Mongodb总结4-Spring环境使用Mongodb

前几次的例子，要么是Shell，要么是普通Java应用程序的例子。
实际情况，是要在Spring的项目里用，因此需要做一些改造。

1.配置文件
C:\hanhai\config\mongodb.properties
mongodb.host=172.17.100.150
mongodb.port=27017
mongodb.db=zrb

2.配置文件对应的实体类

 public class MongodbConfig {
	private String host;
	private String port;
	private String db;
}

3.Spring扫描配置文件

<context:property-placeholder
		location="file:${zhaorongbao.config_path}/config/mongodb.properties"
		ignore-unresolvable="true" />

4.属性到实体类

<bean id="mongodbConfig" class="com.hanhai.zrb.api.mongodb.MongodbConfig">
    <property name="host" value="${mongodb.host}"></property>
    <property name="port" value="${mongodb.port}"></property>
    <property name="db" value="${mongodb.db}"></property>
</bean>

5.Spring工具类，获得容器中的对象
需要扫描这个类SpringContextUtil
<context:component-scan base-package="com.hanhai.zrb.api.mongodb" />
SpringContextUtil在com.hanhai.zrb.api.mongodb这个包中。

@Component
public class SpringContextUtil implements ApplicationContextAware{

	private static ApplicationContext ctx;
	@Override
	public void setApplicationContext(ApplicationContext applicationContext)
			throws BeansException {
		this.ctx = applicationContext;
	}

	public static ApplicationContext getCtx(){
		return ctx;
	}

	public static Object getBean(String name) throws BeansException {
        return ctx.getBean(name);
	} 

}

6.SpringMVC中使用。
@

Controller
@RequestMapping("mongodb")
public class MongodbTestController extends BaseController {

	@RequestMapping("test")
	public void test(HttpServletResponse response) throws IOException {
		DB db = MongoUtil.db();

		ProjectDetail projectDetail = buildProjectDetail();
		DBCollection projectDetailCollection = db
				.getCollection("projectDetail");
	}

7.MongoUtil工具类。

import java.net.UnknownHostException;

import org.apache.log4j.Logger;

import com.mongodb.DB;
import com.mongodb.Mongo;

public class MongoUtil {
	public static final int DEFAULT_PORT = 27017;
	public static final String DEFAULT_HOST = "172.17.100.150";

	public static Logger log = Logger.getLogger(MongoUtil.class);

	private static Mongo instance;

	//@Resource(name="mongodbConfig")
	//private static MongodbConfig mongodbConfig;
	//没有直接注入
	private static MongodbConfig config = null;

	public static Mongo mongo() {
		//使用工具方法获得容器中的对象
		Object object=SpringContextUtil.getBean("mongodbConfig");

		if(object instanceof MongodbConfig){
			config = (MongodbConfig)object;
		}else{
			log.error("Mongodb config error~");
		}
		try {
			if (instance == null) {
				instance = new Mongo(config.getHost(), Integer.parseInt(config.getPort()));
			}
		} catch (UnknownHostException e) {
			e.printStackTrace();
		}
		return instance;
	}

	public static DB db(){
		Mongo mongo = MongoUtil.mongo();
		DB db = mongo.getDB(config.getDb());
		if(db == null){
			throw new RuntimeException("Mongo db is null");
		}
		return db;
	}

	public static void close() {
		if (instance != null) {
			instance.close();
		}
	}
}