init backend project.

.gitignore

@@ -0,0 +1,33 @@
+HELP.md
+target/
+!.mvn/wrapper/maven-wrapper.jar
+!**/src/main/**/target/
+!**/src/test/**/target/
+
+### STS ###
+.apt_generated
+.classpath
+.factorypath
+.project
+.settings
+.springBeans
+.sts4-cache
+
+### IntelliJ IDEA ###
+.idea
+*.iws
+*.iml
+*.ipr
+
+### NetBeans ###
+/nbproject/private/
+/nbbuild/
+/dist/
+/nbdist/
+/.nb-gradle/
+build/
+!**/src/main/**/build/
+!**/src/test/**/build/
+
+### VS Code ###
+.vscode/

.idea/codeStyles

@@ -0,0 +1,31 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="ProjectCodeStyleConfiguration">
+    <code_scheme name="Project" version="173">
+      <DBN-PSQL>
+        <case-options enabled="true">
+          <option name="KEYWORD_CASE" value="lower" />
+          <option name="FUNCTION_CASE" value="lower" />
+          <option name="PARAMETER_CASE" value="lower" />
+          <option name="DATATYPE_CASE" value="lower" />
+          <option name="OBJECT_CASE" value="preserve" />
+        </case-options>
+        <formatting-settings enabled="false" />
+      </DBN-PSQL>
+      <DBN-SQL>
+        <case-options enabled="true">
+          <option name="KEYWORD_CASE" value="lower" />
+          <option name="FUNCTION_CASE" value="lower" />
+          <option name="PARAMETER_CASE" value="lower" />
+          <option name="DATATYPE_CASE" value="lower" />
+          <option name="OBJECT_CASE" value="preserve" />
+        </case-options>
+        <formatting-settings enabled="false">
+          <option name="STATEMENT_SPACING" value="one_line" />
+          <option name="CLAUSE_CHOP_DOWN" value="chop_down_if_statement_long" />
+          <option name="ITERATION_ELEMENTS_WRAPPING" value="chop_down_if_not_single" />
+        </formatting-settings>
+      </DBN-SQL>
+    </code_scheme>
+  </component>
+</project>

.idea/compiler.xml

@@ -0,0 +1,21 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="CompilerConfiguration">
+    <annotationProcessing>
+      <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="data-structure-service" />
+      </profile>
+    </annotationProcessing>
+    <bytecodeTargetLevel>
+      <module name="data-structure-service" target="1.8" />
+    </bytecodeTargetLevel>
+  </component>
+  <component name="JavacSettings">
+    <option name="ADDITIONAL_OPTIONS_OVERRIDE">
+      <module name="data-structure-service" options="-parameters" />
+    </option>
+  </component>
+</project>

.idea/dbnavigator.xml

@@ -0,0 +1,456 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="DBNavigator.Project.DataEditorManager">
+    <record-view-column-sorting-type value="BY_INDEX" />
+    <value-preview-text-wrapping value="true" />
+    <value-preview-pinned value="false" />
+  </component>
+  <component name="DBNavigator.Project.DataExportManager">
+    <export-instructions>
+      <create-header value="true" />
+      <quote-values-containing-separator value="true" />
+      <quote-all-values value="false" />
+      <value-separator value="" />
+      <file-name value="" />
+      <file-location value="" />
+      <scope value="GLOBAL" />
+      <destination value="FILE" />
+      <format value="EXCEL" />
+      <charset value="GBK" />
+    </export-instructions>
+  </component>
+  <component name="DBNavigator.Project.DatabaseBrowserManager">
+    <autoscroll-to-editor value="false" />
+    <autoscroll-from-editor value="true" />
+    <show-object-properties value="true" />
+    <loaded-nodes />
+  </component>
+  <component name="DBNavigator.Project.DatabaseFileManager">
+    <open-files />
+  </component>
+  <component name="DBNavigator.Project.EditorStateManager">
+    <last-used-providers />
+  </component>
+  <component name="DBNavigator.Project.MethodExecutionManager">
+    <method-browser />
+    <execution-history>
+      <group-entries value="true" />
+      <execution-inputs />
+    </execution-history>
+    <argument-values-cache />
+  </component>
+  <component name="DBNavigator.Project.ObjectDependencyManager">
+    <last-used-dependency-type value="INCOMING" />
+  </component>
+  <component name="DBNavigator.Project.ObjectQuickFilterManager">
+    <last-used-operator value="EQUAL" />
+    <filters />
+  </component>
+  <component name="DBNavigator.Project.ScriptExecutionManager" clear-outputs="true">
+    <recently-used-interfaces />
+  </component>
+  <component name="DBNavigator.Project.Settings">
+    <connections />
+    <browser-settings>
+      <general>
+        <display-mode value="TABBED" />
+        <navigation-history-size value="100" />
+        <show-object-details value="false" />
+      </general>
+      <filters>
+        <object-type-filter>
+          <object-type name="SCHEMA" enabled="true" />
+          <object-type name="USER" enabled="true" />
+          <object-type name="ROLE" enabled="true" />
+          <object-type name="PRIVILEGE" enabled="true" />
+          <object-type name="CHARSET" enabled="true" />
+          <object-type name="TABLE" enabled="true" />
+          <object-type name="VIEW" enabled="true" />
+          <object-type name="MATERIALIZED_VIEW" enabled="true" />
+          <object-type name="NESTED_TABLE" enabled="true" />
+          <object-type name="COLUMN" enabled="true" />
+          <object-type name="INDEX" enabled="true" />
+          <object-type name="CONSTRAINT" enabled="true" />
+          <object-type name="DATASET_TRIGGER" enabled="true" />
+          <object-type name="DATABASE_TRIGGER" enabled="true" />
+          <object-type name="SYNONYM" enabled="true" />
+          <object-type name="SEQUENCE" enabled="true" />
+          <object-type name="PROCEDURE" enabled="true" />
+          <object-type name="FUNCTION" enabled="true" />
+          <object-type name="PACKAGE" enabled="true" />
+          <object-type name="TYPE" enabled="true" />
+          <object-type name="TYPE_ATTRIBUTE" enabled="true" />
+          <object-type name="ARGUMENT" enabled="true" />
+          <object-type name="DIMENSION" enabled="true" />
+          <object-type name="CLUSTER" enabled="true" />
+          <object-type name="DBLINK" enabled="true" />
+        </object-type-filter>
+      </filters>
+      <sorting>
+        <object-type name="COLUMN" sorting-type="NAME" />
+        <object-type name="FUNCTION" sorting-type="NAME" />
+        <object-type name="PROCEDURE" sorting-type="NAME" />
+        <object-type name="ARGUMENT" sorting-type="POSITION" />
+      </sorting>
+      <default-editors>
+        <object-type name="VIEW" editor-type="SELECTION" />
+        <object-type name="PACKAGE" editor-type="SELECTION" />
+        <object-type name="TYPE" editor-type="SELECTION" />
+      </default-editors>
+    </browser-settings>
+    <navigation-settings>
+      <lookup-filters>
+        <lookup-objects>
+          <object-type name="SCHEMA" enabled="true" />
+          <object-type name="USER" enabled="false" />
+          <object-type name="ROLE" enabled="false" />
+          <object-type name="PRIVILEGE" enabled="false" />
+          <object-type name="CHARSET" enabled="false" />
+          <object-type name="TABLE" enabled="true" />
+          <object-type name="VIEW" enabled="true" />
+          <object-type name="MATERIALIZED VIEW" enabled="true" />
+          <object-type name="NESTED TABLE" enabled="false" />
+          <object-type name="COLUMN" enabled="false" />
+          <object-type name="INDEX" enabled="true" />
+          <object-type name="CONSTRAINT" enabled="true" />
+          <object-type name="DATASET TRIGGER" enabled="true" />
+          <object-type name="DATABASE TRIGGER" enabled="true" />
+          <object-type name="SYNONYM" enabled="false" />
+          <object-type name="SEQUENCE" enabled="true" />
+          <object-type name="PROCEDURE" enabled="true" />
+          <object-type name="FUNCTION" enabled="true" />
+          <object-type name="PACKAGE" enabled="true" />
+          <object-type name="TYPE" enabled="true" />
+          <object-type name="TYPE ATTRIBUTE" enabled="false" />
+          <object-type name="ARGUMENT" enabled="false" />
+          <object-type name="DIMENSION" enabled="false" />
+          <object-type name="CLUSTER" enabled="false" />
+          <object-type name="DBLINK" enabled="true" />
+        </lookup-objects>
+        <force-database-load value="false" />
+        <prompt-connection-selection value="true" />
+        <prompt-schema-selection value="true" />
+      </lookup-filters>
+    </navigation-settings>
+    <dataset-grid-settings>
+      <general>
+        <enable-zooming value="true" />
+        <enable-column-tooltip value="true" />
+      </general>
+      <sorting>
+        <nulls-first value="true" />
+        <max-sorting-columns value="4" />
+      </sorting>
+      <tracking-columns>
+        <columnNames value="" />
+        <visible value="true" />
+        <editable value="false" />
+      </tracking-columns>
+    </dataset-grid-settings>
+    <dataset-editor-settings>
+      <text-editor-popup>
+        <active value="false" />
+        <active-if-empty value="false" />
+        <data-length-threshold value="100" />
+        <popup-delay value="1000" />
+      </text-editor-popup>
+      <values-actions-popup>
+        <show-popup-button value="true" />
+        <element-count-threshold value="1000" />
+        <data-length-threshold value="250" />
+      </values-actions-popup>
+      <general>
+        <fetch-block-size value="100" />
+        <fetch-timeout value="30" />
+        <trim-whitespaces value="true" />
+        <convert-empty-strings-to-null value="true" />
+        <select-content-on-cell-edit value="true" />
+        <large-value-preview-active value="true" />
+      </general>
+      <filters>
+        <prompt-filter-dialog value="true" />
+        <default-filter-type value="BASIC" />
+      </filters>
+      <qualified-text-editor text-length-threshold="300">
+        <content-types>
+          <content-type name="Text" enabled="true" />
+          <content-type name="Properties" enabled="true" />
+          <content-type name="XML" enabled="true" />
+          <content-type name="DTD" enabled="true" />
+          <content-type name="HTML" enabled="true" />
+          <content-type name="XHTML" enabled="true" />
+          <content-type name="Java" enabled="true" />
+          <content-type name="SQL" enabled="true" />
+          <content-type name="PL/SQL" enabled="true" />
+          <content-type name="Groovy" enabled="true" />
+          <content-type name="AIDL" enabled="true" />
+          <content-type name="YAML" enabled="true" />
+          <content-type name="Manifest" enabled="true" />
+        </content-types>
+      </qualified-text-editor>
+      <record-navigation>
+        <navigation-target value="VIEWER" />
+      </record-navigation>
+    </dataset-editor-settings>
+    <code-editor-settings>
+      <general>
+        <show-object-navigation-gutter value="false" />
+        <show-spec-declaration-navigation-gutter value="true" />
+        <enable-spellchecking value="true" />
+        <enable-reference-spellchecking value="false" />
+      </general>
+      <confirmations>
+        <save-changes value="false" />
+        <revert-changes value="true" />
+      </confirmations>
+    </code-editor-settings>
+    <code-completion-settings>
+      <filters>
+        <basic-filter>
+          <filter-element type="RESERVED_WORD" id="keyword" selected="true" />
+          <filter-element type="RESERVED_WORD" id="function" selected="true" />
+          <filter-element type="RESERVED_WORD" id="parameter" selected="true" />
+          <filter-element type="RESERVED_WORD" id="datatype" selected="true" />
+          <filter-element type="RESERVED_WORD" id="exception" selected="true" />
+          <filter-element type="OBJECT" id="schema" selected="true" />
+          <filter-element type="OBJECT" id="role" selected="true" />
+          <filter-element type="OBJECT" id="user" selected="true" />
+          <filter-element type="OBJECT" id="privilege" selected="true" />
+          <user-schema>
+            <filter-element type="OBJECT" id="table" selected="true" />
+            <filter-element type="OBJECT" id="view" selected="true" />
+            <filter-element type="OBJECT" id="materialized view" selected="true" />
+            <filter-element type="OBJECT" id="index" selected="true" />
+            <filter-element type="OBJECT" id="constraint" selected="true" />
+            <filter-element type="OBJECT" id="trigger" selected="true" />
+            <filter-element type="OBJECT" id="synonym" selected="false" />
+            <filter-element type="OBJECT" id="sequence" selected="true" />
+            <filter-element type="OBJECT" id="procedure" selected="true" />
+            <filter-element type="OBJECT" id="function" selected="true" />
+            <filter-element type="OBJECT" id="package" selected="true" />
+            <filter-element type="OBJECT" id="type" selected="true" />
+            <filter-element type="OBJECT" id="dimension" selected="true" />
+            <filter-element type="OBJECT" id="cluster" selected="true" />
+            <filter-element type="OBJECT" id="dblink" selected="true" />
+          </user-schema>
+          <public-schema>
+            <filter-element type="OBJECT" id="table" selected="false" />
+            <filter-element type="OBJECT" id="view" selected="false" />
+            <filter-element type="OBJECT" id="materialized view" selected="false" />
+            <filter-element type="OBJECT" id="index" selected="false" />
+            <filter-element type="OBJECT" id="constraint" selected="false" />
+            <filter-element type="OBJECT" id="trigger" selected="false" />
+            <filter-element type="OBJECT" id="synonym" selected="false" />
+            <filter-element type="OBJECT" id="sequence" selected="false" />
+            <filter-element type="OBJECT" id="procedure" selected="false" />
+            <filter-element type="OBJECT" id="function" selected="false" />
+            <filter-element type="OBJECT" id="package" selected="false" />
+            <filter-element type="OBJECT" id="type" selected="false" />
+            <filter-element type="OBJECT" id="dimension" selected="false" />
+            <filter-element type="OBJECT" id="cluster" selected="false" />
+            <filter-element type="OBJECT" id="dblink" selected="false" />
+          </public-schema>
+          <any-schema>
+            <filter-element type="OBJECT" id="table" selected="true" />
+            <filter-element type="OBJECT" id="view" selected="true" />
+            <filter-element type="OBJECT" id="materialized view" selected="true" />
+            <filter-element type="OBJECT" id="index" selected="true" />
+            <filter-element type="OBJECT" id="constraint" selected="true" />
+            <filter-element type="OBJECT" id="trigger" selected="true" />
+            <filter-element type="OBJECT" id="synonym" selected="true" />
+            <filter-element type="OBJECT" id="sequence" selected="true" />
+            <filter-element type="OBJECT" id="procedure" selected="true" />
+            <filter-element type="OBJECT" id="function" selected="true" />
+            <filter-element type="OBJECT" id="package" selected="true" />
+            <filter-element type="OBJECT" id="type" selected="true" />
+            <filter-element type="OBJECT" id="dimension" selected="true" />
+            <filter-element type="OBJECT" id="cluster" selected="true" />
+            <filter-element type="OBJECT" id="dblink" selected="true" />
+          </any-schema>
+        </basic-filter>
+        <extended-filter>
+          <filter-element type="RESERVED_WORD" id="keyword" selected="true" />
+          <filter-element type="RESERVED_WORD" id="function" selected="true" />
+          <filter-element type="RESERVED_WORD" id="parameter" selected="true" />
+          <filter-element type="RESERVED_WORD" id="datatype" selected="true" />
+          <filter-element type="RESERVED_WORD" id="exception" selected="true" />
+          <filter-element type="OBJECT" id="schema" selected="true" />
+          <filter-element type="OBJECT" id="user" selected="true" />
+          <filter-element type="OBJECT" id="role" selected="true" />
+          <filter-element type="OBJECT" id="privilege" selected="true" />
+          <user-schema>
+            <filter-element type="OBJECT" id="table" selected="true" />
+            <filter-element type="OBJECT" id="view" selected="true" />
+            <filter-element type="OBJECT" id="materialized view" selected="true" />
+            <filter-element type="OBJECT" id="index" selected="true" />
+            <filter-element type="OBJECT" id="constraint" selected="true" />
+            <filter-element type="OBJECT" id="trigger" selected="true" />
+            <filter-element type="OBJECT" id="synonym" selected="true" />
+            <filter-element type="OBJECT" id="sequence" selected="true" />
+            <filter-element type="OBJECT" id="procedure" selected="true" />
+            <filter-element type="OBJECT" id="function" selected="true" />
+            <filter-element type="OBJECT" id="package" selected="true" />
+            <filter-element type="OBJECT" id="type" selected="true" />
+            <filter-element type="OBJECT" id="dimension" selected="true" />
+            <filter-element type="OBJECT" id="cluster" selected="true" />
+            <filter-element type="OBJECT" id="dblink" selected="true" />
+          </user-schema>
+          <public-schema>
+            <filter-element type="OBJECT" id="table" selected="true" />
+            <filter-element type="OBJECT" id="view" selected="true" />
+            <filter-element type="OBJECT" id="materialized view" selected="true" />
+            <filter-element type="OBJECT" id="index" selected="true" />
+            <filter-element type="OBJECT" id="constraint" selected="true" />
+            <filter-element type="OBJECT" id="trigger" selected="true" />
+            <filter-element type="OBJECT" id="synonym" selected="true" />
+            <filter-element type="OBJECT" id="sequence" selected="true" />
+            <filter-element type="OBJECT" id="procedure" selected="true" />
+            <filter-element type="OBJECT" id="function" selected="true" />
+            <filter-element type="OBJECT" id="package" selected="true" />
+            <filter-element type="OBJECT" id="type" selected="true" />
+            <filter-element type="OBJECT" id="dimension" selected="true" />
+            <filter-element type="OBJECT" id="cluster" selected="true" />
+            <filter-element type="OBJECT" id="dblink" selected="true" />
+          </public-schema>
+          <any-schema>
+            <filter-element type="OBJECT" id="table" selected="true" />
+            <filter-element type="OBJECT" id="view" selected="true" />
+            <filter-element type="OBJECT" id="materialized view" selected="true" />
+            <filter-element type="OBJECT" id="index" selected="true" />
+            <filter-element type="OBJECT" id="constraint" selected="true" />
+            <filter-element type="OBJECT" id="trigger" selected="true" />
+            <filter-element type="OBJECT" id="synonym" selected="true" />
+            <filter-element type="OBJECT" id="sequence" selected="true" />
+            <filter-element type="OBJECT" id="procedure" selected="true" />
+            <filter-element type="OBJECT" id="function" selected="true" />
+            <filter-element type="OBJECT" id="package" selected="true" />
+            <filter-element type="OBJECT" id="type" selected="true" />
+            <filter-element type="OBJECT" id="dimension" selected="true" />
+            <filter-element type="OBJECT" id="cluster" selected="true" />
+            <filter-element type="OBJECT" id="dblink" selected="true" />
+          </any-schema>
+        </extended-filter>
+      </filters>
+      <sorting enabled="true">
+        <sorting-element type="RESERVED_WORD" id="keyword" />
+        <sorting-element type="RESERVED_WORD" id="datatype" />
+        <sorting-element type="OBJECT" id="column" />
+        <sorting-element type="OBJECT" id="table" />
+        <sorting-element type="OBJECT" id="view" />
+        <sorting-element type="OBJECT" id="materialized view" />
+        <sorting-element type="OBJECT" id="index" />
+        <sorting-element type="OBJECT" id="constraint" />
+        <sorting-element type="OBJECT" id="trigger" />
+        <sorting-element type="OBJECT" id="synonym" />
+        <sorting-element type="OBJECT" id="sequence" />
+        <sorting-element type="OBJECT" id="procedure" />
+        <sorting-element type="OBJECT" id="function" />
+        <sorting-element type="OBJECT" id="package" />
+        <sorting-element type="OBJECT" id="type" />
+        <sorting-element type="OBJECT" id="dimension" />
+        <sorting-element type="OBJECT" id="cluster" />
+        <sorting-element type="OBJECT" id="dblink" />
+        <sorting-element type="OBJECT" id="schema" />
+        <sorting-element type="OBJECT" id="role" />
+        <sorting-element type="OBJECT" id="user" />
+        <sorting-element type="RESERVED_WORD" id="function" />
+        <sorting-element type="RESERVED_WORD" id="parameter" />
+      </sorting>
+      <format>
+        <enforce-code-style-case value="true" />
+      </format>
+    </code-completion-settings>
+    <execution-engine-settings>
+      <statement-execution>
+        <fetch-block-size value="100" />
+        <execution-timeout value="20" />
+        <debug-execution-timeout value="600" />
+        <focus-result value="false" />
+        <prompt-execution value="false" />
+      </statement-execution>
+      <script-execution>
+        <command-line-interfaces />
+        <execution-timeout value="300" />
+      </script-execution>
+      <method-execution>
+        <execution-timeout value="30" />
+        <debug-execution-timeout value="600" />
+        <parameter-history-size value="10" />
+      </method-execution>
+    </execution-engine-settings>
+    <operation-settings>
+      <transactions>
+        <uncommitted-changes>
+          <on-project-close value="ASK" />
+          <on-disconnect value="ASK" />
+          <on-autocommit-toggle value="ASK" />
+        </uncommitted-changes>
+        <multiple-uncommitted-changes>
+          <on-commit value="ASK" />
+          <on-rollback value="ASK" />
+        </multiple-uncommitted-changes>
+      </transactions>
+      <session-browser>
+        <disconnect-session value="ASK" />
+        <kill-session value="ASK" />
+        <reload-on-filter-change value="false" />
+      </session-browser>
+      <compiler>
+        <compile-type value="KEEP" />
+        <compile-dependencies value="ASK" />
+        <always-show-controls value="false" />
+      </compiler>
+      <debugger>
+        <debugger-type value="ASK" />
+        <use-generic-runners value="true" />
+      </debugger>
+    </operation-settings>
+    <ddl-file-settings>
+      <extensions>
+        <mapping file-type-id="VIEW" extensions="vw" />
+        <mapping file-type-id="TRIGGER" extensions="trg" />
+        <mapping file-type-id="PROCEDURE" extensions="prc" />
+        <mapping file-type-id="FUNCTION" extensions="fnc" />
+        <mapping file-type-id="PACKAGE" extensions="pkg" />
+        <mapping file-type-id="PACKAGE_SPEC" extensions="pks" />
+        <mapping file-type-id="PACKAGE_BODY" extensions="pkb" />
+        <mapping file-type-id="TYPE" extensions="tpe" />
+        <mapping file-type-id="TYPE_SPEC" extensions="tps" />
+        <mapping file-type-id="TYPE_BODY" extensions="tpb" />
+      </extensions>
+      <general>
+        <lookup-ddl-files value="true" />
+        <create-ddl-files value="false" />
+        <synchronize-ddl-files value="true" />
+        <use-qualified-names value="false" />
+        <make-scripts-rerunnable value="true" />
+      </general>
+    </ddl-file-settings>
+    <general-settings>
+      <regional-settings>
+        <date-format value="MEDIUM" />
+        <number-format value="UNGROUPED" />
+        <locale value="SYSTEM_DEFAULT" />
+        <use-custom-formats value="false" />
+      </regional-settings>
+      <environment>
+        <environment-types>
+          <environment-type id="development" name="Development" description="Development environment" color="-2430209/-12296320" readonly-code="false" readonly-data="false" />
+          <environment-type id="integration" name="Integration" description="Integration environment" color="-2621494/-12163514" readonly-code="true" readonly-data="false" />
+          <environment-type id="production" name="Production" description="Productive environment" color="-11574/-10271420" readonly-code="true" readonly-data="true" />
+          <environment-type id="other" name="Other" description="" color="-1576/-10724543" readonly-code="false" readonly-data="false" />
+        </environment-types>
+        <visibility-settings>
+          <connection-tabs value="true" />
+          <dialog-headers value="true" />
+          <object-editor-tabs value="true" />
+          <script-editor-tabs value="false" />
+          <execution-result-tabs value="true" />
+        </visibility-settings>
+      </environment>
+    </general-settings>
+  </component>
+  <component name="DBNavigator.Project.StatementExecutionManager">
+    <execution-variables />
+  </component>
+</project>

.idea/misc.xml

@@ -0,0 +1,13 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="MavenProjectsManager">
+    <option name="originalFiles">
+      <list>
+        <option value="$PROJECT_DIR$/pom.xml" />
+      </list>
+    </option>
+  </component>
+  <component name="ProjectRootManager" version="2" languageLevel="JDK_1_8" project-jdk-name="1.8" project-jdk-type="JavaSDK">
+    <output url="file://$PROJECT_DIR$/out" />
+  </component>
+</project>

.idea/vcs.xml

@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="VcsDirectoryMappings">
+    <mapping directory="" vcs="Git" />
+  </component>
+</project>

.mvn/wrapper/MavenWrapperDownloader.java

@@ -0,0 +1,117 @@
+/*
+ * Copyright 2007-present the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+import java.net.*;
+import java.io.*;
+import java.nio.channels.*;
+import java.util.Properties;
+
+public class MavenWrapperDownloader {
+
+    private static final String WRAPPER_VERSION = "0.5.6";
+    /**
+     * Default URL to download the maven-wrapper.jar from, if no 'downloadUrl' is provided.
+     */
+    private static final String DEFAULT_DOWNLOAD_URL = "https://repo.maven.apache.org/maven2/io/takari/maven-wrapper/"
+        + WRAPPER_VERSION + "/maven-wrapper-" + WRAPPER_VERSION + ".jar";
+
+    /**
+     * Path to the maven-wrapper.properties file, which might contain a downloadUrl property to
+     * use instead of the default one.
+     */
+    private static final String MAVEN_WRAPPER_PROPERTIES_PATH =
+            ".mvn/wrapper/maven-wrapper.properties";
+
+    /**
+     * Path where the maven-wrapper.jar will be saved to.
+     */
+    private static final String MAVEN_WRAPPER_JAR_PATH =
+            ".mvn/wrapper/maven-wrapper.jar";
+
+    /**
+     * Name of the property which should be used to override the default download url for the wrapper.
+     */
+    private static final String PROPERTY_NAME_WRAPPER_URL = "wrapperUrl";
+
+    public static void main(String args[]) {
+        System.out.println("- Downloader started");
+        File baseDirectory = new File(args[0]);
+        System.out.println("- Using base directory: " + baseDirectory.getAbsolutePath());
+
+        // If the maven-wrapper.properties exists, read it and check if it contains a custom
+        // wrapperUrl parameter.
+        File mavenWrapperPropertyFile = new File(baseDirectory, MAVEN_WRAPPER_PROPERTIES_PATH);
+        String url = DEFAULT_DOWNLOAD_URL;
+        if(mavenWrapperPropertyFile.exists()) {
+            FileInputStream mavenWrapperPropertyFileInputStream = null;
+            try {
+                mavenWrapperPropertyFileInputStream = new FileInputStream(mavenWrapperPropertyFile);
+                Properties mavenWrapperProperties = new Properties();
+                mavenWrapperProperties.load(mavenWrapperPropertyFileInputStream);
+                url = mavenWrapperProperties.getProperty(PROPERTY_NAME_WRAPPER_URL, url);
+            } catch (IOException e) {
+                System.out.println("- ERROR loading '" + MAVEN_WRAPPER_PROPERTIES_PATH + "'");
+            } finally {
+                try {
+                    if(mavenWrapperPropertyFileInputStream != null) {
+                        mavenWrapperPropertyFileInputStream.close();
+                    }
+                } catch (IOException e) {
+                    // Ignore ...
+                }
+            }
+        }
+        System.out.println("- Downloading from: " + url);
+
+        File outputFile = new File(baseDirectory.getAbsolutePath(), MAVEN_WRAPPER_JAR_PATH);
+        if(!outputFile.getParentFile().exists()) {
+            if(!outputFile.getParentFile().mkdirs()) {
+                System.out.println(
+                        "- ERROR creating output directory '" + outputFile.getParentFile().getAbsolutePath() + "'");
+            }
+        }
+        System.out.println("- Downloading to: " + outputFile.getAbsolutePath());
+        try {
+            downloadFileFromURL(url, outputFile);
+            System.out.println("Done");
+            System.exit(0);
+        } catch (Throwable e) {
+            System.out.println("- Error downloading");
+            e.printStackTrace();
+            System.exit(1);
+        }
+    }
+
+    private static void downloadFileFromURL(String urlString, File destination) throws Exception {
+        if (System.getenv("MVNW_USERNAME") != null && System.getenv("MVNW_PASSWORD") != null) {
+            String username = System.getenv("MVNW_USERNAME");
+            char[] password = System.getenv("MVNW_PASSWORD").toCharArray();
+            Authenticator.setDefault(new Authenticator() {
+                @Override
+                protected PasswordAuthentication getPasswordAuthentication() {
+                    return new PasswordAuthentication(username, password);
+                }
+            });
+        }
+        URL website = new URL(urlString);
+        ReadableByteChannel rbc;
+        rbc = Channels.newChannel(website.openStream());
+        FileOutputStream fos = new FileOutputStream(destination);
+        fos.getChannel().transferFrom(rbc, 0, Long.MAX_VALUE);
+        fos.close();
+        rbc.close();
+    }
+
+}

.mvn/wrapper/maven-wrapper.properties

@@ -0,0 +1,2 @@
+distributionUrl=https://repo.maven.apache.org/maven2/org/apache/maven/apache-maven/3.8.1/apache-maven-3.8.1-bin.zip
+wrapperUrl=https://repo.maven.apache.org/maven2/io/takari/maven-wrapper/0.5.6/maven-wrapper-0.5.6.jar

mvnw

@@ -0,0 +1,310 @@
+#!/bin/sh
+# ----------------------------------------------------------------------------
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#    https://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+# ----------------------------------------------------------------------------
+
+# ----------------------------------------------------------------------------
+# Maven Start Up Batch script
+#
+# Required ENV vars:
+# ------------------
+#   JAVA_HOME - location of a JDK home dir
+#
+# Optional ENV vars
+# -----------------
+#   M2_HOME - location of maven2's installed home dir
+#   MAVEN_OPTS - parameters passed to the Java VM when running Maven
+#     e.g. to debug Maven itself, use
+#       set MAVEN_OPTS=-Xdebug -Xrunjdwp:transport=dt_socket,server=y,suspend=y,address=8000
+#   MAVEN_SKIP_RC - flag to disable loading of mavenrc files
+# ----------------------------------------------------------------------------
+
+if [ -z "$MAVEN_SKIP_RC" ] ; then
+
+  if [ -f /etc/mavenrc ] ; then
+    . /etc/mavenrc
+  fi
+
+  if [ -f "$HOME/.mavenrc" ] ; then
+    . "$HOME/.mavenrc"
+  fi
+
+fi
+
+# OS specific support.  $var _must_ be set to either true or false.
+cygwin=false;
+darwin=false;
+mingw=false
+case "`uname`" in
+  CYGWIN*) cygwin=true ;;
+  MINGW*) mingw=true;;
+  Darwin*) darwin=true
+    # Use /usr/libexec/java_home if available, otherwise fall back to /Library/Java/Home
+    # See https://developer.apple.com/library/mac/qa/qa1170/_index.html
+    if [ -z "$JAVA_HOME" ]; then
+      if [ -x "/usr/libexec/java_home" ]; then
+        export JAVA_HOME="`/usr/libexec/java_home`"
+      else
+        export JAVA_HOME="/Library/Java/Home"
+      fi
+    fi
+    ;;
+esac
+
+if [ -z "$JAVA_HOME" ] ; then
+  if [ -r /etc/gentoo-release ] ; then
+    JAVA_HOME=`java-config --jre-home`
+  fi
+fi
+
+if [ -z "$M2_HOME" ] ; then
+  ## resolve links - $0 may be a link to maven's home
+  PRG="$0"
+
+  # need this for relative symlinks
+  while [ -h "$PRG" ] ; do
+    ls=`ls -ld "$PRG"`
+    link=`expr "$ls" : '.*-> \(.*\)$'`
+    if expr "$link" : '/.*' > /dev/null; then
+      PRG="$link"
+    else
+      PRG="`dirname "$PRG"`/$link"
+    fi
+  done
+
+  saveddir=`pwd`
+
+  M2_HOME=`dirname "$PRG"`/..
+
+  # make it fully qualified
+  M2_HOME=`cd "$M2_HOME" && pwd`
+
+  cd "$saveddir"
+  # echo Using m2 at $M2_HOME
+fi
+
+# For Cygwin, ensure paths are in UNIX format before anything is touched
+if $cygwin ; then
+  [ -n "$M2_HOME" ] &&
+    M2_HOME=`cygpath --unix "$M2_HOME"`
+  [ -n "$JAVA_HOME" ] &&
+    JAVA_HOME=`cygpath --unix "$JAVA_HOME"`
+  [ -n "$CLASSPATH" ] &&
+    CLASSPATH=`cygpath --path --unix "$CLASSPATH"`
+fi
+
+# For Mingw, ensure paths are in UNIX format before anything is touched
+if $mingw ; then
+  [ -n "$M2_HOME" ] &&
+    M2_HOME="`(cd "$M2_HOME"; pwd)`"
+  [ -n "$JAVA_HOME" ] &&
+    JAVA_HOME="`(cd "$JAVA_HOME"; pwd)`"
+fi
+
+if [ -z "$JAVA_HOME" ]; then
+  javaExecutable="`which javac`"
+  if [ -n "$javaExecutable" ] && ! [ "`expr \"$javaExecutable\" : '\([^ ]*\)'`" = "no" ]; then
+    # readlink(1) is not available as standard on Solaris 10.
+    readLink=`which readlink`
+    if [ ! `expr "$readLink" : '\([^ ]*\)'` = "no" ]; then
+      if $darwin ; then
+        javaHome="`dirname \"$javaExecutable\"`"
+        javaExecutable="`cd \"$javaHome\" && pwd -P`/javac"
+      else
+        javaExecutable="`readlink -f \"$javaExecutable\"`"
+      fi
+      javaHome="`dirname \"$javaExecutable\"`"
+      javaHome=`expr "$javaHome" : '\(.*\)/bin'`
+      JAVA_HOME="$javaHome"
+      export JAVA_HOME
+    fi
+  fi
+fi
+
+if [ -z "$JAVACMD" ] ; then
+  if [ -n "$JAVA_HOME"  ] ; then
+    if [ -x "$JAVA_HOME/jre/sh/java" ] ; then
+      # IBM's JDK on AIX uses strange locations for the executables
+      JAVACMD="$JAVA_HOME/jre/sh/java"
+    else
+      JAVACMD="$JAVA_HOME/bin/java"
+    fi
+  else
+    JAVACMD="`which java`"
+  fi
+fi
+
+if [ ! -x "$JAVACMD" ] ; then
+  echo "Error: JAVA_HOME is not defined correctly." >&2
+  echo "  We cannot execute $JAVACMD" >&2
+  exit 1
+fi
+
+if [ -z "$JAVA_HOME" ] ; then
+  echo "Warning: JAVA_HOME environment variable is not set."
+fi
+
+CLASSWORLDS_LAUNCHER=org.codehaus.plexus.classworlds.launcher.Launcher
+
+# traverses directory structure from process work directory to filesystem root
+# first directory with .mvn subdirectory is considered project base directory
+find_maven_basedir() {
+
+  if [ -z "$1" ]
+  then
+    echo "Path not specified to find_maven_basedir"
+    return 1
+  fi
+
+  basedir="$1"
+  wdir="$1"
+  while [ "$wdir" != '/' ] ; do
+    if [ -d "$wdir"/.mvn ] ; then
+      basedir=$wdir
+      break
+    fi
+    # workaround for JBEAP-8937 (on Solaris 10/Sparc)
+    if [ -d "${wdir}" ]; then
+      wdir=`cd "$wdir/.."; pwd`
+    fi
+    # end of workaround
+  done
+  echo "${basedir}"
+}
+
+# concatenates all lines of a file
+concat_lines() {
+  if [ -f "$1" ]; then
+    echo "$(tr -s '\n' ' ' < "$1")"
+  fi
+}
+
+BASE_DIR=`find_maven_basedir "$(pwd)"`
+if [ -z "$BASE_DIR" ]; then
+  exit 1;
+fi
+
+##########################################################################################
+# Extension to allow automatically downloading the maven-wrapper.jar from Maven-central
+# This allows using the maven wrapper in projects that prohibit checking in binary data.
+##########################################################################################
+if [ -r "$BASE_DIR/.mvn/wrapper/maven-wrapper.jar" ]; then
+    if [ "$MVNW_VERBOSE" = true ]; then
+      echo "Found .mvn/wrapper/maven-wrapper.jar"
+    fi
+else
+    if [ "$MVNW_VERBOSE" = true ]; then
+      echo "Couldn't find .mvn/wrapper/maven-wrapper.jar, downloading it ..."
+    fi
+    if [ -n "$MVNW_REPOURL" ]; then
+      jarUrl="$MVNW_REPOURL/io/takari/maven-wrapper/0.5.6/maven-wrapper-0.5.6.jar"
+    else
+      jarUrl="https://repo.maven.apache.org/maven2/io/takari/maven-wrapper/0.5.6/maven-wrapper-0.5.6.jar"
+    fi
+    while IFS="=" read key value; do
+      case "$key" in (wrapperUrl) jarUrl="$value"; break ;;
+      esac
+    done < "$BASE_DIR/.mvn/wrapper/maven-wrapper.properties"
+    if [ "$MVNW_VERBOSE" = true ]; then
+      echo "Downloading from: $jarUrl"
+    fi
+    wrapperJarPath="$BASE_DIR/.mvn/wrapper/maven-wrapper.jar"
+    if $cygwin; then
+      wrapperJarPath=`cygpath --path --windows "$wrapperJarPath"`
+    fi
+
+    if command -v wget > /dev/null; then
+        if [ "$MVNW_VERBOSE" = true ]; then
+          echo "Found wget ... using wget"
+        fi
+        if [ -z "$MVNW_USERNAME" ] || [ -z "$MVNW_PASSWORD" ]; then
+            wget "$jarUrl" -O "$wrapperJarPath"
+        else
+            wget --http-user=$MVNW_USERNAME --http-password=$MVNW_PASSWORD "$jarUrl" -O "$wrapperJarPath"
+        fi
+    elif command -v curl > /dev/null; then
+        if [ "$MVNW_VERBOSE" = true ]; then
+          echo "Found curl ... using curl"
+        fi
+        if [ -z "$MVNW_USERNAME" ] || [ -z "$MVNW_PASSWORD" ]; then
+            curl -o "$wrapperJarPath" "$jarUrl" -f
+        else
+            curl --user $MVNW_USERNAME:$MVNW_PASSWORD -o "$wrapperJarPath" "$jarUrl" -f
+        fi
+
+    else
+        if [ "$MVNW_VERBOSE" = true ]; then
+          echo "Falling back to using Java to download"
+        fi
+        javaClass="$BASE_DIR/.mvn/wrapper/MavenWrapperDownloader.java"
+        # For Cygwin, switch paths to Windows format before running javac
+        if $cygwin; then
+          javaClass=`cygpath --path --windows "$javaClass"`
+        fi
+        if [ -e "$javaClass" ]; then
+            if [ ! -e "$BASE_DIR/.mvn/wrapper/MavenWrapperDownloader.class" ]; then
+                if [ "$MVNW_VERBOSE" = true ]; then
+                  echo " - Compiling MavenWrapperDownloader.java ..."
+                fi
+                # Compiling the Java class
+                ("$JAVA_HOME/bin/javac" "$javaClass")
+            fi
+            if [ -e "$BASE_DIR/.mvn/wrapper/MavenWrapperDownloader.class" ]; then
+                # Running the downloader
+                if [ "$MVNW_VERBOSE" = true ]; then
+                  echo " - Running MavenWrapperDownloader.java ..."
+                fi
+                ("$JAVA_HOME/bin/java" -cp .mvn/wrapper MavenWrapperDownloader "$MAVEN_PROJECTBASEDIR")
+            fi
+        fi
+    fi
+fi
+##########################################################################################
+# End of extension
+##########################################################################################
+
+export MAVEN_PROJECTBASEDIR=${MAVEN_BASEDIR:-"$BASE_DIR"}
+if [ "$MVNW_VERBOSE" = true ]; then
+  echo $MAVEN_PROJECTBASEDIR
+fi
+MAVEN_OPTS="$(concat_lines "$MAVEN_PROJECTBASEDIR/.mvn/jvm.config") $MAVEN_OPTS"
+
+# For Cygwin, switch paths to Windows format before running java
+if $cygwin; then
+  [ -n "$M2_HOME" ] &&
+    M2_HOME=`cygpath --path --windows "$M2_HOME"`
+  [ -n "$JAVA_HOME" ] &&
+    JAVA_HOME=`cygpath --path --windows "$JAVA_HOME"`
+  [ -n "$CLASSPATH" ] &&
+    CLASSPATH=`cygpath --path --windows "$CLASSPATH"`
+  [ -n "$MAVEN_PROJECTBASEDIR" ] &&
+    MAVEN_PROJECTBASEDIR=`cygpath --path --windows "$MAVEN_PROJECTBASEDIR"`
+fi
+
+# Provide a "standardized" way to retrieve the CLI args that will
+# work with both Windows and non-Windows executions.
+MAVEN_CMD_LINE_ARGS="$MAVEN_CONFIG $@"
+export MAVEN_CMD_LINE_ARGS
+
+WRAPPER_LAUNCHER=org.apache.maven.wrapper.MavenWrapperMain
+
+exec "$JAVACMD" \
+  $MAVEN_OPTS \
+  -classpath "$MAVEN_PROJECTBASEDIR/.mvn/wrapper/maven-wrapper.jar" \
+  "-Dmaven.home=${M2_HOME}" "-Dmaven.multiModuleProjectDirectory=${MAVEN_PROJECTBASEDIR}" \
+  ${WRAPPER_LAUNCHER} $MAVEN_CONFIG "$@"

mvnw.cmd

@@ -0,0 +1,182 @@
+@REM ----------------------------------------------------------------------------
+@REM Licensed to the Apache Software Foundation (ASF) under one
+@REM or more contributor license agreements.  See the NOTICE file
+@REM distributed with this work for additional information
+@REM regarding copyright ownership.  The ASF licenses this file
+@REM to you under the Apache License, Version 2.0 (the
+@REM "License"); you may not use this file except in compliance
+@REM with the License.  You may obtain a copy of the License at
+@REM
+@REM    https://www.apache.org/licenses/LICENSE-2.0
+@REM
+@REM Unless required by applicable law or agreed to in writing,
+@REM software distributed under the License is distributed on an
+@REM "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+@REM KIND, either express or implied.  See the License for the
+@REM specific language governing permissions and limitations
+@REM under the License.
+@REM ----------------------------------------------------------------------------
+
+@REM ----------------------------------------------------------------------------
+@REM Maven Start Up Batch script
+@REM
+@REM Required ENV vars:
+@REM JAVA_HOME - location of a JDK home dir
+@REM
+@REM Optional ENV vars
+@REM M2_HOME - location of maven2's installed home dir
+@REM MAVEN_BATCH_ECHO - set to 'on' to enable the echoing of the batch commands
+@REM MAVEN_BATCH_PAUSE - set to 'on' to wait for a keystroke before ending
+@REM MAVEN_OPTS - parameters passed to the Java VM when running Maven
+@REM     e.g. to debug Maven itself, use
+@REM set MAVEN_OPTS=-Xdebug -Xrunjdwp:transport=dt_socket,server=y,suspend=y,address=8000
+@REM MAVEN_SKIP_RC - flag to disable loading of mavenrc files
+@REM ----------------------------------------------------------------------------
+
+@REM Begin all REM lines with '@' in case MAVEN_BATCH_ECHO is 'on'
+@echo off
+@REM set title of command window
+title %0
+@REM enable echoing by setting MAVEN_BATCH_ECHO to 'on'
+@if "%MAVEN_BATCH_ECHO%" == "on"  echo %MAVEN_BATCH_ECHO%
+
+@REM set %HOME% to equivalent of $HOME
+if "%HOME%" == "" (set "HOME=%HOMEDRIVE%%HOMEPATH%")
+
+@REM Execute a user defined script before this one
+if not "%MAVEN_SKIP_RC%" == "" goto skipRcPre
+@REM check for pre script, once with legacy .bat ending and once with .cmd ending
+if exist "%HOME%\mavenrc_pre.bat" call "%HOME%\mavenrc_pre.bat"
+if exist "%HOME%\mavenrc_pre.cmd" call "%HOME%\mavenrc_pre.cmd"
+:skipRcPre
+
+@setlocal
+
+set ERROR_CODE=0
+
+@REM To isolate internal variables from possible post scripts, we use another setlocal
+@setlocal
+
+@REM ==== START VALIDATION ====
+if not "%JAVA_HOME%" == "" goto OkJHome
+
+echo.
+echo Error: JAVA_HOME not found in your environment. >&2
+echo Please set the JAVA_HOME variable in your environment to match the >&2
+echo location of your Java installation. >&2
+echo.
+goto error
+
+:OkJHome
+if exist "%JAVA_HOME%\bin\java.exe" goto init
+
+echo.
+echo Error: JAVA_HOME is set to an invalid directory. >&2
+echo JAVA_HOME = "%JAVA_HOME%" >&2
+echo Please set the JAVA_HOME variable in your environment to match the >&2
+echo location of your Java installation. >&2
+echo.
+goto error
+
+@REM ==== END VALIDATION ====
+
+:init
+
+@REM Find the project base dir, i.e. the directory that contains the folder ".mvn".
+@REM Fallback to current working directory if not found.
+
+set MAVEN_PROJECTBASEDIR=%MAVEN_BASEDIR%
+IF NOT "%MAVEN_PROJECTBASEDIR%"=="" goto endDetectBaseDir
+
+set EXEC_DIR=%CD%
+set WDIR=%EXEC_DIR%
+:findBaseDir
+IF EXIST "%WDIR%"\.mvn goto baseDirFound
+cd ..
+IF "%WDIR%"=="%CD%" goto baseDirNotFound
+set WDIR=%CD%
+goto findBaseDir
+
+:baseDirFound
+set MAVEN_PROJECTBASEDIR=%WDIR%
+cd "%EXEC_DIR%"
+goto endDetectBaseDir
+
+:baseDirNotFound
+set MAVEN_PROJECTBASEDIR=%EXEC_DIR%
+cd "%EXEC_DIR%"
+
+:endDetectBaseDir
+
+IF NOT EXIST "%MAVEN_PROJECTBASEDIR%\.mvn\jvm.config" goto endReadAdditionalConfig
+
+@setlocal EnableExtensions EnableDelayedExpansion
+for /F "usebackq delims=" %%a in ("%MAVEN_PROJECTBASEDIR%\.mvn\jvm.config") do set JVM_CONFIG_MAVEN_PROPS=!JVM_CONFIG_MAVEN_PROPS! %%a
+@endlocal & set JVM_CONFIG_MAVEN_PROPS=%JVM_CONFIG_MAVEN_PROPS%
+
+:endReadAdditionalConfig
+
+SET MAVEN_JAVA_EXE="%JAVA_HOME%\bin\java.exe"
+set WRAPPER_JAR="%MAVEN_PROJECTBASEDIR%\.mvn\wrapper\maven-wrapper.jar"
+set WRAPPER_LAUNCHER=org.apache.maven.wrapper.MavenWrapperMain
+
+set DOWNLOAD_URL="https://repo.maven.apache.org/maven2/io/takari/maven-wrapper/0.5.6/maven-wrapper-0.5.6.jar"
+
+FOR /F "tokens=1,2 delims==" %%A IN ("%MAVEN_PROJECTBASEDIR%\.mvn\wrapper\maven-wrapper.properties") DO (
+    IF "%%A"=="wrapperUrl" SET DOWNLOAD_URL=%%B
+)
+
+@REM Extension to allow automatically downloading the maven-wrapper.jar from Maven-central
+@REM This allows using the maven wrapper in projects that prohibit checking in binary data.
+if exist %WRAPPER_JAR% (
+    if "%MVNW_VERBOSE%" == "true" (
+        echo Found %WRAPPER_JAR%
+    )
+) else (
+    if not "%MVNW_REPOURL%" == "" (
+        SET DOWNLOAD_URL="%MVNW_REPOURL%/io/takari/maven-wrapper/0.5.6/maven-wrapper-0.5.6.jar"
+    )
+    if "%MVNW_VERBOSE%" == "true" (
+        echo Couldn't find %WRAPPER_JAR%, downloading it ...
+        echo Downloading from: %DOWNLOAD_URL%
+    )
+
+    powershell -Command "&{"^
+		"$webclient = new-object System.Net.WebClient;"^
+		"if (-not ([string]::IsNullOrEmpty('%MVNW_USERNAME%') -and [string]::IsNullOrEmpty('%MVNW_PASSWORD%'))) {"^
+		"$webclient.Credentials = new-object System.Net.NetworkCredential('%MVNW_USERNAME%', '%MVNW_PASSWORD%');"^
+		"}"^
+		"[Net.ServicePointManager]::SecurityProtocol = [Net.SecurityProtocolType]::Tls12; $webclient.DownloadFile('%DOWNLOAD_URL%', '%WRAPPER_JAR%')"^
+		"}"
+    if "%MVNW_VERBOSE%" == "true" (
+        echo Finished downloading %WRAPPER_JAR%
+    )
+)
+@REM End of extension
+
+@REM Provide a "standardized" way to retrieve the CLI args that will
+@REM work with both Windows and non-Windows executions.
+set MAVEN_CMD_LINE_ARGS=%*
+
+%MAVEN_JAVA_EXE% %JVM_CONFIG_MAVEN_PROPS% %MAVEN_OPTS% %MAVEN_DEBUG_OPTS% -classpath %WRAPPER_JAR% "-Dmaven.multiModuleProjectDirectory=%MAVEN_PROJECTBASEDIR%" %WRAPPER_LAUNCHER% %MAVEN_CONFIG% %*
+if ERRORLEVEL 1 goto error
+goto end
+
+:error
+set ERROR_CODE=1
+
+:end
+@endlocal & set ERROR_CODE=%ERROR_CODE%
+
+if not "%MAVEN_SKIP_RC%" == "" goto skipRcPost
+@REM check for post script, once with legacy .bat ending and once with .cmd ending
+if exist "%HOME%\mavenrc_post.bat" call "%HOME%\mavenrc_post.bat"
+if exist "%HOME%\mavenrc_post.cmd" call "%HOME%\mavenrc_post.cmd"
+:skipRcPost
+
+@REM pause the script if MAVEN_BATCH_PAUSE is set to 'on'
+if "%MAVEN_BATCH_PAUSE%" == "on" pause
+
+if "%MAVEN_TERMINATE_CMD%" == "on" exit %ERROR_CODE%
+
+exit /B %ERROR_CODE%

pom.xml

@@ -0,0 +1,59 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
+	<modelVersion>4.0.0</modelVersion>
+	<parent>
+		<groupId>org.springframework.boot</groupId>
+		<artifactId>spring-boot-starter-parent</artifactId>
+		<version>2.4.4</version>
+		<relativePath/> <!-- lookup parent from repository -->
+	</parent>
+	<groupId>com.example</groupId>
+	<artifactId>data-structure-service</artifactId>
+	<version>0.0.1-SNAPSHOT</version>
+	<name>demo</name>
+	<description>Demo project for Spring Boot</description>
+	<properties>
+		<java.version>1.8</java.version>
+	</properties>
+	<dependencies>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-jdbc</artifactId>
+		</dependency>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-thymeleaf</artifactId>
+		</dependency>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-web</artifactId>
+		</dependency>
+		<dependency>
+			<groupId>org.mybatis.spring.boot</groupId>
+			<artifactId>mybatis-spring-boot-starter</artifactId>
+			<version>2.1.4</version>
+		</dependency>
+
+		<dependency>
+			<groupId>mysql</groupId>
+			<artifactId>mysql-connector-java</artifactId>
+			<scope>runtime</scope>
+		</dependency>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-test</artifactId>
+			<scope>test</scope>
+		</dependency>
+	</dependencies>
+
+	<build>
+		<plugins>
+			<plugin>
+				<groupId>org.springframework.boot</groupId>
+				<artifactId>spring-boot-maven-plugin</artifactId>
+			</plugin>
+		</plugins>
+	</build>
+
+</project>

src/main/java/com/example/demo/DemoApplication.java

@@ -0,0 +1,13 @@
+package com.example.demo;
+
+import org.springframework.boot.SpringApplication;
+import org.springframework.boot.autoconfigure.SpringBootApplication;
+
+@SpringBootApplication
+public class DemoApplication {
+
+	public static void main(String[] args) {
+		SpringApplication.run(DemoApplication.class, args);
+	}
+
+}

src/main/resources/application.properties

@@ -0,0 +1 @@
+

src/test/java/com/example/demo/DemoApplicationTests.java

@@ -0,0 +1,13 @@
+package com.example.demo;
+
+import org.junit.jupiter.api.Test;
+import org.springframework.boot.test.context.SpringBootTest;
+
+@SpringBootTest
+class DemoApplicationTests {
+
+	@Test
+	void contextLoads() {
+	}
+
+}