在封裝fastdfs客戶端的時候，發(fā)現(xiàn)在本地運行能夠獲取到配置文件的路徑

 /**
     * 初始化客戶端
     * ClientGlobal.init(filePath) 讀取并初始化客戶端
     */
    static {
        try {
            String filePath = new ClassPathResource("fdfs_client.conf").getFile().getAbsolutePath();
            logger.info("初始化filePath{}",filePath);
            ClientGlobal.init(filePath);
        } catch (Exception e) {
            logger.error("初始化FastDFS失敗", e.getMessage());
        }
    }

結(jié)果：

打包前

打成jar包之后就無法獲取文件了，原因是resource目錄會打包到j(luò)ar包的目錄，我們上傳文件到服務(wù)器，肯定不會讀取這個絕對路徑，而是讀取打包后resource下的文件，所以絕對路徑就行不通了，找不到文件就是情理之中的了。
查閱資料后發(fā)現(xiàn)，打包后是一個jar包，無法直接讀取jar包中的文件，讀取只能通過類加載器讀取。類加載器讀取jar包中編譯后的class文件，自然就能讀取到我們想要的conf文件。解壓jar包后查看目錄結(jié)構(gòu)，發(fā)現(xiàn)yml和conf都在class下：

image.png

然后我們可以根據(jù)yml讀取的原理來讀取這個配置文件即可
翻閱springboot的run實現(xiàn)源碼，找到讀取方式

image.png

public ConfigurableApplicationContext run(String... args) {
        StopWatch stopWatch = new StopWatch();
        stopWatch.start();
        DefaultBootstrapContext bootstrapContext = createBootstrapContext();
        ConfigurableApplicationContext context = null;
        configureHeadlessProperty();
        SpringApplicationRunListeners listeners = getRunListeners(args);
        listeners.starting(bootstrapContext, this.mainApplicationClass);
        try {
            ApplicationArguments applicationArguments = new DefaultApplicationArguments(args);
            //看到這行，初始化環(huán)境
            ConfigurableEnvironment environment = prepareEnvironment(listeners, bootstrapContext, applicationArguments);
            configureIgnoreBeanInfo(environment);

                    /*注釋掉部分代碼*/

        }
        catch (Throwable ex) {
            handleRunFailure(context, ex, listeners);
            throw new IllegalStateException(ex);
        }
        return context;
    }

    private ConfigurableEnvironment prepareEnvironment(SpringApplicationRunListeners listeners,
            DefaultBootstrapContext bootstrapContext, ApplicationArguments applicationArguments) {
        // Create and configure the environment
        ConfigurableEnvironment environment = getOrCreateEnvironment();
        configureEnvironment(environment, applicationArguments.getSourceArgs());
        ConfigurationPropertySources.attach(environment);
        listeners.environmentPrepared(bootstrapContext, environment);
        DefaultPropertiesPropertySource.moveToEnd(environment);
        configureAdditionalProfiles(environment);
        bindToSpringApplication(environment);
        if (!this.isCustomEnvironment) {
            environment = new EnvironmentConverter(getClassLoader()).convertEnvironmentIfNecessary(environment,
                    deduceEnvironmentClass());
        }
        ConfigurationPropertySources.attach(environment);
        return environment;
    }