首页 > 代码库 > java 使用反射转换对象 Object to Map
java 使用反射转换对象 Object to Map
Object to Map 转换的三种方法
就是把对象以及其对应的属性名 和属性值, 映射到一个Map中
import java.beans.BeanInfo; import java.beans.IntrospectionException; import java.beans.Introspector; import java.beans.PropertyDescriptor; import java.lang.reflect.Field; import java.lang.reflect.InvocationTargetException; import java.lang.reflect.Method; import java.util.HashMap; import java.util.Map; /** * User: pengfei.hpf * Date: 14-5-8 * Time: 下午12:34 */ public class ObjectToMap { public static void main(String[] args) throws IntrospectionException, InvocationTargetException, IllegalAccessException { TestObject o = new TestObject(); o.setCity("beijing"); o.setName("bj"); o.setOrder("ASC"); ObjectToMap objectToMap = new ObjectToMap(); System.out.println("=========== Invoke objectToMapViaBeanInfo ==========="); objectToMap.objectToMapViaBeanInfo(o); System.out.println("=========== Invoke objectToMapViaFields ==========="); objectToMap.objectToMapViaFields(o); System.out.println("=========== Invoke objectToMapViaApacheTools ==========="); objectToMapViaApacheTools(o); } /** * 通过Introspector 的方式复制属性值 * */ private static void objectToMapViaBeanInfo(TestObject o) throws IntrospectionException, InvocationTargetException, IllegalAccessException { Map<String, Object> result = new HashMap<String, Object>(); BeanInfo info = Introspector.getBeanInfo(o.getClass()); for (PropertyDescriptor pd : info.getPropertyDescriptors()) { Method reader = pd.getReadMethod(); //内容为null的过滤掉 if (reader == null || reader.invoke(o) == null) { continue; } //默认继承Object类的属性,过滤掉 if (pd.getName().equalsIgnoreCase("class")) { continue; } result.put(pd.getName(), reader.invoke(o)); } for (String key : result.keySet()) { System.out.println("Key:" + key + ";Value:" + result.get(key)); } } /** * 通过getDeclaredFields 的方式复制属性值 * getDeclaredFields方式不会返回父类的属性 * */ private static void objectToMapViaFields(TestObject o) throws IllegalAccessException { Map<String, Object> resMap = new HashMap<String, Object>(); Field[] declaredFields = o.getClass().getDeclaredFields(); for (Field field : declaredFields) { field.setAccessible(true); //过滤内容为空的 if (field.get(o) == null) { continue; } resMap.put(field.getName(), field.get(o)); } printOut(resMap); } /** * 通过Apache beanUtils的方式复制属性值 * 其内部实现方式同 方法1 * */ private static void objectToMapViaApacheTools(TestObject o) { Map<String, Object> resMap = new org.apache.commons.beanutils.BeanMap(o); printOut(resMap); } /** * 打印结果 * */ private static void printOut(Map<String, Object> resMap) { for (String key : resMap.keySet()) { System.out.println("Key:" + key + ";Value:" + resMap.get(key)); } } /** * 测试类 * */ public static class TestObject { String city; String name; String order; public String getOrder() { return order; } public void setOrder(String order) { this.order = order; } public String getName() { return name; } public void setName(String name) { this.name = name;
} public String getCity() { return city; } public void setCity(String city) { this.city = city; } } }
声明:以上内容来自用户投稿及互联网公开渠道收集整理发布,本网站不拥有所有权,未作人工编辑处理,也不承担相关法律责任,若内容有误或涉及侵权可进行投诉: 投诉/举报 工作人员会在5个工作日内联系你,一经查实,本站将立刻删除涉嫌侵权内容。