我如何解决这个问题 Spring Boot 应用程序？

Question

I am developing a spring boot application and facing below
exception tried many way still not able to resolve it help me on this.
Below is the error shown that auto wire with datasource is not instantiating.

> Please find the below structure of my project

                Structure
                Redglass-core       
                    |———> src/main/java
                            ———>com.javalabs.redglass
                                        `   ———>RedglassCoreAPPlication.java

                    |———> src/main/resources
                                ———>application.properties


                    |———> src/test/java
                            ———>com.javalabs.redglass.test
                                        `   ———>RedglassCoreAPPlicationTest.java

                    |————>/src
                            |————>/target
                            |————>pom.xml

Below is the application.properties file

spring.datasource.driver-class-name=com.mysql.jdbc.Driver
spring.datasource.url=jdbc:mysql://localhost:3306/company?useSSL=false&serverTimezone=UTC
spring.datasource.username=root
spring.datasource.password=root

spring.jpa.hibernate.ddl-auto=update

This is my Springboot starter class RedglassCoreAPPlication.java

            package com.javalabs.redglass;

            import org.springframework.boot.SpringApplication;
            import org.springframework.boot.autoconfigure.SpringBootApplication;
            import org.springframework.context.annotation.PropertySource;

            RedglassCoreApplication.java
            @SpringBootApplication
            public class RedglassCoreApplication {
            public static void main(String[] args) {
                SpringApplication.run(RedglassCoreApplication.class, args);
            }
            }

> This is my Springboot Junit test class 

           RedglassCoreApplicationTest.java**


               package com.javalabs.redglass.test;

                import static org.junit.Assert.assertEquals;

                import java.sql.SQLException;
                import javax.sql.DataSource;
                import org.junit.Test;
                import org.junit.runner.RunWith;
                import org.springframework.beans.factory.annotation.Autowired;
                import   
org.springframework.boot.autoconfigure.SpringBootApplication;
                import org.springframework.test.context.ContextConfiguration;
                import
                    org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
                import com.javalabs.redglass.RedglassCoreApplication;
                @RunWith(SpringJUnit4ClassRunner.class)
                @SpringBootApplication(scanBasePackageClasses =        

                 RedglassCoreApplication.class)
                 @ContextConfiguration({"classpath*:/redglass-      
                        core/applicationContext.xml"})
                  public class RedglassCoreApplicationTest {
                  @Autowired
                  DataSource datasource;

                  @Test
                  public void testDummy() throws SQLException
                  {
                  String schema = datasource.getConnection().getCatalog();
                  System.out.println("Schema name  :- "+schema);
                  assertEquals("company", schema);
                  }
                }

This is my maven pom.xml file Pom.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  c.      
              http://maven.apache.org/xsd/maven-4.0.0.xsd">
             <modelVersion>4.0.0</modelVersion>
             <parent>
              <groupId>com.javalabs</groupId>
              <artifactId>redglass</artifactId>
              <version>0.0.1-SNAPSHOT</version>
             </parent>
             <artifactId>redglass-core</artifactId>
             <dependencies>
             <!-- JPA Data (We are going to use Repositories, Entities,   
              Hibernate, etc...) -->
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter-data-jpa</artifactId>
             </dependency>
             <!-- Use MySQL Connector-J -->
             <dependency>
                <groupId>mysql</groupId>
                <artifactId>mysql-connector-java</artifactId>
             </dependency>
             <dependency>
               <groupId>javax.el</groupId>
               <artifactId>javax.el-api</artifactId>
               <version>2.2.4</version>
             </dependency>
             <dependency>
                <groupId>org.hibernate</groupId>
                <artifactId>hibernate-validator</artifactId>
            </dependency>
            <dependency>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-starter-test</artifactId>
                <scope>test</scope>
            </dependency>
            </dependencies>


            </project>

> Seen below is the error which I am not able to fix it :- 

                org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'com.javalabs.redglass.test.RedglassCoreApplicationTest': Injection of autowired dependencies failed; nested exception is org.springframework.beans.factory.BeanCreationException: Could not autowire field: javax.sql.DataSource com.javalabs.redglass.test.RedglassCoreApplicationTest.datasource; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type [javax.sql.DataSource] found for dependency: expected at least 1 bean which qualifies as autowire candidate for this dependency. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true)}
                    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:334) ~[spring-beans-4.2.3.RELEASE.jar:4.2.3.RELEASE]
                    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1214) ~[spring-beans-4.2.3.RELEASE.jar:4.2.3.RELEASE]
                    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.autowireBeanProperties(AbstractAutowireCapableBeanFactory.java:385) ~[spring-beans-4.2.3.RELEASE.jar:4.2.3.RELEASE]
                    at org.springframework.test.context.support.DependencyInjectionTestExecutionListener.injectDependencies(DependencyInjectionTestExecutionListener.java:118) ~[spring-test-4.2.3.RELEASE.jar:4.2.3.RELEASE]
                    at org.springframework.test.context.support.DependencyInjectionTestExecutionListener.prepareTestInstance(DependencyInjectionTestExecutionListener.java:83) ~[spring-test-4.2.3.RELEASE.jar:4.2.3.RELEASE]
                    at org.springframework.test.context.TestContextManager.prepareTestInstance(TestContextManager.java:228) ~[spring-test-4.2.3.RELEASE.jar:4.2.3.RELEASE]
                    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.createTest(SpringJUnit4ClassRunner.java:230) [spring-test-4.2.3.RELEASE.jar:4.2.3.RELEASE]
                    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner$1.runReflectiveCall(SpringJUnit4ClassRunner.java:289) [spring-test-4.2.3.RELEASE.jar:4.2.3.RELEASE]
                    at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12) [junit.jar:4.12]
                    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.methodBlock(SpringJUnit4ClassRunner.java:291) [spring-test-4.2.3.RELEASE.jar:4.2.3.RELEASE]
                    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:249) [spring-test-4.2.3.RELEASE.jar:4.2.3.RELEASE]
                    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:89) [spring-test-4.2.3.RELEASE.jar:4.2.3.RELEASE]
                    at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290) [junit.jar:4.12]
                    at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71) [junit.jar:4.12]
                    at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288) [junit.jar:4.12]
                    at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58) [junit.jar:4.12]
                    at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268) [junit.jar:4.12]
                    at org.springframework.test.context.junit4.statements.RunBeforeTestClassCallbacks.evaluate(RunBeforeTestClassCallbacks.java:61) [spring-test-4.2.3.RELEASE.jar:4.2.3.RELEASE]
                    at org.springframework.test.context.junit4.statements.RunAfterTestClassCallbacks.evaluate(RunAfterTestClassCallbacks.java:70) [spring-test-4.2.3.RELEASE.jar:4.2.3.RELEASE]
                    at org.junit.runners.ParentRunner.run(ParentRunner.java:363) [junit.jar:4.12]
                    at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.run(SpringJUnit4ClassRunner.java:193) [spring-test-4.2.3.RELEASE.jar:4.2.3.RELEASE]
                    at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run(JUnit4TestReference.java:86) [.cp/:na]
                    at org.eclipse.jdt.internal.junit.runner.TestExecution.run(TestExecution.java:38) [.cp/:na]
                    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:538) [.cp/:na]
                    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:760) [.cp/:na]
                    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:460) [.cp/:na]
                    at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:206) [.cp/:na]
                Caused by: org.springframework.beans.factory.BeanCreationException: Could not autowire field: javax.sql.DataSource com.javalabs.redglass.test.RedglassCoreApplicationTest.datasource; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type [javax.sql.DataSource] found for dependency: expected at least 1 bean which qualifies as autowire candidate for this dependency. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true)}
                    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:573) ~[spring-beans-4.2.3.RELEASE.jar:4.2.3.RELEASE]
                    at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:88) ~[spring-beans-4.2.3.RELEASE.jar:4.2.3.RELEASE]
                    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:331) ~[spring-beans-4.2.3.RELEASE.jar:4.2.3.RELEASE]
                    ... 26 common frames omitted
                Caused by: org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type [javax.sql.DataSource] found for dependency: expected at least 1 bean which qualifies as autowire candidate for this dependency. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true)}
                    at org.springframework.beans.factory.support.DefaultListableBeanFactory.raiseNoSuchBeanDefinitionException(DefaultListableBeanFactory.java:1373) ~[spring-beans-4.2.3.RELEASE.jar:4.2.3.RELEASE]
                    at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1119) ~[spring-beans-4.2.3.RELEASE.jar:4.2.3.RELEASE]
                    at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1014) ~[spring-beans-4.2.3.RELEASE.jar:4.2.3.RELEASE]
                    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:545) ~[spring-beans-4.2.3.RELEASE.jar:4.2.3.RELEASE]
                    ... 28 common frames omitted
                11:16:38.402 [main] DEBUG o.s.t.c.s.AbstractDirtiesContextTestExecutionListener - After test class: context [DefaultTestContext@6bedbc4d testClass = RedglassCoreApplicationTest, testInstance = [null], testMethod = [null], testException = [null], mergedContextConfiguration = [MergedContextConfiguration@932bc4a testClass = RedglassCoreApplicationTest, locations = '{classpath*:/redglass-core/applicationContext.xml}', classes = '{}', contextInitializerClasses = '[]', activeProfiles = '{}', propertySourceLocations = '{}', propertySourceProperties = '{}', contextLoader = 'org.springframework.test.context.support.DelegatingSmartContextLoader', parent = [null]]], class annotated with @DirtiesContext [false] with mode [null].
                11:16:38.404 [Thread-0] INFO  o.s.c.s.GenericApplicationContext - Closing org.springframework.context.support.GenericApplicationContext@35aea049: startup date [Fri Jan 11 11:16:38 EST 2019]; root of context hierarchy
                11:16:38.405 [Thread-0] DEBUG o.s.b.f.s.DefaultListableBeanFactory - Returning cached instance of singleton bean 'lifecycleProcessor'
                11:16:38.405 [Thread-0] DEBUG o.s.b.f.s.DefaultListableBeanFactory - Destroying singletons in org.springframework.beans.factory.support.DefaultListableBeanFactory@38145825: defining beans [org.springframework.context.annotation.internalConfigurationAnnotationProcessor,org.springframework.context.annotation.internalAutowiredAnnotationProcessor,org.springframework.context.annotation.internalRequiredAnnotationProcessor,org.springframework.context.annotation.internalPersistenceAnnotationProcessor,org.springframework.context.event.internalEventListenerProcessor,org.springframework.context.event.internalEventListenerFactory,org.springframework.context.annotation.ConfigurationClassPostProcessor.importAwareProcessor,org.springframework.context.annotation.ConfigurationClassPostProcessor.enhancedConfigurationProcessor]; root of factory hierarchy

Answer 1

The DataSource class is not Autowired, its instance can not be controlled by Spring. You probably need to put the @Component annotation above the declaration of the DataSource class or create an @Bean that returns an instance of the class.

But first check the database connection settings present in src / main / resources / application.properties.

 @Component public class DataSource { (...) }

 @SpringBootApplication public class RedglassCoreApplication { public static void main(String[] args) { SpringApplication.run(RedglassCoreApplication.class, args); } @Bean public DataSource dataSource() { return //DataSource Instance } }

If neither option works check your database connection settings present in src / main / resources / application.properties