springboot缓存之整合redis

 

一\引入redis

pom.xml中添加

<dependency>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-data-redis</artifactId>
</dependency>

二\application.properties中写入

spring.redis.host=192.168.3.18 #redis地址(虚拟机)

打开RedisAutoConfiguration可以看到

@ConditionalOnClass({RedisOperations.class})
@EnableConfigurationProperties({RedisProperties.class})
@Import({LettuceConnectionConfiguration.class, JedisConnectionConfiguration.class})
public class RedisAutoConfiguration {
    public RedisAutoConfiguration() {
    }

    @Bean
    @ConditionalOnMissingBean(
        name = {"redisTemplate"}
    )
    public RedisTemplate<Object, Object> redisTemplate(RedisConnectionFactory redisConnectionFactory) throws UnknownHostException {
        RedisTemplate<Object, Object> template = new RedisTemplate();
        template.setConnectionFactory(redisConnectionFactory);
        return template;
    }

    @Bean
    @ConditionalOnMissingBean
    public StringRedisTemplate stringRedisTemplate(RedisConnectionFactory redisConnectionFactory) throws UnknownHostException {
        StringRedisTemplate template = new StringRedisTemplate();
        template.setConnectionFactory(redisConnectionFactory);
        return template;
    }
}

三\运行redis

四\使用测试类进行测试

package com.example.springdatacache;

import com.example.springdatacache.bean.Employee;
import com.example.springdatacache.mapper.EmployeeMapper;
import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.data.redis.core.StringRedisTemplate;

@SpringBootTest
class SpringdataCacheApplicationTests {

    @Autowired
    EmployeeMapper employeeMapper;

    @Autowired
    StringRedisTemplate stringRedisTemplate;   //操作k-v都是字符串的

    @Autowired
    RedisTemplate redisTemplate;      //k-v都是对象的

    /**
     * Redis常见的五大数据类型
     * String(字符串)  ,List(列表)   ,Set(集合)    ,Hash(散列)    ,ZSet(有序集合)
     * stringRedisTemplate.opsForValue() 缓存String(字符串)
     * stringRedisTemplate.opsForList()  缓存List(列表)
     * stringRedisTemplate.opsForSet()  缓存Set(集合)
     * stringRedisTemplate.opsForHash()  缓存Hash(散列)
     * stringRedisTemplate.opsForZSet()  缓存ZSet(有序集合)
     */
    @Test
    public void test01(){
        //给redis中保存数据
        stringRedisTemplate.opsForValue().append("msg","1999999");
    }

    //测试保存对象
    @Test
    public void test02(){
        Employee empById = employeeMapper.getEmpById(1);
        redisTemplate.opsForValue().set("emp-01",empById);
    }

    @Test
    void contextLoads() {
        Employee empById = employeeMapper.getEmpById(1);
        System.out.println(empById);
    }

}

 

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.example.springdatacache.bean.Employee]

  at org.springframework.data.redis.serializer.JdkSerializationRedisSerializer.serialize(JdkSerializationRedisSerializer.java:96)
  at org.springframework.data.redis.core.AbstractOperations.rawValue(AbstractOperations.java:127)
  at org.springframework.data.redis.core.DefaultValueOperations.set(DefaultValueOperations.java:235)
  at com.example.springdatacache.SpringdataCacheApplicationTests.test02(SpringdataCacheApplicationTests.java:42)
  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.platform.commons.util.ReflectionUtils.invokeMethod(ReflectionUtils.java:675)
  at org.junit.jupiter.engine.execution.MethodInvocation.proceed(MethodInvocation.java:60)
  at org.junit.jupiter.engine.execution.InvocationInterceptorChain$ValidatingInvocation.proceed(InvocationInterceptorChain.java:125)
  at org.junit.jupiter.engine.extension.TimeoutExtension.intercept(TimeoutExtension.java:132)
  at org.junit.jupiter.engine.extension.TimeoutExtension.interceptTestableMethod(TimeoutExtension.java:124)
  at org.junit.jupiter.engine.extension.TimeoutExtension.interceptTestMethod(TimeoutExtension.java:74)
  at org.junit.jupiter.engine.execution.ExecutableInvoker$ReflectiveInterceptorCall.lambda$ofVoidMethod$0(ExecutableInvoker.java:115)
  at org.junit.jupiter.engine.execution.ExecutableInvoker.lambda$invoke$0(ExecutableInvoker.java:105)
  at org.junit.jupiter.engine.execution.InvocationInterceptorChain$InterceptedInvocation.proceed(InvocationInterceptorChain.java:104)
  at org.junit.jupiter.engine.execution.InvocationInterceptorChain.proceed(InvocationInterceptorChain.java:62)
  at org.junit.jupiter.engine.execution.InvocationInterceptorChain.chainAndInvoke(InvocationInterceptorChain.java:43)
  at org.junit.jupiter.engine.execution.InvocationInterceptorChain.invoke(InvocationInterceptorChain.java:35)
  at org.junit.jupiter.engine.execution.ExecutableInvoker.invoke(ExecutableInvoker.java:104)
  at org.junit.jupiter.engine.execution.ExecutableInvoker.invoke(ExecutableInvoker.java:98)
  at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.lambda$invokeTestMethod$6(TestMethodTestDescriptor.java:202)
  at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
  at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.invokeTestMethod(TestMethodTestDescriptor.java:198)
  at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.execute(TestMethodTestDescriptor.java:135)
  at org.junit.jupiter.engine.descriptor.TestMethodTestDescriptor.execute(TestMethodTestDescriptor.java:69)
  at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$5(NodeTestTask.java:135)
  at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
  at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$7(NodeTestTask.java:125)
  at org.junit.platform.engine.support.hierarchical.Node.around(Node.java:135)
  at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$8(NodeTestTask.java:123)
  at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
  at org.junit.platform.engine.support.hierarchical.NodeTestTask.executeRecursively(NodeTestTask.java:122)
  at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:80)
  at java.util.ArrayList.forEach(ArrayList.java:1257)
  at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.invokeAll(SameThreadHierarchicalTestExecutorService.java:38)
  at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$5(NodeTestTask.java:139)
  at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
  at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$7(NodeTestTask.java:125)
  at org.junit.platform.engine.support.hierarchical.Node.around(Node.java:135)
  at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$8(NodeTestTask.java:123)
  at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
  at org.junit.platform.engine.support.hierarchical.NodeTestTask.executeRecursively(NodeTestTask.java:122)
  at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:80)
  at java.util.ArrayList.forEach(ArrayList.java:1257)
  at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.invokeAll(SameThreadHierarchicalTestExecutorService.java:38)
  at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$5(NodeTestTask.java:139)
  at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
  at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$7(NodeTestTask.java:125)
  at org.junit.platform.engine.support.hierarchical.Node.around(Node.java:135)
  at org.junit.platform.engine.support.hierarchical.NodeTestTask.lambda$executeRecursively$8(NodeTestTask.java:123)
  at org.junit.platform.engine.support.hierarchical.ThrowableCollector.execute(ThrowableCollector.java:73)
  at org.junit.platform.engine.support.hierarchical.NodeTestTask.executeRecursively(NodeTestTask.java:122)
  at org.junit.platform.engine.support.hierarchical.NodeTestTask.execute(NodeTestTask.java:80)
  at org.junit.platform.engine.support.hierarchical.SameThreadHierarchicalTestExecutorService.submit(SameThreadHierarchicalTestExecutorService.java:32)
  at org.junit.platform.engine.support.hierarchical.HierarchicalTestExecutor.execute(HierarchicalTestExecutor.java:57)
  at org.junit.platform.engine.support.hierarchical.HierarchicalTestEngine.execute(HierarchicalTestEngine.java:51)
  at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:229)
  at org.junit.platform.launcher.core.DefaultLauncher.lambda$execute$6(DefaultLauncher.java:197)
  at org.junit.platform.launcher.core.DefaultLauncher.withInterceptedStreams(DefaultLauncher.java:211)
  at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:191)
  at org.junit.platform.launcher.core.DefaultLauncher.execute(DefaultLauncher.java:128)
  at com.intellij.junit5.JUnit5IdeaTestRunner.startRunnerWithArgs(JUnit5IdeaTestRunner.java:69)
  at com.intellij.rt.execution.junit.IdeaTestRunner$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.example.springdatacache.bean.Employee]
  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:94)
  ... 66 more
Caused by: java.lang.IllegalArgumentException: DefaultSerializer requires a Serializable payload but received an object of type [com.example.springdatacache.bean.Employee]
  at org.springframework.core.serializer.DefaultSerializer.serialize(DefaultSerializer.java:43)
  at org.springframework.core.serializer.support.SerializingConverter.convert(SerializingConverter.java:63)
  ... 68 more

修改javabean  Employee类:

import java.io.Serializable;

public class Employee implements Serializable {

此时依然出现问题:

默认如果保存对象,使用jdk序列化机制,序列化后的数据保存到redis中 解决方法: 1-将数据以json的方式保存 (1)自己将对象转为json (2)redisTemplate默认的序列化规则,改变默认的序列化规则

进入RedisTemplate类,发现一系列序列化器

进入RedisSerializer类

ctrl+H

五\新建config包MyRedisConfig类

进入RedisAutoConfiguration类中复制

@Bean
    @ConditionalOnMissingBean(
        name = {"redisTemplate"}
    )
    public RedisTemplate<Object, Object> redisTemplate(RedisConnectionFactory redisConnectionFactory) throws UnknownHostException {
        RedisTemplate<Object, Object> template = new RedisTemplate();
        template.setConnectionFactory(redisConnectionFactory);
        return template;
    }

编写: 

package com.example.springdatacache.config;

import com.example.springdatacache.bean.Employee;
import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.data.redis.connection.RedisConnectionFactory;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.data.redis.serializer.Jackson2JsonRedisSerializer;

import java.net.UnknownHostException;

@Configuration
public class MyRedisConfig {
    @Bean
    public RedisTemplate<Object, Employee> empRedisTemplate(RedisConnectionFactory redisConnectionFactory) throws UnknownHostException {
        RedisTemplate<Object, Employee> template = new RedisTemplate();
        template.setConnectionFactory(redisConnectionFactory);
        Jackson2JsonRedisSerializer<Employee> employeeJackson2JsonRedisSerializer = new Jackson2JsonRedisSerializer<Employee>(Employee.class);
        template.setDefaultSerializer(employeeJackson2JsonRedisSerializer);
        return template;
    }
}

六\修改测试类

           新增

@Autowired
    RedisTemplate<Object,Employee> empRedisTemplate;

           修改

//测试保存对象
    @Test
    public void test02(){
        Employee empById = employeeMapper.getEmpById(1);
        empRedisTemplate.opsForValue().set("emp-01",empById);
    }