Java基础之List内元素的排序性能对比

private ArrayList<StreamConfig> testCollectionSort(ArrayList<StreamConfig> lists) {
        Collections.sort(lists, new Comparator<StreamConfig>() {
            @Override
            public int compare(StreamConfig s1, StreamConfig s2) {
                return s2.getLostThreshold() - s1.getLostThreshold();
            }
        });
        return lists;
    }

@Data
@ToString
public class StreamConfig {

    /**
     * 主键
     */
    private Long id;

    /**
     * 分片检测(检测阈值)
     */
    private Integer detectRate;

    /**
     * 上报阈值
     */
    private Integer lostThreshold;

    /**
     * 上报周期(单位:秒)
     */
    private Integer reportRate;

    /**
     * 创建时间
     */
    private Date createTime;

    /**
     * 修改时间
     */
    private Date modifyTime;
}

 long startTime = System.currentTimeMillis();
    log.info("Collection.sort 排序开始时间为：{}", System.currentTimeMillis());
    ArrayList<StreamConfig> list = testCollectionSort(lists);
    long endTime = System.currentTimeMillis();
    log.info("Collection.sort 耗费总时间为：{} ms", endTime - startTime);

@Data
@ToString
public class StreamConfig implements Comparable<StreamConfig>{

    /**
     * 主键
     */
    private Long id;

    /**
     * 分片检测(检测阈值)
     */
    private Integer detectRate;

    /**
     * 上报阈值(丢失率大于多少不再上报)
     */
    private Integer lostThreshold;

    /**
     * 上报周期(单位:秒)
     */
    private Integer reportRate;

    /**
     * 创建时间
     */
    private Date createTime;

    /**
     * 修改时间
     */
    private Date modifyTime;

    /**
     * 备注
     */
    private String remark;

    /**
     * nodeCode
     */
    private String nodeCode;

    /**
     * 流媒体Id
     */
    private String unitId;

    @Override
    public int compareTo(StreamConfig o) {
        return this.getLostThreshold() - o.getLostThreshold();
    }
}

 long comparableStartTime = System.currentTimeMillis();
        Collections.sort(list3);
        long comparableEndTime = System.currentTimeMillis();
        log.info("Comparable 耗费总时间为：{}", comparableEndTime - comparableStartTime);

 long streamStartTime = System.currentTimeMillis();
        log.info("java 8 stream流式处理开启：{}", streamStartTime);
        List<StreamConfig> collect = list2.stream().sorted(Comparator.comparing(StreamConfig::getLostThreshold)).collect(Collectors.toList());
        log.info("java 8 stream流式所花时间为：{} ms", System.currentTimeMillis() - streamStartTime);

public String test() {
        ArrayList<StreamConfig> lists = new ArrayList<>(100000);
        for (int i = 0; i < 100000; i++) {
            StreamConfig streamConfig = new StreamConfig();
            streamConfig.setReportRate((int) (Math.random() * 10000));
            streamConfig.setLostThreshold((int) (Math.random() * 100000));
            streamConfig.setDetectRate((int) (Math.random() * 10000));
            streamConfig.setCreateTime(randomDate("2019-01-01", "2021-05-31"));
            streamConfig.setId(System.currentTimeMillis() + (int) (Math.random() * 100000));
            lists.add(streamConfig);
        }
        ArrayList<StreamConfig> list2 = new ArrayList<>(lists);
        ArrayList<StreamConfig> list3 = new ArrayList<>(lists);
        long startTime = System.currentTimeMillis();
        log.info("Collection.sort 排序开始时间为：{}", System.currentTimeMillis());
        ArrayList<StreamConfig> list = testCollectionSort(lists);
        long endTime = System.currentTimeMillis();
        log.info("Collection.sort 耗费总时间为：{} ms", endTime - startTime);

        log.info("Comparable 排序开始时间为：{}", System.currentTimeMillis());
        long comparableStartTime = System.currentTimeMillis();
        Collections.sort(list3);
        long comparableEndTime = System.currentTimeMillis();
        log.info("Comparable 耗费总时间为：{}", comparableEndTime - comparableStartTime);


        long streamStartTime = System.currentTimeMillis();
        log.info("java 8 stream流式处理开启：{}", streamStartTime);
        List<StreamConfig> collect = list2.stream().sorted(Comparator.comparing(StreamConfig::getLostThreshold).reversed()).collect(Collectors.toList());
        log.info("java 8 stream流式处理结束：{}", System.currentTimeMillis());
        log.info("java 8 stream流式所花时间为：{} ms", System.currentTimeMillis() - streamStartTime);
        return "success";
    }