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使用 jdk 1.9 Callback 接口，提示我找不到

0

1

class="cursor-pointer"> 详细描述

class="cursor-pointer"> 错误截图

该问题已被官方收录

在使用redis缓存时如何将业务逻辑与缓存之间解耦

1

缓存相关

class="cursor-pointer"> 详细描述

class="cursor-pointer"> 源码

   @Override
    public User getUserById(int id) throws Exception {
        //find  cache
        Object object = jedisCache.get("user"+id);
        // if exist,return
        if (object!=null){
            return (User)object;
        }
        // if not exist,find user
        User user = userDAO.getUserById(id);
        jedisCache.set("user"+id,user);
        return user;
    }

该问题已被官方收录

redis序列化问题

0

1

redis

class="cursor-pointer"> 详细描述

class="cursor-pointer"> 错误截图

class="cursor-pointer"> 源码

  @Override
    //单条查询
    public User findUserById(int userId) {
        ValueOperations<String, Object> vos = redisTemplate.opsForValue();

        User user = null;
        if ("".equals(vos.get(String.valueOf(userId)))){

//            (redisTemplate.opsForValue().get(String.valueOf(userId))==null)
            logger.info("\n从缓存返回空值");
            return user;
        }

        try {

            if (vos.get(String.valueOf(userId)) != null) {
                logger.info("\n" + "从缓存中查询单条数据");
                user = (User) vos.get(String.valueOf(userId));
            } else {
                logger.info("\n" + "从数据库中查询单条数据");
                user = userDao.findUserById(userId);
                if (user != null) {
                    vos.set(String.valueOf(userId), user);
                    logger.info("\n" + "新增单条缓存数据:" + vos.get(String.valueOf(userId)));
                } else {
                    vos.set(String.valueOf(userId),"", 60,TimeUnit.SECONDS);
                    logger.info("\n" + "将空值存到缓存");
                }
            }
        } catch (Throwable t) {
            t.printStackTrace();
        }
        return user;


    }

该问题已被官方收录

添加redis缓存，结果报错

1

redis

class="cursor-pointer"> 详细描述

class="cursor-pointer"> 错误截图

class="cursor-pointer"> 源码

 @Override
    public void saveStudentRedis(Student student){
        ValueOperations<String,Student> valueOperations = redisTemplate.opsForValue();
        valueOperations.set(student.getName(),student);
        addToList(student);
    }

org.springframework.data.redis.serializer.SerializationException: Cannot serialize; nested exception is org.springframework.core.serializer.support.SerializationFailedException: Failed to serialize object using DefaultSerializer; nested exception is java.lang.IllegalArgumentException: DefaultSerializer requires a Serializable payload but received an object of type [com.alibaba.model.Student]

at org.springframework.data.redis.serializer.JdkSerializationRedisSerializer.serialize(JdkSerializationRedisSerializer.java:93)
	at org.springframework.data.redis.core.AbstractOperations.rawValue(AbstractOperations.java:117)
	at org.springframework.data.redis.core.DefaultValueOperations.set(DefaultValueOperations.java:168)
	at com.alibaba.services.Impl.StudentServiceImpl.saveStudentRedis(StudentServiceImpl.java:66)
	at com.alibaba.Impl.StudentServiceImplTest.saveRedis(StudentServiceImplTest.java:73)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:498)
	at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:50)
	at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)
	at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:47)
	at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)
	at org.springframework.test.context.junit4.statements.RunBeforeTestMethodCallbacks.evaluate(RunBeforeTestMethodCallbacks.java:75)
	at org.springframework.test.context.junit4.statements.RunAfterTestMethodCallbacks.evaluate(RunAfterTestMethodCallbacks.java:86)
	at org.springframework.test.context.junit4.statements.SpringRepeat.evaluate(SpringRepeat.java:84)
	at org.junit.runners.ParentRunner.runLeaf(ParentRunner.java:325)
	at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:252)
	at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:94)
	at org.junit.runners.ParentRunner$3.run(ParentRunner.java:290)
	at org.junit.runners.ParentRunner$1.schedule(ParentRunner.java:71)
	at org.junit.runners.ParentRunner.runChildren(ParentRunner.java:288)
	at org.junit.runners.ParentRunner.access$000(ParentRunner.java:58)
	at org.junit.runners.ParentRunner$2.evaluate(ParentRunner.java:268)
	at org.springframework.test.context.junit4.statements.RunBeforeTestClassCallbacks.evaluate(RunBeforeTestClassCallbacks.java:61)
	at org.springframework.test.context.junit4.statements.RunAfterTestClassCallbacks.evaluate(RunAfterTestClassCallbacks.java:70)
	at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
	at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.run(SpringJUnit4ClassRunner.java:191)
	at org.junit.runner.JUnitCore.run(JUnitCore.java:137)
	at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java:68)
	at com.intellij.rt.execution.junit.IdeaTestRunner$Repeater.startRunnerWithArgs(IdeaTestRunner.java:47)
	at com.intellij.rt.execution.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:242)
	at com.intellij.rt.execution.junit.JUnitStarter.main(JUnitStarter.java:70)
Caused by: org.springframework.core.serializer.support.SerializationFailedException: Failed to serialize object using DefaultSerializer; nested exception is java.lang.IllegalArgumentException: DefaultSerializer requires a Serializable payload but received an object of type [com.alibaba.model.Student]
	at org.springframework.core.serializer.support.SerializingConverter.convert(SerializingConverter.java:68)
	at org.springframework.core.serializer.support.SerializingConverter.convert(SerializingConverter.java:35)
	at org.springframework.data.redis.serializer.JdkSerializationRedisSerializer.serialize(JdkSerializationRedisSerializer.java:91)
	... 32 more
Caused by: java.lang.IllegalArgumentException: DefaultSerializer requires a Serializable payload but received an object of type [com.alibaba.model.Student]
	at org.springframework.core.serializer.DefaultSerializer.serialize(DefaultSerializer.java:43)
	at org.springframework.core.serializer.support.SerializingConverter.convert(SerializingConverter.java:63)
	... 34 more

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使用Jmeter压测的时候报错

1

压测

class="cursor-pointer"> 详细描述

class="cursor-pointer"> 错误截图

该问题已被官方收录

win10 中的 memcached每次重启都连接不上

1

memcache

class="cursor-pointer"> 详细描述

class="cursor-pointer"> 错误截图

该问题已被官方收录

无法识别properties文件

1

缓存相关

class="cursor-pointer"> 详细描述

做任务六的时候需要加载到mencached的配置文件，然后在spring-mybatis里的xml文件添加 <import resource="app-context-xmemcached.xml"/>，但是无法加载到xml相关的properties文件

<bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
        <property name="dataSource" ref="dataSource"/>
        
        <property name="mapperLocations" value="classpath:UserMapper.xml"/>
    </bean>

class="cursor-pointer"> 错误截图

该问题已被官方收录

缓存

1

缓存相关

class="cursor-pointer"> 详细描述

class="cursor-pointer"> 错误截图

该问题已被官方收录

redis在存储100条数据时报错

0

1

redis

class="cursor-pointer"> 详细描述

class="cursor-pointer"> 错误截图

class="cursor-pointer"> 源码

  @Test
    public void zsetAdd() {
//        spring提供的接口操作有序集合
//        Set<ZSetOperations.TypedTuple> zset1 = new HashSet<ZSetOperations.TypedTuple>();
        Set<ZSetOperations.TypedTuple> zset2 = new HashSet<ZSetOperations.TypedTuple>();
//        int j = 9;
        for(int i=0;i<100;i++){
//            j--;
//            计算分数和值
//            Double score1 = Double.valueOf(i);
//            String value1 = "x"+i;
            Double score2 = Math.random();
            String value2 = "x"+i;

//            ZSetOperations.TypedTuple typedTuple1 = new DefaultTypedTuple(value1,score1);
//            zset1.add(typedTuple1);

            ZSetOperations.TypedTuple typedTuple2 = new DefaultTypedTuple(value2,score2);
            zset2.add(typedTuple2);
        }
//        redisTemplateService.zsetAdd("zset1",zset1);
        redisTemplateService.zsetAdd("zset2",zset2);


        Long size  = redisTemplateService.zsetTotal("zset2");
        System.out.println("集合的长度："+size);

//        计分数为score，下面的就是求0.5<=score<=0.6的元素
        System.out.println(redisTemplateService.zsetCount("zset2",3,6));
        Set<String> set = redisTemplateService.zsetRange("zset2",0,5);
        System.out.println("计分数为score，下面的就是求0.5<=score<=0.6的元素"+set);

//      截取集合内所有数据，并对集合按分数排序，并返回分数，每一个元素都是TypedTuple
        Set set5 =  redisTemplateService.zsetRangeWithScore("zset2");
        System.out.println("截取集合内所有数据，并对集合按分数排序，并返回分数，每一个元素都是TypedTuple");
         printTypedTuple(set5);

//     截取区间在0.3-0.8之间的数据，限制返回个数是5个，从第五个开始截取
        Set set6 = redisTemplate.opsForZSet().rangeByScoreWithScores("zset2",0.3,0.8,5,5);
        System.out.println("截取区间在0.3-0.8之间的数据，限制返回个数是5个，从第五个开始截取");
        printTypedTuple(set6);






    }

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Jmeter 测试插入中文数据乱码

1

压测

class="cursor-pointer"> 详细描述

class="cursor-pointer"> 错误截图