Users\User\Desktop\vehicle)
2021-02-25 17:45:02.999 INFO 43552 --- [ restartedMain] com.lukman.vehicle.VehicleApplication : No active profile set, falling back to default profiles: default
2021-02-25 17:45:03.097 INFO 43552 --- [ restartedMain] .e.DevToolsPropertyDefaultsPostProcessor : Devtools property defaults active! Set 'spring.devtools.add-properties' to 'false' to disable
2021-02-25 17:45:03.097 INFO 43552 --- [ restartedMain] .e.DevToolsPropertyDefaultsPostProcessor : For additional web related logging consider setting the 'logging.level.web' property to 'DEBUG'
2021-02-25 17:45:04.074 INFO 43552 --- [ restartedMain] .s.d.r.c.RepositoryConfigurationDelegate : Bootstrapping Spring Data JPA repositories in DEFAULT mode.
2021-02-25 17:45:04.168 INFO 43552 --- [ restartedMain] .s.d.r.c.RepositoryConfigurationDelegate : Finished Spring Data repository scanning in 81 ms. Found 3 JPA repository interfaces.
2021-02-25 17:45:05.577 INFO 43552 --- [ restartedMain] o.s.b.w.embedded.tomcat.TomcatWebServer : Tomcat initialized with port(s): 8080 (http)
2021-02-25 17:45:05.592 INFO 43552 --- [ restartedMain] o.apache.catalina.core.StandardService : Starting service [Tomcat]
2021-02-25 17:45:05.592 INFO 43552 --- [ restartedMain] org.apache.catalina.core.StandardEngine : Starting Servlet engine: [Apache Tomcat/9.0.43]
2021-02-25 17:45:05.738 INFO 43552 --- [ restartedMain] o.a.c.c.C.[Tomcat].[localhost].[/] : Initializing Spring embedded WebApplicationContext
2021-02-25 17:45:05.738 INFO 43552 --- [ restartedMain] w.s.c.ServletWebServerApplicationContext : Root WebApplicationContext: initialization completed in 2640 ms
2021-02-25 17:45:06.034 INFO 43552 --- [ restartedMain] o.hibernate.jpa.internal.util.LogHelper : HHH000204: Processing PersistenceUnitInfo [name: default]
2021-02-25 17:45:06.115 INFO 43552 --- [ restartedMain] org.hibernate.Version : HHH000412: Hibernate ORM core version 5.4.28.Final
2021-02-25 17:45:06.315 INFO 43552 --- [ restartedMain] o.hibernate.annotations.common.Version : HCANN000001: Hibernate Commons Annotations {5.1.2.Final}
2021-02-25 17:45:06.457 INFO 43552 --- [ restartedMain] com.zaxxer.hikari.HikariDataSource : HikariPool-1 - Starting...
2021-02-25 17:45:06.863 INFO 43552 --- [ restartedMain] com.zaxxer.hikari.HikariDataSource : HikariPool-1 - Start completed.
2021-02-25 17:45:06.882 INFO 43552 --- [ restartedMain] org.hibernate.dialect.Dialect : HHH000400: Using dialect: org.hibernate.dialect.MySQL8Dialect
2021-02-25 17:45:07.742 WARN 43552 --- [ restartedMain] o.h.t.s.i.ExceptionHandlerLoggedImpl : org.hibernate.tool.schema.spi.CommandAcceptanceException: Error executing DDL "alter table driver_dl_level drop foreign key FKrauifkcf0b58iujn4ayrgksjb" via JDBC Statement
at org.hibernate.tool.schema.internal.exec.GenerationTargetToDatabase.accept(GenerationTargetToDatabase.java:67) ~[hibernate-core-5.4.28.Final.jar:5.4.28.Final]
at org.hibernate.tool.schema.internal.SchemaDropperImpl.applySqlString(SchemaDropperImpl.java:375) ~[hibernate-core-5.4.28.Final.jar:5.4.28.Final]
at org.hibernate.tool.schema.internal.SchemaDropperImpl.applySqlStrings(SchemaDropperImpl.java:359) ~[hibernate-core-5.4.28.Final.jar:5.4.28.Final]
at org.hibernate.tool.schema.internal.SchemaDropperImpl.applyConstraintDropping(SchemaDropperImpl.java:331) ~[hibernate-core-5.4.28.Final.jar:5.4.28.Final]
at org.hibernate.tool.schema.internal.SchemaDropperImpl.dropFromMetadata(SchemaDropperImpl.java:230) ~[hibernate-core-5.4.28.Final.jar:5.4.28.Final]
at org.hibernate.tool.schema.internal.SchemaDropperImpl.performDrop(SchemaDropperImpl.java:154) ~[hibernate-core-5.4.28.Final.jar:5.4.28.Final]
at org.hibernate.tool.schema.internal.SchemaDropperImpl.doDrop(SchemaDropperImpl.java:126) ~[hibernate-core-5.4.28.Final.jar:5.4.28.Final]
at org.hibernate.tool.schema.internal.SchemaDropperImpl.doDrop(SchemaDropperImpl.java:112) ~[hibernate-core-5.4.28.Final.jar:5.4.28.Final]
at org.hibernate.tool.schema.spi.SchemaManagementToolCoordinator.performDatabaseAction(SchemaManagementToolCoordinator.java:145) ~[hibernate-core-5.4.28.Final.jar:5.4.28.Final]
at org.hibernate.tool.schema.spi.SchemaManagementToolCoordinator.process(SchemaManagementToolCoordinator.java:73) ~[hibernate-core-5.4.28.Final.jar:5.4.28.Final]
at org.hibernate.internal.SessionFactoryImpl.<init>(SessionFactoryImpl.java:318) ~[hibernate-core-5.4.28.Final.jar:5.4.28.Final]
at org.hibernate.boot.internal.SessionFactoryBuilderImpl.build(SessionFactoryBuilderImpl.java:468) ~[hibernate-core-5.4.28.Final.jar:5.4.28.Final]
at org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl.build(EntityManagerFactoryBuilderImpl.java:1259) ~[hibernate-core-5.4.28.Final.jar:5.4.28.Final]
at org.springframework.orm.jpa.vendor.SpringHibernateJpaPersistenceProvider.createContainerEntityManagerFactory(SpringHibernateJpaPersistenceProvider.java:58) ~[spring-orm-5.3.4.jar:5.3.4]
at org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean.createNativeEntityManagerFactory(LocalContainerEntityManagerFactoryBean.java:365) ~[spring-orm-5.3.4.jar:5.3.4]
at org.springframework.orm.jpa.AbstractEntityManagerFactoryBean.buildNativeEntityManagerFactory(AbstractEntityManagerFactoryBean.java:409) ~[spring-orm-5.3.4.jar:5.3.4]
at org.springframework.orm.jpa.AbstractEntityManagerFactoryBean.afterPropertiesSet(AbstractEntityManagerFactoryBean.java:396) ~[spring-orm-5.3.4.jar:5.3.4]
at org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean.afterPropertiesSet(LocalContainerEntityManagerFactoryBean.java:341) ~[spring-orm-5.3.4.jar:5.3.4]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1845) ~[spring-beans-5.3.4.jar:5.3.4]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1782) ~[spring-beans-5.3.4.jar:5.3.4]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:602) ~[spring-beans-5.3.4.jar:5.3.4]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:524) ~[spring-beans-5.3.4.jar:5.3.4]
at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:335) ~[spring-beans-5.3.4.jar:5.3.4]
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:234) ~[spring-beans-5.3.4.jar:5.3.4]
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:333) ~[spring-beans-5.3.4.jar:5.3.4]
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:208) ~[spring-beans-5.3.4.jar:5.3.4]
at org.springframework.context.support.AbstractApplicationContext.getBean(AbstractApplicationContext.java:1153) ~[spring-context-5.3.4.jar:5.3.4]
at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:907) ~[spring-context-5.3.4.jar:5.3.4]
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:582) ~[spring-context-5.3.4.jar:5.3.4]
at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:144) ~[spring-boot-2.4.3.jar:2.4.3]
at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:767) ~[spring-boot-2.4.3.jar:2.4.3]
at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:759) ~[spring-boot-2.4.3.jar:2.4.3]
at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:426) ~[spring-boot-2.4.3.jar:2.4.3]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:326) ~[spring-boot-2.4.3.jar:2.4.3]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1311) ~[spring-boot-2.4.3.jar:2.4.3]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1300) ~[spring-boot-2.4.3.jar:2.4.3]
at com.lukman.vehicle.VehicleApplication.main(VehicleApplication.java:10) ~[classes/:na]
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:na]
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:na]
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:na]
at java.base/java.lang.reflect.Method.invoke(Method.java:566) ~[na:na]
at org.springframework.boot.devtools.restart.RestartLauncher.run(RestartLauncher.java:49) ~[spring-boot-devtools-2.4.3.jar:2.4.3]
Caused by: java.sql.SQLSyntaxErrorException: Table 'vehiclefleet.driver_dl_level' doesn't exist
at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:120) ~[mysql-connector-java-8.0.17.jar:8.0.17]
at com.mysql.cj.jdbc.exceptions.SQLError.createSQLException(SQLError.java:97) ~[mysql-connector-java-8.0.17.jar:8.0.17]
at com.mysql.cj.jdbc.exceptions.SQLExceptionsMapping.translateException(SQLExceptionsMapping.java:122) ~[mysql-connector-java-8.0.17.jar:8.0.17]
at com.mysql.cj.jdbc.StatementImpl.executeInternal(StatementImpl.java:764) ~[mysql-connector-java-8.0.17.jar:8.0.17]
at com.mysql.cj.jdbc.StatementImpl.execute(StatementImpl.java:648) ~[mysql-connector-java-8.0.17.jar:8.0.17]
at com.zaxxer.hikari.pool.ProxyStatement.execute(ProxyStatement.java:95) ~[HikariCP-3.4.5.jar:na]
at com.zaxxer.hikari.pool.HikariProxyStatement.execute(HikariProxyStatement.java) ~[HikariCP-3.4.5.jar:na]
at org.hibernate.tool.schema.internal.exec.GenerationTargetToDatabase.accept(GenerationTargetToDatabase.java:54) ~[hibernate-core-5.4.28.Final.jar:5.4.28.Final]
... 41 common frames omitted
应用程序属性：
spring.datasource.username=root
spring.datasource.password=12345
spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver
spring.jpa.properties.hibernate.dialect = org.hibernate.dialect.MySQL8Dialect
spring.jpa.properties.hibernate.enable_lazy_load_no_trans=true
spring.jackson.serialization.fail_on_empty_beans=false
spring.jpa.hibernate.ddl-auto= create-drop
波姆。xml:
<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>2.4.3</version>
<relativePath /> <!-- lookup parent from repository -->
</parent>
<groupId>com.lukman</groupId>
<artifactId>vehicle</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>vehicle</name>
<description>managing vehicle fleet</description>
<properties>
<java.version>11</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>org.springframework.boot</groupId>
<artifactId>spring-boot-devtools</artifactId>
<scope>runtime</scope>
<optional>true</optional>
</dependency>
<dependency>
<groupId>javax.xml.bind</groupId>
<artifactId>jaxb-api</artifactId>
<version>2.3.0</version>
</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>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
<configuration>
<excludes>
<exclude>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
</exclude>
</excludes>
</configuration>
</plugin>
</plugins>
</build>
</project>
<?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>2.4.3</version>
<relativePath /> <!-- lookup parent from repository -->
</parent>
<groupId>com.lukman</groupId>
<artifactId>vehicle</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>vehicle</name>
<description>managing vehicle fleet</description>
<properties>
<java.version>11</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>org.springframework.boot</groupId>
<artifactId>spring-boot-devtools</artifactId>
<scope>runtime</scope>
<optional>true</optional>
</dependency>
<dependency>
<groupId>javax.xml.bind</groupId>
<artifactId>jaxb-api</artifactId>
<version>2.3.0</version>
</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>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
<configuration>
<excludes>
<exclude>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
</exclude>
</excludes>
</configuration>
</plugin>
</plugins>
</build>
</project>
共 (0) 个答案