package com.mazhichu.util;

import lombok.Data;

import java.lang.reflect.Field;
import java.lang.reflect.Method;

/**
 * <p class="detail">
 * 功能: 去掉字符串类型的首尾空格
 * </p>
 *
 * @author Moore
 * @ClassName Bean value trim util.
 * @Version V1.0.
 * @date 2019.11.29 15:53:44
 */
public class BeanValueTrimUtil {
     /**
      * 去掉bean中所有属性为字符串的前后空格
      * @param bean
      * @throws Exception
      */
     public static void beanValueTrim(Object bean) throws Exception {
         if(bean!=null){
             //获取所有的字段包括public,private,protected,private
             Field[] fields = bean.getClass().getDeclaredFields();
             for (int i = 0; i < fields.length; i++) {
                 Field f = fields[i];
                 if (f.getType().getName().equals("java.lang.String")) {
                     String key = f.getName();//获取字段名
                     Object value = getFieldValue(bean, key);

                     if (value == null)
                         continue;

                     setFieldValue(bean, key, value.toString().trim());
                 }
             }
         }
     }

     /**
      * 利用反射通过get方法获取bean中字段fieldName的值
      * @param bean
      * @param fieldName
      * @return
      * @throws Exception
      */
     private static Object getFieldValue(Object bean, String fieldName)
             throws Exception {
         StringBuffer result = new StringBuffer();
         String methodName = result.append("get")
                 .append(fieldName.substring(0, 1).toUpperCase())
                 .append(fieldName.substring(1)).toString();

         Object rObject = null;
         Method method = null;

         @SuppressWarnings("rawtypes")
         Class[] classArr = new Class[0];
         method = bean.getClass().getMethod(methodName, classArr);
         rObject = method.invoke(bean, new Object[0]);

         return rObject;
     }

     /**
      * 利用发射调用bean.set方法将value设置到字段
      * @param bean
      * @param fieldName
      * @param value
      * @throws Exception
      */
     private static void setFieldValue(Object bean, String fieldName, Object value)
             throws Exception {
         StringBuffer result = new StringBuffer();
         String methodName = result.append("set")
                 .append(fieldName.substring(0, 1).toUpperCase())
                 .append(fieldName.substring(1)).toString();

         /**
          * 利用发射调用bean.set方法将value设置到字段
          */
         Class[] classArr = new Class[1];
         classArr[0]="java.lang.String".getClass();
         Method method=bean.getClass().getMethod(methodName,classArr);
         method.invoke(bean,value);
     }

     @Data
     public static class User{
         private String username;
         private String password;
         private int age;
     }

    public static void main(String[] args) throws Exception {
         User user = new User();
         user.setUsername(" hehe ");
         user.setPassword(" ha ha");
         user.setAge(12);
         beanValueTrim(user);
    }
 }