Inefficient Usages of Java Collections

[FastAtlas]

Hi,

We find that there are several inefficient usages of Java Collections:

1. The contains method is invoked upon a list object in a loop. We recommend replacing it with a HashSet.
2. Random access can occur at several LinkedList objects, which run in linear time complexity. We recommend replacing them with Arraylist objects.
3. There is no iteration occurring upon a LinkedHashMap and LinkedHashSet, thus the insertion order does not matter. We recommend replacing it with a HashMap and HashSet.
4. ArrayList is inserted before an iteration, while multiple memory reallocation might occur when the size of the list exceeds its capacity. We recommend replacing it with a LinkedList.

We discovered the above inefficient usage of containers by our tool Ditto. The patch is submitted. Could you please check and accept it? We have tested the patch on our PC. The patched program works well.

Bests

Ditto

[mercyblitz]

Please fix the checkstyle issue first, thanks.

[codecov-commenter]

Codecov Report

Merging #8784 (2bb3ba8) into 3.0 (5c2161a) will decrease coverage by 0.00%.
The diff coverage is 52.94%.

@@             Coverage Diff              @@
##                3.0    #8784      +/-   ##
============================================
- Coverage     63.92%   63.92%   -0.01%     
+ Complexity      315      314       -1     
============================================
  Files          1156     1156              
  Lines         48702    48703       +1     
  Branches       7324     7324              
============================================
  Hits          31134    31134              
- Misses        14175    14177       +2     
+ Partials       3393     3392       -1     

Impacted Files	Coverage Δ
...figcenter/file/FileSystemDynamicConfiguration.java	0.00% <0.00%> (ø)
.../apache/dubbo/config/bootstrap/DubboBootstrap.java	53.40% <ø> (ø)
...n/serialize/support/SerializableClassRegistry.java	0.00% <0.00%> (ø)
...ate/endpoint/metadata/DubboReferencesMetadata.java	5.55% <0.00%> (ø)
...factory/config/ServiceBeanIdConflictProcessor.java	0.00% <0.00%> (ø)
...apache/dubbo/common/extension/ExtensionLoader.java	81.71% <71.42%> (+0.23%)	⬆️
...c/cluster/router/mesh/rule/VsDestinationGroup.java	100.00% <100.00%> (ø)
.../java/org/apache/dubbo/common/utils/TypeUtils.java	70.27% <100.00%> (ø)
...main/java/org/apache/dubbo/qos/textui/TLadder.java	100.00% <100.00%> (ø)
...ng/transport/dispatcher/all/AllChannelHandler.java	89.65% <0.00%> (-6.90%)	⬇️
... and 12 more

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