Initial Commit

.gitignore

+/target/
+/test-output/
+/.classpath
+/.project
+/.settings/

README

+# L2J Java Script Engine
+
+A JSR-223 implementation for Java.
+
+## Getting Started
+
+### Pre-requistites
+
+To build this project you will need [Java JDK](http://www.oracle.com/technetwork/java/javase/downloads/index.html) 10.0+ and [Maven](https://maven.apache.org/) 3.5+.
+
+### Build
+```
+$ mvn clean install
+```
+
+### Run tests
+```
+$ mvn test
+```
+
+### Versioning
+We use [SemVer](https://semver.org/) for versioning.
+
+### Auhtors
+Zoey76
+
+### License
+The project is under GPLv3, see [LICENSE](LICENSE) file.
\ No newline at end of file

pom.xml

+<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 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+	<modelVersion>4.0.0</modelVersion>
+	<groupId>com.l2jserver</groupId>
+	<artifactId>l2j-server-script-engine</artifactId>
+	<version>1.0.0-SNAPSHOT</version>
+	<name>L2J Server - Script Engine</name>
+	<inceptionYear>2018</inceptionYear>
+	<properties>
+		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+		<maven.compiler.source>10</maven.compiler.source>
+		<maven.compiler.target>10</maven.compiler.target>
+		<InMemoryJavaCompiler.version>1.3.0</InMemoryJavaCompiler.version>
+		<slf4j.version>1.7.25</slf4j.version>
+		<testng.version>6.14.3</testng.version>
+		<!-- Plugins -->
+		<maven-source-plugin.version>3.0.1</maven-source-plugin.version>
+		<maven-javadoc-plugin.version>3.0.1</maven-javadoc-plugin.version>
+		<maven-deploy-plugin.version>2.8.2</maven-deploy-plugin.version>
+		<jgitflow-maven-plugin.version>1.0-m5.1</jgitflow-maven-plugin.version>
+	</properties>
+	<developers>
+		<developer>
+			<id>Zoey76</id>
+		</developer>
+	</developers>
+	<dependencies>
+		<dependency>
+			<groupId>org.mdkt.compiler</groupId>
+			<artifactId>InMemoryJavaCompiler</artifactId>
+			<version>${InMemoryJavaCompiler.version}</version>
+		</dependency>
+		<dependency>
+			<groupId>org.slf4j</groupId>
+			<artifactId>slf4j-api</artifactId>
+			<version>${slf4j.version}</version>
+		</dependency>
+		<dependency>
+			<groupId>org.slf4j</groupId>
+			<artifactId>slf4j-simple</artifactId>
+			<version>${slf4j.version}</version>
+			<scope>provided</scope>
+		</dependency>
+		<dependency>
+			<groupId>org.testng</groupId>
+			<artifactId>testng</artifactId>
+			<version>${testng.version}</version>
+			<scope>test</scope>
+			<exclusions>
+				<exclusion>
+					<groupId>org.apache-extras.beanshell</groupId>
+					<artifactId>bsh</artifactId>
+				</exclusion>
+			</exclusions>
+		</dependency>
+	</dependencies>
+	<build>
+		<plugins>
+			<plugin>
+				<groupId>org.apache.maven.plugins</groupId>
+				<artifactId>maven-source-plugin</artifactId>
+				<version>${maven-source-plugin.version}</version>
+				<executions>
+					<execution>
+						<id>attach-sources</id>
+						<goals>
+							<goal>jar</goal>
+						</goals>
+					</execution>
+				</executions>
+			</plugin>
+			<plugin>
+				<groupId>org.apache.maven.plugins</groupId>
+				<artifactId>maven-javadoc-plugin</artifactId>
+				<version>${maven-javadoc-plugin.version}</version>
+				<configuration>
+					<additionalJOption>-html5</additionalJOption>
+				</configuration>
+			</plugin>
+			<plugin>
+				<groupId>org.apache.maven.plugins</groupId>
+				<artifactId>maven-deploy-plugin</artifactId>
+				<version>${maven-deploy-plugin.version}</version>
+			</plugin>
+			<plugin>
+				<groupId>external.atlassian.jgitflow</groupId>
+				<artifactId>jgitflow-maven-plugin</artifactId>
+				<version>${jgitflow-maven-plugin.version}</version>
+				<configuration>
+					<noDeploy>true</noDeploy>
+				</configuration>
+			</plugin>
+		</plugins>
+	</build>
+</project>
\ No newline at end of file

src/main/java/com/l2jserver/script/engine/JavaScriptEngine.java

+/*
+ * Copyright (C) 2018 L2J Server
+ * 
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ */
+package com.l2jserver.script.engine;
+
+import static com.l2jserver.script.engine.factory.JavaScriptEngineFactory.JAVA;
+import static com.l2jserver.script.engine.factory.JavaScriptEngineFactory.JAVA_LANGUAGE_VERSION;
+import static com.l2jserver.script.engine.tools.JavaEngineTools.evalScript;
+import static com.l2jserver.script.engine.tools.JavaEngineTools.readerToString;
+
+import java.io.Reader;
+
+import javax.script.AbstractScriptEngine;
+import javax.script.Bindings;
+import javax.script.Compilable;
+import javax.script.CompiledScript;
+import javax.script.ScriptContext;
+import javax.script.ScriptEngineFactory;
+import javax.script.ScriptException;
+import javax.script.SimpleBindings;
+
+import com.l2jserver.script.engine.factory.JavaScriptEngineFactory;
+import com.l2jserver.script.engine.script.JavaCompiledScript;
+
+/**
+ * Java Script Engine implementation.
+ * 
+ * @author Zoey76
+ */
+public class JavaScriptEngine extends AbstractScriptEngine implements Compilable {
+
+    public static final String CLASSLOADER = "ClassLoader";
+
+    public static final String CLASSPATH = "classpath";
+
+    public static final String MAINCLASS = "mainClass";
+
+    public static final String SOURCEPATH = "sourcepath";
+
+    private final ScriptEngineFactory scriptEngineFactory;
+
+    private static final String ENGINE_DESCRIPTION = "Engine " + JAVA + " v" + JAVA_LANGUAGE_VERSION;
+    
+    public JavaScriptEngine(ScriptEngineFactory scriptEngineFactory) {
+	this.scriptEngineFactory = scriptEngineFactory;
+    }
+
+    public JavaScriptEngine() {
+	this(new JavaScriptEngineFactory());
+    }
+
+    @Override
+    public Object eval(String script, ScriptContext context) throws ScriptException {
+	return evalScript(script, context);
+    }
+
+    @Override
+    public Object eval(Reader reader, ScriptContext context) throws ScriptException {
+	return eval(readerToString(reader), context);
+    }
+
+    @Override
+    public Bindings createBindings() {
+	return new SimpleBindings();
+    }
+
+    @Override
+    public ScriptEngineFactory getFactory() {
+	return scriptEngineFactory;
+    }
+
+    @Override
+    public CompiledScript compile(String script) throws ScriptException {
+	return new JavaCompiledScript(this, script);
+    }
+
+    @Override
+    public CompiledScript compile(Reader script) throws ScriptException {
+	return compile(readerToString(script));
+    }
+
+    @Override
+    public String toString() {
+	return ENGINE_DESCRIPTION;
+    }
+}

src/main/java/com/l2jserver/script/engine/factory/JavaScriptEngineFactory.java

+/*
+ * Copyright (C) 2018 L2J Server
+ * 
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ */
+package com.l2jserver.script.engine.factory;
+
+import java.util.Collections;
+import java.util.List;
+
+import javax.script.ScriptEngine;
+import javax.script.ScriptEngineFactory;
+
+import com.l2jserver.script.engine.JavaScriptEngine;
+
+/**
+ * Java Script Engine Factory implementation.
+ * 
+ * @author Zoey76
+ */
+public class JavaScriptEngineFactory implements ScriptEngineFactory {
+
+    public static final String JAVA = "Java";
+
+    public static final String JAVA_LANGUAGE_VERSION = "10.0.2";
+
+    private static final String THREADING = "THREADING";
+
+    private static final String MULTITHREADED = "MULTITHREADED";
+
+    private static final String EXTENSION = "java";
+
+    private static final String VERSION = "2.0";
+
+    private static final List<String> NAMES = List.of(JAVA);
+
+    private static final List<String> EXTENSIONS = List.of(EXTENSION);
+
+    private static final List<String> MIME_TYPES = Collections.emptyList();
+
+    private static long nextClassNum = 0L;
+
+    @Override
+    public String getEngineName() {
+	return JAVA;
+    }
+
+    @Override
+    public String getEngineVersion() {
+	return VERSION;
+    }
+
+    @Override
+    public List<String> getExtensions() {
+	return EXTENSIONS;
+    }
+
+    @Override
+    public String getLanguageName() {
+	return JAVA;
+    }
+
+    @Override
+    public String getLanguageVersion() {
+	return JAVA_LANGUAGE_VERSION;
+    }
+
+    @Override
+    public String getMethodCallSyntax(String obj, String m, String... args) {
+	final StringBuilder buf = new StringBuilder();
+	buf.append(obj);
+	buf.append('.');
+	buf.append(m);
+	buf.append('(');
+	if (args.length != 0) {
+	    int i = 0;
+	    for (; i < (args.length - 1); i++) {
+		buf.append(args[i] + ", ");
+	    }
+	    buf.append(args[i]);
+	}
+	buf.append(')');
+	return buf.toString();
+    }
+
+    @Override
+    public List<String> getMimeTypes() {
+	return MIME_TYPES;
+    }
+
+    @Override
+    public List<String> getNames() {
+	return NAMES;
+    }
+
+    @Override
+    public String getOutputStatement(String toDisplay) {
+	final StringBuilder buf = new StringBuilder();
+	buf.append("System.out.print(\"");
+	int len = toDisplay.length();
+	for (int i = 0; i < len; i++) {
+	    char ch = toDisplay.charAt(i);
+	    switch (ch) {
+	    case '"': {
+		buf.append("\\\"");
+		break;
+	    }
+	    case '\\': {
+		buf.append("\\\\");
+		break;
+	    }
+	    default: {
+		buf.append(ch);
+		break;
+	    }
+	    }
+	}
+	buf.append("\");");
+	return buf.toString();
+    }
+
+    @Override
+    public String getParameter(String key) {
+	if (ScriptEngine.ENGINE.equals(key)) {
+	    return getEngineName();
+	}
+	if (ScriptEngine.ENGINE_VERSION.equals(key)) {
+	    return getEngineVersion();
+	}
+	if (ScriptEngine.NAME.equals(key)) {
+	    return getEngineName();
+	}
+	if (ScriptEngine.LANGUAGE.equals(key)) {
+	    return getLanguageName();
+	}
+	if (ScriptEngine.LANGUAGE_VERSION.equals(key)) {
+	    return getLanguageVersion();
+	}
+	if (THREADING.equals(key)) {
+	    return MULTITHREADED;
+	}
+	return null;
+    }
+
+    @Override
+    public String getProgram(String... statements) {
+	final StringBuilder buf = new StringBuilder();
+	buf.append("class ");
+	buf.append(getClassName());
+	buf.append(" {\n");
+	buf.append("    public static void main(String[] args) {\n");
+	if (statements.length != 0) {
+	    for (String statement : statements) {
+		buf.append("        ");
+		buf.append(statement);
+		buf.append(";\n");
+	    }
+	}
+	buf.append("    }\n");
+	buf.append("}\n");
+	return buf.toString();
+    }
+
+    @Override
+    public ScriptEngine getScriptEngine() {
+	return new JavaScriptEngine();
+    }
+
+    private String getClassName() {
+	return "com_sun_script_java_Main$" + getNextClassNumber();
+    }
+
+    private static synchronized long getNextClassNumber() {
+	return nextClassNum++;
+    }
+}

src/main/java/com/l2jserver/script/engine/script/JavaCompiledScript.java

+/*
+ * Copyright (C) 2018 L2J Server
+ * 
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ */
+package com.l2jserver.script.engine.script;
+
+import javax.script.CompiledScript;
+import javax.script.ScriptContext;
+import javax.script.ScriptEngine;
+import javax.script.ScriptException;
+
+import com.l2jserver.script.engine.JavaScriptEngine;
+
+/**
+ * Java Compiled Script implementation.
+ * 
+ * @author Zoey76
+ */
+public class JavaCompiledScript extends CompiledScript {
+
+    private final JavaScriptEngine scriptEngine;
+
+    private final String script;
+
+    public JavaCompiledScript(JavaScriptEngine scriptEngine, String script) {
+	this.scriptEngine = scriptEngine;
+	this.script = script;
+    }
+
+    @Override
+    public Object eval(ScriptContext context) throws ScriptException {
+	return scriptEngine.eval(script, context);
+    }
+
+    @Override
+    public ScriptEngine getEngine() {
+	return scriptEngine;
+    }
+}
\ No newline at end of file

src/main/java/com/l2jserver/script/engine/tools/JavaEngineTools.java

+/*
+ * Copyright (C) 2018 L2J Server
+ * 
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ */
+package com.l2jserver.script.engine.tools;
+
+import static com.l2jserver.script.engine.JavaScriptEngine.CLASSLOADER;
+import static com.l2jserver.script.engine.JavaScriptEngine.CLASSPATH;
+import static com.l2jserver.script.engine.JavaScriptEngine.MAINCLASS;
+import static javax.script.ScriptContext.ENGINE_SCOPE;
+
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.Reader;
+import java.lang.reflect.Method;
+import java.lang.reflect.Modifier;
+
+import javax.script.ScriptContext;
+import javax.script.ScriptException;
+
+import org.mdkt.compiler.InMemoryJavaCompiler;
+
+/**
+ * Java Engine Tools.
+ * 
+ * @author Zoey76
+ */
+public class JavaEngineTools {
+
+    private static final String CONTEXT = "context";
+
+    private static final String ARGUMENTS = "arguments";
+
+    private static final String SET_SCRIPT_CONTEXT = "setScriptContext";
+
+    private static final String MAIN = "main";
+
+    private static final String[] EMPTY_STRING_ARRAY = new String[0];
+
+    private static final Class<?>[] ARG_SCRIPT_CONTEXT = new Class[] { ScriptContext.class };
+
+    private static final Class<?>[] ARG_MAIN = new Class[] { String[].class };
+
+    private static final InMemoryJavaCompiler COMPILER = InMemoryJavaCompiler.newInstance();
+
+    public static Object evalScript(String script, ScriptContext context) throws ScriptException {
+	// JSR-223 requirement
+	context.setAttribute(CONTEXT, context, ENGINE_SCOPE);
+
+	try {
+	    final Class<?> clazz = COMPILER
+		    .useOptions("-" + CLASSPATH, context.getAttribute(CLASSPATH, ENGINE_SCOPE).toString()) //
+		    .useParentClassLoader((ClassLoader) context.getAttribute(CLASSLOADER, ENGINE_SCOPE)) //
+		    .addSource(context.getAttribute(MAINCLASS, ENGINE_SCOPE).toString(), script) //
+		    .compile(context.getAttribute(MAINCLASS, ENGINE_SCOPE).toString(), script);
+	    final boolean isPublicClazz = Modifier.isPublic(clazz.getModifiers());
+	    final Method setCtxMethod = findMethod(clazz, SET_SCRIPT_CONTEXT, ARG_SCRIPT_CONTEXT);
+	    if (setCtxMethod != null) {
+		if (!isPublicClazz) {
+		    setCtxMethod.setAccessible(true);
+		}
+		setCtxMethod.invoke(null, new Object[] { context });
+	    }
+
+	    final Method mainMethod = findMethod(clazz, MAIN, ARG_MAIN);
+	    if (mainMethod != null) {
+		if (!isPublicClazz) {
+		    mainMethod.setAccessible(true);
+		}
+
+		final String args[] = getArguments(context);
+
+		mainMethod.invoke(null, new Object[] { args });
+	    }
+	    return clazz;
+	} catch (Exception ex) {
+	    throw new ScriptException(ex);
+	}
+    }
+
+    public static String readerToString(Reader reader) throws ScriptException {
+	try (BufferedReader in = new BufferedReader(reader)) {
+	    final StringBuilder result = new StringBuilder();
+	    String line = null;
+	    while ((line = in.readLine()) != null) {
+		result.append(line).append(System.lineSeparator());
+	    }
+	    return result.toString();
+	} catch (IOException ex) {
+	    throw new ScriptException(ex);
+	}
+    }
+
+    private static Method findMethod(Class<?> clazz, String methodName, Class<?>[] args) {
+	try {
+	    final Method mainMethod = clazz.getMethod(methodName, args);
+	    final int modifiers = mainMethod.getModifiers();
+	    if (Modifier.isPublic(modifiers) && Modifier.isStatic(modifiers)) {
+		return mainMethod;
+	    }
+	} catch (NoSuchMethodException nsme) {
+	}
+	return null;
+    }
+
+    private static String[] getArguments(ScriptContext ctx) {
+	int scope = ctx.getAttributesScope(ARGUMENTS);
+	if (scope != -1) {
+	    Object obj = ctx.getAttribute(ARGUMENTS, scope);
+	    if (obj instanceof String[]) {
+		return (String[]) obj;
+	    }
+	}
+	return EMPTY_STRING_ARRAY;
+    }
+}

src/main/resources/META-INF/services/javax.script.ScriptEngineFactory

+com.l2jserver.script.engine.factory.JavaScriptEngineFactory
\ No newline at end of file

src/test/java/com/l2jserver/script/compiler/JavaCompilerTest.java

+/*
+ * Copyright (C) 2018 L2J Server
+ * 
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ */
+package com.l2jserver.script.compiler;
+
+import static com.l2jserver.script.engine.JavaScriptEngine.CLASSLOADER;
+import static com.l2jserver.script.engine.JavaScriptEngine.CLASSPATH;
+import static com.l2jserver.script.engine.JavaScriptEngine.MAINCLASS;
+import static javax.script.ScriptContext.ENGINE_SCOPE;
+import static javax.script.ScriptEngine.FILENAME;
+
+import java.io.BufferedReader;
+import java.io.FileInputStream;
+import java.io.InputStreamReader;
+import java.lang.reflect.Method;
+
+import javax.script.Compilable;
+import javax.script.CompiledScript;
+import javax.script.ScriptEngine;
+import javax.script.ScriptEngineManager;
+
+import org.testng.Assert;
+import org.testng.annotations.Test;
+
+/**
+ * Java Compiler test.
+ *
+ * @author Zoey76
+ */
+public class JavaCompilerTest {
+
+    private static final String CLASS_PATH = "src/test/resources/";
+
+    private static final String CLASS = "TestClass";
+
+    private static final String EXTENSION = "java";
+
+    private static final String PACKAGE_PATH = "com/l2jserver/script/java/";
+
+    private static final String PACKAGE = "com.l2jserver.script.java";
+
+    private static final String METHOD_NAME = "main";
+
+    @Test
+    void testJavaCompiler() throws Exception {
+	final ScriptEngineManager sem = new ScriptEngineManager();
+	final ScriptEngine scriptEngine = sem.getEngineByExtension(EXTENSION);
+	scriptEngine.getContext().setAttribute(CLASSPATH, CLASS_PATH, ENGINE_SCOPE);
+	scriptEngine.getContext().setAttribute(MAINCLASS, PACKAGE + "." + CLASS, ENGINE_SCOPE);
+	scriptEngine.getContext().setAttribute(FILENAME, CLASS + "." + EXTENSION, ENGINE_SCOPE);
+	scriptEngine.getContext().setAttribute(CLASSLOADER, getClass().getClassLoader(), ENGINE_SCOPE);
+
+	try (FileInputStream fis = new FileInputStream(CLASS_PATH + PACKAGE_PATH + CLASS + "." + EXTENSION);
+		InputStreamReader isr = new InputStreamReader(fis);
+		BufferedReader br = new BufferedReader(isr)) {
+
+	    final Compilable compilableEngine = (Compilable) scriptEngine;
+	    final CompiledScript compiledScript = compilableEngine.compile(br);
+	    final Class<?> scriptClass = (Class<?>) compiledScript.eval(scriptEngine.getContext());
+	    Assert.assertEquals(scriptClass.getName(), PACKAGE + "." + CLASS);
+	    Assert.assertEquals(scriptClass.getPackageName(), PACKAGE);
+
+	    final Method main = scriptClass.getMethod(METHOD_NAME, String[].class);
+	    final Object script = scriptClass.getDeclaredConstructor().newInstance();
+	    main.invoke(script, (Object) (String[]) null);
+	}
+    }
+}

src/test/resources/com/l2jserver/script/java/TestClass.java

+/*
+ * Copyright (C) 2018 L2J Server
+ * 
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ */
+package com.l2jserver.script.java;
+
+import java.lang.reflect.Method;
+
+import com.l2jserver.script.java.child.ChildTestClass;
+
+/**
+ * Test class example.
+ * 
+ * @author Zoey76
+ */
+public class TestClass {
+
+    public static void main(String[] args) throws Exception {
+	final Method m = ChildTestClass.class.getMethod("getCountries");
+	final ChildTestClass child = ChildTestClass.class.getDeclaredConstructor().newInstance();
+	System.out.println(m.invoke(child));
+    }
+}

src/test/resources/com/l2jserver/script/java/child/ChildTestClass.java

+/*
+ * Copyright (C) 2018 L2J Server
+ * 
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ */
+package com.l2jserver.script.java.child;
+
+import java.util.List;
+
+/**
+ * Child test class example.
+ * 
+ * @author Zoey76
+ */
+public class ChildTestClass extends ParentChildTestClass {
+
+    @Override
+    public String getCountries() {
+	// Java 10/9/8
+	var countries = List.of("France", "Bulgaria", "Germany");
+	return String.join(", ", countries);
+    }
+}

src/test/resources/com/l2jserver/script/java/child/ParentChildTestClass.java

+/*
+ * Copyright (C) 2018 L2J Server
+ * 
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ * 
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ * 
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ */
+package com.l2jserver.script.java.child;
+
+/**
+ * Child test class example.
+ * 
+ * @author Zoey76
+ */
+public abstract class ParentChildTestClass {
+    abstract String getCountries();
+}