java中实现实例复制

小咪咪 2024-04-06 14:10 12阅读 0赞

### 1、工具类如下： ###

package com.merit.performancemonitoring.util;
    
    import lombok.extern.slf4j.Slf4j;
    
    import java.lang.reflect.Field;
    
    @Slf4j
    public class BeanCopyUtil {
        
        /**
         * 相同对象合并，将原对象的非空属性的值赋值给目标对象
         *
         * @param origin      源对象
         * @param destination 目标对象
         * @param <T>         对象的类型
         */
        public static <T> void merge(T origin, T destination) {
        
            if (origin == null || destination == null) {
        
                return;
            }
            if (!origin.getClass().equals(destination.getClass())) {
        
                return;
            }
            Field[] fields = origin.getClass().getDeclaredFields();
            for (Field field : fields) {
        
                field.setAccessible(true);
                try {
        
                    Object value = field.get(origin);
                    if (null != value) {
        
                        field.set(destination, value);
                    }
                } catch (IllegalAccessException e) {
        
                    log.error("访问对象异常", e);
                }
                field.setAccessible(false);
            }
        }
    }

### 2、具体实例： ###

private List<RdsPerformanceEntity> makeupData(DescribeDBInstancePerformanceResponse response) {
        
            Map<String, String> maps = rdsConfig.getDbInstanceIpMaps();
            SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
            SimpleDateFormat sdf = new SimpleDateFormat("yyyyMMddHHmmss");
            List<RdsPerformanceEntity> rdsList = new ArrayList<>();
            RdsPerformanceEntity rds = RdsPerformanceEntity.builder()
                    .requestId(response.getRequestId())
                    .dBInstanceId(response.getDBInstanceId())
                    .engine(response.getEngine())
                    .startTime(response.getStartTime())
                    .endTime(response.getEndTime())
                    .build();
            for (DescribeDBInstancePerformanceResponse.PerformanceKey performanceKey : response.getPerformanceKeys()) {
        
                RdsPerformanceEntity rdsKey = RdsPerformanceEntity.builder().build();
                BeanCopyUtil.merge(rds, rdsKey);
                rdsKey.setKey(performanceKey.getKey());
                rdsKey.setUnit(performanceKey.getUnit());
                rdsKey.setValueFormat(performanceKey.getValueFormat());
                for (DescribeDBInstancePerformanceResponse.PerformanceKey.PerformanceValue pValue : performanceKey.getValues()) {
        
                    RdsPerformanceEntity rdsValue = RdsPerformanceEntity.builder().build();
                    BeanCopyUtil.merge(rdsKey, rdsValue);
                    rdsValue.setValue(pValue.getValue());
                    rdsValue.setDate(pValue.getDate());
                    Date date = new Date();
                    rdsValue.setCreateTime(df.format(date));
                    String hostIp = maps.get(rdsValue.getDBInstanceId());
                    if (hostIp == null) {
        
                        hostIp = "null";
                    }
                    rdsValue.setHostIp(hostIp);
                    rdsValue.setId(sdf.format(date) + hostIp);
                    rdsList.add(rdsValue);
                }
            }
            return rdsList;
        }