Android 客户端通过内置API（HttpClient) 访问 服务器(用Spring MVC 架构) 返回的json数据全过程

************************************************************服务器端代码**************************************************************************

Spring Web MVC(Servlet) 具体细节就不说了，比较不一样的地方，下面会注明！

1. web.xml 的内容如下:

<?xml version="1.0" encoding="UTF-8"?> <web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" id="WebApp_ID" version="2.5"> <display-name>FCAS</display-name> <servlet> <servlet-name>foodcenter</servlet-name> <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class> <load-on-startup>1</load-on-startup> </servlet> <servlet-mapping> <servlet-name>foodcenter</servlet-name> <url-pattern>*.json</url-pattern> </servlet-mapping> </web-app>
2. foodcenter-servlet.xml 的内容如下：

<?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:p="http://www.springframework.org/schema/p" xmlns:context="http://www.springframework.org/schema/context" xsi:schemaLocation=" http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.0.xsd"> <context:annotation-config/> <!-- Controller 类的注解标识--> <context:component-scan base-package="com.liuxi.foodcenter.controller"/> <!--这个ViewResolver 的具体原来没细究，不过CV战士们 中的一员，这样用是没问题的(参考官文) --> <bean class="org.springframework.web.servlet.view.ContentNegotiatingViewResolver"> <property name="mediaTypes"> <map> <entry key="json" value="application/json"/> <!-- 告诉视图解析器 返回的类型为json 格式 --> </map> </property> <property name="defaultViews"> <list> <!-- 这个 View 比较重要,ModelAndView 里的数据变成JSON --> <bean class="org.springframework.web.servlet.view.json.MappingJacksonJsonView"> </bean> </list> </property> </bean> <!--真正的项目，业务Bean 有专门对应的配置文件，这里为了简单起见，就写在这里了 --> <bean id="foodService" class="com.liuxi.food.service.FoodServiceImpl"/> </beans>
3. 子控制器FindFoodListController.java

package com.liuxi.foodcenter.controller; import java.util.HashMap; import java.util.List; import java.util.Map; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.beans.factory.annotation.Qualifier; import org.springframework.stereotype.Controller; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RequestParam; import org.springframework.web.servlet.ModelAndView; import com.liuxi.bean.Food; import com.liuxi.food.service.IFoodService; @Controller public class FindFoodListController { @Autowired @Qualifier("foodService") private IFoodService foodService; /** 根据餐菜的类别返回 该类别下的所有菜*/ @RequestMapping("/findFoodList") public ModelAndView queryFoodList(@RequestParam("typeId") int typeId){ List<Food> list=foodService.getFoodListByType(typeId); ModelAndView modelView=new ModelAndView(); Map<String,Object> modelMap=new HashMap<String,Object>(); modelMap.put("FOOD_LIST", list); modelMap.put("TYPE_ID", typeId); modelView.addAllObjects(modelMap); return modelView; } }
4. FoodServiceImpl.java

package com.liuxi.food.service; import java.util.ArrayList; import java.util.List; import com.liuxi.bean.Food; public class FoodServiceImpl implements IFoodService{ @Override public List<Food> getFoodListByType(int typeId) { //这里本来要调DAO层接口的，这边暂时写死 Food food1=new Food(1,1,"鱼香肉丝", 12.00,"好吃的不得了-鱼香肉丝",4.5,5.0); Food food2=new Food(2,1,"农家小炒肉", 15.00,"好吃的不得了-农家小炒肉",3.7,4.3); Food food3=new Food(3,1,"韭菜炒蛋", 10.00,"好吃的不得了-韭菜炒蛋",2.6,3.0); Food food4=new Food(4,1,"回锅肉", 13.00,"好吃的不得了-回锅肉",3.1,3.8); Food food5=new Food(5,1,"宫保鸡丁", 14.00,"好吃的不得了-宫保鸡丁",3.7,5.0); Food food6=new Food(6,1,"苦瓜炒蛋", 9.00,"好吃的不得了-宫保鸡丁",4.9,4.7); Food food7=new Food(7,1,"莴笋肉片", 10.00,"好吃的不得了-莴笋肉片",2.6,3.9); List<Food> list=new ArrayList<Food>(); list.add(food1); list.add(food2); list.add(food3); list.add(food4); list.add(food5); list.add(food6); list.add(food7); return list; } }
5.IFoodService.java

package com.liuxi.food.service; import java.util.List; import com.liuxi.bean.Food; public interface IFoodService { List<Food> getFoodListByType(int typeId); }

6.Food.java

package com.liuxi.bean; public class Food { private int id; // ID private String name; // 菜名 private double price; // 价格 private String notes; // 菜的简要介绍 private int foodTypeId; // 菜所属的类别 private double kouWeiScore; // 口味的分值 private double hotLevel; // 星级别 public Food(int id, int foodTypeId, String name, double price, String notes, double kouWeiScore, double hotLevel) { this.id = id; this.name = name; this.price = price; this.notes = notes; this.foodTypeId = foodTypeId; this.kouWeiScore = kouWeiScore; this.hotLevel = hotLevel; } public Food() { } public int getId() { return id; } public void setId(int id) { this.id = id; } public String getName() { return name; } public void setName(String name) { this.name = name; } public double getPrice() { return price; } public void setPrice(double price) { this.price = price; } public String getNotes() { return notes; } public void setNotes(String notes) { this.notes = notes; } public int getFoodTypeId() { return foodTypeId; } public void setFoodTypeId(int foodTypeId) { this.foodTypeId = foodTypeId; } public double getKouWeiScore() { return kouWeiScore; } public void setKouWeiScore(double kouWeiScore) { this.kouWeiScore = kouWeiScore; } public double getHotLevel() { return hotLevel; } public void setHotLevel(double hotLevel) { this.hotLevel = hotLevel; } public String toString() { return id + "--" + name + "--" + price + "--" + notes + "--" + foodTypeId + "--" + kouWeiScore + "--" + hotLevel; } }
7.Spring Web MVC 中 将ModelAndView 中的数据自动转换成json ，靠的是jackjson 中 连个jar 包 (这个下载大本营里有下,花了我2积分哦)

jackson-core-asl-1.4.2.jar

jackson-mapper-asl-1.4.2.jar

*************************************以上是服务器端代码，已全部贴完!**********************************************

访问链接是: http://192.168.1.104:8088/FCAS/findFoodList.json?typeId=1

***************************************************************************Android 客户端 访问部分************************************************************

下面进入 Android 客户端访问部分(这里暂不贴 界面，用android 的单元测试 来 测试 服务器返回的json 数据是什么样的

8. GetFoodListTest.java

package com.liuxi.takeorder.test; import java.io.BufferedReader; import java.io.InputStreamReader; import java.util.ArrayList; import org.apache.http.HttpResponse; import org.apache.http.HttpStatus; import org.apache.http.NameValuePair; import org.apache.http.client.HttpClient; import org.apache.http.client.entity.UrlEncodedFormEntity; import org.apache.http.client.methods.HttpPost; import org.apache.http.impl.client.DefaultHttpClient; import org.apache.http.message.BasicNameValuePair; import android.test.AndroidTestCase; import android.util.Log; public class GetFoodListTest extends AndroidTestCase { private static final String TAG="GetFoodListTest"; public void testFindFoodList() { String uri="http://192.168.1.104:8088/FCAS/findFoodList.json?typeId=1"; try{ HttpClient httpClient=new DefaultHttpClient(); //HttpPost 实现 HttpUriRequest 接口,HttpUriRequest接口 继承 HttpRequest HttpPost httpPostReq=new HttpPost(uri); ArrayList<NameValuePair> paramList=new ArrayList<NameValuePair>(); NameValuePair param1=new BasicNameValuePair("typeId",String.valueOf(1)); paramList.add(param1); httpPostReq.setEntity(new UrlEncodedFormEntity(paramList)); HttpResponse resp=httpClient.execute(httpPostReq); if(resp.getStatusLine().getStatusCode()==HttpStatus.SC_OK){ BufferedReader reader=new BufferedReader( new InputStreamReader(resp.getEntity().getContent()) ); StringBuffer result=new StringBuffer(); String inputLine=null; while((inputLine=reader.readLine())!=null){ result.append(inputLine); } Log.i(TAG, result.toString()); } }catch(Exception e){ Log.i(TAG,e.getMessage()); } } }

9. 激动人心的时刻-----> 结果是啥？

日志记录为:

07-19 16:12:53.282: INFO/GetFoodListTest(1287): {"TYPE_ID":1,"FOOD_LIST":[{"name":"鱼香肉丝","id":1,"price":12.0,"notes":"好吃的不得了-鱼香肉丝","foodTypeId":1,"kouWeiScore":4.5,"hotLevel":5.0},{"name":"农家小炒肉","id":2,"price":15.0,"notes":"好吃的不得了-农家小炒肉","foodTypeId":1,"kouWeiScore":3.7,"hotLevel":4.3},{"name":"韭菜炒蛋","id":3,"price":10.0,"notes":"好吃的不得了-韭菜炒蛋","foodTypeId":1,"kouWeiScore":2.6,"hotLevel":3.0},{"name":"回锅肉","id":4,"price":13.0,"notes":"好吃的不得了-回锅肉","foodTypeId":1,"kouWeiScore":3.1,"hotLevel":3.8},{"name":"宫保鸡丁","id":5,"price":14.0,"notes":"好吃的不得了-宫保鸡丁","foodTypeId":1,"kouWeiScore":3.7,"hotLevel":5.0},{"name":"苦瓜炒蛋","id":6,"price":9.0,"notes":"好吃的不得了-宫保鸡丁","foodTypeId":1,"kouWeiScore":4.9,"hotLevel":4.7},{"name":"莴笋肉片","id":7,"price":10.0,"notes":"好吃的不得了-莴笋肉片","foodTypeId":1,"kouWeiScore":2.6,"hotLevel":3.9}]}

我把上面{} 里的东西 放到一个foodlist.json 文件中，格式化后的内容如下：

{ "TYPE_ID" : 1, "FOOD_LIST" : [{ "name" : "鱼香肉丝", "id" : 1, "price" : 12.0, "notes" : "好吃的不得了-鱼香肉丝", "foodTypeId" : 1, "kouWeiScore" : 4.5, "hotLevel" : 5.0 }, { "name" : "农家小炒肉", "id" : 2, "price" : 15.0, "notes" : "好吃的不得了-农家小炒肉", "foodTypeId" : 1, "kouWeiScore" : 3.7, "hotLevel" : 4.3 }, { "name" : "韭菜炒蛋", "id" : 3, "price" : 10.0, "notes" : "好吃的不得了-韭菜炒蛋", "foodTypeId" : 1, "kouWeiScore" : 2.6, "hotLevel" : 3.0 }, { "name" : "回锅肉", "id" : 4, "price" : 13.0, "notes" : "好吃的不得了-回锅肉", "foodTypeId" : 1, "kouWeiScore" : 3.1, "hotLevel" : 3.8 }, { "name" : "宫保鸡丁", "id" : 5, "price" : 14.0, "notes" : "好吃的不得了-宫保鸡丁", "foodTypeId" : 1, "kouWeiScore" : 3.7, "hotLevel" : 5.0 }, { "name" : "苦瓜炒蛋", "id" : 6, "price" : 9.0, "notes" : "好吃的不得了-宫保鸡丁", "foodTypeId" : 1, "kouWeiScore" : 4.9, "hotLevel" : 4.7 }, { "name" : "莴笋肉片", "id" : 7, "price" : 10.0, "notes" : "好吃的不得了-莴笋肉片", "foodTypeId" : 1, "kouWeiScore" : 2.6, "hotLevel" : 3.9 }] }
10. OK! 返回数据正确。

************************************************Spring 是用ObjectMapper 将 数据转换成json 数据的*****************************

下面自己写了个转换的例子:

ObjectMapperTest.java

package com.bean.test; import java.util.ArrayList; import java.util.HashMap; import java.util.List; import java.util.Map; import org.codehaus.jackson.map.ObjectMapper; public class ObjectMapperTest { /** * @param args */ public static void main(String[] args) throws Exception { ObjectMapper mapper=new ObjectMapper(); Map<String,Object> foodListData=new HashMap<String,Object>(); List list=new ArrayList(); Map<String,Object> foodData=new HashMap<String,Object>(); foodData.put("id", 1); foodData.put("name", "鱼香肉丝"); foodData.put("price", 12.00); foodData.put("notes", "好吃啊，真的!"); foodData.put("kouWeiScore", 4.5); foodData.put("hotLevel", 5.0); list.add(foodData); foodListData.put("foodlist", list); String str=mapper.writeValueAsString(foodListData); System.out.println(str); } }
上述程序输出的是:

{"foodlist":[{"id":1,"kouWeiScore":4.5,"price":12.0,"hotLevel":5.0,"name":"鱼香肉丝","notes":"好吃啊，真的!"}]}

format 下：

{
"foodlist" : [{
"id" : 1,
"kouWeiScore" : 4.5,
"price" : 12.0,
"hotLevel" : 5.0,
"name" : "鱼香肉丝",
"notes" : "好吃啊，真的!"
}]
}

好吧，就到这里了。基本架子搭好，接着，就用这个架子来 实现 Android 客户端+Spring MVC 去做后面的项目。继续挖矿。。。。