ssm-购物车实现3-jt-web

package com.jt.web.controller;

import java.util.List;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.RequestMapping;

import com.jt.common.po.Cart;
import com.jt.web.service.CartService;

@Controller
@RequestMapping("/cart")
public class CartController {
    @Autowired
    private CartService cartService;
    //http://www.jt.com/cart/show.html
    //跳转购物车
    @RequestMapping("/show")
    public String show(Model model){
        //根据userId查询购物车信息
        Long userId=7L;
        List cartList=cartService.findCartByUserId(userId);
        //将cartList数据保存到request对象中
        model.addAttribute("cartList", cartList);
        return "cart";
    }
}

package com.jt.web.service;

import java.io.IOException;
import java.util.List;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import com.fasterxml.jackson.databind.ObjectMapper;
import com.jt.common.po.Cart;
import com.jt.common.service.HttpClientService;
import com.jt.common.vo.SysResult;

@Service
public class CartServiceImpl implements CartService {
    @Autowired
    private HttpClientService httpClient;
    private static ObjectMapper objectMapper=new ObjectMapper();

    @SuppressWarnings("unchecked")
    @Override
    public List findCartByUserId(Long userId) {
        String url="http://cart.jt.com/cart/query/"+userId;
        String resultJSON = httpClient.doGet(url);
        List cartList=null;
        try {
            SysResult sysResult = objectMapper.readValue(resultJSON, SysResult.class);
            cartList=(List) sysResult.getData();
            
        } catch (IOException e) {
            e.printStackTrace();
            throw new RuntimeException();
        }
        return cartList;
    }
}

package com.jt.common.vo;

import java.io.Serializable;
import java.util.List;

import com.fasterxml.jackson.annotation.JsonIgnoreProperties;
import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.ObjectMapper;

/**
 * 京淘商城自定义响应结构
 */
@JsonIgnoreProperties(ignoreUnknown=true)
public class SysResult implements Serializable{
    private static final long serialVersionUID = 1L;

    // 定义jackson对象
    private static final ObjectMapper MAPPER = new ObjectMapper();

    // 响应业务状态
    /*
     * 200  成功
     * 201  错误
     * 400  参数错误
     */
    private Integer status;

    // 响应消息
    private String msg;

    // 响应中的数据
    private Object data;

    public static SysResult build(Integer status, String msg, Object data) {
        return new SysResult(status, msg, data);
    }

    public static SysResult oK(Object data) {
        return new SysResult(data);
    }

    public static SysResult oK() {
        return new SysResult(null);
    }

    public SysResult() {

    }

    public static SysResult build(Integer status, String msg) {
        return new SysResult(status, msg, null);
    }

    public SysResult(Integer status, String msg, Object data) {
        this.status = status;
        this.msg = msg;
        this.data = data;
    }

    public SysResult(Object data) {
        this.status = 200;
        this.msg = "OK";
        this.data = data;
    }

    
    public Boolean isOk() {
        return this.status == 200;
    }

    public Integer getStatus() {
        return status;
    }

    public void setStatus(Integer status) {
        this.status = status;
    }

    public String getMsg() {
        return msg;
    }

    public void setMsg(String msg) {
        this.msg = msg;
    }

    public Object getData() {
        return data;
    }

    public void setData(Object data) {
        this.data = data;
    }

    /**
     * 将json结果集转化为SysResult对象
     * 
     * @param jsonData json数据
     * @param clazz SysResult中的object类型
     * @return
     */
    public static SysResult formatToPojo(String jsonData, Class clazz) {
        try {
            if (clazz == null) {
                return MAPPER.readValue(jsonData, SysResult.class);
            }
            JsonNode jsonNode = MAPPER.readTree(jsonData);
            JsonNode data = jsonNode.get("data");
            Object obj = null;
            if (clazz != null) {
                if (data.isObject()) {
                    obj = MAPPER.readValue(data.traverse(), clazz);
                } else if (data.isTextual()) {
                    obj = MAPPER.readValue(data.asText(), clazz);
                }
            }
            return build(jsonNode.get("status").intValue(), jsonNode.get("msg").asText(), obj);
        } catch (Exception e) {
            e.printStackTrace();
            return null;
        }
    }

    /**
     * 没有object对象的转化
     * 
     * @param json
     * @return
     */
    public static SysResult format(String json) {
        try {
            return MAPPER.readValue(json, SysResult.class);
        } catch (Exception e) {
            e.printStackTrace();
        }
        return null;
    }

    /**
     * Object是集合转化
     * 
     * @param jsonData json数据
     * @param clazz 集合中的类型
     * @return
     */
    public static SysResult formatToList(String jsonData, Class clazz) {
        try {
            JsonNode jsonNode = MAPPER.readTree(jsonData);
            JsonNode data = jsonNode.get("data");
            Object obj = null;
            if (data.isArray() && data.size() > 0) {
                obj = MAPPER.readValue(data.traverse(),
                        MAPPER.getTypeFactory().constructCollectionType(List.class, clazz));
            }
            return build(jsonNode.get("status").intValue(), jsonNode.get("msg").asText(), obj);
        } catch (Exception e) {
            e.printStackTrace();
            return null;
        }
    }

}

package com.jt.web.service;

import java.io.IOException;
import java.util.List;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import com.fasterxml.jackson.databind.ObjectMapper;
import com.jt.common.po.Cart;
import com.jt.common.service.HttpClientService;
import com.jt.common.vo.SysResult;

@Service
public class CartServiceImpl implements CartService {
    @Autowired
    private HttpClientService httpClient;
    private static ObjectMapper objectMapper=new ObjectMapper();

    @SuppressWarnings("unchecked")
    @Override
    public List findCartByUserId(Long userId) {
        String url="http://cart.jt.com/cart/query/"+userId;
        String resultJSON = httpClient.doGet(url);
        List cartList=null;
        try {
            SysResult sysResult = objectMapper.readValue(resultJSON, SysResult.class);
            cartList=(List) sysResult.getData();
            
        } catch (IOException e) {
            e.printStackTrace();
            throw new RuntimeException();
        }
        return cartList;
    }
}