记一次Java List重复数据的问题

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贴上原代码

List<ReportDataModel.Data> data = new ArrayList<>();ReportDataModel.Data reportData = = new ReportDataModel().new Data();                    for (TimeAndValue timeAndValue : timeAndValueList) {                        reportData.setName(indexType.getName());                        Calendar cal = Calendar.getInstance();                        cal.setTimeInMillis(timeAndValue.getTime());                        if (model.getType() == QUERY_TYPE_YEAR) {// 年                            reportData.setTime(SDF_YEAR.format(cal.getTime()));                        } else if (model.getType() == QUERY_TYPE_MONTH) {// 月                            reportData.setTime(SDF_YEAR_MONTH.format(cal.getTime()));                        } else if (model.getType() == QUERY_TYPE_WEEK) {// 周                            reportData.setTime(cal.get(Calendar.YEAR) + "-" + cal.get(Calendar.DAY_OF_WEEK));                        } else if (model.getType() == QUERY_TYPE_DAY) {// 日                            reportData.setTime(SDF_YEAR_MONTH_DAY.format(cal.getTime()));                        } else if (model.getType() == QUERY_TYPE_HOUR) {// 小时                            reportData.setTime(SDF_YEAR_MONTH_DAY_HOUR.format(cal.getTime()));                        }                        if (timeAndValue.isDouble()) {                            reportData.setData(timeAndValue.getDoubleValue());                        } else if (timeAndValue.isLong()) {                            reportData.setData((double) timeAndValue.getLongValue());                        }                        data.add(reportData);                    }

贴上改正后的代码

List<ReportDataModel.Data> data = new ArrayList<>();ReportDataModel.Data reportData = null;                    for (TimeAndValue timeAndValue : timeAndValueList) {                        reportData = new ReportDataModel().new Data();                        reportData.setName(indexType.getName());                        Calendar cal = Calendar.getInstance();                        cal.setTimeInMillis(timeAndValue.getTime());                        if (model.getType() == QUERY_TYPE_YEAR) {// 年                            reportData.setTime(SDF_YEAR.format(cal.getTime()));                        } else if (model.getType() == QUERY_TYPE_MONTH) {// 月                            reportData.setTime(SDF_YEAR_MONTH.format(cal.getTime()));                        } else if (model.getType() == QUERY_TYPE_WEEK) {// 周                            reportData.setTime(cal.get(Calendar.YEAR) + "-" + cal.get(Calendar.DAY_OF_WEEK));                        } else if (model.getType() == QUERY_TYPE_DAY) {// 日                            reportData.setTime(SDF_YEAR_MONTH_DAY.format(cal.getTime()));                        } else if (model.getType() == QUERY_TYPE_HOUR) {// 小时                            reportData.setTime(SDF_YEAR_MONTH_DAY_HOUR.format(cal.getTime()));                        }                        if (timeAndValue.isDouble()) {                            reportData.setData(timeAndValue.getDoubleValue());                        } else if (timeAndValue.isLong()) {                            reportData.setData((double) timeAndValue.getLongValue());                        }                        data.add(reportData);                    }

请大家注意看原代码这一行：ReportDataModel.Data reportData = = new ReportDataModel().new Data(); 以及对比新代码ReportDataModel.Data reportData = null;然后再for循环中以及实例化对象，原代码相当于重复操作内存中的一个对象，固然出现了重复数据，记下来自己挖的坑自己填起来。

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