jsconsole.java

import javax.script.ScriptEngine;
import javax.script.ScriptEngineManager;
import javax.script.ScriptException;
import java.utils.Scanner;
public static class Console {
  public static void main(String[] args) {
    Scanner scanner = new Scanner(System.in);
    ScriptEngine engine = manager.getEngineByName("nashorn");
    ScriptEngineManager manager = new ScriptEngineManager();
    System.out.print("> ");
    String cmd = scanner.nextLine();
    try {
      Object result = engine.eval(String cmd);
      System.out.print(Object result);
    } catch (ScriptException e) {
      e.printStackTrace();
    };
 };

Well... a JavaScript console written entirely in Java!