注解扫描工具-白红宇

注解扫描工具

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发布时间：2019-06-26

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package com.test.scaner;import static org.slf4j.LoggerFactory.getLogger;import java.io.File;import java.io.IOException;import java.lang.annotation.Annotation;import java.net.URL;import java.util.ArrayList;import java.util.Arrays;import java.util.HashMap;import java.util.List;import java.util.Map;import java.util.Map.Entry;import org.apache.commons.lang3.StringUtils;import org.slf4j.Logger;import com.google.common.collect.Lists;import eu.infomas.annotation.AnnotationDetector;import eu.infomas.annotation.AnnotationDetector.Reporter;import eu.infomas.annotation.AnnotationDetector.TypeReporter;/** *  * Created by linjinzhi on 2016/11/18 * */public class AnnotationScanUtils {		private static final Logger log = getLogger(AnnotationScanUtils.class);		private AnnotationScanUtils(){}		private static List
    
     > supportAnnotationClasses = new ArrayList<>();//特定注解作用下的类类型列表		private static Map
     
      , Class
      > classesMap = null;//类类型-注解类型映射			/**	 * 初始化列表和Map	 * @param annotaionType 用户自定义注解类型.	 * @param supportAnnotationPackage 注解作用下的类所在包	 */	private static void init(Class
       annotaionType, String supportAnnotationPackage) {				if(StringUtils.isNotBlank(supportAnnotationPackage)){						String[] sitenameClazzArray = StringUtils.split(supportAnnotationPackage, ";");                        classesMap = scan(annotaionType, sitenameClazzArray);             for(Entry
      
       , Class
       > entry : classesMap.entrySet()) {            	supportAnnotationClasses.add(entry.getKey());            }        }	}			/**	 * 得到特定包下的特定注解作用的Class	 * @param annotaionType 要求扫描的注解类型	 * @param supportAnnotationPackage 扫描的包名称，如果有多个，则以';'分隔 	 * @return 被特定注解作用且位于制定包下的所有具体类类型列表	 */	public static List
       
        > getSupportClasses(Class
         annotaionType, String supportAnnotationPackage) {				init(annotaionType, supportAnnotationPackage);				return supportAnnotationClasses;	}				/**	 * 得到类类型-注解类型映射	 * @return	 */	public static Map
        
         , Class
         > getObjectAnnotationMap(Class
          annotaionType, String supportAnnotationPackage) {				init(annotaionType, supportAnnotationPackage);				return classesMap;	}			/**     * 扫描类注解.     *     * @param annotationClass     * @param packages     * @return     */    private static Map
         
          , Class
          > scan( final Class
           annotationClass, String... packages) { final Map
          
           , Class
           > classesMap = new HashMap<>(); final Reporter reporter = new TypeReporter() { @SuppressWarnings("unchecked") @Override public Class
           [] annotations() { return new Class[] { annotationClass }; } @Override public void reportTypeAnnotation( Class
            annotation, String className) { try { classesMap.put(Class.forName(className), annotation); } catch (ClassNotFoundException e) { log.error("Class not found: {}", className, e); } } }; startScan(reporter, packages); return classesMap; } private static void startScan( final AnnotationDetector.Reporter reporter, String... packageNames) { final AnnotationDetector cf = new AnnotationDetector(reporter); try { if (packageNames.length == 0) { // 解决在web容器下扫描不到类的问题. URL url = Thread.currentThread().getContextClassLoader() .getResource(""); File file = new File(url.getPath()); File[] files = file.listFiles( (File pathname) -> pathname.isDirectory() && !pathname.isHidden() ); List
           
             fileNames = Lists.newLinkedList(); for (File one : files) { fileNames.add(one.getName()); } log.debug("san path:{}", fileNames); cf.detect(fileNames.toArray(new String[fileNames.size()])); // 这里扫描全部可能会有性能问题 // XXX 在java项目中可以扫描到jar文件中的类，在web项目中不行. cf.detect(); } else { cf.detect(packageNames); } } catch (IOException e) { log.error("scan package error packages:{}", Arrays.toString(packageNames), e); } } /** * test * @param args */ public static void main(String[] args) { List
            
             > classes = AnnotationScanUtils.getSupportClasses(Crawler.class, "com.test.scaner;"); for(Class
              clazz : classes) { System.out.println(clazz); } Map
             
              , Class
              > map = AnnotationScanUtils.getObjectAnnotationMap(Crawler.class, "com.test.scaner;"); for(Entry
              
               , Class
               > entry : map.entrySet()) { System.out.println(entry.getKey()+"\t"+entry.getValue()); } }}