Core functionality to calculate metrics of single method

.gitignore

@@ -21,3 +21,13 @@
 
 # virtual machine crash logs, see http://www.java.com/en/download/help/error_hotspot.xml
 hs_err_pid*
+
+# gradle files
+.gradle
+build
+
+# Avoid ignoring Gradle wrapper jar file (.jar files are usually ignored)
+!gradle-wrapper.jar
+
+# IDEA project files
+.idea

PMDRuleSet.xml

@@ -0,0 +1,34 @@
+<?xml version="1.0"?>
+
+<ruleset name="Custom Rules"
+         xmlns="http://pmd.sourceforge.net/ruleset/2.0.0"
+         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://pmd.sourceforge.net/ruleset/2.0.0 https://pmd.sourceforge.io/ruleset_2_0_0.xsd">
+
+    <description>
+        My custom rules
+    </description>
+
+
+    <rule ref="category/java/bestpractices.xml">
+        <exclude name="SystemPrintln"/>
+    </rule>
+    <rule ref="category/java/codestyle.xml">
+        <exclude name="AtLeastOneConstructor"/>
+    </rule>
+    <rule ref="category/java/design.xml" />
+    <rule ref="category/java/errorprone.xml" />
+
+    <rule ref="category/java/codestyle.xml/LongVariable">
+        <properties>
+            <property name="minimum" value="30" />
+        </properties>
+    </rule>
+
+    <rule ref="category/java/bestpractices.xml/JUnitTestContainsTooManyAsserts">
+        <properties>
+            <property name="maximumAsserts" value="5" />
+        </properties>
+    </rule>
+
+</ruleset>

build.gradle

@@ -0,0 +1,53 @@
+apply plugin: 'java'
+apply plugin: 'application'
+apply plugin: 'pmd'
+
+group 'com.github'
+version '1.0-SNAPSHOT'
+
+repositories {
+    mavenCentral()
+}
+
+dependencies {
+    implementation group: 'net.sourceforge.pmd', name: 'pmd-java', version: '6.29.0'
+    implementation 'info.picocli:picocli:4.5.2'
+
+    testImplementation(platform('org.junit:junit-bom:5.7.0'))
+    testImplementation('org.junit.jupiter:junit-jupiter')
+
+    testRuntimeOnly("org.junit.jupiter:junit-jupiter-engine:5.7.0")
+}
+
+pmd {
+    consoleOutput = true
+    ruleSetFiles = files("PMDRuleSet.xml")
+}
+
+test {
+    useJUnitPlatform()
+}
+
+application {
+    mainClassName = 'com.github.emcat.Emcat'
+    applicationDefaultJvmArgs = ["--enable-preview"]
+}
+
+run{
+    standardInput = System.in
+}
+
+sourceCompatibility = 14
+targetCompatibility = 14
+
+tasks.withType(JavaCompile) {
+    options.compilerArgs += '--enable-preview'
+}
+
+tasks.withType(Test) {
+    jvmArgs += "--enable-preview"
+}
+
+tasks.withType(JavaExec) {
+    jvmArgs += '--enable-preview'
+}

gradle/wrapper/gradle-wrapper.properties

@@ -0,0 +1,5 @@
+distributionBase=GRADLE_USER_HOME
+distributionPath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-6.3-bin.zip
+zipStoreBase=GRADLE_USER_HOME
+zipStorePath=wrapper/dists