java.util.LinkedHashMap cannot be cast to

上图就是我用restful接口收到的 对象。转为list报错。

那么我是怎么解决的呢。

步骤3步：

1.我先用ResponseEntity ec = restTemplate.getForEntity("http://hello/returnlog", String.class);  得到json

2.我用jackson mapper, 把json转为对象数组。

com.fasterxml.jackson.databind.ObjectMapper mapper = new ObjectMapper();

MetricLog[] mlog = mapper.readValue(ec.getBody(), MetricLog[].class);

3. 对象数组转list集合

java.util.List mlogList = java.util.Arrays.asList(mlog);

代码解释如下：

下面是javabean

public class MetricLog  implements Serializable  {
	   public String MW_Name;
	   public String MW_Host;
	   public Long LId;
	   public java.util.Date Log_Time;
	   public java.lang.String Req_QueryId;
	   public java.lang.String UserId;
	   public java.lang.String Web_ModuleId;
	   public java.lang.String Web_Module_Name;
	   public java.lang.String Log_Level;
	   public java.lang.String Log_Line;
	   public java.lang.String Log_Text;
	   public java.lang.String Log_Error;
	   public java.lang.String Log_Stack;
	   
	   public MetricLog() {
		   this.MW_Host = MetricConstants.MW_Host;
		   this.MW_Name = MetricConstants.MW_Name;
	   }
}

这是服务提供方（/returnlog）

package com.broadtech.clientmain.controller;

import java.util.ArrayList;
import java.util.List;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.client.RestTemplate;

import com.broadtech.middleware.metric.MetricLog;

@RestController
public class StartApp {

    @Autowired
    private RestTemplate template;
    
	@RequestMapping("/hello")
	public String hello() {
		return "eureka-client 服务提供方";
	}
	 
	@RequestMapping("/eatko")
	  public String index() {
		System.out.println("调用消费方的提供的 吃饭");
        return template.getForEntity("http://eureka-consumer/eat", String.class).getBody();
    }
    
	@RequestMapping("/returnlog")
	  public List indesx() {
		
		List li= new ArrayList();
		
		System.out.println("构造meticlog对象");
		for(int i=0;i<10; i++) {
			MetricLog ml=new MetricLog();
			ml.LId=1234343434l;
			ml.Log_Error="4";
			ml.Log_Level="3";
			ml.Web_Module_Name="质量业务监控模块";
			
			li.add(ml);	
		}
		System.out.println("li.size()= "+li.size());
		return li;
  }
  
}

服务消费方：

package com.broadtech.consumer.controller;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.Map;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.http.ResponseEntity;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.client.RestTemplate;

import com.broadtech.middleware.metric.MetricLog;
import com.fasterxml.jackson.databind.ObjectMapper;

import net.sf.json.JSONObject;

@Controller
@RestController
public class DealMonitorLog {

	private static final int List = 0;

	@Autowired
	RestTemplate restTemplate;

	static int a = 0;

	@RequestMapping("/ssg")
	public List tes() {
  
		while (true) {
			try {
				a++;
				Thread.sleep(5000);
				System.out.println("this is 第  " + a + " 次获取数据!");  
				ResponseEntity ec = restTemplate.getForEntity("http://hello/returnlog", String.class); 
				ObjectMapper mapper = new ObjectMapper();
				MetricLog[] mlog = mapper.readValue(ec.getBody(), MetricLog[].class);
				java.util.List mlogList = Arrays.asList(mlog);
				System.out.println("mlogList=" + mlogList.size());
				for (MetricLog a : mlogList) {
					System.out.println("循环打印list  MW_Name=" + a.MW_Name);
				} 
				 return  mlogList;
			} catch (Exception e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
		}
		 
	} 

}

这是自己的eureka 注册中心