高性能的BeanUtils（cglib版本）

「爱情、让人受尽委屈。」 2023-02-09 13:25 22阅读 0赞

> 不多说，直接上代码

import lombok.experimental.Accessors;
    import org.springframework.cglib.beans.BeanCopier;
    
    import java.io.Serializable;
    import java.util.concurrent.ConcurrentHashMap;
    
    /**
     * @author：Lee
     * @date： 2020/2/19
     * @description：注意，当复制和被复制任意一个对象包含了@Accessors(chain = true)注解不能使用该copy，可以使用spring的BeanUtils.copy
     */
    public class BeanUtils {
    
        private static ConcurrentHashMap<BeanCopierKey, BeanCopier> map = new ConcurrentHashMap<BeanCopierKey, BeanCopier>();
    
        public static <T extends Serializable> T copy(Object obj, Class<T> targetClazz) {
            T t = null;
            if (obj == null || targetClazz == null) {
                return t;
            }
            Class<?> srcType = obj.getClass();
            BeanCopierKey key = new BeanCopierKey(srcType, targetClazz);
            BeanCopier copier = map.get(key);
            if (copier == null) {
                map.putIfAbsent(key, BeanCopier.create(srcType, targetClazz, false));
                copier = map.get(key);
            }
            try {
                t = targetClazz.newInstance();
                copier.copy(obj, t, null);
            }
            catch (Exception e) {
                System.out.println("Bean对象复制失败: " + key);
            }
            return t;
        }
    
        static class BeanCopierKey {
    
            Class<?> srcType;
            Class<?> targetType;
    
            public BeanCopierKey(Class<?> srcType, Class<?> targetType) {
                this.srcType = srcType;
                this.targetType = targetType;
            }
    
            @Override
            public boolean equals(Object obj) {
                if (obj == null || !(obj instanceof BeanCopierKey)) {
                    return false;
                }
                BeanCopierKey key = (BeanCopierKey)obj;
                return key.srcType == srcType && key.targetType == targetType;
            }
    
            @Override
            public int hashCode() {
                return srcType.hashCode() + targetType.hashCode();
            }
    
            @Override
            public String toString() {
                return srcType + " -> " + targetType;
            }
    
        }
    }