@Profile注解用于实现通过修改运行时参数，切换不同的开发环境
@Profile注解可以加在类上，也可以加载注入bean的方法上
下面是为了实现不同环境加载不同的数据库具体的代码
import com.mchange.v2.c3p0.ComboPooledDataSource;
import org.springframework.beans.factory.annotation.Configurable;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.context.EmbeddedValueResolverAware;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Profile;
import org.springframework.context.annotation.PropertySource;
import org.springframework.util.StringValueResolver;import javax.sql.DataSource;
import java.beans.PropertyVetoException;//@Profile("test")
@PropertySource(value = "classpath:/jdbc.properties")
@Configurable
public class MainConfigProfile implements EmbeddedValueResolverAware {private StringValueResolver resolver;@Value("${db.user}")private String user;@Value("${db.driverClass}")private String driverCalss;@Profile("dev")@Bean("dataSourceDev")public DataSource dataSourceDev(@Value("${db.password}") String password) throws PropertyVetoException {ComboPooledDataSource dataSource = new ComboPooledDataSource();dataSource.setUser(user);dataSource.setPassword(password);dataSource.setDriverClass(driverCalss);dataSource.setJdbcUrl("jdbc:mysql://localhost:3306/test");return dataSource;}@Profile("test")@Bean("dataSourceTest")public DataSource dataSourceTest(@Value("${db.password}") String password) throws PropertyVetoException {ComboPooledDataSource dataSource = new ComboPooledDataSource();dataSource.setUser(user);dataSource.setPassword(password);dataSource.setDriverClass(driverCalss);dataSource.setJdbcUrl("jdbc:mysql://localhost:3306/ifp");return dataSource;}@Profile("prod")@Bean("dataSourceProd")public DataSource dataSourceProd(@Value("${db.password}") String password) throws PropertyVetoException {ComboPooledDataSource dataSource = new ComboPooledDataSource();dataSource.setUser(user);dataSource.setPassword(password);dataSource.setDriverClass(driverCalss);dataSource.setJdbcUrl("jdbc:mysql://localhost:3306/mysql");return dataSource;}@Overridepublic void setEmbeddedValueResolver(StringValueResolver resolver) {this.resolver = resolver;}
}测试时可以加虚拟机参数-Dspring.profiles.active=XXX切换不同环境
也可以用代码设置参数，具体代码如下：
applicationContext = new AnnotationConfigApplicationContext();applicationContext.getEnvironment().setActiveProfiles("dev");applicationContext.register(MainConfigProfile.class);applicationContext.refresh();