public Bindings getBindings(int scope) {
        
        if (scope == ScriptContext.GLOBAL_SCOPE) {
            return context.getBindings(ScriptContext.GLOBAL_SCOPE);
        } else if (scope == ScriptContext.ENGINE_SCOPE) {
            return context.getBindings(ScriptContext.ENGINE_SCOPE);
        } else {
            throw new IllegalArgumentException("Invalid scope value.");
        }
    }
    
    /**
     * Sets the <code>Bindings</code> with the corresponding scope value in the
     * <code>context</code> field.
     *
     * @param bindings The specified <code>Bindings</code>.
     * @param scope The specified scope.
     *
     * @throws IllegalArgumentException if the value of scope is
     * invalid for the type the <code>context</code> field.
     * @throws NullPointerException if the bindings is null and the scope is
     * <code>ScriptContext.ENGINE_SCOPE</code>
     */
    public void setBindings(Bindings bindings, int scope) {
        
        if (scope == ScriptContext.GLOBAL_SCOPE) {
            context.setBindings(bindings, ScriptContext.GLOBAL_SCOPE);;
        } else if (scope == ScriptContext.ENGINE_SCOPE) {
            context.setBindings(bindings, ScriptContext.ENGINE_SCOPE);;
        } else {
            throw new IllegalArgumentException("Invalid scope value.");
        }
    }
    
    /**
     * Sets the specified value with the specified key in the <code>ENGINE_SCOPE</code>
     * <code>Bindings</code> of the protected <code>context</code> field.
     *
     * @param key The specified key.
     * @param value The specified value.
     *
     * @throws NullPointerException if key is null.
     * @throws IllegalArgumentException if key is empty.
     */
    public void put(String key, Object value) {
        
        Bindings nn = getBindings(ScriptContext.ENGINE_SCOPE);
        if (nn != null) {
            nn.put(key, value);
        }
        
    }
    
    /**
     * Gets the value for the specified key in the <code>ENGINE_SCOPE</code> of the
     * protected <code>context</code> field.
     *
     * @return The value for the specified key.
     *
     * @throws NullPointerException if key is null.
     * @throws IllegalArgumentException if key is empty.
     */
    public Object get(String key) {
        
        Bindings nn = getBindings(ScriptContext.ENGINE_SCOPE);
        if (nn != null) {
            return nn.get(key);
        }
        
        return null;
    }
    
    
    /**
     * <code>eval(Reader, Bindings)</code> calls the abstract
     * <code>eval(Reader, ScriptContext)</code> method, passing it a <code>ScriptContext</code>
     * whose Reader, Writers and Bindings for scopes other that <code>ENGINE_SCOPE</code>
     * are identical to those members of the protected <code>context</code> field.  The specified
     * <code>Bindings</code> is used instead of the <code>ENGINE_SCOPE</code>
     *
     * <code>Bindings</code> of the <code>context</code> field.
     *
     * @param reader A <code>Reader</code> containing the source of the script.
     * @param bindings A <code>Bindings</code> to use for the <code>ENGINE_SCOPE</code>
     * while the script executes.
     *
     * @return The return value from <code>eval(Reader, ScriptContext)</code>
     * @throws ScriptException if an error occurs in script.
     * @throws NullPointerException if any of the parameters is null.
     */
    public Object eval(Reader reader, Bindings bindings ) throws ScriptException {
        
        ScriptContext ctxt = getScriptContext(bindings);
        
        return eval(reader, ctxt);
    }
    
    
    /**
     * Same as <code>eval(Reader, Bindings)</code> except that the abstract