java利用reflectasm反射 博客分类： Java reflectasmjava反射

import java.lang.reflect.Field;
import java.util.concurrent.ConcurrentMap;
import com.esotericsoftware.reflectasm.MethodAccess;
import com.google.common.collect.Maps;

public class ReflectUtil {
    private static final ConcurrentMap<Class<?>, MethodAccess> localCache = Maps.newConcurrentMap();

    private ReflectUtil() {

    }

    public static String upperFirstChar(String str) {
        if (str == null || "".equals(str)) {
            return str;
        }
        char[] cs = str.toCharArray();
        cs[0] -= 32;
        return String.valueOf(cs);
    }
    
    public static Object setProperty(Object clazz, String fname, Object fvalue) {
        if (clazz == null) {
            throw new IllegalArgumentException("No bean specified");
        }
        if (fname == null) {
            throw new IllegalArgumentException("No name specified for bean class '" + clazz.getClass() + "'");
        }
        return get(clazz.getClass()).invoke(clazz, "set" + upperFirstChar(fname), fvalue);
    }

    public static Object getProperty(Object clazz, String fname) {
        if (clazz == null) {
            throw new IllegalArgumentException("No bean specified");
        }
        if (fname == null) {
            throw new IllegalArgumentException("No name specified for bean class '" + clazz.getClass() + "'");
        }
        return get(clazz.getClass()).invoke(clazz, "get" + upperFirstChar(fname));
    }

    public static MethodAccess get(Class<?> clazz) {
        if (localCache.containsKey(clazz)) {
            return localCache.get(clazz);
        }

        MethodAccess methodAccess = MethodAccess.get(clazz);
        localCache.putIfAbsent(clazz, methodAccess);
        return methodAccess;
    }

    public static <F, T> void copyPropertiesIgnoreNull(F from, T to) {
        copyProperties(from, to, true);
    }

    public static <F, T> void copyProperties(F from, T to) {
        copyProperties(from, to, false);
    }

    public static <F, T> void copyProperties(F from, T to, boolean ignoreNull) {
        MethodAccess fromMethodAccess = get(from.getClass());
        MethodAccess toMethodAccess = get(to.getClass());
        Field[] fromDeclaredFields = from.getClass().getDeclaredFields();
        for (Field field : fromDeclaredFields) {
            String name = field.getName();
            try {
                Object value = fromMethodAccess.invoke(from, "get" + upperFirstChar(name));
                if (ignoreNull && value == null) {
                    continue;
                }
                toMethodAccess.invoke(to, "set" + upperFirstChar(name), value);
            } catch (Exception e) {
            }
        }
    }
}