public void test_execute_scriptEngineReturnsNull() {
        // Setup engine that returns null
        scriptEngineFactory.add("nullEngine", new ScriptEngine() {
            @Override
            public Object evaluate(String template, Map<String, Object> paramMap) {
                return null;
            }
        });

        // Execute and verify null result

   * IllegalStateException} if it is accessed in any way, with the following exceptions:
   *
   * <ul>
   *   <li>{@code view.equals(view)} evaluates to {@code true} (but any other {@code equals()}
   *       expression involving {@code view} will throw)
   *   <li>{@code hashCode()} does not throw

        ComponentUtil.register(scriptEngineFactory, "scriptEngineFactory");
        new AbstractScriptEngine() {

            @Override
            public Object evaluate(String template, Map<String, Object> paramMap) {
                final Map<String, Object> bindingMap = new HashMap<>(paramMap);
                bindingMap.put("container", SingletonLaContainerFactory.getContainer());

    }

    @Override
    public Object evaluate(final String template, final Map<String, Object> paramMap) {
        final Map<String, Object> bindingMap = new HashMap<>(paramMap);
        bindingMap.put("container", SingletonLaContainerFactory.getContainer());
        final GroovyShell groovyShell = new GroovyShell(new Binding(bindingMap));
        try {
            return groovyShell.evaluate(template);

        }

        @Override
        public Object evaluate(String template, Map<String, Object> paramMap) {
            return "TestEngine[" + identifier + "]: " + template;
        }
    }

    private static class CustomScriptEngine implements ScriptEngine {
        @Override
        public Object evaluate(String template, Map<String, Object> paramMap) {
            return "CustomEngine: " + template;

        boostFunctionList.add(new FilterFunctionBuilder(filter, scoreFunction));
    }

    /**
     * Gets an array of rescorer builders for post-processing search results.
     * This method evaluates all configured query rescorers with the provided parameters.
     *
     * @param params parameters to pass to the rescorers during evaluation
     * @return an array of rescorer builders, filtered to exclude null values

        ComponentUtil.register(scriptEngineFactory, "scriptEngineFactory");
        new AbstractScriptEngine() {

            @Override
            public Object evaluate(String template, Map<String, Object> paramMap) {
                final Map<String, Object> bindingMap = new HashMap<>(paramMap);
                bindingMap.put("container", SingletonLaContainerFactory.getContainer());

   * data written to it to the underlying {@link OutputStream}.
   *
   * <p>The {@link OutputStream} should not be written to before or after the hand-off.
   */
  // TODO(user): Evaluate whether it makes sense to always piggyback the computation of a
  // HashCode on an existing OutputStream, compared to creating a separate OutputStream that could

        final Map<String, Object> params = new HashMap<>();
        params.put("executor", this);

        return ComponentUtil.getScriptEngineFactory().getScriptEngine(scriptType).evaluate(script, params);
    }

    /**
     * Default constructor.
     */
    public LtrQueryRescorer() {
        // Default constructor
    }

    @Override
    public RescorerBuilder<?> evaluate(final Map<String, Object> params) {
        final FessConfig fessConfig = ComponentUtil.getFessConfig();
        final String modelName = fessConfig.getLtrModelName();
        if (StringUtil.isBlank(modelName)) {