rename ClassHelper to ClassUtils, add MethodUtils

[LiZhenNet]

What is the purpose of the change

rename ClassHelper to ClassUtils

Brief changelog

1. add ClassUtils to replace ClassHelper , ClassHelper add deprecated annotation.
2. add MethodUtils, move isSetter/isGetter into it.

Next step :
Merging
org.apache.dubbo.common.compiler.support.ClassUtils,
org.apache.dubbo.config.spring.util.ClassUtils,
org.apache.dubbo.metadata.definition.util.ClassUtils,

Verifying this change

UT

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[ralf0131]

I have some questions:

1. Why do we need such a change?
2. What is the difference between org.apache.dubbo.common.compiler.support.ClassUtils and org.apache.dubbo.common.utils.ClassUtils?

[LiZhenNet]

I have some questions:

1. Why do we need such a change?
2. What is the difference between org.apache.dubbo.common.compiler.support.ClassUtils and org.apache.dubbo.common.utils.ClassUtils?

1. I think ClassHelper is not standard in Dubbo, and It has some methods on Method.class.
2. Some of these two classes are the same, Are we considering merging them?

[ralf0131]

1. I think ClassHelper is not standard in Dubbo, and It has some methods on Method.class.
2. Some of these two classes are the same, Are we considering merging them?

If they are duplicated, I think it is better to merge them. How do you think? Are you planning to do it next, or in this pull request?

[ralf0131]

All the UT are failing, could you please check about that?

[codecov-io]

Codecov Report

Merging #3806 into master will decrease coverage by 0.05%.
The diff coverage is 61.29%.

@@             Coverage Diff              @@
##             master    #3806      +/-   ##
============================================
- Coverage     63.97%   63.92%   -0.06%     
  Complexity       98       98              
============================================
  Files           713      715       +2     
  Lines         31481    31497      +16     
  Branches       5076     5076              
============================================
- Hits          20139    20133       -6     
- Misses         9038     9057      +19     
- Partials       2304     2307       +3

Impacted Files	Coverage Δ	Complexity Δ
...che/dubbo/common/compiler/support/JdkCompiler.java	64.54% <0%> (ø)	0 <0> (ø)	⬇️
...ava/org/apache/dubbo/common/utils/ClassHelper.java	0% <0%> (-69.1%)	0 <0> (ø)
...ubbo/common/compiler/support/AbstractCompiler.java	72.72% <0%> (ø)	0 <0> (ø)	⬇️
...in/java/org/apache/dubbo/config/ServiceConfig.java	58.08% <0%> (ø)	0 <0> (ø)	⬇️
.../java/org/apache/dubbo/config/ReferenceConfig.java	60.07% <0%> (ø)	0 <0> (ø)	⬇️
...mon/serialize/java/CompactedObjectInputStream.java	64.28% <0%> (ø)	0 <0> (ø)	⬇️
...rg/apache/dubbo/common/timer/HashedWheelTimer.java	58.62% <0%> (ø)	0 <0> (ø)	⬇️
...java/org/apache/dubbo/common/bytecode/Wrapper.java	82.38% <100%> (ø)	0 <0> (ø)	⬇️
.../java/org/apache/dubbo/common/utils/PojoUtils.java	70.43% <100%> (ø)	0 <0> (ø)	⬇️
...ava/org/apache/dubbo/common/utils/ConfigUtils.java	80% <100%> (ø)	0 <0> (ø)	⬇️
... and 20 more

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[LiZhenNet]

All the UT are failing, could you please check about that?

Sorry for late ,I have fixed it .

[LiZhenNet]

@ralf0131
Is there any progress？

[ralf0131]

LGTM, thanks for the pull request.