Intellij Idea's debugger renders object to string in object view (Preferences -> Build, Execution, Deployment -> Debugger -> Data Views -> Java -> Enable 'toString()' object view). This behavior is enabled by default and it leads some strange problem when debug in Dubbo, for examples: #2431, or user may observe a ReferenceConfig may init twice or ReferenceConfig#urls may have two same entries if the breakpoint happens to set in the relevant places. You may interested in looking into the details from http://t.cn/EAhta27, where @code4wt gives the excellent analysis.
Class<?> parameterType = ReflectUtils.getBoxedClass(method.getReturnType());
                        if ("filter".equals(property) || "listener".equals(property)) {
                            parameterType = String.class;
                            value = StringUtils.join((String[]) value, ",");
                        } else if ("parameters".equals(property)) {
                            parameterType = Map.class;
                            value = CollectionUtils.toStringMap((String[]) value);
                        }
                        try {
                            Method setterMethod = getClass().getMethod(setter, parameterType);
                            setterMethod.invoke(this, value);
                        } catch (NoSuchMethodException e) {
                            
                        }
                    }
                } catch (Throwable e) {
                    logger.error(e.getMessage(), e);
                }
            }
        }
    }
    @Override
    public String toString() {
        try {
            StringBuilder buf = new StringBuilder();
            buf.append("<dubbo:");
            buf.append(getTagName(getClass()));
            Method[] methods = getClass().getMethods();
            for (Method method : methods) {
                try {