自己写的json转java bean工具类

前言

用json-lib自带的toBean感觉不太好用，对于复杂的嵌套会报错，会报错：MorphDynaBean cannot be cast to ** 故自己尝试写一下。

记录

对Date、short类型的转换存在问题，暂时不管了

代码

public static <T> T json2Bean(JSONObject json, Class<T> clazz) throws Exception {
T t = clazz.newInstance();
Method[] methods = clazz.getDeclaredMethods();
if (methods == null || methods.length == 0)
return null;

for (Method method : methods) {
String methodName = method.getName();
if (methodName.startsWith("set")) {
StringBuffer fieldName = new StringBuffer();

// 形参类型：String long Product boolean double short int String List
Class<?> ParamClazz = method.getParameterTypes()[0];

// 通过set的method拿到字段名称name time delFlag birth price price2 age
fieldName.append(methodName.substring(3, 4).toLowerCase())// 字段首字母小写
.append(methodName.substring(4));

if (!json.has(fieldName.toString())) {
continue;
}

// 常用基本类型 不含short,Date(支持String类型的 日期)
if (ParamClazz == boolean.class || ParamClazz == Boolean.class) {
method.invoke(t, new Object[] { json.optBoolean(fieldName.toString(), false) });
} else if (ParamClazz == int.class || ParamClazz == Integer.class) {
method.invoke(t, new Object[] { json.optInt(fieldName.toString(), 0) });
} else if (ParamClazz == long.class || ParamClazz == Long.class) {
method.invoke(t, new Object[] { json.optLong(fieldName.toString(), 0) });
} else if (ParamClazz == double.class || ParamClazz == Double.class) {
method.invoke(t, new Object[] { json.optDouble(fieldName.toString(), 0) });
} else if (ParamClazz == String.class) {
method.invoke(t, new Object[] { json.optString(fieldName.toString(), "") });
}else if(ParamClazz == Date.class){
method.invoke(t, new Object[] { json.optString(fieldName.toString(),"") });
}else if (List.class.isAssignableFrom(ParamClazz)) {//解析jsonArray为list
JSONArray array = json.getJSONArray(fieldName.toString());
List list = new ArrayList<>();
for(int i =0;array!=null && i<array.size();i++){
JSONObject jsonobj = array.getJSONObject(i);

Class<?> listType = (Class<?>) ((ParameterizedType) clazz   // 获取List的泛型类型
.getDeclaredField(fieldName.toString()).getGenericType())
.getActualTypeArguments()[0];

Object obj = json2Bean(jsonobj, listType);
list.add(obj);
}
method.invoke(t,list);

} else {//jsonObject和无法解析字段的判断
try{
JSONObject getjsonObj = json.getJSONObject(fieldName.toString());
Object obj = json2Bean(getjsonObj, ParamClazz);
method.invoke(t, obj);
}catch(JSONException e){
e.printStackTrace();
continue;
}
}
}
}
return t;
}