包含bean 'xxx '的循环引用-考虑将工厂方法声明为静态以独立于其包含实例

Question

我正在使用spring创建两个项目globalDB和GlobalWeb。我想在GlobalWeb中创建多个数据库连接，Jdbc属性是在GlobalWeb启动时从GlobalDB项目dao层获取的。当我运行全球网络时，我遇到了以下异常。

org.springframework.beans.factory.BeanCreation异常：创建名为"globalWebConfig"的bean时出错：自动构建依赖项的注入失败；嵌套异常org.springframework.beans.factory.BeanCreation异常：无法自动构建字段：com.kla.it.dao.com.kla.it.global.conf.GlobalWebConfig.dao；嵌套异常org.springframework.beans.factory.创建名为daoImpl的bean时出错：自动加载依赖项的注入失败；嵌套异常org.springframework.beans.factory.BeanCreation异常：无法自动绑定字段：org.springframework.jdbc.core.JdbcTemboardcom.kla.it.dao.impl.DaoImpl.template；嵌套异常是org.springframework.beans.factory.不满足依赖异常：错误创建bean与名称'模板'定义在类路径资源[com/kla/it/数据库/数据库onfig.class]：不满足依赖表示通过构造函数参数与索引0的类型[javax.sql.数据源]:: 创建名为'partsDs'的bean时出错com.kla.it.global.conf.GlobalWebConfig：通过工厂方法的Bean实例化失败；嵌套异常org.springframework.beans.BeanInstantiation异常：无法实例化[org.springframework.jdbc.datasource.DriverManagerDataSource]：涉及包含bean'globalWebConfig的循环引用-考虑将工厂方法声明为静态，以便独立于其包含的实例。工厂方法getPartsDataSource抛出异常；嵌套异常java.lang.NullPointerExctive；嵌套异常org.springframework.beans.factory.BeanCreation异常：创建名为partsDs的bean时出错com.kla.it.global.conf.GlobalWebConfig中定义：通过工厂方法进行Bean实例化失败；嵌套异常是org. springframework. bean。BeanInstantiation异常：实例化[org. springframework. jdbc. datasource失败。DriverManagerDataSource]：涉及包含bean的循环引用“globalWebConfig”——考虑将工厂方法声明为静态，以便独立于其包含的实例。工厂方法“getPartsDataSource”抛出异常；嵌套异常是java. lang。nullPointerExctive位于org. springframework. bean. factory. anNotation。AutowiredAnNotationBeanPostProcessor. postProcess财产价值（AutowiredAnNotationBeanPostProcessor. java： 334）位于org. springframework. bean. Factory. support。AbstractAutowireCapableBeanFactory. java： 1214）位于org. springframework. bean. Factory。AbstractAutowireCapableBeanFactory. doCreateBean（AbstractAutowireCapableBeanFactory. java： 5AbstractBeanFactory1美元. getObject（AbstractBeanFactory. java： 305）在org. springframework. bean. factory. support。DefaultSingletonBean注册. getSingleton（DefaultSingletonBean注册. java： 230）在org. springframework. bean. factory. support。AbstractBeanFactory. doGetBean（AbstractBeanFactory. java： 301）在org. springframework. bean. factory. support。AbstractBeanFactory. getBean（AbstractBeanFactory. java： 196）在org. springframework. bean. support。DefaultListableBeanFactory. preInstantiateSingletons（DefaultListableBeanFactory. java： 772）在org. springframework. content. support。摘要在org. apache. catalina. core的标准内容。开始内部（标准内容。java： 5143）。生命之源。启动（生命之源：183）在org. apache. catalina. core。容器基地。addChild内部（容器基地。java： 717）在org. apache. catalina. core。容器基地。addchild（容器基地。java： 690）在org. apache. catalina. core。标准主机。addchild（标准主机。java： 705）

GlobalDB配置类

@Configuration
@ComponentScan(basePackages = "com.kla.it")
@PropertySource(value = {"classpath:database.properties"})
public class DatabaseConfig {

    @Autowired
    private Environment env;

//    @Bean(name="ds")
    public DataSource getDataSource(){
        System.out.println("++++++++++++++++DATABASE++++++++++++++START++++++++++++");
        System.out.println("Method to crate data source");
        DriverManagerDataSource ds = new DriverManagerDataSource();
        ds.setDriverClassName("net.snowflake.client.jdbc.SnowflakeDriver");
        ds.setUrl(env.getRequiredProperty("db.url"));
        ds.setUsername(env.getRequiredProperty( "db.username"));
        ds.setPassword(env.getRequiredProperty( "db.password"));
        return ds;
    }

    @Bean(name="template")
    public JdbcTemplate jdbcTemplate(DataSource ds) {
        System.out.println("Jdbc template method called.");
        JdbcTemplate template = new JdbcTemplate(ds);
        template.setResultsMapCaseInsensitive(true);
        System.out.println("++++++++++++++++DATABASE++++++++++++++END+++++++++++");
        return template;
    }
}

GlobalDB Dao层类

@Repository
@Qualifier("dao")
public class DaoImpl implements Dao{

    @Autowired
    JdbcTemplate template;
  @Override
    public Map<String, String> getConnectionsData(String appName, String env) {

        List<Map<String, Object>> reportsList = new ArrayList<>();
        Map<String, String> dataSourceMap = new HashMap<>();
        String qry = "SELECT * FROM DB_CONFIG WHERE name = '"+appName+"' AND ev = '"+env+"'";
         reportsList = template.queryForList(qry);
            int count = 1;
            for (Map<String, Object> map : reportsList) {
                dataSourceMap.put(String.valueOf(map.get("prop")), String.valueOf(map.get("val")));
            }
        return dataSourceMap;

    }
}

GlobalWeb配置类

@Configuration
@EnableWebMvc
@ComponentScan(basePackages = "com.kla.it")
@PropertySource(value = {"classpath:global.properties"})
public class GlobalWebConfig extends WebMvcConfigurerAdapter {

    @Autowired(required=true)
    Dao dao;

     @Bean(name = "partsDs")
     public DriverManagerDataSource getPartsDataSource(){
        Map<String, String> dsMap = dao.getConnectionsData("parts", "dev");
        DriverManagerDataSource partsDs= new DriverManagerDataSource();
        partsDs.setDriverClassName(dsMap.get("driver"));
        partsDs.setUrl(dsMap.get("url"));
        partsDs.setUsername(dsMap.get("user"));
        partsDs.setPassword(dsMap.get("password"));   
        return partsDs;
    }

     @Bean(name = "cosmosDs")
      public DriverManagerDataSource getCosmosDataSource(){
        Map<String, String> dsMap = dao.getConnectionsData("cosmos", "dev");
        DriverManagerDataSource cosmosDs = new DriverManagerDataSource();
        cosmosDs.setDriverClassName(dsMap.get("driver"));
        cosmosDs.setUrl(dsMap.get("url"));
        cosmosDs.setUsername(dsMap.get("user"));
        cosmosDs.setPassword(dsMap.get("password"));   
        return cosmosDs;
    }

      @Bean(name = "itsDs")
       public DataSource getITSDataSource(){
        Map<String, String> dsMap = dao.getConnectionsData("ITSecurity", "dev");
        DriverManagerDataSource itsDs= new DriverManagerDataSource();
        itsDs.setDriverClassName(dsMap.get("driver"));
        itsDs.setUrl(dsMap.get("url"));
        itsDs.setUsername(dsMap.get("user"));
        itsDs.setPassword(dsMap.get("password"));   
        return itsDs;
    }

    @Bean(name = "sfPartsDB")
    public JdbcTemplate snowFlakeParts() {
        System.out.println("Jdbc template method called.");
        DataSource cosmosDs = getPartsDataSource();
        JdbcTemplate sfPartsDB = new JdbcTemplate(cosmosDs);
        sfPartsDB.setResultsMapCaseInsensitive(true);
        return sfPartsDB;
    }

    @Bean(name = "sfCosmosDB")
    public JdbcTemplate snowFlakeCosmos() {
        System.out.println("Jdbc template method called.");
        DataSource cosmosDs = getCosmosDataSource();
        JdbcTemplate sfCosmosDB = new JdbcTemplate(cosmosDs);
        sfCosmosDB.setResultsMapCaseInsensitive(true);
        return sfCosmosDB;
    }
//    
    @Bean(name = "oracleDB")
    public JdbcTemplate oracleTemplate() {
        DataSource itsDs = getITSDataSource();
        JdbcTemplate oracleDB = new JdbcTemplate(itsDs);
        oracleDB.setResultsMapCaseInsensitive(true);
        return oracleDB;
    }
}

Answer 1

请尝试以下代码。真管用
1@特定数据源引用的限定符（按名称）
2@导入聚合所有配置类

    @Configuration
    @ComponentScan(basePackages = "com.kla.it")
    @PropertySource(value = {"classpath:database.properties"})
    public class DatabaseConfig {

        @Autowired
        private Environment env;

        @Bean(name="ds")
        public DataSource getDataSource(){
            System.out.println("++++++++++++++++DATABASE++++++++++++++START++++++++++++");
            System.out.println("Method to crate data source");
            DriverManagerDataSource ds = new DriverManagerDataSource();
            ds.setDriverClassName("net.snowflake.client.jdbc.SnowflakeDriver");
            ds.setUrl(env.getRequiredProperty("db.url"));
            ds.setUsername(env.getRequiredProperty( "db.username"));
            ds.setPassword(env.getRequiredProperty( "db.password"));
            return ds;
        }

        @Bean(name="template")
        public JdbcTemplate jdbcTemplate(@Qualifier("ds")DataSource ds) {
            System.out.println("Jdbc template method called.");
            JdbcTemplate template = new JdbcTemplate(ds);
            template.setResultsMapCaseInsensitive(true);
            System.out.println("++++++++++++++++DATABASE++++++++++++++END+++++++++++");
            return template;
        }
    }   


@Import(DatabaseConfig.class) /* add this line to aggrgate java configuration classes*/
@Configuration
@EnableWebMvc
@ComponentScanenter code here(basePackages = "com.kla.it")
@PropertySource(value = {"classpath:global.properties"})
public class GlobalWebConfig extends WebMvcConfigurerAdapter {
}