mybatis xml的字符串表达式中不要包含in（因为in是关键字，除此之外，还有很多关键字都不要放在这里）！！！
假如你要使用if语句判断Query类的成员变量in是否为null，你可能会这么写： <if test="null != query.in"></if>（错误）
正确的做法是把Query类的in变量名改成其它名字，比如改成contains <if test="null != query.contains"></if>（正确）
分类 开发篇 下的文章
Spring Cloud Alibaba 2021.0.1.0 踩坑记录
我打算把Spring Cloud Alibaba升级个版本，看看有什么新特性，结果升级后死活启动不了。
事情是这样的，跟往常一样，我先去Spring官网找到Spring Cloud Alibaba的最新的版本号，如下图所示：
可以看到最新的版本是2021.0.1.0
我默默记下这个版本号...
然后点了右上角的那只章鱼猫
在Wiki里找到版本说明，如下图所示：
现在我知道了Spring Cloud Alibaba Version、Spring Cloud Version和Spring Boot Version三者版本对应关系了！
我再次回到Spring官网，然后打开Spring Cloud Alibaba的Reference，根据文档，一顿操作。
其实大概就只有三步：
- 添加依赖
<!--在父工程添加以下依赖-->
<properties>
<spring.cloud.version>2021.0.1</spring.cloud.version>
<spring-boot-dependencies.version>2.6.3</spring-boot-dependencies.version>
<com.alibaba.cloud.spring-cloud-alibaba-dependencies.version>2021.0.1.0
</com.alibaba.cloud.spring-cloud-alibaba-dependencies.version>
</properties>
<dependencyManagement>
<dependencies>
<!--官网里使用spring-boot-starter-parent作为父工程而没有导入这条依赖，实际作用相同-->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-dependencies</artifactId>
<version>${spring-boot-dependencies.version}</version>
</dependency>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-dependencies</artifactId>
<version>${spring.cloud.version}</version>
<type>pom</type>
<scope>import</scope>
</dependency>
<dependency>
<groupId>com.alibaba.cloud</groupId>
<artifactId>spring-cloud-alibaba-dependencies</artifactId>
<version>${com.alibaba.cloud.spring-cloud-alibaba-dependencies.version}</version>
<type>pom</type>
<scope>import</scope>
</dependency>
</dependencies>
</dependencyManagement><!--在module中添加以下依赖-->
<dependency>
<groupId>com.alibaba.cloud</groupId>
<artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
</dependency>- 配置yaml
spring:
cloud:
nacos:
discovery:
server-addr: 127.0.0.1:8848- 在主类上添加@EnableDiscoveryClient注解
激动的心，颤抖的手，点击运行！（提前启动好了Nacos）
2022-09-05 00:04:32.047 INFO 37828 --- [ restartedMain] o.apache.catalina.core.StandardService : Starting service [Tomcat]
2022-09-05 00:04:32.047 INFO 37828 --- [ restartedMain] org.apache.catalina.core.StandardEngine : Starting Servlet engine: [Apache Tomcat/9.0.56]
2022-09-05 00:04:32.109 INFO 37828 --- [ restartedMain] o.a.c.c.C.[Tomcat].[localhost].[/] : Initializing Spring embedded WebApplicationContext
2022-09-05 00:04:32.109 INFO 37828 --- [ restartedMain] w.s.c.ServletWebServerApplicationContext : Root WebApplicationContext: initialization completed in 1320 ms
2022-09-05 00:04:32.504 WARN 37828 --- [ restartedMain] ConfigServletWebServerApplicationContext : Exception encountered during context initialization - cancelling refresh attempt: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'requestMappingHandlerAdapter' defined in class path resource [org/springframework/boot/autoconfigure/web/servlet/WebMvcAutoConfiguration$EnableWebMvcConfiguration.class]: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter]: Factory method 'requestMappingHandlerAdapter' threw exception; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'messageConverters' defined in class path resource [org/springframework/boot/autoconfigure/http/HttpMessageConvertersAutoConfiguration.class]: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.springframework.boot.autoconfigure.http.HttpMessageConverters]: Factory method 'messageConverters' threw exception; nested exception is org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'mappingJackson2HttpMessageConverter' defined in class path resource [org/springframework/boot/autoconfigure/http/JacksonHttpMessageConvertersConfiguration$MappingJackson2HttpMessageConverterConfiguration.class]: Unsatisfied dependency expressed through method 'mappingJackson2HttpMessageConverter' parameter 0; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'jacksonObjectMapper' defined in class path resource [org/springframework/boot/autoconfigure/jackson/JacksonAutoConfiguration$JacksonObjectMapperConfiguration.class]: Post-processing of merged bean definition failed; nested exception is java.lang.IllegalStateException: Failed to introspect Class [com.fasterxml.jackson.databind.ObjectMapper] from ClassLoader [jdk.internal.loader.ClassLoaders$AppClassLoader@2437c6dc]
2022-09-05 00:04:32.507 INFO 37828 --- [ restartedMain] o.apache.catalina.core.StandardService : Stopping service [Tomcat]
2022-09-05 00:04:32.523 INFO 37828 --- [ restartedMain] ConditionEvaluationReportLoggingListener :
Error starting ApplicationContext. To display the conditions report re-run your application with 'debug' enabled.
2022-09-05 00:04:32.551 ERROR 37828 --- [ restartedMain] o.s.boot.SpringApplication : Application run failed
org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'requestMappingHandlerAdapter' defined in class path resource [org/springframework/boot/autoconfigure/web/servlet/WebMvcAutoConfiguration$EnableWebMvcConfiguration.class]: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter]: Factory method 'requestMappingHandlerAdapter' threw exception; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'messageConverters' defined in class path resource [org/springframework/boot/autoconfigure/http/HttpMessageConvertersAutoConfiguration.class]: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.springframework.boot.autoconfigure.http.HttpMessageConverters]: Factory method 'messageConverters' threw exception; nested exception is org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'mappingJackson2HttpMessageConverter' defined in class path resource [org/springframework/boot/autoconfigure/http/JacksonHttpMessageConvertersConfiguration$MappingJackson2HttpMessageConverterConfiguration.class]: Unsatisfied dependency expressed through method 'mappingJackson2HttpMessageConverter' parameter 0; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'jacksonObjectMapper' defined in class path resource [org/springframework/boot/autoconfigure/jackson/JacksonAutoConfiguration$JacksonObjectMapperConfiguration.class]: Post-processing of merged bean definition failed; nested exception is java.lang.IllegalStateException: Failed to introspect Class [com.fasterxml.jackson.databind.ObjectMapper] from ClassLoader [jdk.internal.loader.ClassLoaders$AppClassLoader@2437c6dc]
at org.springframework.beans.factory.support.ConstructorResolver.instantiate(ConstructorResolver.java:658) ~[spring-beans-5.3.15.jar:5.3.15]
at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:638) ~[spring-beans-5.3.15.jar:5.3.15]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateUsingFactoryMethod(AbstractAutowireCapableBeanFactory.java:1352) ~[spring-beans-5.3.15.jar:5.3.15]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1195) ~[spring-beans-5.3.15.jar:5.3.15]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:582) ~[spring-beans-5.3.15.jar:5.3.15]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:542) ~[spring-beans-5.3.15.jar:5.3.15]
at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:335) ~[spring-beans-5.3.15.jar:5.3.15]
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:234) ~[spring-beans-5.3.15.jar:5.3.15]
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:333) ~[spring-beans-5.3.15.jar:5.3.15]
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:208) ~[spring-beans-5.3.15.jar:5.3.15]
at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:953) ~[spring-beans-5.3.15.jar:5.3.15]
at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:918) ~[spring-context-5.3.15.jar:5.3.15]
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:583) ~[spring-context-5.3.15.jar:5.3.15]
at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:145) ~[spring-boot-2.6.3.jar:2.6.3]
at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:732) ~[spring-boot-2.6.3.jar:2.6.3]
at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:414) ~[spring-boot-2.6.3.jar:2.6.3]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:302) ~[spring-boot-2.6.3.jar:2.6.3]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1303) ~[spring-boot-2.6.3.jar:2.6.3]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1292) ~[spring-boot-2.6.3.jar:2.6.3]
at cn.imcaoxuan.FileManagerApplication.main(FileManagerApplication.java:11) ~[classes/:na]
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:na]
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:na]
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:na]
at java.base/java.lang.reflect.Method.invoke(Method.java:566) ~[na:na]
at org.springframework.boot.devtools.restart.RestartLauncher.run(RestartLauncher.java:49) ~[spring-boot-devtools-2.6.3.jar:2.6.3]
Caused by: org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter]: Factory method 'requestMappingHandlerAdapter' threw exception; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'messageConverters' defined in class path resource [org/springframework/boot/autoconfigure/http/HttpMessageConvertersAutoConfiguration.class]: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.springframework.boot.autoconfigure.http.HttpMessageConverters]: Factory method 'messageConverters' threw exception; nested exception is org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'mappingJackson2HttpMessageConverter' defined in class path resource [org/springframework/boot/autoconfigure/http/JacksonHttpMessageConvertersConfiguration$MappingJackson2HttpMessageConverterConfiguration.class]: Unsatisfied dependency expressed through method 'mappingJackson2HttpMessageConverter' parameter 0; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'jacksonObjectMapper' defined in class path resource [org/springframework/boot/autoconfigure/jackson/JacksonAutoConfiguration$JacksonObjectMapperConfiguration.class]: Post-processing of merged bean definition failed; nested exception is java.lang.IllegalStateException: Failed to introspect Class [com.fasterxml.jackson.databind.ObjectMapper] from ClassLoader [jdk.internal.loader.ClassLoaders$AppClassLoader@2437c6dc]
at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:185) ~[spring-beans-5.3.15.jar:5.3.15]
at org.springframework.beans.factory.support.ConstructorResolver.instantiate(ConstructorResolver.java:653) ~[spring-beans-5.3.15.jar:5.3.15]
... 24 common frames omitted
Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'messageConverters' defined in class path resource [org/springframework/boot/autoconfigure/http/HttpMessageConvertersAutoConfiguration.class]: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.springframework.boot.autoconfigure.http.HttpMessageConverters]: Factory method 'messageConverters' threw exception; nested exception is org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'mappingJackson2HttpMessageConverter' defined in class path resource [org/springframework/boot/autoconfigure/http/JacksonHttpMessageConvertersConfiguration$MappingJackson2HttpMessageConverterConfiguration.class]: Unsatisfied dependency expressed through method 'mappingJackson2HttpMessageConverter' parameter 0; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'jacksonObjectMapper' defined in class path resource [org/springframework/boot/autoconfigure/jackson/JacksonAutoConfiguration$JacksonObjectMapperConfiguration.class]: Post-processing of merged bean definition failed; nested exception is java.lang.IllegalStateException: Failed to introspect Class [com.fasterxml.jackson.databind.ObjectMapper] from ClassLoader [jdk.internal.loader.ClassLoaders$AppClassLoader@2437c6dc]
at org.springframework.beans.factory.support.ConstructorResolver.instantiate(ConstructorResolver.java:658) ~[spring-beans-5.3.15.jar:5.3.15]
at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:638) ~[spring-beans-5.3.15.jar:5.3.15]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateUsingFactoryMethod(AbstractAutowireCapableBeanFactory.java:1352) ~[spring-beans-5.3.15.jar:5.3.15]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1195) ~[spring-beans-5.3.15.jar:5.3.15]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:582) ~[spring-beans-5.3.15.jar:5.3.15]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:542) ~[spring-beans-5.3.15.jar:5.3.15]
at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:335) ~[spring-beans-5.3.15.jar:5.3.15]
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:234) ~[spring-beans-5.3.15.jar:5.3.15]
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:333) ~[spring-beans-5.3.15.jar:5.3.15]
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:208) ~[spring-beans-5.3.15.jar:5.3.15]
at org.springframework.beans.factory.config.DependencyDescriptor.resolveCandidate(DependencyDescriptor.java:276) ~[spring-beans-5.3.15.jar:5.3.15]
at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1389) ~[spring-beans-5.3.15.jar:5.3.15]
at org.springframework.beans.factory.support.DefaultListableBeanFactory$DependencyObjectProvider.getIfAvailable(DefaultListableBeanFactory.java:2030) ~[spring-beans-5.3.15.jar:5.3.15]
at org.springframework.beans.factory.support.DefaultListableBeanFactory$DependencyObjectProvider.ifAvailable(DefaultListableBeanFactory.java:2041) ~[spring-beans-5.3.15.jar:5.3.15]
at org.springframework.boot.autoconfigure.web.servlet.WebMvcAutoConfiguration$WebMvcAutoConfigurationAdapter.configureMessageConverters(WebMvcAutoConfiguration.java:232) ~[spring-boot-autoconfigure-2.6.3.jar:2.6.3]
at org.springframework.web.servlet.config.annotation.WebMvcConfigurerComposite.configureMessageConverters(WebMvcConfigurerComposite.java:137) ~[spring-webmvc-5.3.15.jar:5.3.15]
at org.springframework.web.servlet.config.annotation.DelegatingWebMvcConfiguration.configureMessageConverters(DelegatingWebMvcConfiguration.java:118) ~[spring-webmvc-5.3.15.jar:5.3.15]
at org.springframework.web.servlet.config.annotation.WebMvcConfigurationSupport.getMessageConverters(WebMvcConfigurationSupport.java:865) ~[spring-webmvc-5.3.15.jar:5.3.15]
at org.springframework.web.servlet.config.annotation.WebMvcConfigurationSupport.requestMappingHandlerAdapter(WebMvcConfigurationSupport.java:673) ~[spring-webmvc-5.3.15.jar:5.3.15]
at org.springframework.boot.autoconfigure.web.servlet.WebMvcAutoConfiguration$EnableWebMvcConfiguration.requestMappingHandlerAdapter(WebMvcAutoConfiguration.java:419) ~[spring-boot-autoconfigure-2.6.3.jar:2.6.3]
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:na]
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:na]
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:na]
at java.base/java.lang.reflect.Method.invoke(Method.java:566) ~[na:na]
at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:154) ~[spring-beans-5.3.15.jar:5.3.15]
... 25 common frames omitted
Caused by: org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.springframework.boot.autoconfigure.http.HttpMessageConverters]: Factory method 'messageConverters' threw exception; nested exception is org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'mappingJackson2HttpMessageConverter' defined in class path resource [org/springframework/boot/autoconfigure/http/JacksonHttpMessageConvertersConfiguration$MappingJackson2HttpMessageConverterConfiguration.class]: Unsatisfied dependency expressed through method 'mappingJackson2HttpMessageConverter' parameter 0; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'jacksonObjectMapper' defined in class path resource [org/springframework/boot/autoconfigure/jackson/JacksonAutoConfiguration$JacksonObjectMapperConfiguration.class]: Post-processing of merged bean definition failed; nested exception is java.lang.IllegalStateException: Failed to introspect Class [com.fasterxml.jackson.databind.ObjectMapper] from ClassLoader [jdk.internal.loader.ClassLoaders$AppClassLoader@2437c6dc]
at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:185) ~[spring-beans-5.3.15.jar:5.3.15]
at org.springframework.beans.factory.support.ConstructorResolver.instantiate(ConstructorResolver.java:653) ~[spring-beans-5.3.15.jar:5.3.15]
... 49 common frames omitted
Caused by: org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'mappingJackson2HttpMessageConverter' defined in class path resource [org/springframework/boot/autoconfigure/http/JacksonHttpMessageConvertersConfiguration$MappingJackson2HttpMessageConverterConfiguration.class]: Unsatisfied dependency expressed through method 'mappingJackson2HttpMessageConverter' parameter 0; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'jacksonObjectMapper' defined in class path resource [org/springframework/boot/autoconfigure/jackson/JacksonAutoConfiguration$JacksonObjectMapperConfiguration.class]: Post-processing of merged bean definition failed; nested exception is java.lang.IllegalStateException: Failed to introspect Class [com.fasterxml.jackson.databind.ObjectMapper] from ClassLoader [jdk.internal.loader.ClassLoaders$AppClassLoader@2437c6dc]
at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:800) ~[spring-beans-5.3.15.jar:5.3.15]
at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:541) ~[spring-beans-5.3.15.jar:5.3.15]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateUsingFactoryMethod(AbstractAutowireCapableBeanFactory.java:1352) ~[spring-beans-5.3.15.jar:5.3.15]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1195) ~[spring-beans-5.3.15.jar:5.3.15]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:582) ~[spring-beans-5.3.15.jar:5.3.15]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:542) ~[spring-beans-5.3.15.jar:5.3.15]
at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:335) ~[spring-beans-5.3.15.jar:5.3.15]
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:234) ~[spring-beans-5.3.15.jar:5.3.15]
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:333) ~[spring-beans-5.3.15.jar:5.3.15]
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:208) ~[spring-beans-5.3.15.jar:5.3.15]
at org.springframework.beans.factory.config.DependencyDescriptor.resolveCandidate(DependencyDescriptor.java:276) ~[spring-beans-5.3.15.jar:5.3.15]
at org.springframework.beans.factory.support.DefaultListableBeanFactory.addCandidateEntry(DefaultListableBeanFactory.java:1614) ~[spring-beans-5.3.15.jar:5.3.15]
at org.springframework.beans.factory.support.DefaultListableBeanFactory.findAutowireCandidates(DefaultListableBeanFactory.java:1571) ~[spring-beans-5.3.15.jar:5.3.15]
at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveMultipleBeans(DefaultListableBeanFactory.java:1415) ~[spring-beans-5.3.15.jar:5.3.15]
at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1347) ~[spring-beans-5.3.15.jar:5.3.15]
at org.springframework.beans.factory.support.DefaultListableBeanFactory$DependencyObjectProvider.resolveStream(DefaultListableBeanFactory.java:2117) ~[spring-beans-5.3.15.jar:5.3.15]
at org.springframework.beans.factory.support.DefaultListableBeanFactory$DependencyObjectProvider.orderedStream(DefaultListableBeanFactory.java:2111) ~[spring-beans-5.3.15.jar:5.3.15]
at org.springframework.boot.autoconfigure.http.HttpMessageConvertersAutoConfiguration.messageConverters(HttpMessageConvertersAutoConfiguration.java:70) ~[spring-boot-autoconfigure-2.6.3.jar:2.6.3]
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:na]
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:na]
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:na]
at java.base/java.lang.reflect.Method.invoke(Method.java:566) ~[na:na]
at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:154) ~[spring-beans-5.3.15.jar:5.3.15]
... 50 common frames omitted
Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'jacksonObjectMapper' defined in class path resource [org/springframework/boot/autoconfigure/jackson/JacksonAutoConfiguration$JacksonObjectMapperConfiguration.class]: Post-processing of merged bean definition failed; nested exception is java.lang.IllegalStateException: Failed to introspect Class [com.fasterxml.jackson.databind.ObjectMapper] from ClassLoader [jdk.internal.loader.ClassLoaders$AppClassLoader@2437c6dc]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:597) ~[spring-beans-5.3.15.jar:5.3.15]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:542) ~[spring-beans-5.3.15.jar:5.3.15]
at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:335) ~[spring-beans-5.3.15.jar:5.3.15]
at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:234) ~[spring-beans-5.3.15.jar:5.3.15]
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:333) ~[spring-beans-5.3.15.jar:5.3.15]
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:208) ~[spring-beans-5.3.15.jar:5.3.15]
at org.springframework.beans.factory.config.DependencyDescriptor.resolveCandidate(DependencyDescriptor.java:276) ~[spring-beans-5.3.15.jar:5.3.15]
at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1389) ~[spring-beans-5.3.15.jar:5.3.15]
at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1309) ~[spring-beans-5.3.15.jar:5.3.15]
at org.springframework.beans.factory.support.ConstructorResolver.resolveAutowiredArgument(ConstructorResolver.java:887) ~[spring-beans-5.3.15.jar:5.3.15]
at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:791) ~[spring-beans-5.3.15.jar:5.3.15]
... 72 common frames omitted
Caused by: java.lang.IllegalStateException: Failed to introspect Class [com.fasterxml.jackson.databind.ObjectMapper] from ClassLoader [jdk.internal.loader.ClassLoaders$AppClassLoader@2437c6dc]
at org.springframework.util.ReflectionUtils.getDeclaredMethods(ReflectionUtils.java:481) ~[spring-core-5.3.15.jar:5.3.15]
at org.springframework.util.ReflectionUtils.doWithLocalMethods(ReflectionUtils.java:321) ~[spring-core-5.3.15.jar:5.3.15]
at org.springframework.beans.factory.annotation.InitDestroyAnnotationBeanPostProcessor.buildLifecycleMetadata(InitDestroyAnnotationBeanPostProcessor.java:232) ~[spring-beans-5.3.15.jar:5.3.15]
at org.springframework.beans.factory.annotation.InitDestroyAnnotationBeanPostProcessor.findLifecycleMetadata(InitDestroyAnnotationBeanPostProcessor.java:210) ~[spring-beans-5.3.15.jar:5.3.15]
at org.springframework.beans.factory.annotation.InitDestroyAnnotationBeanPostProcessor.postProcessMergedBeanDefinition(InitDestroyAnnotationBeanPostProcessor.java:149) ~[spring-beans-5.3.15.jar:5.3.15]
at org.springframework.context.annotation.CommonAnnotationBeanPostProcessor.postProcessMergedBeanDefinition(CommonAnnotationBeanPostProcessor.java:305) ~[spring-context-5.3.15.jar:5.3.15]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.applyMergedBeanDefinitionPostProcessors(AbstractAutowireCapableBeanFactory.java:1116) ~[spring-beans-5.3.15.jar:5.3.15]
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:594) ~[spring-beans-5.3.15.jar:5.3.15]
... 82 common frames omitted
Caused by: java.lang.NoClassDefFoundError: com/fasterxml/jackson/core/exc/StreamWriteException
at java.base/java.lang.Class.getDeclaredMethods0(Native Method) ~[na:na]
at java.base/java.lang.Class.privateGetDeclaredMethods(Class.java:3167) ~[na:na]
at java.base/java.lang.Class.getDeclaredMethods(Class.java:2310) ~[na:na]
at org.springframework.util.ReflectionUtils.getDeclaredMethods(ReflectionUtils.java:463) ~[spring-core-5.3.15.jar:5.3.15]
... 89 common frames omitted
Caused by: java.lang.ClassNotFoundException: com.fasterxml.jackson.core.exc.StreamWriteException
at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:582) ~[na:na]
at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:178) ~[na:na]
at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:521) ~[na:na]
... 93 common frames omitted
Disconnected from the target VM, address: '127.0.0.1:59002', transport: 'socket'
Process finished with exit code 0
报错提示ClassNotFoundException，很明显，这种问题一般都是出现在缺少依赖的情况下的，但是jackson这个东西，我之前一直用的好好的啊！怎么突然就说找不到了呢？
我在密密麻麻的POM文件中看了半天，也没发现什么问题。我也没做多大改动啊，怎么就跑不起来了呢？
我想了下，问题会不会是依赖冲突导致的？
我去看看External Libraries：
卧槽，怎么会有两个jackson-core?版本还不一致！
终于找到原因了！
接下来，我修改了nacos的依赖：
<dependency>
<groupId>com.alibaba.cloud</groupId>
<artifactId>spring-cloud-starter-alibaba-nacos-discovery</artifactId>
<!--排除此依赖对jackson-core的依赖-->
<exclusions>
<exclusion>
<groupId>com.fasterxml.jackson.core</groupId>
<artifactId>jackson-core</artifactId>
</exclusion>
</exclusions>
</dependency>改完后External Libraries里就只剩下一个jackson-core-2.13.1了
刷新一下Maven，再次运行，终于Run起来了！
2022-09-05 00:26:59.919 INFO 20320 --- [ restartedMain] o.apache.catalina.core.StandardService : Starting service [Tomcat]
2022-09-05 00:26:59.919 INFO 20320 --- [ restartedMain] org.apache.catalina.core.StandardEngine : Starting Servlet engine: [Apache Tomcat/9.0.56]
2022-09-05 00:26:59.980 INFO 20320 --- [ restartedMain] o.a.c.c.C.[Tomcat].[localhost].[/] : Initializing Spring embedded WebApplicationContext
2022-09-05 00:26:59.981 INFO 20320 --- [ restartedMain] w.s.c.ServletWebServerApplicationContext : Root WebApplicationContext: initialization completed in 1282 ms
2022-09-05 00:27:01.624 INFO 20320 --- [ restartedMain] o.s.cloud.commons.util.InetUtils : Cannot determine local hostname
2022-09-05 00:27:01.911 INFO 20320 --- [ restartedMain] o.s.b.d.a.OptionalLiveReloadServer : LiveReload server is running on port 35729
2022-09-05 00:27:03.091 INFO 20320 --- [ restartedMain] o.s.cloud.commons.util.InetUtils : Cannot determine local hostname
2022-09-05 00:27:03.113 INFO 20320 --- [ restartedMain] o.s.b.a.e.web.EndpointLinksResolver : Exposing 1 endpoint(s) beneath base path '/actuator'
2022-09-05 00:27:03.404 INFO 20320 --- [ restartedMain] o.s.b.w.embedded.tomcat.TomcatWebServer : Tomcat started on port(s): 8002 (http) with context path ''
2022-09-05 00:27:03.437 INFO 20320 --- [ restartedMain] c.a.c.n.registry.NacosServiceRegistry : nacos registry, DEFAULT_GROUP file-manager 192.168.133.1:8002 register finished
2022-09-05 00:27:04.212 INFO 20320 --- [ restartedMain] cn.imcaoxuan.FileManagerApplication : Started FileManagerApplication in 7.241 seconds (JVM running for 8.147)
2022-09-05 00:27:04.688 INFO 20320 --- [(1)-192.168.2.2] com.zaxxer.hikari.HikariDataSource : HikariPool-1 - Starting...
2022-09-05 00:27:04.841 INFO 20320 --- [(1)-192.168.2.2] com.zaxxer.hikari.HikariDataSource : HikariPool-1 - Start completed.
2022-09-05 00:27:04.901 INFO 20320 --- [(3)-192.168.2.2] o.a.c.c.C.[Tomcat].[localhost].[/] : Initializing Spring DispatcherServlet 'dispatcherServlet'
2022-09-05 00:27:04.901 INFO 20320 --- [(3)-192.168.2.2] o.s.web.servlet.DispatcherServlet : Initializing Servlet 'dispatcherServlet'
2022-09-05 00:27:04.903 INFO 20320 --- [(3)-192.168.2.2] o.s.web.servlet.DispatcherServlet : Completed initialization in 2 msGradle 添加私有仓库
Gradle 添加私有仓库
以Android Studio为例
在
build.gradle(Project)中添加maven{...}，如下所示：buildscript { repositories { maven { url "https://maven.imcaoxuan.cn:8443/repository/public/" credentials { username = 'public' password = 'public' } } google() mavenCentral() } dependencies { classpath 'com.android.tools.build:gradle:7.0.4' // NOTE: Do not place your application dependencies here; they belong // in the individual module build.gradle files } }在
settings.gradle(Project)中添加maven{...}，如下所示：dependencyResolutionManagement { repositoriesMode.set(RepositoriesMode.FAIL_ON_PROJECT_REPOS) repositories { maven { url "https://maven.imcaoxuan.cn:8443/repository/public/" credentials { username = 'public' password = 'public' } } google() mavenCentral() jcenter() // Warning: this repository is going to shut down soon } }3.Sync now!
整合代码：TOTP+Hex+Base32
代码引用：org.apache.commons.codec.binary.Base32, org.apache.commons.codec.binary.Hex, TOTP(Johan Rydell, PortWise, Inc)
import javax.crypto.Mac;
import javax.crypto.spec.SecretKeySpec;
import java.lang.reflect.UndeclaredThrowableException;
import java.math.BigInteger;
import java.nio.charset.StandardCharsets;
import java.security.GeneralSecurityException;
import java.util.Arrays;
public class TotpDemo {
private static final int[] DIGITS_POWER
// 0 1 2 3 4 5 6 7 8
= {1, 10, 100, 1000, 10000, 100000, 1000000, 10000000, 100000000};
public static void main(String[] args) {
// todo
String secretKey = "";
Base32 base32 = new Base32();
byte[] bytes = base32.decode(secretKey.toUpperCase());
// [-84, -88, -126, -19, 116, -72, -61, -58, 117, 53]
String hexKey = Hex.encodeHexString(bytes);
String hexTime = Long.toHexString(System.currentTimeMillis() / 30 / 1000);
System.out.println(generateTOTP(hexKey, hexTime, "6"));
}
static class Hex {
public static String encodeHexString(final byte[] data) {
return new String(encodeHex(data));
}
public static char[] encodeHex(final byte[] data) {
return encodeHex(data, true);
}
public static char[] encodeHex(final byte[] data, final boolean toLowerCase) {
return encodeHex(data, toLowerCase ? DIGITS_LOWER : DIGITS_UPPER);
}
protected static char[] encodeHex(final byte[] data, final char[] toDigits) {
final int l = data.length;
final char[] out = new char[l << 1];
// two characters form the hex value.
for (int i = 0, j = 0; i < l; i++) {
out[j++] = toDigits[(0xF0 & data[i]) >>> 4];
out[j++] = toDigits[0x0F & data[i]];
}
return out;
}
private static final char[] DIGITS_LOWER = {'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd',
'e', 'f'};
/**
* Used to build output as Hex
*/
private static final char[] DIGITS_UPPER = {'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D',
'E', 'F'};
}
public static String generateTOTP(String key,
String time,
String returnDigits) {
return generateTOTP(key, time, returnDigits, "HmacSHA1");
}
private static byte[] hmac_sha1(String crypto, byte[] keyBytes,
byte[] text) {
try {
Mac hmac;
hmac = Mac.getInstance(crypto);
SecretKeySpec macKey =
new SecretKeySpec(keyBytes, "RAW");
hmac.init(macKey);
return hmac.doFinal(text);
} catch (GeneralSecurityException gse) {
throw new UndeclaredThrowableException(gse);
}
}
private static byte[] hexStr2Bytes(String hex) {
// Adding one byte to get the right conversion
// values starting with "0" can be converted
byte[] bArray = new BigInteger("10" + hex, 16).toByteArray();
// Copy all the REAL bytes, not the "first"
byte[] ret = new byte[bArray.length - 1];
for (int i = 0; i < ret.length; i++)
ret[i] = bArray[i + 1];
return ret;
}
private static String generateTOTP(String key,
String time,
String returnDigits,
String crypto) {
int codeDigits = Integer.decode(returnDigits).intValue();
String result;
byte[] hash;
// Using the counter
// First 8 bytes are for the movingFactor
// Complaint with base RFC 4226 (HOTP)
while (time.length() < 16)
time = "0" + time;
// Get the HEX in a Byte[]
byte[] msg = hexStr2Bytes(time);
// Adding one byte to get the right conversion
byte[] k = hexStr2Bytes(key);
hash = hmac_sha1(crypto, k, msg);
// put selected bytes into result int
int offset = hash[hash.length - 1] & 0xf;
int binary =
((hash[offset] & 0x7f) << 24) |
((hash[offset + 1] & 0xff) << 16) |
((hash[offset + 2] & 0xff) << 8) |
(hash[offset + 3] & 0xff);
int otp = binary % DIGITS_POWER[codeDigits];
result = Integer.toString(otp);
while (result.length() < codeDigits) {
result = "0" + result;
}
return result;
}
static abstract class BaseNCodec {
static final int EOF = -1;
protected final byte pad;
protected static final int MASK_8BITS = 0xff;
protected static final byte PAD_DEFAULT = '='; // Allow static access to default
private final int unencodedBlockSize;
/**
* Number of bytes in each full block of encoded data, e.g. 3 for Base64 and 8 for Base32
*/
private final int encodedBlockSize;
protected final int lineLength;
/**
* Size of chunk separator. Not used unless {@link #lineLength} > 0.
*/
private final int chunkSeparatorLength;
protected BaseNCodec(final int unencodedBlockSize, final int encodedBlockSize,
final int lineLength, final int chunkSeparatorLength, final byte pad) {
this.unencodedBlockSize = unencodedBlockSize;
this.encodedBlockSize = encodedBlockSize;
final boolean useChunking = lineLength > 0 && chunkSeparatorLength > 0;
this.lineLength = useChunking ? (lineLength / encodedBlockSize) * encodedBlockSize : 0;
this.chunkSeparatorLength = chunkSeparatorLength;
this.pad = pad;
}
public byte[] decode(final String pArray) {
return decode(pArray.getBytes(StandardCharsets.UTF_8));
}
public byte[] decode(final byte[] pArray) {
if (pArray == null || pArray.length == 0) {
return pArray;
}
final Context context = new Context();
decode(pArray, 0, pArray.length, context);
decode(pArray, 0, EOF, context); // Notify decoder of EOF.
final byte[] result = new byte[context.pos];
readResults(result, 0, result.length, context);
return result;
}
abstract void decode(byte[] pArray, int i, int length, Context context);
int readResults(final byte[] b, final int bPos, final int bAvail, final Context context) {
if (context.buffer != null) {
final int len = Math.min(available(context), bAvail);
System.arraycopy(context.buffer, context.readPos, b, bPos, len);
context.readPos += len;
if (context.readPos >= context.pos) {
context.buffer = null; // so hasData() will return false, and this method can return -1
}
return len;
}
return context.eof ? EOF : 0;
}
int available(final Context context) { // package protected for access from I/O streams
return context.buffer != null ? context.pos - context.readPos : 0;
}
protected byte[] ensureBufferSize(int size, Context context) {
if (context.buffer == null) {
context.buffer = new byte[this.getDefaultBufferSize()];
context.pos = 0;
context.readPos = 0;
} else if (context.pos + size - context.buffer.length > 0) {
return resizeBuffer(context, context.pos + size);
}
return context.buffer;
}
protected int getDefaultBufferSize() {
return 8192;
}
private static byte[] resizeBuffer(Context context, int minCapacity) {
int oldCapacity = context.buffer.length;
int newCapacity = oldCapacity * 2;
if (compareUnsigned(newCapacity, minCapacity) < 0) {
newCapacity = minCapacity;
}
if (compareUnsigned(newCapacity, 2147483639) > 0) {
newCapacity = createPositiveCapacity(minCapacity);
}
byte[] b = new byte[newCapacity];
System.arraycopy(context.buffer, 0, b, 0, context.buffer.length);
context.buffer = b;
return b;
}
private static int compareUnsigned(int x, int y) {
return Integer.compare(x + -2147483648, y + -2147483648);
}
private static int createPositiveCapacity(int minCapacity) {
if (minCapacity < 0) {
throw new OutOfMemoryError("Unable to allocate array size: " + ((long) minCapacity & 4294967295L));
} else {
return minCapacity > 2147483639 ? minCapacity : 2147483639;
}
}
protected boolean containsAlphabetOrPad(final byte[] arrayOctet) {
if (arrayOctet == null) {
return false;
}
for (final byte element : arrayOctet) {
if (pad == element || isInAlphabet(element)) {
return true;
}
}
return false;
}
protected abstract boolean isInAlphabet(byte value);
protected static boolean isWhiteSpace(final byte byteToCheck) {
switch (byteToCheck) {
case ' ':
case '\n':
case '\r':
case '\t':
return true;
default:
return false;
}
}
static class Context {
int ibitWorkArea;
long lbitWorkArea;
byte[] buffer;
int pos;
int readPos;
boolean eof;
int currentLinePos;
int modulus;
Context() {
}
public String toString() {
return String.format("%s[buffer=%s, currentLinePos=%s, eof=%s, ibitWorkArea=%s, lbitWorkArea=%s, modulus=%s, pos=%s, readPos=%s]", this.getClass().getSimpleName(), Arrays.toString(this.buffer), this.currentLinePos, this.eof, this.ibitWorkArea, this.lbitWorkArea, this.modulus, this.pos, this.readPos);
}
}
}
static class Base32 extends TotpForXuandembp.BaseNCodec {
private final int decodeSize;
private final int encodeSize;
private final byte[] decodeTable;
private final byte[] encodeTable;
private final byte[] lineSeparator;
private static final int BITS_PER_ENCODED_BYTE = 5;
private static final int BYTES_PER_ENCODED_BLOCK = 8;
private static final int BYTES_PER_UNENCODED_BLOCK = 5;
private static final long MASK_2BITS = 0x03L;
private static final long MASK_7BITS = 0x7fL;
/**
* Mask used to extract 6 bits, used when decoding final trailing character.
*/
private static final long MASK_6BITS = 0x3fL;
/**
* Mask used to extract 5 bits, used when encoding Base32 bytes
*/
private static final int MASK_5BITS = 0x1f;
/**
* Mask used to extract 4 bits, used when decoding final trailing character.
*/
private static final long MASK_4BITS = 0x0fL;
/**
* Mask used to extract 3 bits, used when decoding final trailing character.
*/
private static final long MASK_3BITS = 0x07L;
/** Mask used to extract 2 bits, used when decoding final trailing character. */
/**
* Mask used to extract 1 bits, used when decoding final trailing character.
*/
private static final long MASK_1BITS = 0x01L;
public Base32() {
this(false);
}
public Base32(final boolean useHex) {
this(0, null, useHex, PAD_DEFAULT);
}
public Base32(final int lineLength, final byte[] lineSeparator, final boolean useHex, final byte pad) {
super(BYTES_PER_UNENCODED_BLOCK, BYTES_PER_ENCODED_BLOCK, lineLength,
lineSeparator == null ? 0 : lineSeparator.length, pad);
if (useHex) {
this.encodeTable = HEX_ENCODE_TABLE;
this.decodeTable = HEX_DECODE_TABLE;
} else {
this.encodeTable = ENCODE_TABLE;
this.decodeTable = DECODE_TABLE;
}
if (lineLength > 0) {
if (lineSeparator == null) {
throw new IllegalArgumentException("lineLength " + lineLength + " > 0, but lineSeparator is null");
}
// Must be done after initializing the tables
if (containsAlphabetOrPad(lineSeparator)) {
final String sep = new String(lineSeparator, StandardCharsets.UTF_8);
throw new IllegalArgumentException("lineSeparator must not contain Base32 characters: [" + sep + "]");
}
this.encodeSize = BYTES_PER_ENCODED_BLOCK + lineSeparator.length;
this.lineSeparator = new byte[lineSeparator.length];
System.arraycopy(lineSeparator, 0, this.lineSeparator, 0, lineSeparator.length);
} else {
this.encodeSize = BYTES_PER_ENCODED_BLOCK;
this.lineSeparator = null;
}
this.decodeSize = this.encodeSize - 1;
if (isInAlphabet(pad) || isWhiteSpace(pad)) {
throw new IllegalArgumentException("pad must not be in alphabet or whitespace");
}
}
private static final byte[] HEX_DECODE_TABLE = {
// 0 1 2 3 4 5 6 7 8 9 A B C D E F
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, // 00-0f
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, // 10-1f
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, // 20-2f
0, 1, 2, 3, 4, 5, 6, 7, 8, 9, -1, -1, -1, -1, -1, -1, // 30-3f 2-7
-1, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, // 40-4f A-O
25, 26, 27, 28, 29, 30, 31, // 50-56 P-V
-1, -1, -1, -1, -1, -1, -1, -1, -1, // 57-5f Z-_
-1, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, // 60-6f `-o
25, 26, 27, 28, 29, 30, 31 // 70-76 p-v
};
/**
* This array is a lookup table that translates 5-bit positive integer index values into their
* "Base32 Hex Alphabet" equivalents as specified in Table 4 of RFC 4648.
*/
private static final byte[] HEX_ENCODE_TABLE = {
'0', '1', '2', '3', '4', '5', '6', '7', '8', '9',
'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M',
'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V',
};
private static final byte[] DECODE_TABLE = {
// 0 1 2 3 4 5 6 7 8 9 A B C D E F
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, // 00-0f
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, // 10-1f
-1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, // 20-2f
-1, -1, 26, 27, 28, 29, 30, 31, -1, -1, -1, -1, -1, -1, -1, -1, // 30-3f 2-7
-1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, // 40-4f A-O
15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, // 50-5a P-Z
-1, -1, -1, -1, -1, // 5b - 5f
-1, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, // 60 - 6f a-o
15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, // 70 - 7a p-z/**/
};
/**
* This array is a lookup table that translates 5-bit positive integer index values into their "Base32 Alphabet"
* equivalents as specified in Table 3 of RFC 4648.
*/
private static final byte[] ENCODE_TABLE = {
'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M',
'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z',
'2', '3', '4', '5', '6', '7',
};
private static void validateCharacter(final long emptyBitsMask, final Context context) {
// Use the long bit work area
if ((context.lbitWorkArea & emptyBitsMask) != 0) {
throw new IllegalArgumentException(
"Last encoded character (before the paddings if any) is a valid base 32 alphabet but not a possible value. " +
"Expected the discarded bits to be zero.");
}
}
void decode(final byte[] input, int inPos, final int inAvail, final Context context) {
// package protected for access from I/O streams
if (context.eof) {
return;
}
if (inAvail < 0) {
context.eof = true;
}
for (int i = 0; i < inAvail; i++) {
final byte b = input[inPos++];
if (b == pad) {
// We're done.
context.eof = true;
break;
}
final byte[] buffer = ensureBufferSize(decodeSize, context);
if (b >= 0 && b < this.decodeTable.length) {
final int result = this.decodeTable[b];
if (result >= 0) {
context.modulus = (context.modulus + 1) % BYTES_PER_ENCODED_BLOCK;
// collect decoded bytes
context.lbitWorkArea = (context.lbitWorkArea << BITS_PER_ENCODED_BYTE) + result;
if (context.modulus == 0) { // we can output the 5 bytes
buffer[context.pos++] = (byte) ((context.lbitWorkArea >> 32) & MASK_8BITS);
buffer[context.pos++] = (byte) ((context.lbitWorkArea >> 24) & MASK_8BITS);
buffer[context.pos++] = (byte) ((context.lbitWorkArea >> 16) & MASK_8BITS);
buffer[context.pos++] = (byte) ((context.lbitWorkArea >> 8) & MASK_8BITS);
buffer[context.pos++] = (byte) (context.lbitWorkArea & MASK_8BITS);
}
}
}
}
// Two forms of EOF as far as Base32 decoder is concerned: actual
// EOF (-1) and first time '=' character is encountered in stream.
// This approach makes the '=' padding characters completely optional.
if (context.eof && context.modulus >= 2) { // if modulus < 2, nothing to do
final byte[] buffer = ensureBufferSize(decodeSize, context);
// we ignore partial bytes, i.e. only multiples of 8 count
switch (context.modulus) {
case 2: // 10 bits, drop 2 and output one byte
validateCharacter(MASK_2BITS, context);
buffer[context.pos++] = (byte) ((context.lbitWorkArea >> 2) & MASK_8BITS);
break;
case 3: // 15 bits, drop 7 and output 1 byte
validateCharacter(MASK_7BITS, context);
buffer[context.pos++] = (byte) ((context.lbitWorkArea >> 7) & MASK_8BITS);
break;
case 4: // 20 bits = 2*8 + 4
validateCharacter(MASK_4BITS, context);
context.lbitWorkArea = context.lbitWorkArea >> 4; // drop 4 bits
buffer[context.pos++] = (byte) ((context.lbitWorkArea >> 8) & MASK_8BITS);
buffer[context.pos++] = (byte) ((context.lbitWorkArea) & MASK_8BITS);
break;
case 5: // 25bits = 3*8 + 1
validateCharacter(MASK_1BITS, context);
context.lbitWorkArea = context.lbitWorkArea >> 1;
buffer[context.pos++] = (byte) ((context.lbitWorkArea >> 16) & MASK_8BITS);
buffer[context.pos++] = (byte) ((context.lbitWorkArea >> 8) & MASK_8BITS);
buffer[context.pos++] = (byte) ((context.lbitWorkArea) & MASK_8BITS);
break;
case 6: // 30bits = 3*8 + 6
validateCharacter(MASK_6BITS, context);
context.lbitWorkArea = context.lbitWorkArea >> 6;
buffer[context.pos++] = (byte) ((context.lbitWorkArea >> 16) & MASK_8BITS);
buffer[context.pos++] = (byte) ((context.lbitWorkArea >> 8) & MASK_8BITS);
buffer[context.pos++] = (byte) ((context.lbitWorkArea) & MASK_8BITS);
break;
case 7: // 35 = 4*8 +3
validateCharacter(MASK_3BITS, context);
context.lbitWorkArea = context.lbitWorkArea >> 3;
buffer[context.pos++] = (byte) ((context.lbitWorkArea >> 24) & MASK_8BITS);
buffer[context.pos++] = (byte) ((context.lbitWorkArea >> 16) & MASK_8BITS);
buffer[context.pos++] = (byte) ((context.lbitWorkArea >> 8) & MASK_8BITS);
buffer[context.pos++] = (byte) ((context.lbitWorkArea) & MASK_8BITS);
break;
default:
// modulus can be 0-7, and we excluded 0,1 already
throw new IllegalStateException("Impossible modulus " + context.modulus);
}
}
}
@Override
protected boolean isInAlphabet(byte octet) {
return octet >= 0 && octet < decodeTable.length && decodeTable[octet] != -1;
}
}
}复习：StringBuilder和String拼接字符串效率差距真大
今天在解析一个5M的文本文件时，耗时两分多钟，找了半天才发现原因是使用String += s的方式拼接字符串导致的。
换成StringBuilder后速度提升了4个数量级！
至于原因，大家应该都懂，我就不再赘述了。
基础不能忘！！！
基础不能忘！！！
基础不能忘！！！