diff --git a/.idea/compiler.xml b/.idea/compiler.xml
index 84dcfc60e9..450847bd62 100644
--- a/.idea/compiler.xml
+++ b/.idea/compiler.xml
@@ -2,73 +2,72 @@
 <project version="4">
   <component name="CompilerConfiguration">
     <annotationProcessing>
+      <profile default="true" name="Default" enabled="true" />
       <profile name="Maven default annotation processors profile" enabled="true">
         <sourceOutputDir name="target/generated-sources/annotations" />
         <sourceTestOutputDir name="target/generated-test-sources/test-annotations" />
         <outputRelativeToContentRoot value="true" />
-        <module name="jmh" />
         <module name="assertion-libraries" />
-        <module name="cucumber" />
         <module name="core-java-annotations" />
-        <module name="jackson-simple" />
-        <module name="spring-testing-2" />
-        <module name="test-containers" />
-        <module name="mockserver" />
-        <module name="spring-testing" />
-        <module name="xml" />
-        <module name="core-java-datetime-conversion" />
-        <module name="testing-libraries" />
-        <module name="mocks" />
-        <module name="load-testing-comparison" />
-        <module name="junit-5-basics" />
-        <module name="mockito-2" />
-        <module name="testing-assertions" />
-        <module name="easymock" />
+        <module name="codebank" />
         <module name="core-java-collections-list" />
         <module name="junit5-migration" />
-        <module name="core-java-io" />
-        <module name="easy-random" />
-        <module name="junit-5" />
-        <module name="junit-4" />
-        <module name="junit-5-advanced" />
-        <module name="rest-testing" />
-        <module name="jackson-exceptions" />
-        <module name="core-java-8" />
-        <module name="jackson-conversions" />
-        <module name="math-test-functions" />
-        <module name="java-numbers-2" />
-        <module name="jackson-annotations" />
-        <module name="java-numbers" />
-        <module name="mockito" />
-        <module name="jackson" />
-        <module name="groovy-spock" />
-        <module name="jackson-conversions-2" />
-        <module name="codebank" />
-        <module name="selenium-junit-testng" />
-        <module name="junit5-annotations" />
-        <module name="mockito-3" />
-        <module name="powermock" />
-        <module name="zerocode" />
-        <module name="gatling" />
         <module name="discourse" />
-        <module name="rest-assured" />
-        <module name="jackson-custom-conversions" />
-        <module name="testing-libraries-2" />
-        <module name="string-test-functions" />
-        <module name="xmlunit-2" />
-        <module name="testng" />
-        <module name="hamcrest" />
+        <module name="core-java-8" />
       </profile>
     </annotationProcessing>
+    <bytecodeTargetLevel>
+      <module name="cucumber" target="14" />
+      <module name="easy-random" target="11" />
+      <module name="easymock" target="1.5" />
+      <module name="gatling" target="1.8" />
+      <module name="groovy-spock" target="11" />
+      <module name="hamcrest" target="1.5" />
+      <module name="jackson" target="11" />
+      <module name="jackson-annotations" target="11" />
+      <module name="jackson-conversions" target="11" />
+      <module name="jackson-conversions-2" target="11" />
+      <module name="jackson-custom-conversions" target="11" />
+      <module name="jackson-exceptions" target="11" />
+      <module name="jackson-modules" target="11" />
+      <module name="jackson-simple" target="11" />
+      <module name="java-numbers" target="11" />
+      <module name="java-numbers-2" target="11" />
+      <module name="jmh" target="11" />
+      <module name="junit-4" target="1.5" />
+      <module name="junit-5" target="11" />
+      <module name="junit-5-advanced" target="11" />
+      <module name="junit-5-basics" target="11" />
+      <module name="junit5-annotations" target="11" />
+      <module name="load-testing-comparison" target="1.8" />
+      <module name="math-test-functions" target="1.5" />
+      <module name="mockito" target="1.5" />
+      <module name="mockito-2" target="11" />
+      <module name="mockito-3" target="1.5" />
+      <module name="mocks" target="1.5" />
+      <module name="mockserver" target="11" />
+      <module name="parallel-tests-junit" target="1.5" />
+      <module name="parent-java" target="11" />
+      <module name="powermock" target="1.5" />
+      <module name="rest-assured" target="11" />
+      <module name="rest-testing" target="11" />
+      <module name="selenium-junit-testng" target="1.5" />
+      <module name="spring-testing" target="11" />
+      <module name="spring-testing-2" target="11" />
+      <module name="string-test-functions" target="1.5" />
+      <module name="test-containers" target="1.5" />
+      <module name="testing-assertions" target="1.5" />
+      <module name="testing-libraries" target="1.5" />
+      <module name="testing-libraries-2" target="1.5" />
+      <module name="testng" target="1.5" />
+      <module name="xml" target="11" />
+      <module name="xmlunit-2" target="1.5" />
+      <module name="zerocode" target="8" />
+    </bytecodeTargetLevel>
   </component>
   <component name="JavacSettings">
     <option name="ADDITIONAL_OPTIONS_OVERRIDE">
-      <module name="codebank" options="" />
-      <module name="discourse" options="" />
-      <module name="java-numbers" options="" />
-      <module name="java-numbers-2" options="" />
       <module name="jmh" options="--add-exports java.base/jdk.internal.vm.annotation=ALL-UNNAMED" />
-      <module name="xml" options="" />
     </option>
   </component>
 </project>
\ No newline at end of file
diff --git a/.idea/encodings.xml b/.idea/encodings.xml
index 1c11104ab2..98fdcc816b 100644
--- a/.idea/encodings.xml
+++ b/.idea/encodings.xml
@@ -7,10 +7,6 @@
     <file url="file://$PROJECT_DIR$/core-java-modules/core-java-annotations/src/main/resources" charset="UTF-8" />
     <file url="file://$PROJECT_DIR$/core-java-modules/core-java-collections-list/src/main/java" charset="UTF-8" />
     <file url="file://$PROJECT_DIR$/core-java-modules/core-java-collections-list/src/main/resources" charset="UTF-8" />
-    <file url="file://$PROJECT_DIR$/core-java-modules/core-java-datetime-conversion/src/main/java" charset="UTF-8" />
-    <file url="file://$PROJECT_DIR$/core-java-modules/core-java-datetime-conversion/src/main/resources" charset="UTF-8" />
-    <file url="file://$PROJECT_DIR$/core-java-modules/core-java-io/src/main/java" charset="UTF-8" />
-    <file url="file://$PROJECT_DIR$/core-java-modules/core-java-io/src/main/resources" charset="UTF-8" />
     <file url="file://$PROJECT_DIR$/core-java-modules/src/main/java" charset="UTF-8" />
     <file url="file://$PROJECT_DIR$/core-java-modules/src/main/resources" charset="UTF-8" />
     <file url="file://$PROJECT_DIR$/jackson-modules/jackson-annotations/src/main/java" charset="UTF-8" />
@@ -39,17 +35,33 @@
     <file url="file://$PROJECT_DIR$/parent-java/src/main/resources" charset="UTF-8" />
     <file url="file://$PROJECT_DIR$/src/main/java" charset="UTF-8" />
     <file url="file://$PROJECT_DIR$/src/main/resources" charset="UTF-8" />
+    <file url="file://$PROJECT_DIR$/testing-modules/assertion-libraries/src/main/java" charset="UTF-8" />
+    <file url="file://$PROJECT_DIR$/testing-modules/assertion-libraries/src/main/resources" charset="UTF-8" />
     <file url="file://$PROJECT_DIR$/testing-modules/easy-random/src/main/java" charset="UTF-8" />
     <file url="file://$PROJECT_DIR$/testing-modules/easy-random/src/main/resources" charset="UTF-8" />
+    <file url="file://$PROJECT_DIR$/testing-modules/groovy-spock/src/main/java" charset="UTF-8" />
+    <file url="file://$PROJECT_DIR$/testing-modules/groovy-spock/src/main/resources" charset="UTF-8" />
+    <file url="file://$PROJECT_DIR$/testing-modules/junit-5-advanced/src/main/java" charset="UTF-8" />
+    <file url="file://$PROJECT_DIR$/testing-modules/junit-5-advanced/src/main/resources" charset="UTF-8" />
     <file url="file://$PROJECT_DIR$/testing-modules/junit-5-basics/src/main/java" charset="UTF-8" />
     <file url="file://$PROJECT_DIR$/testing-modules/junit-5-basics/src/main/resources" charset="UTF-8" />
     <file url="file://$PROJECT_DIR$/testing-modules/junit-5-basics/src/test/resources" charset="UTF-8" />
+    <file url="file://$PROJECT_DIR$/testing-modules/junit-5/src/main/java" charset="UTF-8" />
+    <file url="file://$PROJECT_DIR$/testing-modules/junit-5/src/test/resources" charset="UTF-8" />
+    <file url="file://$PROJECT_DIR$/testing-modules/junit5-annotations/src/main/java" charset="UTF-8" />
+    <file url="file://$PROJECT_DIR$/testing-modules/junit5-annotations/src/main/resources" charset="UTF-8" />
+    <file url="file://$PROJECT_DIR$/testing-modules/junit5-migration/src/main/java" charset="UTF-8" />
+    <file url="file://$PROJECT_DIR$/testing-modules/junit5-migration/src/test/resources" charset="UTF-8" />
     <file url="file://$PROJECT_DIR$/testing-modules/mockito-2/src/main/java" charset="UTF-8" />
     <file url="file://$PROJECT_DIR$/testing-modules/mockito-2/src/main/resources" charset="UTF-8" />
     <file url="file://$PROJECT_DIR$/testing-modules/mockserver/src/main/java" charset="UTF-8" />
     <file url="file://$PROJECT_DIR$/testing-modules/mockserver/src/main/resources" charset="UTF-8" />
+    <file url="file://$PROJECT_DIR$/testing-modules/rest-assured/src/main/java" charset="UTF-8" />
+    <file url="file://$PROJECT_DIR$/testing-modules/rest-assured/src/main/resources" charset="UTF-8" />
     <file url="file://$PROJECT_DIR$/testing-modules/rest-testing/src/main/java" charset="UTF-8" />
     <file url="file://$PROJECT_DIR$/testing-modules/rest-testing/src/main/resources" charset="UTF-8" />
+    <file url="file://$PROJECT_DIR$/testing-modules/spring-testing-2/src/main/java" charset="UTF-8" />
+    <file url="file://$PROJECT_DIR$/testing-modules/spring-testing-2/src/main/resources" charset="UTF-8" />
     <file url="file://$PROJECT_DIR$/testing-modules/spring-testing/src/main/java" charset="UTF-8" />
     <file url="file://$PROJECT_DIR$/testing-modules/spring-testing/src/main/resources" charset="UTF-8" />
     <file url="file://$PROJECT_DIR$/testing-modules/src/main/java" charset="UTF-8" />
diff --git a/.idea/jarRepositories.xml b/.idea/jarRepositories.xml
index b74a7f7384..712ab9d985 100644
--- a/.idea/jarRepositories.xml
+++ b/.idea/jarRepositories.xml
@@ -6,11 +6,6 @@
       <option name="name" value="Central Repository" />
       <option name="url" value="https://repo.maven.apache.org/maven2" />
     </remote-repository>
-    <remote-repository>
-      <option name="id" value="m2-ossez-com-m2" />
-      <option name="name" value="m2-ossez-com-m2" />
-      <option name="url" value="https://m2-ossez-com-206755003006.d.codeartifact.us-east-2.amazonaws.com/maven/m2/" />
-    </remote-repository>
     <remote-repository>
       <option name="id" value="central" />
       <option name="name" value="Maven Central repository" />
diff --git a/.idea/jpa-buddy.xml b/.idea/jpa-buddy.xml
deleted file mode 100644
index d08f40080c..0000000000
--- a/.idea/jpa-buddy.xml
+++ /dev/null
@@ -1,6 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<project version="4">
-  <component name="JpaBuddyIdeaProjectConfig">
-    <option name="defaultUnitInitialized" value="true" />
-  </component>
-</project>
\ No newline at end of file
diff --git a/.idea/misc.xml b/.idea/misc.xml
index d31b37ac7b..44c4c0bfc4 100644
--- a/.idea/misc.xml
+++ b/.idea/misc.xml
@@ -5,6 +5,9 @@
     <option name="originalFiles">
       <list>
         <option value="$PROJECT_DIR$/pom.xml" />
+        <option value="$PROJECT_DIR$/testing-modules/pom.xml" />
+        <option value="$PROJECT_DIR$/core-java-modules/pom.xml" />
+        <option value="$PROJECT_DIR$/testing-modules/junit5-migration/pom.xml" />
       </list>
     </option>
   </component>
diff --git a/.idea/vcs.xml b/.idea/vcs.xml
index 94a25f7f4c..35eb1ddfbb 100644
--- a/.idea/vcs.xml
+++ b/.idea/vcs.xml
@@ -1,6 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <project version="4">
   <component name="VcsDirectoryMappings">
-    <mapping directory="$PROJECT_DIR$" vcs="Git" />
+    <mapping directory="" vcs="Git" />
   </component>
 </project>
\ No newline at end of file
diff --git a/.idea/workspace.xml b/.idea/workspace.xml
index 1447102d06..f109c1626f 100644
--- a/.idea/workspace.xml
+++ b/.idea/workspace.xml
@@ -4,8 +4,20 @@
     <option name="autoReloadType" value="SELECTIVE" />
   </component>
   <component name="ChangeListManager">
-    <list default="true" id="2a855b03-5ee0-4324-b916-110994784a14" name="Changes" comment="Update the document link">
-      <change afterPath="$PROJECT_DIR$/core-java-modules/core-java-collections-list/src/test/java/com/ossez/list/RemoveFirstElementTest.java" afterDir="false" />
+    <list default="true" id="080575e3-7e62-4649-ae70-06fb6130a866" name="Changes" comment="提交所有代码，为将默认分支名从 master 切换到 main 做准备">
+      <change beforePath="$PROJECT_DIR$/.idea/compiler.xml" beforeDir="false" afterPath="$PROJECT_DIR$/.idea/compiler.xml" afterDir="false" />
+      <change beforePath="$PROJECT_DIR$/.idea/encodings.xml" beforeDir="false" afterPath="$PROJECT_DIR$/.idea/encodings.xml" afterDir="false" />
+      <change beforePath="$PROJECT_DIR$/.idea/jarRepositories.xml" beforeDir="false" afterPath="$PROJECT_DIR$/.idea/jarRepositories.xml" afterDir="false" />
+      <change beforePath="$PROJECT_DIR$/.idea/jpa-buddy.xml" beforeDir="false" />
+      <change beforePath="$PROJECT_DIR$/.idea/misc.xml" beforeDir="false" afterPath="$PROJECT_DIR$/.idea/misc.xml" afterDir="false" />
+      <change beforePath="$PROJECT_DIR$/.idea/vcs.xml" beforeDir="false" afterPath="$PROJECT_DIR$/.idea/vcs.xml" afterDir="false" />
+      <change beforePath="$PROJECT_DIR$/.idea/workspace.xml" beforeDir="false" afterPath="$PROJECT_DIR$/.idea/workspace.xml" afterDir="false" />
+      <change beforePath="$PROJECT_DIR$/jackson-modules/pom.xml" beforeDir="false" afterPath="$PROJECT_DIR$/jackson-modules/pom.xml" afterDir="false" />
+      <change beforePath="$PROJECT_DIR$/pom.xml" beforeDir="false" afterPath="$PROJECT_DIR$/pom.xml" afterDir="false" />
+      <change beforePath="$PROJECT_DIR$/src/test/java/com/ossez/codebank/algorithm/tests/VariableTest.java" beforeDir="false" afterPath="$PROJECT_DIR$/src/test/java/com/ossez/codebank/algorithm/tests/VariableTest.java" afterDir="false" />
+      <change beforePath="$PROJECT_DIR$/testing-modules/junit-5-basics/pom.xml" beforeDir="false" afterPath="$PROJECT_DIR$/testing-modules/junit-5-basics/pom.xml" afterDir="false" />
+      <change beforePath="$PROJECT_DIR$/toolkits/codebank/pom.xml" beforeDir="false" afterPath="$PROJECT_DIR$/toolkits/codebank/pom.xml" afterDir="false" />
+      <change beforePath="$PROJECT_DIR$/toolkits/codebank/src/test/java/com/ossez/toolkits/codebank/tests/BitOperationTest.java" beforeDir="false" afterPath="$PROJECT_DIR$/toolkits/codebank/src/test/java/com/ossez/toolkits/codebank/tests/BitOperationTest.java" afterDir="false" />
     </list>
     <option name="SHOW_DIALOG" value="false" />
     <option name="HIGHLIGHT_CONFLICTS" value="true" />
@@ -18,362 +30,278 @@
   <component name="Git.Settings">
     <option name="RECENT_GIT_ROOT_PATH" value="$PROJECT_DIR$" />
   </component>
-  <component name="GitSEFilterConfiguration">
-    <file-type-list>
-      <filtered-out-file-type name="LOCAL_BRANCH" />
-      <filtered-out-file-type name="REMOTE_BRANCH" />
-      <filtered-out-file-type name="TAG" />
-      <filtered-out-file-type name="COMMIT_BY_MESSAGE" />
-    </file-type-list>
-  </component>
-  <component name="JpbToolWindowState">
-    <option name="myId2FirstActivated">
-      <map>
-        <entry key="JPA Structure" value="true" />
-        <entry key="com.haulmont.jpb.jpaPalette" value="true" />
-        <entry key="com.haulmont.jpb.jpaStructure" value="true" />
-      </map>
-    </option>
-    <option name="myId2Visible">
-      <map>
-        <entry key="JPA Structure" value="false" />
-        <entry key="com.haulmont.jpb.jpaPalette" value="false" />
-        <entry key="com.haulmont.jpb.jpaStructure" value="false" />
-      </map>
-    </option>
+  <component name="HighlightingSettingsPerFile">
+    <setting file="file://$PROJECT_DIR$/core-java-modules/core-java-collections-list/src/test/resources/logback.xml" root0="FORCE_HIGHLIGHTING" />
+    <setting file="file://$PROJECT_DIR$/core-java-modules/core-java-collections-list/src/test/java/com/ossez/list/RemoveFirstElementTest.java" root0="FORCE_HIGHLIGHTING" />
+    <setting file="file://$PROJECT_DIR$/core-java-modules/core-java-collections-list/src/test/java/com/ossez/list/random/RandomListElementUnitTest.java" root0="FORCE_HIGHLIGHTING" />
+    <setting file="file://$PROJECT_DIR$/toolkits/codebank/src/test/resources/log4j2.xml" root0="FORCE_HIGHLIGHTING" />
+    <setting file="file://$PROJECT_DIR$/core-java-modules/pom.xml" root0="FORCE_HIGHLIGHTING" />
+    <setting file="file://$PROJECT_DIR$/core-java-modules/core-java-collections-list/pom.xml" root0="FORCE_HIGHLIGHTING" />
+    <setting file="file://$PROJECT_DIR$/src/test/resources/log4j2.xml" root0="FORCE_HIGHLIGHTING" />
+    <setting file="file://$PROJECT_DIR$/testing-modules/junit-5-advanced/src/test/resources/junit-platform.properties" root0="FORCE_HIGHLIGHTING" />
   </component>
   <component name="MarkdownSettingsMigration">
     <option name="stateVersion" value="1" />
   </component>
-  <component name="MavenRunner">
-    <option name="skipTests" value="true" />
+  <component name="MavenImportPreferences">
+    <option name="generalSettings">
+      <MavenGeneralSettings>
+        <option name="useMavenConfig" value="true" />
+      </MavenGeneralSettings>
+    </option>
   </component>
-  <component name="ProjectId" id="1yXq0B5lme8eyBDkbRBUHlwFMj2" />
+  <component name="ProjectId" id="28NaD4KRCPKHeUH5DxePmSU7br2" />
   <component name="ProjectViewState">
     <option name="hideEmptyMiddlePackages" value="true" />
     <option name="showLibraryContents" value="true" />
   </component>
   <component name="PropertiesComponent">
-    <property name="DatabaseDriversLRU" value="mariadb" />
+    <property name="Git.Branch.Popup.ShowAllRemotes" value="true" />
     <property name="RunOnceActivity.OpenProjectViewOnStart" value="true" />
     <property name="RunOnceActivity.ShowReadmeOnStart" value="true" />
-    <property name="SHARE_PROJECT_CONFIGURATION_FILES" value="true" />
     <property name="TF_FMT" value="false" />
     <property name="WebServerToolWindowFactoryState" value="false" />
-    <property name="last_opened_file_path" value="$PROJECT_DIR$/src/test/java/com/ossez/codebank/algorithm/tests" />
+    <property name="go.format.on.save.advertiser.fired" value="true" />
+    <property name="go.formatter.settings.were.checked" value="true" />
+    <property name="go.import.settings.migrated" value="true" />
+    <property name="last_opened_file_path" value="$PROJECT_DIR$/core-java-modules/core-java-collections-list/src/test/resources" />
     <property name="node.js.detected.package.eslint" value="true" />
     <property name="node.js.detected.package.tslint" value="true" />
     <property name="node.js.selected.package.eslint" value="(autodetect)" />
     <property name="node.js.selected.package.tslint" value="(autodetect)" />
-    <property name="nodejs_package_manager_path" value="npm" />
-    <property name="project.structure.last.edited" value="Modules" />
-    <property name="project.structure.proportion" value="0.13908207" />
-    <property name="project.structure.side.proportion" value="0.24043715" />
+    <property name="project.structure.last.edited" value="Project" />
+    <property name="project.structure.proportion" value="0.0" />
+    <property name="project.structure.side.proportion" value="0.0" />
     <property name="settings.editor.selected.configurable" value="MavenSettings" />
   </component>
   <component name="RecentsManager">
     <key name="CopyFile.RECENT_KEYS">
-      <recent name="D:\WorkDir\Repository\GitHub\cwiki-us-docs\java-tutorials\src\test\java\com\ossez\codebank\algorithm\tests" />
-      <recent name="D:\WorkDir\Repository\GitHub\cwiki-us-docs\java-tutorials\parent-java" />
-      <recent name="D:\WorkDir\Repository\GitHub\cwiki-us-docs\java-tutorials\xml\src\test\resources" />
-      <recent name="D:\WorkDir\Repository\GitHub\cwiki-us-docs\java-tutorials" />
-    </key>
-    <key name="CopyClassDialog.RECENTS_KEY">
-      <recent name="com.baeldung.list" />
+      <recent name="D:\WorkDir\Repository\GitHub\cwiki-us-docs\java-tutorials\core-java-modules\core-java-collections-list\src\test\resources" />
+      <recent name="D:\WorkDir\Repository\GitHub\cwiki-us-docs\java-tutorials\core-java-modules\core-java-collections-list\src\test" />
     </key>
   </component>
-  <component name="RunManager" selected="JUnit.AddElementsUnitTest.givenAList_whenTargetListIsEmpty_thenReturnTargetListWithNewItems">
-    <configuration name="AddElementsUnitTest.givenAList_whenTargetListIsEmpty_thenReturnTargetListWithNewItems" type="JUnit" factoryName="JUnit" temporary="true" nameIsGenerated="true">
+  <component name="RunManager" selected="JUnit.JavaCollectionCleanupUnitTest.givenListContainsNulls_whenRemovingNullsWithGuavaV1_thenCorrect">
+    <configuration default="true" type="GoApplicationRunConfiguration" factoryName="Go Application">
+      <module name="parent-modules" />
+      <working_directory value="$PROJECT_DIR$" />
+      <go_parameters value="-i" />
+      <kind value="FILE" />
+      <directory value="$PROJECT_DIR$" />
+      <filePath value="$PROJECT_DIR$" />
+      <method v="2" />
+    </configuration>
+    <configuration default="true" type="GoTestRunConfiguration" factoryName="Go Test">
+      <module name="parent-modules" />
+      <working_directory value="$PROJECT_DIR$" />
+      <go_parameters value="-i" />
+      <kind value="DIRECTORY" />
+      <directory value="$PROJECT_DIR$" />
+      <filePath value="$PROJECT_DIR$" />
+      <framework value="gotest" />
+      <method v="2" />
+    </configuration>
+    <configuration name="JavaCollectionCleanupUnitTest.givenListContainsNulls_whenRemovingNullsWithGuavaV1_thenCorrect" type="JUnit" factoryName="JUnit" temporary="true" nameIsGenerated="true">
       <module name="core-java-collections-list" />
       <extension name="coverage">
         <pattern>
-          <option name="PATTERN" value="com.baeldung.list.*" />
+          <option name="PATTERN" value="com.ossez.collections.*" />
           <option name="ENABLED" value="true" />
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+        </line-breakpoint>
+        <line-breakpoint enabled="true" type="java-line">
+          <url>file://$PROJECT_DIR$/core-java-modules/core-java-collections-list/src/test/java/com/ossez/collections/JavaCollectionCleanupUnitTest.java</url>
+          <line>54</line>
+          <option name="timeStamp" value="4" />
         </line-breakpoint>
       </breakpoints>
     </breakpoint-manager>
diff --git a/jackson-modules/pom.xml b/jackson-modules/pom.xml
index 782bc7e81c..69ac41998d 100644
--- a/jackson-modules/pom.xml
+++ b/jackson-modules/pom.xml
@@ -39,7 +39,7 @@
             <groupId>org.junit.jupiter</groupId>
             <artifactId>junit-jupiter</artifactId>
             <version>${junit-jupiter.version}</version>
-            <scope>test</scope>
+
         </dependency>
         <dependency>
             <groupId>org.junit.vintage</groupId>
diff --git a/pom.xml b/pom.xml
index 810bc0ac96..60daf6fa35 100644
--- a/pom.xml
+++ b/pom.xml
@@ -40,12 +40,12 @@
 
     <modules>
         <module>core-java-modules</module>
-        <module>jackson-modules</module>
-        <module>jackson-simple</module>
-        <module>parent-java</module>
-        <module>testing-modules</module>
+<!--        <module>jackson-modules</module>-->
+<!--        <module>jackson-simple</module>-->
+<!--        <module>parent-java</module>-->
+<!--        <module>testing-modules</module>-->
         <module>toolkits</module>
-        <module>xml</module>
+<!--        <module>xml</module>-->
     </modules>
 
     <properties>
@@ -105,7 +105,7 @@
         <jmh-core.version>1.33</jmh-core.version>
         <exec-maven-plugin.version>3.0.0</exec-maven-plugin.version>
         <maven-surefire-plugin.version>2.21.0</maven-surefire-plugin.version>
-        <maven-compiler-plugin.version>3.8.1</maven-compiler-plugin.version>
+        <maven-compiler-plugin.version>3.10.1</maven-compiler-plugin.version>
         <logback-classic.version>1.2.5</logback-classic.version>
         <rest-assured.version>3.1.1</rest-assured.version>
 
@@ -255,7 +255,6 @@
             <artifactId>zip4j</artifactId>
             <version>1.3.2</version>
         </dependency>
-
         <!-- RETS -->
 
         <!-- TESTS -->
diff --git a/src/test/java/com/ossez/codebank/algorithm/tests/VariableTest.java b/src/test/java/com/ossez/codebank/algorithm/tests/VariableTest.java
index 844680237d..56630c8838 100644
--- a/src/test/java/com/ossez/codebank/algorithm/tests/VariableTest.java
+++ b/src/test/java/com/ossez/codebank/algorithm/tests/VariableTest.java
@@ -28,75 +28,4 @@ class OssezVariable {
     }
 }
 
-/**
- * @author YuCheng
- */
-public class VariableTest extends TestCase {
 
-    private final static Logger logger = LoggerFactory.getLogger(VariableTest.class);
-
-    /**
-     * Do RetsServerConnection Test
-     */
-    @Test
-    public void testStaticVariableChange() {
-
-//		OssezVariable objA = new OssezVariable(1, 2, 3);
-//		logger.debug("s1/s2/s3 - [{}]/[{}]/[{}]", objA.s1, objA.s2, OssezVariable.s3);
-//
-//		OssezVariable objB = new OssezVariable(4, 5, 6);
-//		logger.debug("s1/s2/s3 - [{}]/[{}]/[{}]", objA.s1, objA.s2, OssezVariable.s3);
-//		logger.debug("s1/s2/s3 - [{}]/[{}]/[{}]", objB.s1, objB.s2, OssezVariable.s3);
-
-        String[][] connections = {{"192.167.0.0", "192.167.0.1"}, {"192.167.0.2", "192.167.0.0"}, {"192.167.0.0", "192.167.0.3"}};
-        Boolean[][] connectionsP = {{false, false}, {false, false}, {false, false}};
-        String[] toggleIps = {"192.167.0.1", "192.167.0.0", "192.167.0.2", "192.167.0.0", "0.0.0.0"};
-        HashMap<String, String> ipMap = new HashMap();
-        HashMap<String, Boolean> devMap = new HashMap();
-        Integer retArray[] = new Integer[toggleIps.length];
-
-
-        for (int i = 0; i < toggleIps.length; i++) {
-            String toggleIp = toggleIps[i];
-            int count = 0;
-
-            // INIT
-            Boolean dStatus = false;
-            for (int row = 0; row < connections.length; row++) {
-                for (int col = 0; col < connections[row].length; col++) {
-
-                    String ipKey = connections[row][col];
-                    if (ipKey.equals(toggleIp))
-                        if (connectionsP[row][col] == false) {
-                            connectionsP[row][col] = true;
-                            dStatus = true;
-                        }
-                        else if (connectionsP[row][col] == true) {
-                            connectionsP[row][col] = false;
-                            dStatus = false;
-                        }
-                }
-            }
-
-            String retStr = "";
-            for (int row = 0; row < connectionsP.length; row++) {
-                List<Boolean> statusList = new ArrayList<>();
-                for (int col = 0; col < connectionsP[row].length; col++) {
-                    statusList.add(connectionsP[row][col]);
-                }
-
-                if (statusList.get(0) &&  statusList.get(1) && dStatus) {
-                    count ++;
-                }
-            }
-
-            System.out.println(count);
-
-
-        }
-
-
-//
-    }
-
-}
diff --git a/testing-modules/junit-5-basics/pom.xml b/testing-modules/junit-5-basics/pom.xml
index d905d55df1..bb10b369dd 100644
--- a/testing-modules/junit-5-basics/pom.xml
+++ b/testing-modules/junit-5-basics/pom.xml
@@ -10,9 +10,9 @@
 
     <parent>
         <groupId>com.ossez</groupId>
-        <artifactId>testing</artifactId>
+        <artifactId>testing-modules</artifactId>
         <version>0.0.2-SNAPSHOT</version>
-        <relativePath>../</relativePath>
+        <relativePath>../pom.xml</relativePath>
     </parent>
 
     <dependencies>
diff --git a/toolkits/codebank/pom.xml b/toolkits/codebank/pom.xml
index 51e2342e48..7ebf631467 100644
--- a/toolkits/codebank/pom.xml
+++ b/toolkits/codebank/pom.xml
@@ -38,6 +38,12 @@
             <artifactId>javax.persistence-api</artifactId>
             <version>2.2</version>
         </dependency>
+        <dependency>
+            <groupId>org.junit.jupiter</groupId>
+            <artifactId>junit-jupiter</artifactId>
+            <version>RELEASE</version>
+            <scope>test</scope>
+        </dependency>
     </dependencies>
 
     <build>