hoge.java

import javax.tools.*;
import javax.tools.JavaCompiler.CompilationTask;
import java.io.IOException;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.net.URI;
import java.security.SecureClassLoader;
import java.util.Arrays;
import java.util.List;
import java.util.Locale;
import java.util.UUID;

public class CompileSourceInMemory {

    public static void main(String args[]) throws IOException {
        for (int i = 0; i < 2; i++) {
            // コンパイラの取得
            JavaCompiler compiler = ToolProvider.getSystemJavaCompiler();

            // コレクターの準備
            DiagnosticCollector<JavaFileObject> collector =
                    new DiagnosticCollector<>();

            try (
                    // 仮想ファイルマネージャの取得
                    StandardJavaFileManager fileManager
                            = compiler.getStandardFileManager(collector, null, null);
            ) {

                String uuid = UUID.randomUUID().toString().replace("-", "");
                String className = "HelloWorld_" + uuid;


                // コンパイルするファイルの準備
                String src =
                        "import java.util.concurrent.Callable;" +
                                "import java.util.Date;" +
                                "public class " + className + " {" +
                                "public static void main(String args[]) throws Exception {" +
                                "Callable<Date> callable = Date::new;" +
                                "System.out.println(callable.call());" +
                                "System.out.println(System.getProperties());" +
                                "Thread th = new Thread(() -> {System.out.println(\"hi!\");});th.run();" +
                                "System.out.println(\"This is in another java file\");" +
                                "}" +
                                "}";
                JavaFileObject file = new StringFileObject(className, src);


                Iterable<String> compileOptions = Arrays.asList("-d", "out\\production\\untitled2"/*, "-verbose"*/);

                List<? extends JavaFileObject> fileObjects = Arrays.asList(file);
                CompilationTask task = compiler.getTask(
                        null,
                        fileManager,
                        collector,
                        compileOptions,
                        null,
                        fileObjects
                );

                boolean success = task.call();
                for (Diagnostic<?> diagnostic : collector.getDiagnostics()) {
                    System.out.println(diagnostic.getKind() + " " + diagnostic.getMessage(Locale.getDefault()));
                    String sourceCode = ((StringFileObject) diagnostic.getSource()).getCode();

                    String a = sourceCode.substring(0, (int) diagnostic.getStartPosition());
                    String b = sourceCode.substring((int) diagnostic.getStartPosition(), (int) diagnostic.getEndPosition());
                    String c = sourceCode.substring((int) diagnostic.getEndPosition());
                    System.out.println(a + " >>>> " + b + " <<<< " + c);
                }
                System.out.println("Success: " + success);

                if (success) {
                    try {
                        ClassLoader classLoader = new MyClassLoader();
                        System.setSecurityManager(new SecurityManager());
                        Class<?> clazz = classLoader.loadClass(className);
                        Method method = clazz.getMethod("main", new Class[]{String[].class});
                        method.invoke(null, new Object[]{null});
                    } catch (ClassNotFoundException e) {
                        System.err.println("Class not found: " + e);
                    } catch (NoSuchMethodException e) {
                        System.err.println("No such method: " + e);
                    } catch (IllegalAccessException e) {
                        System.err.println("Illegal access: " + e);
                    } catch (InvocationTargetException e) {
                        System.err.println("Invocation target: " + e);
                        e.printStackTrace();
                    } finally {
                        System.setSecurityManager(null);
                    }
                }
            }
        }
    }
}

class MyClassLoader extends SecureClassLoader {
    MyClassLoader() {
        super();
    }
}

class StringFileObject extends SimpleJavaFileObject {

    private final String code;

    StringFileObject(String name, String code) {
        super(URI.create("string:///" + name.replace('.', '/') +
                Kind.SOURCE.extension), Kind.SOURCE);
        this.code = code;
    }

    @Override
    public CharSequence getCharContent(boolean ignoreEncodingErrors) {
        return code;
    }

    public String getCode() {
        return code;
    }
}