自己通过反射写的一个属性copy类
package com.xxx.beancopier; import java.lang.annotation.Documented; import java.lang.annotation.ElementType; import java.lang.annotation.Retention; import java.lang.annotation.RetentionPolicy; import java.lang.annotation.Target; import java.lang.reflect.Method; import java.lang.reflect.Modifier; /** * @Type BeanCopier * @Desc 属性copy类 * @author * @date 2017-01-06 * @Version V1.0 */ public class BeanCopier { private BeanCopier() { } public static <DestType> DestType propertiesCopy(Object orig, DestType dest) { if (orig == null || dest == null) { throw new RuntimeException("参数不能为null"); } Method[] destMethods = dest.getClass().getMethods(); for (Method destMethod : destMethods) { if (needCopy(destMethod)) { MethodCopy methodCopy = new MethodCopy(destMethod); methodCopy.copy(orig, dest); } } return dest; } private static boolean needCopy(Method method) { PropertyCopy annotation = method.getAnnotation(PropertyCopy.class); if (annotation != null && annotation.ignore()) return false; return method.getName().startsWith("set") && method.getParameterTypes().length == 1 && Modifier.isPublic(method.getModifiers()) && !Modifier.isStatic(method.getModifiers()); } static class MethodCopy { private Method method; private String methodName; private Method getterMethod; public MethodCopy(Method destMethod) { method = destMethod; methodName = destMethod.getName(); } private void copy(Object orig, Object dest) { try { this.getterMethod = orig.getClass().getMethod("get" + methodName.substring(3)); } catch (NoSuchMethodException e) { throw new RuntimeException("对象【" + orig + "】中缺失【" + methodName.replaceFirst("set", "get") + "()】方法!"); } Object propertyValue = invokeMethod(orig, getterMethod); if (propertyValue != null) { invokeMethod(dest, method, propertyValue); } } private Object invokeMethod(Object targerObject, Method method, Object... args) { if (method == null) { throw new RuntimeException("被调用方法不能为空!"); } // 验证参数数量 Class<?>[] parameterTypes = method.getParameterTypes(); if (parameterTypes.length != args.length) { throw new RuntimeException("方法【" + method + "】的参数数量【" + parameterTypes.length + "】和反射调用时的参数数量【" + args.length + "】不相符,无法完成调用!"); } try { method.setAccessible(true); return method.invoke(targerObject, args); } catch (Throwable e) { throw new RuntimeException("调用对象【" + targerObject + "】的【" + method + "】方法,参数为【" + args + "】时发生异常:", e); } } } } @Retention(RetentionPolicy.RUNTIME) @Target({ ElementType.METHOD }) @Documented @interface PropertyCopy { /** * 被标注方法是否被忽略拷贝 * @return */ boolean ignore() default false; }
使用如下:
StudentDTO studentDTO1 = BeanCopier.propertiesCopy(student, new StudentDTO());