'gsonBuilder' defined in class path resource [org/springframework/boot/autoconfigure/gson/GsonAutoC

springboot1.5.X升级2.X 的时候报的错误
这个错误是由于我们把所有公共的工具类都放到了 一个 commons-lang的jar包里面，然后项目只需要依赖这个公共的lang包就可以，不需要在新项目种重复引入一些工具类型的 jar包。例如：gson,utils,commons-lang3,xom等一些工具性质的JAR包。

以下错误就是因为，我自己公共lang包里面引入了，gson,而 springboot2.x之后，他会默认引入一个自己的gson.导致两个gson版本冲突导致的。 而在springboot1.X里面他们是不会默认引入gson包的。

有人会说，那你把自己lang包里面的gson删除了就好了。 但是因为我们这是一个工具类型的模块包，改动或者删除影响太大，有很多项目都在用 相关的JAR包， 所以只能用其他方案。

错误日志：

org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'gsonBuilder' defined in class path resource [org/springframework/boot/autoconfigure/gson/GsonAutoConfiguration.class]: Bean instantiation via factory method failed; nested exception is org.springframework.beans.BeanInstantiationException: Failed to instantiate [com.google.gson.GsonBuilder]: Factory method 'gsonBuilder' threw exception; nested exception is java.lang.BootstrapMethodError: java.lang.NoSuchMethodError: com.google.gson.GsonBuilder.setLenient()Lcom/google/gson/GsonBuilder;
        at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:587)
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateUsingFactoryMethod(AbstractAutowireCapableBeanFactory.java:1250)
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1099)
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:541)
        at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:501)
        at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:317)
        at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:228)
        at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:315)
        at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:199)
        at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:760)
        at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:869)
        at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:550)
        at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:140)
        at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:759)
        at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:395)
        at org.springframework.boot.SpringApplication.run(SpringApplication.java:327)
        at org.springframework.boot.SpringApplication.run(SpringApplication.java:1255)
        at org.springframework.boot.SpringApplication.run(SpringApplication.java:1243)
        at com.caiyouxi.Application.main(Application.java:34)
        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.springframework.boot.loader.MainMethodRunner.run(MainMethodRunner.java:48)
        at org.springframework.boot.loader.Launcher.launch(Launcher.java:87)
        at org.springframework.boot.loader.Launcher.launch(Launcher.java:50)
        at org.springframework.boot.loader.WarLauncher.main(WarLauncher.java:58)
Caused by: org.springframework.beans.BeanInstantiationException: Failed to instantiate [com.google.gson.GsonBuilder]: Factory method 'gsonBuilder' threw exception; nested exception is java.lang.BootstrapMethodError: java.lang.NoSuchMethodError: com.google.gson.GsonBuilder.setLenient()Lcom/google/gson/GsonBuilder;
        at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:185)
        at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:579)
        ... 26 common frames omitted
Caused by: java.lang.BootstrapMethodError: java.lang.NoSuchMethodError: com.google.gson.GsonBuilder.setLenient()Lcom/google/gson/GsonBuilder;
        at org.springframework.boot.autoconfigure.gson.GsonAutoConfiguration$StandardGsonBuilderCustomizer.customize(GsonAutoConfiguration.java:96)
        at org.springframework.boot.autoconfigure.gson.GsonAutoConfiguration.lambda$gsonBuilder$0(GsonAutoConfiguration.java:49)
        at java.util.ArrayList.forEach(ArrayList.java:1255)
        at org.springframework.boot.autoconfigure.gson.GsonAutoConfiguration.gsonBuilder(GsonAutoConfiguration.java:49)
        at org.springframework.boot.autoconfigure.gson.GsonAutoConfiguration$$EnhancerBySpringCGLIB$$4a2f731d.CGLIB$gsonBuilder$0()
        at org.springframework.boot.autoconfigure.gson.GsonAutoConfiguration$$EnhancerBySpringCGLIB$$4a2f731d$$FastClassBySpringCGLIB$$d16133e4.invoke()
        at org.springframework.cglib.proxy.MethodProxy.invokeSuper(MethodProxy.java:228)
        at org.springframework.context.annotation.ConfigurationClassEnhancer$BeanMethodInterceptor.intercept(ConfigurationClassEnhancer.java:361)
        at org.springframework.boot.autoconfigure.gson.GsonAutoConfiguration$$EnhancerBySpringCGLIB$$4a2f731d.gsonBuilder()
        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.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:154)
        ... 27 common frames omitted
Caused by: java.lang.NoSuchMethodError: com.google.gson.GsonBuilder.setLenient()Lcom/google/gson/GsonBuilder;
        at java.lang.invoke.MethodHandleNatives.resolve(Native Method)
        at java.lang.invoke.MemberName$Factory.resolve(MemberName.java:975)
        at java.lang.invoke.MemberName$Factory.resolveOrFail(MemberName.java:1000)
        at java.lang.invoke.MethodHandles$Lookup.resolveOrFail(MethodHandles.java:1394)
        at java.lang.invoke.MethodHandles$Lookup.linkMethodHandleConstant(MethodHandles.java:1750)
        at java.lang.invoke.MethodHandleNatives.linkMethodHandleConstant(MethodHandleNatives.java:477)
        ... 41 common frames omitted

解决方案：
启动类（Application）中添加
@EnableAutoConfiguration(exclude = {org.springframework.boot.autoconfigure.gson.GsonAutoConfiguration.class})
注解。

@EnableAutoConfiguration(exclude = {org.springframework.boot.autoconfigure.gson.GsonAutoConfiguration.class})
@SpringBootApplication
//开启事务
@EnableTransactionManagement
@EnableScheduling
public class Application extends SpringBootServletInitializer {
    private static Logger logger = Logger.getLogger(Application.class);

    @Override
    protected SpringApplicationBuilder configure(SpringApplicationBuilder application) {
        return application.sources(Application.class);
    }

    /**
     * Start
     */
    public static void main(String[] args) {
    	logger.info("service Server Start ---");
        SpringApplication.run(Application.class, args);
        logger.info("service Server Start Success---");
    }

}

这个问题是由于GSON库的版本与项目中已经包含的现有依赖项与SpringBoot的默认依赖项的版本不匹配而产生的。
它基本上告诉SpringBoot应用程序跳过GSON的自动配置。
这个解决方案也适用于任何其他可能产生相同问题的类。您只需要将每个此类冲突类的名称添加到EnableCautoconfiguration的exclude属性中。

I faced the same problem and had to waste a lot of time trying to fix this.

The problem arises due to the version mismatch of the Gson library from existing dependencies already included in your project with that of Spring Boot’s default one.

The easiest fix of this problem (that worked for me) is to replace each occurrence of the

@EnableAutoConfiguration

tag with

@EnableAutoConfiguration(exclude = {org.springframework.boot.autoconfigure.gson.GsonAutoConfiguration.class})

which basically tells the Spring boot application to skip auto configuration for Gson.

This solution also applies to any other class that might create the same problem. You just need to add the name of each such conflicting class to the exclude attribute of EnableAutoConfiguration.

原答案路径：
Why do I get Gson builder error when starting a Spring Boot application?