package com.cgx.logtest1;

import java.lang.reflect.Constructor;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.core.io.Resource;
import org.springframework.core.io.support.PathMatchingResourcePatternResolver;
 
import org.springframework.util.ResourceUtils;

public class BuildCla {
    private Logger log = LoggerFactory.getLogger(getClass());
    private static final String PACKET_CLASS = "com/cgx/logtest1/*.class";
    private static final String CLASS_PREFIX = "com.cgx.logtest1.";
    private static final String CLASS_SUFFIX = ".class";

    
 
public List<Object> searchAndBuild() {
        log.info("開始查詢類檔案...");
        long start = System.currentTimeMillis();
        // 獲取當前執行緒上下文類載入器
        ClassLoader appClassLoader = Thread.currentThread()
                .getContextClassLoader();

        List<Object> registerClasses = new
 
 ArrayList<>();
        int total = 0;
        Resource[] resources = new Resource[0];
        try {
            // 找到包路徑下的所有類檔案
            resources = new PathMatchingResourcePatternResolver().getResources(
                    ResourceUtils.CLASSPATH_URL_PREFIX + PACKET_CLASS);

            if (resources.length == 0) {
                log.info("{}路徑的檔案不存在!!!", PACKET_CLASS);
                return Collections.unmodifiableList(registerClasses);
            }

            // 通過類名建立類
            for (Resource re : resources) {
                String fileName = re.getFilename();
                if (fileName == null)
                    continue;
                int classIndex = fileName.indexOf(CLASS_SUFFIX);
                fileName = fileName.substring(0, classIndex);
                String className = CLASS_PREFIX + fileName;
                // 類載入器建立類
                Class<?> cla = appClassLoader.loadClass(className);
                // 開啟訪問許可權，例項化
                Constructor<?> constr = cla.getConstructor();
                constr.setAccessible(true);
                registerClasses.add(cla.getConstructor().newInstance());
                total++;
            }
        } catch (Exception e) {
            log.error(e.getMessage());
        }
        long end = System.currentTimeMillis();
        log.info("成功查詢類檔案{}個,建立類{}個, 耗時{}ms", resources.length, total, (end - start) / 1000);
        return Collections.unmodifiableList(registerClasses);
    }
}

package com.cgx.logtest1;

import java.util.List;public class Logtest1Application {

    public static void main(String[] args) {
        BuildCla cla = new BuildCla();
        List<Object> cs = cla.searchAndBuild();
        for (Object obj : cs) {
            System.out.println(obj.toString());
        }
    }

}