代码:

public class SpringDateRedisValue extends BaseSpringDateRedisTest {

    static final String STRING_KEY_ONE = "String:Key:One";
    static final String STRING_KEY_TWO = "String:Key:Two";
    static final String STRING_KEY_THREE = "String:Key:Three";
    static final String STRING_KEY_FOUR = "String:Key:Four";

  
    @Test
    public void testAdd() {
        getForValue().set( STRING_KEY_ONE, "12345678" );
        System.out.println( getForValue().get( STRING_KEY_ONE ) );
        getForValue().set( STRING_KEY_ONE,"h",0 );
        System.out.println( getForValue().get( STRING_KEY_ONE ) );
       // getForValue().setBit( STRING_KEY_ONE,2,true );
        final User user = new User( "小明同学", 23, 55.7D );
        getForValue().set( STRING_KEY_THREE,user );
        final User o = (User)getForValue().get( STRING_KEY_THREE );
        System.out.println(o);
    }

错误提示详情:

org.springframework.data.redis.serializer.SerializationException: Could not read JSON: Cannot construct instance of `com.example.springbootredis.entity.User` (no Creators, like default construct, exist): cannot deserialize from Object value (no delegate- or property-based Creator)
 at [Source: (byte[])"["com.example.springbootredis.entity.User",{"name":"小明同学","age":23,"weight":55.7}]"; line: 1, column: 45]; nested exception is com.fasterxml.jackson.databind.exc.InvalidDefinitionException: Cannot construct instance of `com.example.springbootredis.entity.User` (no Creators, like default construct, exist): cannot deserialize from Object value (no delegate- or property-based Creator)
 at [Source: (byte[])"["com.example.springbootredis.entity.User",{"name":"小明同学","age":23,"weight":55.7}]"; line: 1, column: 45]

	at org.springframework.data.redis.serializer.Jackson2JsonRedisSerializer.deserialize(Jackson2JsonRedisSerializer.java:75)
	at org.springframework.data.redis.core.AbstractOperations.deserializeValue(AbstractOperations.java:334)
	at org.springframework.data.redis.core.AbstractOperations$ValueDeserializingRedisCallback.doInRedis(AbstractOperations.java:60)
	at org.springframework.data.redis.core.RedisTemplate.execute(RedisTemplate.java:224)
	at org.springframework.data.redis.core.RedisTemplate.execute(RedisTemplate.java:184)
	at org.springframework.data.redis.core.AbstractOperations.execute(AbstractOperations.java:95)
	at org.springframework.data.redis.core.DefaultValueOperations.get(DefaultValueOperations.java:48)
	at com.example.springbootredis.redis.SpringDateRedisValue.testAdd(SpringDateRedisValue.java:37)
	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:497)
	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.RunBeforeTestExecutionCallbacks.evaluate(RunBeforeTestExecutionCallbacks.java:73)
	at org.springframework.test.context.junit4.statements.RunAfterTestExecutionCallbacks.evaluate(RunAfterTestExecutionCallbacks.java:83)
	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:251)
	at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.runChild(SpringJUnit4ClassRunner.java:97)
	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$2.evaluate(ParentRunner.java:268)
	at org.springframework.test.context.junit4.statements.RunBeforeTestClassCallbacks.evaluate(RunBeforeTestClassCallbacks.java:61)
	at org.springframework.test.context.junit4.statements.RunAfterTestClassCallbacks.evaluate(RunAfterTestClassCallbacks.java:70)
	at org.junit.runners.ParentRunner.run(ParentRunner.java:363)
	at org.springframework.test.context.junit4.SpringJUnit4ClassRunner.run(SpringJUnit4ClassRunner.java:190)
	at org.junit.runner.JUnitCore.run(JUnitCore.java:137)
	at com.intellij.junit4.JUnit4IdeaTestRunner.startRunnerWithArgs(JUnit4IdeaTestRunner.java:68)
	at com.intellij.rt.junit.IdeaTestRunner$Repeater.startRunnerWithArgs(IdeaTestRunner.java:33)
	at com.intellij.rt.junit.JUnitStarter.prepareStreamsAndStart(JUnitStarter.java:230)
	at com.intellij.rt.junit.JUnitStarter.main(JUnitStarter.java:58)
Caused by: com.fasterxml.jackson.databind.exc.InvalidDefinitionException: Cannot construct instance of `com.example.springbootredis.entity.User` (no Creators, like default construct, exist): cannot deserialize from Object value (no delegate- or property-based Creator)
 at [Source: (byte[])"["com.example.springbootredis.entity.User",{"name":"小明同学","age":23,"weight":55.7}]"; line: 1, column: 45]
	at com.fasterxml.jackson.databind.exc.InvalidDefinitionException.from(InvalidDefinitionException.java:67)
	at com.fasterxml.jackson.databind.DeserializationContext.reportBadDefinition(DeserializationContext.java:1451)
	at com.fasterxml.jackson.databind.DeserializationContext.handleMissingInstantiator(DeserializationContext.java:1027)
	at com.fasterxml.jackson.databind.deser.BeanDeserializerBase.deserializeFromObjectUsingNonDefault(BeanDeserializerBase.java:1297)
	at com.fasterxml.jackson.databind.deser.BeanDeserializer.deserializeFromObject(BeanDeserializer.java:326)
	at com.fasterxml.jackson.databind.deser.BeanDeserializer.deserialize(BeanDeserializer.java:159)
	at com.fasterxml.jackson.databind.jsontype.impl.AsArrayTypeDeserializer._deserialize(AsArrayTypeDeserializer.java:116)
	at com.fasterxml.jackson.databind.jsontype.impl.AsArrayTypeDeserializer.deserializeTypedFromAny(AsArrayTypeDeserializer.java:71)
	at com.fasterxml.jackson.databind.deser.std.UntypedObjectDeserializer$Vanilla.deserializeWithType(UntypedObjectDeserializer.java:712)
	at com.fasterxml.jackson.databind.deser.impl.TypeWrappedDeserializer.deserialize(TypeWrappedDeserializer.java:68)
	at com.fasterxml.jackson.databind.ObjectMapper._readMapAndClose(ObjectMapper.java:4013)
	at com.fasterxml.jackson.databind.ObjectMapper.readValue(ObjectMapper.java:3129)
	at org.springframework.data.redis.serializer.Jackson2JsonRedisSerializer.deserialize(Jackson2JsonRedisSerializer.java:73)
	... 37 more

看了一下错误提示.提示序列化问题,无法正常解析json数据去构造一个对象;

通过可视化工具Redis Desktop Manager 查看对应的key数据

这特么的不是一个正确的json

查看redisconfig配置:

看了一眼, 当时这段配置是复制粘贴过来的;对于 redis String数据类型的存储是不适合用jackson 序列化的还是乖乖使用JDK序列化,至于为什么不使用String序列化, 是因为如果你想要往String类型里面存对象, 对象序列化成字符串肯定会报错;肯定提示类不能转成字符串;

当我把序列化方式改成JDK之后就不报错了; 只不过通过可视化去看数据的时候就会发现你看不懂了;完全不知道存储的是什么;

测试结果:

 

但是其实不推荐大家向String存储对象,更加推荐大家想hash存储对象;
value 的序列化方式也最好采用String序列化;不推荐使用JDK 序列化,毕竟偶尔想查看一下value的值 总不能每次写个测试或者API去调用吧; 还是需要借助可视化工具;