[ISSUE #11231]Optimize the handleSpringBinder method in PropertiesUtil.

[stone-98]

What is the purpose of the change

The Nacos source code startup results in an error as follows:

2023-10-09 21:26:50.729  WARN 4688 --- [           main] c.a.n.c.s.c.ConfigChangeConfigs          : [ConfigChangeConfigs]Refresh config plugin properties failed 

java.lang.reflect.InvocationTargetException: null
	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 com.alibaba.nacos.sys.utils.PropertiesUtil.handleSpringBinder(PropertiesUtil.java:62)
	at com.alibaba.nacos.sys.utils.PropertiesUtil.getPropertiesWithPrefix(PropertiesUtil.java:35)
	at com.alibaba.nacos.config.server.configuration.ConfigChangeConfigs.refreshPluginProperties(ConfigChangeConfigs.java:56)
	at com.alibaba.nacos.config.server.configuration.ConfigChangeConfigs.<init>(ConfigChangeConfigs.java:50)
	at com.alibaba.nacos.config.server.configuration.ConfigChangeConfigs$$EnhancerBySpringCGLIB$$fb3b6b82.<init>(<generated>)
	at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
	at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
	at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
	at java.lang.reflect.Constructor.newInstance(Constructor.java:423)
	at org.springframework.beans.BeanUtils.instantiateClass(BeanUtils.java:211)
	at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:87)
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateBean(AbstractAutowireCapableBeanFactory.java:1326)
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1232)
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:582)
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:542)
	at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:335)
	at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:234)
	at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:333)
	at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:208)
	at org.springframework.beans.factory.config.DependencyDescriptor.resolveCandidate(DependencyDescriptor.java:276)
	at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1391)
	at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1311)
	at org.springframework.beans.factory.support.ConstructorResolver.resolveAutowiredArgument(ConstructorResolver.java:887)
	at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:791)
	at org.springframework.beans.factory.support.ConstructorResolver.autowireConstructor(ConstructorResolver.java:229)
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.autowireConstructor(AbstractAutowireCapableBeanFactory.java:1372)
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1222)
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:582)
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:542)
	at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:335)
	at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:234)
	at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:333)
	at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:208)
	at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:955)
	at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:921)
	at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:583)
	at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:147)
	at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:731)
	at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:408)
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:307)
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:1303)
	at org.springframework.boot.SpringApplication.run(SpringApplication.java:1292)
	at com.alibaba.nacos.Nacos.main(Nacos.java:48)
Caused by: java.util.NoSuchElementException: No value bound
	at org.springframework.boot.context.properties.bind.BindResult.get(BindResult.java:55)
	... 47 common frames omitted

Reason: The Nacos source code by default does not have configuration related to change plugins (nacos.core.config.plugin.*).

Below is the source code related to BindResult:

public final class BindResult<T> {
    ...
    public T get() throws NoSuchElementException {
        if (this.value == null) {
            throw new NoSuchElementException("No value bound");
        } else {
            return this.value;
        }
    }

    public T orElse(T other) {
        return this.value != null ? this.value : other;
    }
   ...
}

Brief changelog

• Change the previous approach of using reflection calls to using object-based invocations.

• Replace the previous usage of the BindResult#get() method with BindResult#orElse method, which defaults to returning null if not present. Then, perform null-check handling at the outer layer.

Verifying this change

Enable authentication plugin

Before the modification

Authentication plugin reads the content

After the modification

Fix the error in the configuration change plugin.

Authentication-related property content

Consistent with the content before the change.

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• Write necessary unit-test to verify your logic correction, more mock a little better when cross module dependency exist. If the new feature or significant change is committed, please remember to add integration-test in test module.
• Run mvn -B clean package apache-rat:check findbugs:findbugs -Dmaven.test.skip=true to make sure basic checks pass. Run mvn clean install -DskipITs to make sure unit-test pass. Run mvn clean test-compile failsafe:integration-test to make sure integration-test pass.

[codecov-commenter]

Codecov Report

Merging #11240 (11220ca) into develop (7911eb0) will increase coverage by 0.08%.
The diff coverage is 85.71%.

Additional details and impacted files

@@              Coverage Diff              @@
##             develop   #11240      +/-   ##
=============================================
+ Coverage      53.97%   54.05%   +0.08%     
+ Complexity      5580     5579       -1     
=============================================
  Files            907      907              
  Lines          28844    28838       -6     
  Branches        3191     3192       +1     
=============================================
+ Hits           15568    15589      +21     
+ Misses         11933    11902      -31     
- Partials        1343     1347       +4     

Files	Coverage Δ
...va/com/alibaba/nacos/sys/utils/PropertiesUtil.java	60.00% <100.00%> (-21.82%)	⬇️
...ava/com/alibaba/nacos/auth/config/AuthConfigs.java	60.65% <90.00%> (-1.02%)	⬇️
...baba/nacos/core/remote/tls/RpcServerTlsConfig.java	68.75% <66.66%> (+4.04%)	⬆️

... and 5 files with indirect coverage changes

---

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