Spring，AWS，访问远程DB：java.lang.AbstractMethodError：null org.springframework.core.OrderComparator.findOrder（OrderComparator.java:142）

Question

Spring boot: I'm trying to access MySQL database on AWS

It works fine with local DB and I can connect to MySQL DB on AWS through MySQL Workbench. Now I'm trying to start my local app to connect remote DB on AWS, and get the following errors:

java.lang.AbstractMethodError: null
at org.springframework.core.OrderComparator.findOrder(OrderComparator.java:142) ~[spring-core-5.0.9.RELEASE.jar:5.0.9.RELEASE]
at org.springframework.core.annotation.AnnotationAwareOrderComparator.findOrder(AnnotationAwareOrderComparator.java:65) ~[spring-core-5.0.9.RELEASE.jar:5.0.9.RELEASE]
at org.springframework.core.OrderComparator.getOrder(OrderComparator.java:125) ~[spring-core-5.0.9.RELEASE.jar:5.0.9.RELEASE]
at org.springframework.core.OrderComparator.getOrder(OrderComparator.java:113) ~[spring-core-5.0.9.RELEASE.jar:5.0.9.RELEASE]
at org.springframework.core.OrderComparator.doCompare(OrderComparator.java:82) ~[spring-core-5.0.9.RELEASE.jar:5.0.9.RELEASE]
at org.springframework.core.OrderComparator.compare(OrderComparator.java:68) ~[spring-core-5.0.9.RELEASE.jar:5.0.9.RELEASE]
at java.base/java.util.TimSort.countRunAndMakeAscending(TimSort.java:360) ~[na:na]
at java.base/java.util.TimSort.sort(TimSort.java:220) ~[na:na]
at java.base/java.util.Arrays.sort(Arrays.java:1514) ~[na:na]
at java.base/java.util.ArrayList.sort(ArrayList.java:1585) ~[na:na]
at org.springframework.boot.SpringApplication.asUnmodifiableOrderedSet(SpringApplication.java:1344) [spring-boot-2.0.5.RELEASE.jar:2.0.5.RELEASE]
at org.springframework.boot.SpringApplication.getListeners(SpringApplication.java:1253) [spring-boot-2.0.5.RELEASE.jar:2.0.5.RELEASE]
at org.springframework.boot.context.event.EventPublishingRunListener.contextLoaded(EventPublishingRunListener.java:85) ~[spring-boot-2.0.5.RELEASE.jar:2.0.5.RELEASE]
at org.springframework.boot.SpringApplicationRunListeners.contextLoaded(SpringApplicationRunListeners.java:66) ~[spring-boot-2.0.5.RELEASE.jar:2.0.5.RELEASE]
at org.springframework.boot.SpringApplication.prepareContext(SpringApplication.java:408) [spring-boot-2.0.5.RELEASE.jar:2.0.5.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:331) [spring-boot-2.0.5.RELEASE.jar:2.0.5.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1277) [spring-boot-2.0.5.RELEASE.jar:2.0.5.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1265) [spring-boot-2.0.5.RELEASE.jar:2.0.5.RELEASE]
at com.xxsc.myapp.MyAppApplication.main(MyAppApplication.java:23) [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:564) ~[na:na]
at org.springframework.boot.devtools.restart.RestartLauncher.run(RestartLauncher.java:49) [spring-boot-devtools-2.0.5.RELEASE.jar:2.0.5.RELEASE]

My pom.xml:

    <dependency>
        <groupId>org.springframework.cloud</groupId>
        <artifactId>spring-cloud-context</artifactId>
        <version>2.1.1.RELEASE</version>
    </dependency>       
    <dependency>
        <groupId>org.springframework.cloud</groupId>
        <artifactId>spring-cloud-starter-aws-jdbc</artifactId>
    </dependency>

My application.properties:

spring.jpa.database-platform=org.hibernate.dialect.MySQLDialect
spring.jpa.show-sql=true
spring.jpa.hibernate.ddl-auto=update
spring.thymeleaf.cache = false

My MyApplication.java

@SpringBootApplication
@EnableRdsInstance(databaseName="xxx", dbInstanceIdentifier="xxx", username="xxx", password="xxx")
@EnableContextRegion(region="xxx")
@EnableContextCredentials(accessKey="xxx", secretKey="xxx")
public class MyAppApplication {
public static void main(String[] args) {
    SpringApplication.run(MyAppApplication.class, args);
}
@Bean
public RdsInstanceConfigurer instanceConfigurer() {
    return new RdsInstanceConfigurer() {

        @Override
        public DataSourceFactory getDataSourceFactory() {
            TomcatJdbcDataSourceFactory dataSourceFactory = new TomcatJdbcDataSourceFactory();

            dataSourceFactory.setInitialSize(2);
            dataSourceFactory.setMaxActive(15);
            dataSourceFactory.setValidationQuery("SELECT 1");
            dataSourceFactory.setTestOnBorrow(true);

            return dataSourceFactory;
        }
    };
}

}

Answer 1

I was using the wrong dependency, it should be:

<dependency>
        <groupId>org.springframework.cloud</groupId>
        <artifactId>spring-cloud-aws-context</artifactId>
</dependency>
<dependency>
        <groupId>org.springframework.cloud</groupId>
        <artifactId>spring-cloud-aws-jdbc</artifactId>
</dependency>       

in the application.properties I need to use

spring.jpa.database-platform=org.hibernate.dialect.MySQL5Dialect. 

(the default version of MySql on Amazon for t2.micro is l5.6)

It works for me.

BTW, I need to create an account under My Security Credentials attached from a group with AmazonRDSFullAccess permissions of course.