java.util.LinkedHashMap$Entry cannot be cast to java.util.Map

今天从ArrayList中取Map报了这个错误,我分析原因是ArrayList初始化的时候没有给定队形类型导致List中放的是默认的LinkHashMap$Entry,所以你再想从List中取出Map时就会报这个错误。初始化应入下代码:

// 传到前台的List
ArrayList> topList = new ArrayList>();
// 要放入的值
Map tempMap = new HashMap<>();
tempMap.put("a","aa");
topList.add(tempMap);


从List中取值:

ArrayList topList = new ArrayList();
for(int i=0;i< resList.size();i++){
    Map,Object> map = (Map) resList.get(i);
    for (Map.Entry,Object> entry : map.entrySet()) {
        ApiResponse apiResponse = new ApiResponse();
        apiResponse.setMessage(entry.getKey());
        apiResponse.setData(entry.getValue());

        topList.add(apiResponse);
    }
}
这样亲测不会报错

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