springboot多数据源配置

由于我们系统旧环境没有用springboot自带的多数据源功能，使用了自己配置的多数据源。

添加自定义数据源注解

@Target({ElementType.TYPE, ElementType.METHOD})
@Retention(RetentionPolicy.RUNTIME)
public @interface DynDatasource {
    Module value() default Module.DEF;
}

注解扫描

    public CheckoutDatasourceAspect() {
    }

    @Around("@within(com.midea.cloud.dynamicds.aop.anno.DynDatasource)")
    public Object checkoutDatasource(ProceedingJoinPoint joinPoint) throws Throwable {
        Object var5;
        try {
            MethodSignature methodSignature = (MethodSignature)joinPoint.getSignature();
            DynDatasource dynDatasource = (DynDatasource)methodSignature.getMethod().getDeclaredAnnotation(DynDatasource.class);
            if (dynDatasource == null) {
                dynDatasource = (DynDatasource)methodSignature.getDeclaringType().getDeclaredAnnotation(DynDatasource.class);
            }

            CheckModuleHolder.checkout(dynDatasource.value());
            Object object = joinPoint.proceed();
            var5 = object;
        } catch (Throwable var9) {
            throw var9;
        } finally {
            CheckModuleHolder.release();
        }

        return var5;
    }
}

扫描配置包下的内容，自动加载

@Configuration
@EnableConfigurationProperties({DynamicDatasourceConfigProperties.class})
@ComponentScan({"com.midea.cloud.dynamicds"})
public class DynamicDatasourceAutoConfiguration {
    @Autowired
    private DynamicDatasourceConfigProperties dynamicDatasourceConfigProperties;

    public DynamicDatasourceAutoConfiguration() {
    }

    @Bean
    @ConditionalOnMissingBean
    @ConditionalOnClass({DynamicDatasource.class})
    public DataSource dataSource() {
        DynamicDatasource dynamicDatasource = new DynamicDatasource();
        dynamicDatasource.setDynamicDatasourceConfigProperties(this.dynamicDatasourceConfigProperties);
        return dynamicDatasource;
    }
}

根据启动注解扫描加载对应的配置信息

获取yml文件中指定的配置信息

@ConfigurationProperties(
    prefix = "cloud.scc.dynamic"
)
public class DynamicDatasourceConfigProperties {
    private Module defaultModule;
    private Map<Module, Map<String, Object>> datasouces;

    public DynamicDatasourceConfigProperties() {
    }

    public Module getDefaultModule() {
        return this.defaultModule;
    }

    public void setDefaultModule(Module defaultModule) {
        this.defaultModule = defaultModule;
    }

    public Map<Module, Map<String, Object>> getDatasouces() {
        return this.datasouces;
    }

    public void setDatasouces(Map<Module, Map<String, Object>> datasouces) {
        this.datasouces = datasouces;
    }
}

这里读取配置新的详情，重写springframework中的AbstractDataSource类，读取数据库详细配置信息

public abstract class AbstractDataSource implements DataSource {
    protected final Log logger = LogFactory.getLog(this.getClass());

    public AbstractDataSource() {
    }

    public int getLoginTimeout() throws SQLException {
        return 0;
    }

    public void setLoginTimeout(int timeout) throws SQLException {
        throw new UnsupportedOperationException("setLoginTimeout");
    }

    public PrintWriter getLogWriter() {
        throw new UnsupportedOperationException("getLogWriter");
    }

    public void setLogWriter(PrintWriter pw) throws SQLException {
        throw new UnsupportedOperationException("setLogWriter");
    }

    public <T> T unwrap(Class<T> iface) throws SQLException {
        if (iface.isInstance(this)) {
            return this;
        } else {
            throw new SQLException("DataSource of type [" + this.getClass().getName() + "] cannot be unwrapped as [" + iface.getName() + "]");
        }
    }

    public boolean isWrapperFor(Class<?> iface) throws SQLException {
        return iface.isInstance(this);
    }

    public Logger getParentLogger() {
        return Logger.getLogger("global");
    }
}

配置启动类扫描注解

@Target({ElementType.TYPE})
@Retention(RetentionPolicy.RUNTIME)
@Import({DynamicDatasourceAutoConfiguration.class})
public @interface EnableDynamicDatasource {
}

根据注解自动加载对应的数据库。

public class CheckModuleHolder {
    public static ThreadLocal<Module> moduleThreadLocal = new ThreadLocal();

    public CheckModuleHolder() {
    }

    public static void checkout(Module module) {
        moduleThreadLocal.set(module);
    }

    public static void release() {
        moduleThreadLocal.remove();
    }

    public static Module get() {
        return (Module)moduleThreadLocal.get();
    }
}