之前有遇到過本地測試跑的通的程式碼，上到線上就失敗的情況，當時是一個檔案處理的操作。

後面才發現spring boot打的jar包，和直接本地用IDEA執行的程式碼多多少少還是有區別的，再一個就是windonws和linux系統，也多多少少有點不同。

這回寫了掃描包程式碼，然後用jar測試了下，

下面是兩個獲取某個包下所有有特定註解類的程式碼，都是網上copy的

/**
* 不可用於jar
*/
public List<Class<?>> a() {
        List<Class<?>> classList = new ArrayList<>();
        ResourcePatternResolver resolver 
 
= new PathMatchingResourcePatternResolver();
        MetadataReaderFactory metaReader = new CachingMetadataReaderFactory();
        try {
            Resource[] resources = resolver.getResources("classpath*:com/bzua/jingdata/service/**/*.class");
            ClassLoader loader = ClassLoader.getSystemClassLoader();
            
 
for (Resource resource : resources) {
                MetadataReader reader = metaReader.getMetadataReader(resource);
                String className = reader.getClassMetadata().getClassName();
                Class<?> clazz = loader.loadClass(className);
                if (clazz.isAnnotationPresent(Report.class
 
)) {
                    classList.add(clazz);
                }
            }
        } catch (ClassNotFoundException | IOException e) {
            log.error("錯誤資訊: ", e);
        }
        return classList;
    }

    
　　/**
　　* 可用於jar
　　*/

    public List<Class<?>> b() {
        List<Class<?>> classList = new ArrayList<>();

        ResourcePatternResolver resourcePatternResolver = new PathMatchingResourcePatternResolver();
        final String BASE_PACKAGE = "com.bzua.jingdata.service";
        final String RESOURCE_PATTERN = "/**/*.class";
        try {
            String pattern = ResourcePatternResolver.CLASSPATH_ALL_URL_PREFIX +
                    ClassUtils.convertClassNameToResourcePath(BASE_PACKAGE) + RESOURCE_PATTERN;
            Resource[] resources = resourcePatternResolver.getResources(pattern);
            //MetadataReader 的工廠類
            MetadataReaderFactory readerfactory = new CachingMetadataReaderFactory(resourcePatternResolver);
            for (Resource resource : resources) {
                //用於讀取類資訊
                MetadataReader reader = readerfactory.getMetadataReader(resource);
                //掃描到的class
                String classname = reader.getClassMetadata().getClassName();
                Class<?> clazz = Class.forName(classname);
                //判斷是否有指定主解
                if (clazz.isAnnotationPresent(Report.class)) {
                    classList.add(clazz);
                }
            }
        } catch (IOException | ClassNotFoundException e) {
        }
        return classList;
    }