![image](https://user-images.githubusercontent.com/54169514/199922630-ba1b1417-e124-40b1-bac7-49158e2adbca.png)

文档上ApplicationConfig的enableFileCache属性默认true，但是在Dubbo3.1版本中，该属性似乎默认为null，导致mapping和元数据无法在本地缓存。

![image](https://user-images.githubusercontent.com/54169514/199923129-c99ea29b-45c5-40d1-bc21-1fbb44830fc7.png)

void testOverrideConfigById() {
        String owner = "tom2";
        SysProps.setProperty("dubbo.applications.demo-app.owner", owner);
        SysProps.setProperty("dubbo.applications.demo-app.version", "1.2.3");
        SysProps.setProperty("dubbo.applications.demo-app.name", "demo-app");
        ApplicationConfig applicationConfig = new ApplicationConfig();
        applicationConfig.setId("demo-app");
        DubboBootstrap.getInstance()
                .application(applicationConfig)
                .initialize();
        Assertions.assertEquals("demo-app", applicationConfig.getId());
        Assertions.assertEquals("demo-app", applicationConfig.getName());
        Assertions.assertEquals(owner, applicationConfig.getOwner());
        Assertions.assertEquals("1.2.3", applicationConfig.getVersion());
        DubboBootstrap.getInstance().destroy();
    }
    @Test
    void testOverrideConfigByName() {
        String owner = "tom3";
        SysProps.setProperty("dubbo.applications.demo-app.owner", owner);
        SysProps.setProperty("dubbo.applications.demo-app.version", "1.2.3");
        ApplicationConfig applicationConfig = new ApplicationConfig();
        applicationConfig.setName("demo-app");
        DubboBootstrap.getInstance()
                .application(applicationConfig)
                .initialize();
        Assertions.assertEquals(owner, applicationConfig.getOwner());
        Assertions.assertEquals("1.2.3", applicationConfig.getVersion());
        DubboBootstrap.getInstance().destroy();
    }