com.bell.mf.mapper.Mapper Maven / Gradle / Ivy
package com.bell.mf.mapper;
import java.lang.reflect.Field;
import java.util.Arrays;
import java.util.List;
import org.springframework.util.StringUtils;
import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.JSONObject;
/**
* @ClassName Mapper
* @Description 映射工具
* @author bell.zhouxiaobing
* @date 2019年11月28日
* @since 1.4.0
*/
public class Mapper {
/**
* @Description 根据targetClass字段上标注的@MFMapperField注解解析body字符串
* @param body
* @param targetClass
* @return
* @throws IllegalAccessException
* @throws InstantiationException
*/
public static T mapper(final String body, Class targetClass) throws InstantiationException, IllegalAccessException {
// init size
MapperField[] bodyFields = new MapperField[targetClass.getDeclaredFields().length];
// 遍历所有字段，判断是否有标注@MapperField注解
for (Field field : targetClass.getDeclaredFields()) {
com.bell.mf.annotation.MapperField annotation = field.getAnnotation(com.bell.mf.annotation.MapperField.class);
if (annotation != null) {
MapperField mapperField = MapperField.builder().length(annotation.length())
.name(field.getName()).postHandler(getPostHandler(annotation)).build();
if (bodyFields[annotation.index()] != null) {
throw new RuntimeException(String.format("[%s#%s] @MapperField index [%s] duplicate", targetClass.getName(), field.getName(), annotation.index()));
}
bodyFields[annotation.index()] = mapperField;
}
}
JSONObject mapper = mapper(body, Arrays.asList(bodyFields));
if (mapper == null) { return null; }
return JSON.parseObject(mapper.toJSONString(), targetClass);
}
private static MapperFieldHandler getPostHandler(com.bell.mf.annotation.MapperField annotation) throws InstantiationException, IllegalAccessException {
if (annotation.postHandle() == MapperFieldHandler.class) {
return annotation.anonymousMethod().getPostHandler();
}
return annotation.postHandle().newInstance();
}
/**
* @Description 根据MapperField的list集合解析body字符串
* @param body
* @param list
* @return
*/
public static JSONObject mapper(final String body, List list) {
if (StringUtils.isEmpty(body) || list.isEmpty())
return null;
JSONObject result = new JSONObject(list.size());
int start = 0;
for (int i = 0; i < list.size(); i++) {
MapperField field = list.get(i);
String val = body.substring(start, start + field.getLength());
result.put(field.getName(), val);
start += field.getLength();
}
// postHandle
for (int i = 0; i < list.size(); i++) {
MapperField field = list.get(i);
MapperFieldHandler handler = field.getPostHandler();
if (handler != null) {
String key = field.getName();
String val = (String) result.get(key);
result.put(key, handler.postHandle(val, result));
}
}
return result;
}
}