配置Spring Mybatis JUnit测试环境的应用上下文

刘伟

　　Spring-test模块中的应用上下文和web及spring boot的有很大差异。主要试下来差异有：

• 单元测试的app context不支持从外部properties文件注入属性
  
• @Value注解不能解析带通配符的路径字符串
  

　　解决第一个问题可以配置一个PropertyPlaceholderConfigurer的bean。
　　第二个问题的具体实例是：
　　@Value(value = "classpath:mybatis/sqlmap/**/*.xml")
　　private Resource[] mapperLocations;
　　解决此问题的一个变通办法是用PathMatchingResourcePatternResolver的getResources()方法来达到相同功能。
　　以下代码是完整的例子：

package com.abc.app1.dao;
import com.alibaba.druid.filter.Filter;
import com.alibaba.druid.filter.stat.StatFilter;
import com.alibaba.druid.pool.DruidDataSource;
import org.mybatis.spring.SqlSessionFactoryBean;
import org.mybatis.spring.annotation.MapperScan;
import org.springframework.beans.factory.annotation.Autowire;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.beans.factory.config.PropertyPlaceholderConfigurer;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.ComponentScan;
import org.springframework.context.annotation.Configuration;
import org.springframework.core.io.ClassPathResource;
import org.springframework.core.io.Resource;
import org.springframework.core.io.support.PathMatchingResourcePatternResolver;
import org.springframework.jdbc.datasource.DataSourceTransactionManager;
import org.springframework.transaction.PlatformTransactionManager;
import org.springframework.transaction.support.TransactionTemplate;
import java.io.IOException;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;
import java.util.Properties;
@Configuration
@MapperScan(basePackageClasses = MapperMarker.class)
@ComponentScan(basePackageClasses = RepositoryMarker.class)
public class UTDalConfig {
@Bean
public PropertyPlaceholderConfigurer propertyPlaceHolderConfigurer() {
PropertyPlaceholderConfigurer cfg = new PropertyPlaceholderConfigurer();
Resource resource = new ClassPathResource("application.properties");
cfg.setLocations(resource);
return cfg;
}
@Bean(autowire = Autowire.BY_NAME)
public SqlSessionFactoryBean sqlSessionFactory() {
try {
SqlSessionFactoryBean ssfb = new SqlSessionFactoryBean();
PathMatchingResourcePatternResolver resolver = new PathMatchingResourcePatternResolver();
Resource[] mapperLocations = resolver.getResources("classpath:mybatis/sqlmap/**/*.xml");
ssfb.setMapperLocations(mapperLocations);
ssfb.setTypeAliasesPackage("com.pajk.ic.api.model.domain");
return ssfb;
}
catch (IOException e) {
e.printStackTrace();
}
return null;
}
@Bean(initMethod = "init", destroyMethod = "close")
@Autowired
public DruidDataSource dataSource(
@Value("${jdbc.url}") String url,
@Value("${jdbc.username}") String username,
@Value("${jdbc.password}") String password,
@Value("${jdbc.maxActive}") int maxActive,
@Value("${jdbc.maxWait}") int maxWait,
@Value("${jdbc.initialSize}") int initialSize,
@Value("${jdbc.minIdle}") int minIdle,
@Value("${jdbc.slowSqlMillis}") int slowSqlMillis
) throws SQLException {
DruidDataSource druidDataSource = new DruidDataSource();
druidDataSource.setUrl(url);
druidDataSource.setUsername(username);
druidDataSource.setPassword(password);
druidDataSource.setMaxActive(maxActive);
druidDataSource.setInitialSize(initialSize);
druidDataSource.setMaxWait(maxWait);//30s
druidDataSource.setMinIdle(minIdle);
druidDataSource.setTimeBetweenEvictionRunsMillis(3000);
druidDataSource.setMinEvictableIdleTimeMillis(300000);
druidDataSource.setValidationQuery("select 1");
druidDataSource.setTestWhileIdle(true);
druidDataSource.setTestOnBorrow(false);
druidDataSource.setTestOnReturn(false);
druidDataSource.setPoolPreparedStatements(true);
druidDataSource.setMaxPoolPreparedStatementPerConnectionSize(20);
druidDataSource.setFilters("config");
Properties properties = new Properties();
properties.put("config.decrypt", "true");
druidDataSource.setConnectProperties(properties);
StatFilter statFilter = new StatFilter();
statFilter.setSlowSqlMillis(slowSqlMillis);//5s。。慢
statFilter.setMergeSql(true);
List<Filter> filterList = new ArrayList<Filter>();
filterList.add(statFilter);
druidDataSource.setProxyFilters(filterList);
return druidDataSource;
}
@Bean(autowire = Autowire.BY_NAME)
public TransactionTemplate transactionTemplate() {
TransactionTemplate template = new TransactionTemplate();
return template;
}
@Bean(autowire = Autowire.BY_NAME)
public PlatformTransactionManager transactionManager() {
return new DataSourceTransactionManager();
}
}

　　此例的数据源配置使用的阿里巴巴的Druid。你可以换成如DBCP，cp30等实现。不过Druid应该是比较强大和稳定的数据库连接池解决方案。