springboot使用jmh基准测试评估json反序列化、实体转换的性能差异

1、背景

笔者经常把一些经常使用的数据放到redis缓存，方便程序进行读取。

比如按照不同的键名将数值存储到hash值类型中。示例如下

hash             hashkey   hashValue

snapshot          999          "{"id":999,"distId":999,"distName":"玄武区","confirm":7,"suspect":0,"dead":0,"heal":2,"weight":6.6,"level":"area","mapId":"c320100_2","updateTime":"2020-03-03 07:20:39"}"

snapshot1         999           {"confirm":7,"dead":0,"heal":2,"weight":6.6,"mapId":"c320100_2","updateTime":"2020-03-03 07:20:39","name":"玄武区"}

以上数据分别2052条

分别将snapshot1，snapshot转换成实体，现在将对他们进行基准测试，以评测两种存储方式的性能差异

2、基准测试

2个独立进程，分别依1次热身/热加载，批量执行20次，总计40次

2.1、snapshot1相关测试

这里用的实体转换框架是ModelMapper，官网：http://modelmapper.org/ 其性能比较高，主要用于实体属性之间的拷贝，

是笔者工作中项目实践中通过对比，选择到的这个框架。

maven依赖

<dependency>
   <groupId>org.modelmapper</groupId>
   <artifactId>modelmapper</artifactId>
   <version>0.7.7</version>
</dependency>

以下modelMapper转换成实体代码要加

modelMapper.getConfiguration().setMatchingStrategy(MatchingStrategies.STRICT);

不同的方法会影响基准测试的最终结果

@Benchmark
public void testMapToPojo()
{
    ModelMapper modelMapper = new ModelMapper();
    Map<String, Map> map = cacheService.getCacheMap("snapshot1");
    Map<String,SnapShot> result = new HashMap<>();

    for(Iterator<Map.Entry<String, Map>> it = map.entrySet().iterator(); it.hasNext();)
    {
        Map.Entry<String, Map> entry = it.next();

        String key = entry.getKey();
        SnapShot snapshot = modelMapper.map(entry, SnapShot.class);
        result.put(key, snapshot);
    }
}

    /**
     * 获得缓存的Map
     *
     * @param key
     * @return
     */
    @Override
    public <T> Map<String, T> getCacheMap(String key) {
        Map<String, T> map = redisTemplate.opsForHash().entries(key);
        return map;
    }

测试日志：

D:developjavajdk1.8.0_181injava.exe "-javaagent:D:Program FilesJetBrainsIntelliJ IDEA 2018.3.4libidea_rt.jar=52204:D:Program FilesJetBrainsIntelliJ IDEA 2018.3.4in" -Dfile.encoding=UTF-8 -classpath D:developjavajdk1.8.0_181jrelibcharsets.jar;D:developjavajdk1.8.0_181jrelibdeploy.jar;D:developjavajdk1.8.0_181jrelibextaccess-bridge-64.jar;D:developjavajdk1.8.0_181jrelibextcldrdata.jar;D:developjavajdk1.8.0_181jrelibextdnsns.jar;D:developjavajdk1.8.0_181jrelibextjaccess.jar;D:developjavajdk1.8.0_181jrelibextjfxrt.jar;D:developjavajdk1.8.0_181jrelibextlocaledata.jar;D:developjavajdk1.8.0_181jrelibext
ashorn.jar;D:developjavajdk1.8.0_181jrelibextsunec.jar;D:developjavajdk1.8.0_181jrelibextsunjce_provider.jar;D:developjavajdk1.8.0_181jrelibextsunmscapi.jar;D:developjavajdk1.8.0_181jrelibextsunpkcs11.jar;D:developjavajdk1.8.0_181jrelibextzipfs.jar;D:developjavajdk1.8.0_181jrelibjavaws.jar;D:developjavajdk1.8.0_181jrelibjce.jar;D:developjavajdk1.8.0_181jrelibjfr.jar;D:developjavajdk1.8.0_181jrelibjfxswt.jar;D:developjavajdk1.8.0_181jrelibjsse.jar;D:developjavajdk1.8.0_181jrelibmanagement-agent.jar;D:developjavajdk1.8.0_181jrelibplugin.jar;D:developjavajdk1.8.0_181jrelib
esources.jar;D:developjavajdk1.8.0_181jrelib
t.jar;E:projectjavaspringBootJmh	arget	est-classes;E:projectjavaspringBootJmh	argetclasses;D:developapache-maven-3.5.4
epoorgapachecommonscommons-pool22.5.0commons-pool2-2.5.0.jar;D:developapache-maven-3.5.4
epoorgspringframeworkootspring-boot-starter-cache2.2.4.RELEASEspring-boot-starter-cache-2.2.4.RELEASE.jar;D:developapache-maven-3.5.4
epoorgspringframeworkootspring-boot-starter2.2.4.RELEASEspring-boot-starter-2.2.4.RELEASE.jar;D:developapache-maven-3.5.4
epoorgspringframeworkootspring-boot2.2.4.RELEASEspring-boot-2.2.4.RELEASE.jar;D:developapache-maven-3.5.4
epoorgspringframeworkootspring-boot-autoconfigure2.2.4.RELEASEspring-boot-autoconfigure-2.2.4.RELEASE.jar;D:developapache-maven-3.5.4
epoorgspringframeworkootspring-boot-starter-logging2.2.4.RELEASEspring-boot-starter-logging-2.2.4.RELEASE.jar;D:developapache-maven-3.5.4
epochqoslogbacklogback-classic1.2.3logback-classic-1.2.3.jar;D:developapache-maven-3.5.4
epochqoslogbacklogback-core1.2.3logback-core-1.2.3.jar;D:developapache-maven-3.5.4
epoorgapachelogginglog4jlog4j-to-slf4j2.12.1log4j-to-slf4j-2.12.1.jar;D:developapache-maven-3.5.4
epoorgapachelogginglog4jlog4j-api2.12.1log4j-api-2.12.1.jar;D:developapache-maven-3.5.4
epoorgslf4jjul-to-slf4j1.7.30jul-to-slf4j-1.7.30.jar;D:developapache-maven-3.5.4
epojakartaannotationjakarta.annotation-api1.3.5jakarta.annotation-api-1.3.5.jar;D:developapache-maven-3.5.4
epoorgyamlsnakeyaml1.25snakeyaml-1.25.jar;D:developapache-maven-3.5.4
epoorgspringframeworkspring-context-support5.2.3.RELEASEspring-context-support-5.2.3.RELEASE.jar;D:developapache-maven-3.5.4
epoorgspringframeworkspring-beans5.2.3.RELEASEspring-beans-5.2.3.RELEASE.jar;D:developapache-maven-3.5.4
epoorgspringframeworkspring-context5.2.3.RELEASEspring-context-5.2.3.RELEASE.jar;D:developapache-maven-3.5.4
epoorgspringframeworkspring-expression5.2.3.RELEASEspring-expression-5.2.3.RELEASE.jar;D:developapache-maven-3.5.4
epoorgspringframeworkootspring-boot-starter-data-redis2.2.4.RELEASEspring-boot-starter-data-redis-2.2.4.RELEASE.jar;D:developapache-maven-3.5.4
epoorgspringframeworkdataspring-data-redis2.2.4.RELEASEspring-data-redis-2.2.4.RELEASE.jar;D:developapache-maven-3.5.4
epoorgspringframeworkdataspring-data-keyvalue2.2.4.RELEASEspring-data-keyvalue-2.2.4.RELEASE.jar;D:developapache-maven-3.5.4
epoorgspringframeworkdataspring-data-commons2.2.4.RELEASEspring-data-commons-2.2.4.RELEASE.jar;D:developapache-maven-3.5.4
epoorgspringframeworkspring-tx5.2.3.RELEASEspring-tx-5.2.3.RELEASE.jar;D:developapache-maven-3.5.4
epoorgspringframeworkspring-oxm5.2.3.RELEASEspring-oxm-5.2.3.RELEASE.jar;D:developapache-maven-3.5.4
epoorgspringframeworkspring-aop5.2.3.RELEASEspring-aop-5.2.3.RELEASE.jar;D:developapache-maven-3.5.4
epoorgslf4jslf4j-api1.7.30slf4j-api-1.7.30.jar;D:developapache-maven-3.5.4
epoiolettucelettuce-core5.2.1.RELEASElettuce-core-5.2.1.RELEASE.jar;D:developapache-maven-3.5.4
epoio
etty
etty-common4.1.45.Final
etty-common-4.1.45.Final.jar;D:developapache-maven-3.5.4
epoio
etty
etty-handler4.1.45.Final
etty-handler-4.1.45.Final.jar;D:developapache-maven-3.5.4
epoio
etty
etty-buffer4.1.45.Final
etty-buffer-4.1.45.Final.jar;D:developapache-maven-3.5.4
epoio
etty
etty-codec4.1.45.Final
etty-codec-4.1.45.Final.jar;D:developapache-maven-3.5.4
epoio
etty
etty-transport4.1.45.Final
etty-transport-4.1.45.Final.jar;D:developapache-maven-3.5.4
epoio
etty
etty-resolver4.1.45.Final
etty-resolver-4.1.45.Final.jar;D:developapache-maven-3.5.4
epoioprojectreactor
eactor-core3.3.2.RELEASE
eactor-core-3.3.2.RELEASE.jar;D:developapache-maven-3.5.4
epoorg
eactivestreams
eactive-streams1.0.3
eactive-streams-1.0.3.jar;D:developapache-maven-3.5.4
epocomdyuprojectprotostuffprotostuff-runtime1.1.3protostuff-runtime-1.1.3.jar;D:developapache-maven-3.5.4
epocomdyuprojectprotostuffprotostuff-collectionschema1.1.3protostuff-collectionschema-1.1.3.jar;D:developapache-maven-3.5.4
epocomdyuprojectprotostuffprotostuff-api1.0.8protostuff-api-1.0.8.jar;D:developapache-maven-3.5.4
epocomdyuprojectprotostuffprotostuff-core1.0.8protostuff-core-1.0.8.jar;D:developapache-maven-3.5.4
epoorgprojectlomboklombok1.18.10lombok-1.18.10.jar;D:developapache-maven-3.5.4
epoorgspringframeworkootspring-boot-starter-test2.2.4.RELEASEspring-boot-starter-test-2.2.4.RELEASE.jar;D:developapache-maven-3.5.4
epoorgspringframeworkootspring-boot-test2.2.4.RELEASEspring-boot-test-2.2.4.RELEASE.jar;D:developapache-maven-3.5.4
epoorgspringframeworkootspring-boot-test-autoconfigure2.2.4.RELEASEspring-boot-test-autoconfigure-2.2.4.RELEASE.jar;D:developapache-maven-3.5.4
epocomjaywayjsonpathjson-path2.4.0json-path-2.4.0.jar;D:developapache-maven-3.5.4
epo
etminidevjson-smart2.3json-smart-2.3.jar;D:developapache-maven-3.5.4
epo
etminidevaccessors-smart1.2accessors-smart-1.2.jar;D:developapache-maven-3.5.4
epoorgow2asmasm5.0.4asm-5.0.4.jar;D:developapache-maven-3.5.4
epojakartaxmlindjakarta.xml.bind-api2.3.2jakarta.xml.bind-api-2.3.2.jar;D:developapache-maven-3.5.4
epojakartaactivationjakarta.activation-api1.2.1jakarta.activation-api-1.2.1.jar;D:developapache-maven-3.5.4
epoorgjunitjupiterjunit-jupiter5.5.2junit-jupiter-5.5.2.jar;D:developapache-maven-3.5.4
epoorgjunitjupiterjunit-jupiter-api5.5.2junit-jupiter-api-5.5.2.jar;D:developapache-maven-3.5.4
epoorgapiguardianapiguardian-api1.1.0apiguardian-api-1.1.0.jar;D:developapache-maven-3.5.4
epoorgopentest4jopentest4j1.2.0opentest4j-1.2.0.jar;D:developapache-maven-3.5.4
epoorgjunitplatformjunit-platform-commons1.5.2junit-platform-commons-1.5.2.jar;D:developapache-maven-3.5.4
epoorgjunitjupiterjunit-jupiter-params5.5.2junit-jupiter-params-5.5.2.jar;D:developapache-maven-3.5.4
epoorgjunitjupiterjunit-jupiter-engine5.5.2junit-jupiter-engine-5.5.2.jar;D:developapache-maven-3.5.4
epoorgjunitplatformjunit-platform-engine1.5.2junit-platform-engine-1.5.2.jar;D:developapache-maven-3.5.4
epoorgmockitomockito-junit-jupiter3.1.0mockito-junit-jupiter-3.1.0.jar;D:developapache-maven-3.5.4
epoorgassertjassertj-core3.13.2assertj-core-3.13.2.jar;D:developapache-maven-3.5.4
epoorghamcresthamcrest2.1hamcrest-2.1.jar;D:developapache-maven-3.5.4
epoorgmockitomockito-core3.1.0mockito-core-3.1.0.jar;D:developapache-maven-3.5.4
epo
etytebuddybyte-buddy1.10.6byte-buddy-1.10.6.jar;D:developapache-maven-3.5.4
epo
etytebuddybyte-buddy-agent1.10.6byte-buddy-agent-1.10.6.jar;D:developapache-maven-3.5.4
epoorgobjenesisobjenesis2.6objenesis-2.6.jar;D:developapache-maven-3.5.4
epoorgskyscreamerjsonassert1.5.0jsonassert-1.5.0.jar;D:developapache-maven-3.5.4
epocomvaadinexternalgoogleandroid-json.0.20131108.vaadin1android-json-0.0.20131108.vaadin1.jar;D:developapache-maven-3.5.4
epoorgspringframeworkspring-core5.2.3.RELEASEspring-core-5.2.3.RELEASE.jar;D:developapache-maven-3.5.4
epoorgspringframeworkspring-jcl5.2.3.RELEASEspring-jcl-5.2.3.RELEASE.jar;D:developapache-maven-3.5.4
epoorgspringframeworkspring-test5.2.3.RELEASEspring-test-5.2.3.RELEASE.jar;D:developapache-maven-3.5.4
epoorgxmlunitxmlunit-core2.6.3xmlunit-core-2.6.3.jar;D:developapache-maven-3.5.4
epocomgoogleguavaguava20.0guava-20.0.jar;D:developapache-maven-3.5.4
epocomgooglecodegsongson2.8.4gson-2.8.4.jar;D:developapache-maven-3.5.4
epoorgmodelmappermodelmapper.7.7modelmapper-0.7.7.jar;D:developapache-maven-3.5.4
epoorgopenjdkjmhjmh-core1.21jmh-core-1.21.jar;D:developapache-maven-3.5.4
epo
etsfjopt-simplejopt-simple4.6jopt-simple-4.6.jar;D:developapache-maven-3.5.4
epoorgapachecommonscommons-math33.2commons-math3-3.2.jar;D:developapache-maven-3.5.4
epoorgopenjdkjmhjmh-generator-annprocess1.21jmh-generator-annprocess-1.21.jar;D:developapache-maven-3.5.4
epocomfasterxmljacksoncorejackson-annotations2.10.2jackson-annotations-2.10.2.jar;D:developapache-maven-3.5.4
epocomfasterxmljacksoncorejackson-databind2.10.2jackson-databind-2.10.2.jar;D:developapache-maven-3.5.4
epocomfasterxmljacksoncorejackson-core2.10.2jackson-core-2.10.2.jar;D:developapache-maven-3.5.4
epocomfasterxmljacksondatatypejackson-datatype-jsr3102.10.2jackson-datatype-jsr310-2.10.2.jar;D:developapache-maven-3.5.4
epocommons-beanutilscommons-beanutils1.9.3commons-beanutils-1.9.3.jar;D:developapache-maven-3.5.4
epocommons-loggingcommons-logging1.2commons-logging-1.2.jar;D:developapache-maven-3.5.4
epocommons-collectionscommons-collections3.2.2commons-collections-3.2.2.jar;D:developapache-maven-3.5.4
epojunitjunit4.12junit-4.12.jar;D:developapache-maven-3.5.4
epoorghamcresthamcrest-core2.1hamcrest-core-2.1.jar com.springboot.AppTest
# JMH version: 1.21
# VM version: JDK 1.8.0_181, Java HotSpot(TM) 64-Bit Server VM, 25.181-b13
# VM invoker: D:developjavajdk1.8.0_181jreinjava.exe
# VM options: -javaagent:D:Program FilesJetBrainsIntelliJ IDEA 2018.3.4libidea_rt.jar=52204:D:Program FilesJetBrainsIntelliJ IDEA 2018.3.4in -Dfile.encoding=UTF-8
# Warmup: 1 iterations, 10 s each
# Measurement: 20 iterations, 10 s each
# Timeout: 10 min per iteration
# Threads: 1 thread, will synchronize iterations
# Benchmark mode: Average time, time/op
# Benchmark: com.springboot.AppTest.testMapToPojo

# Run progress: 0.00% complete, ETA 00:07:00
# Fork: 1 of 2
# Warmup Iteration   1: LOGBACK: No context given for c.q.l.core.rolling.SizeAndTimeBasedRollingPolicy@999543437

  .   ____          _            __ _ _
 /\ / ___'_ __ _ _(_)_ __  __ _    
( ( )\___ | '_ | '_| | '_ / _` |    
 \/  ___)| |_)| | | | | || (_| |  ) ) ) )
  '  |____| .__|_| |_|_| |_\__, | / / / /
 =========|_|==============|___/=/_/_/_/
 :: Spring Boot ::        (v2.2.4.RELEASE)

2020-03-04 10:39:47.875  INFO 10892 --- [jo-jmh-worker-1] o.s.boot.SpringApplication               : Starting application on DESKTOP-AJTC6JT with PID 10892 (started by Administrator in E:projectjavaspringBootJmh)
2020-03-04 10:39:47.880  INFO 10892 --- [jo-jmh-worker-1] o.s.boot.SpringApplication               : No active profile set, falling back to default profiles: default
2020-03-04 10:39:48.380  INFO 10892 --- [jo-jmh-worker-1] .s.d.r.c.RepositoryConfigurationDelegate : Multiple Spring Data modules found, entering strict repository configuration mode!
2020-03-04 10:39:48.384  INFO 10892 --- [jo-jmh-worker-1] .s.d.r.c.RepositoryConfigurationDelegate : Bootstrapping Spring Data Redis repositories in DEFAULT mode.
2020-03-04 10:39:48.417  INFO 10892 --- [jo-jmh-worker-1] .s.d.r.c.RepositoryConfigurationDelegate : Finished Spring Data repository scanning in 19ms. Found 0 Redis repository interfaces.
2020-03-04 10:39:49.420  INFO 10892 --- [jo-jmh-worker-1] o.s.boot.SpringApplication               : Started application in 2.007 seconds (JVM running for 2.878)
2020-03-04 10:39:49.704  INFO 10892 --- [jo-jmh-worker-1] io.lettuce.core.EpollProvider            : Starting without optional epoll library
2020-03-04 10:39:49.705  INFO 10892 --- [jo-jmh-worker-1] io.lettuce.core.KqueueProvider           : Starting without optional kqueue library
4.977 ms/op
Iteration   1: 4.245 ms/op
Iteration   2: 4.212 ms/op
Iteration   3: 4.223 ms/op
Iteration   4: 4.372 ms/op
Iteration   5: 4.472 ms/op
Iteration   6: 4.559 ms/op
Iteration   7: 4.569 ms/op
Iteration   8: 4.393 ms/op
Iteration   9: 4.357 ms/op
Iteration  10: 4.218 ms/op
Iteration  11: 4.273 ms/op
Iteration  12: 4.372 ms/op
Iteration  13: 4.274 ms/op
Iteration  14: 4.194 ms/op
Iteration  15: 4.198 ms/op
Iteration  16: 4.177 ms/op
Iteration  17: 4.175 ms/op
Iteration  18: 4.180 ms/op
Iteration  19: 4.181 ms/op
Iteration  20: 4.185 ms/op

# Run progress: 50.00% complete, ETA 00:03:33
# Fork: 2 of 2
# Warmup Iteration   1: LOGBACK: No context given for c.q.l.core.rolling.SizeAndTimeBasedRollingPolicy@142500488

  .   ____          _            __ _ _
 /\ / ___'_ __ _ _(_)_ __  __ _    
( ( )\___ | '_ | '_| | '_ / _` |    
 \/  ___)| |_)| | | | | || (_| |  ) ) ) )
  '  |____| .__|_| |_|_| |_\__, | / / / /
 =========|_|==============|___/=/_/_/_/
 :: Spring Boot ::        (v2.2.4.RELEASE)

2020-03-04 10:43:21.156  INFO 5872 --- [jo-jmh-worker-1] o.s.boot.SpringApplication               : Starting application on DESKTOP-AJTC6JT with PID 5872 (started by Administrator in E:projectjavaspringBootJmh)
2020-03-04 10:43:21.159  INFO 5872 --- [jo-jmh-worker-1] o.s.boot.SpringApplication               : No active profile set, falling back to default profiles: default
2020-03-04 10:43:21.571  INFO 5872 --- [jo-jmh-worker-1] .s.d.r.c.RepositoryConfigurationDelegate : Multiple Spring Data modules found, entering strict repository configuration mode!
2020-03-04 10:43:21.574  INFO 5872 --- [jo-jmh-worker-1] .s.d.r.c.RepositoryConfigurationDelegate : Bootstrapping Spring Data Redis repositories in DEFAULT mode.
2020-03-04 10:43:21.600  INFO 5872 --- [jo-jmh-worker-1] .s.d.r.c.RepositoryConfigurationDelegate : Finished Spring Data repository scanning in 14ms. Found 0 Redis repository interfaces.
2020-03-04 10:43:22.461  INFO 5872 --- [jo-jmh-worker-1] o.s.boot.SpringApplication               : Started application in 1.646 seconds (JVM running for 2.298)
2020-03-04 10:43:22.720  INFO 5872 --- [jo-jmh-worker-1] io.lettuce.core.EpollProvider            : Starting without optional epoll library
2020-03-04 10:43:22.722  INFO 5872 --- [jo-jmh-worker-1] io.lettuce.core.KqueueProvider           : Starting without optional kqueue library
4.919 ms/op
Iteration   1: 4.240 ms/op
Iteration   2: 4.222 ms/op
Iteration   3: 4.188 ms/op
Iteration   4: 4.183 ms/op
Iteration   5: 4.188 ms/op
Iteration   6: 4.179 ms/op
Iteration   7: 4.210 ms/op
Iteration   8: 4.185 ms/op
Iteration   9: 4.409 ms/op
Iteration  10: 4.203 ms/op
Iteration  11: 4.219 ms/op
Iteration  12: 4.225 ms/op
Iteration  13: 4.333 ms/op
Iteration  14: 4.302 ms/op
Iteration  15: 4.240 ms/op
Iteration  16: 4.222 ms/op
Iteration  17: 4.297 ms/op
Iteration  18: 4.253 ms/op
Iteration  19: 4.243 ms/op
Iteration  20: 4.308 ms/op


Result "com.springboot.AppTest.testMapToPojo":
  4.267 ±(99.9%) 0.057 ms/op [Average]
  (min, avg, max) = (4.175, 4.267, 4.569), stdev = 0.101
  CI (99.9%): [4.210, 4.324] (assumes normal distribution)


# Run complete. Total time: 00:07:06

REMEMBER: The numbers below are just data. To gain reusable insights, you need to follow up on
why the numbers are the way they are. Use profilers (see -prof, -lprof), design factorial
experiments, perform baseline and negative tests that provide experimental control, make sure
the benchmarking environment is safe on JVM/OS/HW level, ask for reviews from the domain experts.
Do not assume the numbers tell you what you want them to tell.

Benchmark              Mode  Cnt  Score   Error  Units
AppTest.testMapToPojo  avgt   40  4.267 ± 0.057  ms/op

Process finished with exit code 0

结果：40次基准测试，最小（最理想）4.175毫秒，均值 4.267毫秒，最大值（最坏情况）4.569毫秒

2.2、snapshot测试

@Benchmark
public void testGetPojo()
{
    Map<String, SnapShot> map = cacheService.getCacheMap("snapshot", SnapShot.class);
}

@Override
public <T> Map<String, T> getCacheMap(String key, Class<T> clazz) {
    Map<String, String> raw = redisTemplate.opsForHash().entries(key);
    Map<String, T> map = Maps.newLinkedHashMapWithExpectedSize(raw.size());

    for (Map.Entry<String, String> entry : raw.entrySet()) {
        String hashKey = entry.getKey();
        String value = entry.getValue();
        map.put(hashKey, gson.fromJson(value, clazz));
    }
    return map;
}

测试日志：

D:developjavajdk1.8.0_181injava.exe "-javaagent:D:Program FilesJetBrainsIntelliJ IDEA 2018.3.4libidea_rt.jar=52899:D:Program FilesJetBrainsIntelliJ IDEA 2018.3.4in" -Dfile.encoding=UTF-8 -classpath D:developjavajdk1.8.0_181jrelibcharsets.jar;D:developjavajdk1.8.0_181jrelibdeploy.jar;D:developjavajdk1.8.0_181jrelibextaccess-bridge-64.jar;D:developjavajdk1.8.0_181jrelibextcldrdata.jar;D:developjavajdk1.8.0_181jrelibextdnsns.jar;D:developjavajdk1.8.0_181jrelibextjaccess.jar;D:developjavajdk1.8.0_181jrelibextjfxrt.jar;D:developjavajdk1.8.0_181jrelibextlocaledata.jar;D:developjavajdk1.8.0_181jrelibext
ashorn.jar;D:developjavajdk1.8.0_181jrelibextsunec.jar;D:developjavajdk1.8.0_181jrelibextsunjce_provider.jar;D:developjavajdk1.8.0_181jrelibextsunmscapi.jar;D:developjavajdk1.8.0_181jrelibextsunpkcs11.jar;D:developjavajdk1.8.0_181jrelibextzipfs.jar;D:developjavajdk1.8.0_181jrelibjavaws.jar;D:developjavajdk1.8.0_181jrelibjce.jar;D:developjavajdk1.8.0_181jrelibjfr.jar;D:developjavajdk1.8.0_181jrelibjfxswt.jar;D:developjavajdk1.8.0_181jrelibjsse.jar;D:developjavajdk1.8.0_181jrelibmanagement-agent.jar;D:developjavajdk1.8.0_181jrelibplugin.jar;D:developjavajdk1.8.0_181jrelib
esources.jar;D:developjavajdk1.8.0_181jrelib
t.jar;E:projectjavaspringBootJmh	arget	est-classes;E:projectjavaspringBootJmh	argetclasses;D:developapache-maven-3.5.4
epoorgapachecommonscommons-pool22.5.0commons-pool2-2.5.0.jar;D:developapache-maven-3.5.4
epoorgspringframeworkootspring-boot-starter-cache2.2.4.RELEASEspring-boot-starter-cache-2.2.4.RELEASE.jar;D:developapache-maven-3.5.4
epoorgspringframeworkootspring-boot-starter2.2.4.RELEASEspring-boot-starter-2.2.4.RELEASE.jar;D:developapache-maven-3.5.4
epoorgspringframeworkootspring-boot2.2.4.RELEASEspring-boot-2.2.4.RELEASE.jar;D:developapache-maven-3.5.4
epoorgspringframeworkootspring-boot-autoconfigure2.2.4.RELEASEspring-boot-autoconfigure-2.2.4.RELEASE.jar;D:developapache-maven-3.5.4
epoorgspringframeworkootspring-boot-starter-logging2.2.4.RELEASEspring-boot-starter-logging-2.2.4.RELEASE.jar;D:developapache-maven-3.5.4
epochqoslogbacklogback-classic1.2.3logback-classic-1.2.3.jar;D:developapache-maven-3.5.4
epochqoslogbacklogback-core1.2.3logback-core-1.2.3.jar;D:developapache-maven-3.5.4
epoorgapachelogginglog4jlog4j-to-slf4j2.12.1log4j-to-slf4j-2.12.1.jar;D:developapache-maven-3.5.4
epoorgapachelogginglog4jlog4j-api2.12.1log4j-api-2.12.1.jar;D:developapache-maven-3.5.4
epoorgslf4jjul-to-slf4j1.7.30jul-to-slf4j-1.7.30.jar;D:developapache-maven-3.5.4
epojakartaannotationjakarta.annotation-api1.3.5jakarta.annotation-api-1.3.5.jar;D:developapache-maven-3.5.4
epoorgyamlsnakeyaml1.25snakeyaml-1.25.jar;D:developapache-maven-3.5.4
epoorgspringframeworkspring-context-support5.2.3.RELEASEspring-context-support-5.2.3.RELEASE.jar;D:developapache-maven-3.5.4
epoorgspringframeworkspring-beans5.2.3.RELEASEspring-beans-5.2.3.RELEASE.jar;D:developapache-maven-3.5.4
epoorgspringframeworkspring-context5.2.3.RELEASEspring-context-5.2.3.RELEASE.jar;D:developapache-maven-3.5.4
epoorgspringframeworkspring-expression5.2.3.RELEASEspring-expression-5.2.3.RELEASE.jar;D:developapache-maven-3.5.4
epoorgspringframeworkootspring-boot-starter-data-redis2.2.4.RELEASEspring-boot-starter-data-redis-2.2.4.RELEASE.jar;D:developapache-maven-3.5.4
epoorgspringframeworkdataspring-data-redis2.2.4.RELEASEspring-data-redis-2.2.4.RELEASE.jar;D:developapache-maven-3.5.4
epoorgspringframeworkdataspring-data-keyvalue2.2.4.RELEASEspring-data-keyvalue-2.2.4.RELEASE.jar;D:developapache-maven-3.5.4
epoorgspringframeworkdataspring-data-commons2.2.4.RELEASEspring-data-commons-2.2.4.RELEASE.jar;D:developapache-maven-3.5.4
epoorgspringframeworkspring-tx5.2.3.RELEASEspring-tx-5.2.3.RELEASE.jar;D:developapache-maven-3.5.4
epoorgspringframeworkspring-oxm5.2.3.RELEASEspring-oxm-5.2.3.RELEASE.jar;D:developapache-maven-3.5.4
epoorgspringframeworkspring-aop5.2.3.RELEASEspring-aop-5.2.3.RELEASE.jar;D:developapache-maven-3.5.4
epoorgslf4jslf4j-api1.7.30slf4j-api-1.7.30.jar;D:developapache-maven-3.5.4
epoiolettucelettuce-core5.2.1.RELEASElettuce-core-5.2.1.RELEASE.jar;D:developapache-maven-3.5.4
epoio
etty
etty-common4.1.45.Final
etty-common-4.1.45.Final.jar;D:developapache-maven-3.5.4
epoio
etty
etty-handler4.1.45.Final
etty-handler-4.1.45.Final.jar;D:developapache-maven-3.5.4
epoio
etty
etty-buffer4.1.45.Final
etty-buffer-4.1.45.Final.jar;D:developapache-maven-3.5.4
epoio
etty
etty-codec4.1.45.Final
etty-codec-4.1.45.Final.jar;D:developapache-maven-3.5.4
epoio
etty
etty-transport4.1.45.Final
etty-transport-4.1.45.Final.jar;D:developapache-maven-3.5.4
epoio
etty
etty-resolver4.1.45.Final
etty-resolver-4.1.45.Final.jar;D:developapache-maven-3.5.4
epoioprojectreactor
eactor-core3.3.2.RELEASE
eactor-core-3.3.2.RELEASE.jar;D:developapache-maven-3.5.4
epoorg
eactivestreams
eactive-streams1.0.3
eactive-streams-1.0.3.jar;D:developapache-maven-3.5.4
epocomdyuprojectprotostuffprotostuff-runtime1.1.3protostuff-runtime-1.1.3.jar;D:developapache-maven-3.5.4
epocomdyuprojectprotostuffprotostuff-collectionschema1.1.3protostuff-collectionschema-1.1.3.jar;D:developapache-maven-3.5.4
epocomdyuprojectprotostuffprotostuff-api1.0.8protostuff-api-1.0.8.jar;D:developapache-maven-3.5.4
epocomdyuprojectprotostuffprotostuff-core1.0.8protostuff-core-1.0.8.jar;D:developapache-maven-3.5.4
epoorgprojectlomboklombok1.18.10lombok-1.18.10.jar;D:developapache-maven-3.5.4
epoorgspringframeworkootspring-boot-starter-test2.2.4.RELEASEspring-boot-starter-test-2.2.4.RELEASE.jar;D:developapache-maven-3.5.4
epoorgspringframeworkootspring-boot-test2.2.4.RELEASEspring-boot-test-2.2.4.RELEASE.jar;D:developapache-maven-3.5.4
epoorgspringframeworkootspring-boot-test-autoconfigure2.2.4.RELEASEspring-boot-test-autoconfigure-2.2.4.RELEASE.jar;D:developapache-maven-3.5.4
epocomjaywayjsonpathjson-path2.4.0json-path-2.4.0.jar;D:developapache-maven-3.5.4
epo
etminidevjson-smart2.3json-smart-2.3.jar;D:developapache-maven-3.5.4
epo
etminidevaccessors-smart1.2accessors-smart-1.2.jar;D:developapache-maven-3.5.4
epoorgow2asmasm5.0.4asm-5.0.4.jar;D:developapache-maven-3.5.4
epojakartaxmlindjakarta.xml.bind-api2.3.2jakarta.xml.bind-api-2.3.2.jar;D:developapache-maven-3.5.4
epojakartaactivationjakarta.activation-api1.2.1jakarta.activation-api-1.2.1.jar;D:developapache-maven-3.5.4
epoorgjunitjupiterjunit-jupiter5.5.2junit-jupiter-5.5.2.jar;D:developapache-maven-3.5.4
epoorgjunitjupiterjunit-jupiter-api5.5.2junit-jupiter-api-5.5.2.jar;D:developapache-maven-3.5.4
epoorgapiguardianapiguardian-api1.1.0apiguardian-api-1.1.0.jar;D:developapache-maven-3.5.4
epoorgopentest4jopentest4j1.2.0opentest4j-1.2.0.jar;D:developapache-maven-3.5.4
epoorgjunitplatformjunit-platform-commons1.5.2junit-platform-commons-1.5.2.jar;D:developapache-maven-3.5.4
epoorgjunitjupiterjunit-jupiter-params5.5.2junit-jupiter-params-5.5.2.jar;D:developapache-maven-3.5.4
epoorgjunitjupiterjunit-jupiter-engine5.5.2junit-jupiter-engine-5.5.2.jar;D:developapache-maven-3.5.4
epoorgjunitplatformjunit-platform-engine1.5.2junit-platform-engine-1.5.2.jar;D:developapache-maven-3.5.4
epoorgmockitomockito-junit-jupiter3.1.0mockito-junit-jupiter-3.1.0.jar;D:developapache-maven-3.5.4
epoorgassertjassertj-core3.13.2assertj-core-3.13.2.jar;D:developapache-maven-3.5.4
epoorghamcresthamcrest2.1hamcrest-2.1.jar;D:developapache-maven-3.5.4
epoorgmockitomockito-core3.1.0mockito-core-3.1.0.jar;D:developapache-maven-3.5.4
epo
etytebuddybyte-buddy1.10.6byte-buddy-1.10.6.jar;D:developapache-maven-3.5.4
epo
etytebuddybyte-buddy-agent1.10.6byte-buddy-agent-1.10.6.jar;D:developapache-maven-3.5.4
epoorgobjenesisobjenesis2.6objenesis-2.6.jar;D:developapache-maven-3.5.4
epoorgskyscreamerjsonassert1.5.0jsonassert-1.5.0.jar;D:developapache-maven-3.5.4
epocomvaadinexternalgoogleandroid-json.0.20131108.vaadin1android-json-0.0.20131108.vaadin1.jar;D:developapache-maven-3.5.4
epoorgspringframeworkspring-core5.2.3.RELEASEspring-core-5.2.3.RELEASE.jar;D:developapache-maven-3.5.4
epoorgspringframeworkspring-jcl5.2.3.RELEASEspring-jcl-5.2.3.RELEASE.jar;D:developapache-maven-3.5.4
epoorgspringframeworkspring-test5.2.3.RELEASEspring-test-5.2.3.RELEASE.jar;D:developapache-maven-3.5.4
epoorgxmlunitxmlunit-core2.6.3xmlunit-core-2.6.3.jar;D:developapache-maven-3.5.4
epocomgoogleguavaguava20.0guava-20.0.jar;D:developapache-maven-3.5.4
epocomgooglecodegsongson2.8.4gson-2.8.4.jar;D:developapache-maven-3.5.4
epoorgmodelmappermodelmapper.7.7modelmapper-0.7.7.jar;D:developapache-maven-3.5.4
epoorgopenjdkjmhjmh-core1.21jmh-core-1.21.jar;D:developapache-maven-3.5.4
epo
etsfjopt-simplejopt-simple4.6jopt-simple-4.6.jar;D:developapache-maven-3.5.4
epoorgapachecommonscommons-math33.2commons-math3-3.2.jar;D:developapache-maven-3.5.4
epoorgopenjdkjmhjmh-generator-annprocess1.21jmh-generator-annprocess-1.21.jar;D:developapache-maven-3.5.4
epocomfasterxmljacksoncorejackson-annotations2.10.2jackson-annotations-2.10.2.jar;D:developapache-maven-3.5.4
epocomfasterxmljacksoncorejackson-databind2.10.2jackson-databind-2.10.2.jar;D:developapache-maven-3.5.4
epocomfasterxmljacksoncorejackson-core2.10.2jackson-core-2.10.2.jar;D:developapache-maven-3.5.4
epocomfasterxmljacksondatatypejackson-datatype-jsr3102.10.2jackson-datatype-jsr310-2.10.2.jar;D:developapache-maven-3.5.4
epocommons-beanutilscommons-beanutils1.9.3commons-beanutils-1.9.3.jar;D:developapache-maven-3.5.4
epocommons-loggingcommons-logging1.2commons-logging-1.2.jar;D:developapache-maven-3.5.4
epocommons-collectionscommons-collections3.2.2commons-collections-3.2.2.jar;D:developapache-maven-3.5.4
epojunitjunit4.12junit-4.12.jar;D:developapache-maven-3.5.4
epoorghamcresthamcrest-core2.1hamcrest-core-2.1.jar com.springboot.AppTest
# JMH version: 1.21
# VM version: JDK 1.8.0_181, Java HotSpot(TM) 64-Bit Server VM, 25.181-b13
# VM invoker: D:developjavajdk1.8.0_181jreinjava.exe
# VM options: -javaagent:D:Program FilesJetBrainsIntelliJ IDEA 2018.3.4libidea_rt.jar=52899:D:Program FilesJetBrainsIntelliJ IDEA 2018.3.4in -Dfile.encoding=UTF-8
# Warmup: 1 iterations, 10 s each
# Measurement: 20 iterations, 10 s each
# Timeout: 10 min per iteration
# Threads: 1 thread, will synchronize iterations
# Benchmark mode: Average time, time/op
# Benchmark: com.springboot.AppTest.testGetPojo

# Run progress: 0.00% complete, ETA 00:07:00
# Fork: 1 of 2
# Warmup Iteration   1: LOGBACK: No context given for c.q.l.core.rolling.SizeAndTimeBasedRollingPolicy@1051164110

  .   ____          _            __ _ _
 /\ / ___'_ __ _ _(_)_ __  __ _    
( ( )\___ | '_ | '_| | '_ / _` |    
 \/  ___)| |_)| | | | | || (_| |  ) ) ) )
  '  |____| .__|_| |_|_| |_\__, | / / / /
 =========|_|==============|___/=/_/_/_/
 :: Spring Boot ::        (v2.2.4.RELEASE)

2020-03-04 11:08:57.181  INFO 12868 --- [jo-jmh-worker-1] o.s.boot.SpringApplication               : Starting application on DESKTOP-AJTC6JT with PID 12868 (started by Administrator in E:projectjavaspringBootJmh)
2020-03-04 11:08:57.185  INFO 12868 --- [jo-jmh-worker-1] o.s.boot.SpringApplication               : No active profile set, falling back to default profiles: default
2020-03-04 11:08:57.710  INFO 12868 --- [jo-jmh-worker-1] .s.d.r.c.RepositoryConfigurationDelegate : Multiple Spring Data modules found, entering strict repository configuration mode!
2020-03-04 11:08:57.712  INFO 12868 --- [jo-jmh-worker-1] .s.d.r.c.RepositoryConfigurationDelegate : Bootstrapping Spring Data Redis repositories in DEFAULT mode.
2020-03-04 11:08:57.746  INFO 12868 --- [jo-jmh-worker-1] .s.d.r.c.RepositoryConfigurationDelegate : Finished Spring Data repository scanning in 21ms. Found 0 Redis repository interfaces.
2020-03-04 11:08:58.849  INFO 12868 --- [jo-jmh-worker-1] o.s.boot.SpringApplication               : Started application in 2.147 seconds (JVM running for 3.097)
2020-03-04 11:08:59.086  INFO 12868 --- [jo-jmh-worker-1] io.lettuce.core.EpollProvider            : Starting without optional epoll library
2020-03-04 11:08:59.087  INFO 12868 --- [jo-jmh-worker-1] io.lettuce.core.KqueueProvider           : Starting without optional kqueue library
8.041 ms/op
Iteration   1: 7.019 ms/op
Iteration   2: 7.032 ms/op
Iteration   3: 7.008 ms/op
Iteration   4: 7.081 ms/op
Iteration   5: 6.997 ms/op
Iteration   6: 6.958 ms/op
Iteration   7: 6.925 ms/op
Iteration   8: 6.935 ms/op
Iteration   9: 6.943 ms/op
Iteration  10: 6.940 ms/op
Iteration  11: 6.948 ms/op
Iteration  12: 6.956 ms/op
Iteration  13: 7.033 ms/op
Iteration  14: 6.969 ms/op
Iteration  15: 6.964 ms/op
Iteration  16: 6.962 ms/op
Iteration  17: 6.962 ms/op
Iteration  18: 6.955 ms/op
Iteration  19: 6.959 ms/op
Iteration  20: 6.973 ms/op

# Run progress: 50.00% complete, ETA 00:03:33
# Fork: 2 of 2
# Warmup Iteration   1: LOGBACK: No context given for c.q.l.core.rolling.SizeAndTimeBasedRollingPolicy@1741951395

  .   ____          _            __ _ _
 /\ / ___'_ __ _ _(_)_ __  __ _    
( ( )\___ | '_ | '_| | '_ / _` |    
 \/  ___)| |_)| | | | | || (_| |  ) ) ) )
  '  |____| .__|_| |_|_| |_\__, | / / / /
 =========|_|==============|___/=/_/_/_/
 :: Spring Boot ::        (v2.2.4.RELEASE)

2020-03-04 11:12:30.673  INFO 12292 --- [jo-jmh-worker-1] o.s.boot.SpringApplication               : Starting application on DESKTOP-AJTC6JT with PID 12292 (started by Administrator in E:projectjavaspringBootJmh)
2020-03-04 11:12:30.676  INFO 12292 --- [jo-jmh-worker-1] o.s.boot.SpringApplication               : No active profile set, falling back to default profiles: default
2020-03-04 11:12:31.092  INFO 12292 --- [jo-jmh-worker-1] .s.d.r.c.RepositoryConfigurationDelegate : Multiple Spring Data modules found, entering strict repository configuration mode!
2020-03-04 11:12:31.094  INFO 12292 --- [jo-jmh-worker-1] .s.d.r.c.RepositoryConfigurationDelegate : Bootstrapping Spring Data Redis repositories in DEFAULT mode.
2020-03-04 11:12:31.121  INFO 12292 --- [jo-jmh-worker-1] .s.d.r.c.RepositoryConfigurationDelegate : Finished Spring Data repository scanning in 15ms. Found 0 Redis repository interfaces.
2020-03-04 11:12:32.013  INFO 12292 --- [jo-jmh-worker-1] o.s.boot.SpringApplication               : Started application in 1.678 seconds (JVM running for 2.34)
2020-03-04 11:12:32.297  INFO 12292 --- [jo-jmh-worker-1] io.lettuce.core.EpollProvider            : Starting without optional epoll library
2020-03-04 11:12:32.299  INFO 12292 --- [jo-jmh-worker-1] io.lettuce.core.KqueueProvider           : Starting without optional kqueue library
7.919 ms/op
Iteration   1: 7.405 ms/op
Iteration   2: 7.021 ms/op
Iteration   3: 7.133 ms/op
Iteration   4: 6.975 ms/op
Iteration   5: 6.915 ms/op
Iteration   6: 6.898 ms/op
Iteration   7: 6.934 ms/op
Iteration   8: 6.939 ms/op
Iteration   9: 6.909 ms/op
Iteration  10: 6.839 ms/op
Iteration  11: 7.037 ms/op
Iteration  12: 7.005 ms/op
Iteration  13: 7.044 ms/op
Iteration  14: 7.009 ms/op
Iteration  15: 6.941 ms/op
Iteration  16: 6.860 ms/op
Iteration  17: 6.848 ms/op
Iteration  18: 6.869 ms/op
Iteration  19: 6.893 ms/op
Iteration  20: 6.874 ms/op


Result "com.springboot.AppTest.testGetPojo":
  6.972 ±(99.9%) 0.053 ms/op [Average]
  (min, avg, max) = (6.839, 6.972, 7.405), stdev = 0.094
  CI (99.9%): [6.919, 7.025] (assumes normal distribution)


# Run complete. Total time: 00:07:07

REMEMBER: The numbers below are just data. To gain reusable insights, you need to follow up on
why the numbers are the way they are. Use profilers (see -prof, -lprof), design factorial
experiments, perform baseline and negative tests that provide experimental control, make sure
the benchmarking environment is safe on JVM/OS/HW level, ask for reviews from the domain experts.
Do not assume the numbers tell you what you want them to tell.

Benchmark            Mode  Cnt  Score   Error  Units
AppTest.testGetPojo  avgt   40  6.972 ± 0.053  ms/op

Process finished with exit code 0

结果：最小值：6.839（最理想值）毫秒, 均值6.972 最大值(最坏情况)7.405

3、测试数据

3.1、数据存储方式

{"confirm":7,"dead":0,"heal":2,"weight":6.6,"mapId":"c320100_2","updateTime":"2020-03-03 07:20:39","name":"玄武区"}

3.1.1 存到redis缓存中，取出来时候是在java这边是以LinkedHashMap（基于链表方式存储的Hash）

"{"id":999,"distId":999,"distName":"玄武区","confirm":7,"suspect":0,"dead":0,"heal":2,"weight":6.6,"level":"area","mapId":"c320100_2","updateTime":"2020-03-03 07:20:39"}"

3.1.2、从内存中取出来，在java这里是以String存储的

测试代码

RedisTest.java

package com.springboot;

import com.fasterxml.jackson.databind.ObjectMapper;
import com.google.gson.Gson;
import com.springboot.entity.SnapShot;
import com.springboot.service.CacheService;
import org.junit.Before;
import org.junit.jupiter.api.Test;
import org.modelmapper.ModelMapper;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.context.ConfigurableApplicationContext;

import java.util.Iterator;
import java.util.Map;
@SpringBootTest(classes = App.class)
public class RedisTest {
    private ConfigurableApplicationContext context;

    final Gson gson = new Gson();
    ObjectMapper mapper = new ObjectMapper();

    ModelMapper modelMapper = new ModelMapper();

    @Autowired
    CacheService cacheService;


    /**
     * setup初始化容器的时候只执行一次
     */
    @Before
    public void init(){
        context = SpringApplication.run(App.class);
        cacheService = context.getBean(CacheService.class);
    }

    @Test
    public void testGetPojo()
    {
        Map<String, SnapShot> map = cacheService.getCacheMap("snapshot", SnapShot.class);
        System.out.println(map);
        cacheService.setCacheMap("snapshot1",map);
    }

    @Test
    public void testMapToPojo()
    {
        Map<String, Map> map = cacheService.getCacheMap("snapshot1");

        for(Iterator<Map.Entry<String, Map>> it = map.entrySet().iterator();it.hasNext();)
        {
            Map.Entry<String, Map> entry = it.next();

            SnapShot snapshot = modelMapper.map(entry, SnapShot.class);
        }
    }

}

4、结论

不使用转义字符的 json形式

{"confirm":7,"dead":0,"heal":2,"weight":6.6,"mapId":"c320100_2","updateTime":"2020-03-03 07:20:39","name":"玄武区"}

比使用转义字符的json：

"{"id":999,"distId":999,"distName":"玄武区","confirm":7,"suspect":0,"dead":0,"heal":2,"weight":6.6,"level":"area","mapId":"c320100_2","updateTime":"2020-03-03 07:20:39"}"

转换成实体快。

同样的配置机器，使用不带转义字符的json形式存储，然后再用modelMapper反序列化实体，均值快2.705毫秒，速度提升2.705/6.972=38.798%

笔者最终把上面的<T> Map<String, T> getCacheMap(String key, Class<T> clazz);重构成以下代码

    @Override
    public <T> Map<String, T> getCacheMap(String key, Class<T> clazz) {
        Map<String, Object> raw = redisTemplate.opsForHash().entries(key);
        Map<String, T> map = Maps.newLinkedHashMapWithExpectedSize(raw.size());

        for (Map.Entry<String, Object> entry : raw.entrySet()) {
            final String hashKey = entry.getKey();
            final Object value = entry.getValue();

            /***
             * 假设redis中hash值类型存储的hashValue是不带转义字符的json，形如:
             * <code>{"confirm":7,"dead":0,"heal":2,"weight":6.6,"mapId":"c320100_2","updateTime":"2020-03-03 07:20:39","name":"玄武区"}</code>
             * spring redis template(jedis)会把他转换成LinkedHashMap，这个时候利用ModelMapper将其转换成目标实体类型，速度比带转义字符类型快38.798%
            * */
            if(value instanceof Map)
            {
                map.put(hashKey,modelMapper.map(value, clazz));
                //处理带转义字符类型的json字符串
                //"{"id":999,"distId":999,"name":"玄武区","confirm":7,"suspect":0,"dead":0,"heal":2,"weight":6.6,"level":"area","mapId":"c320100_2","updateTime":"2020-03-03 07:20:39"}"
            }else if(value instanceof String) {
                map.put(hashKey, gson.fromJson((String)value, clazz));
            }
        }
        return map;
    }

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原文地址：https://www.cnblogs.com/passedbylove/p/12408801.html