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AJAXJS aims to full-stack, not only the server-side framework,
but also integrates the front-end library. It's written in HTML5 + Java, a successor to the JVM platform, efficient, secure, stable, cross-platform and many other advantages, but it abandoned the traditional enterprise architecture brought about by the large and bloated,
emphasizing the lightweight, and fast, very suitable for the Internet fast application.
/**
* Copyright Sp42 [email protected]
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.ajaxjs.js;
import java.beans.IntrospectionException;
import java.beans.Introspector;
import java.beans.PropertyDescriptor;
import java.lang.reflect.Field;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Date;
import java.util.List;
import java.util.Map;
import java.util.function.Function;
import com.ajaxjs.framework.BaseModel;
import com.ajaxjs.js.jsonparser.syntax.FMS;
import com.ajaxjs.util.CommonUtil;
import com.ajaxjs.util.MapTool;
/**
* 序列化/反序列化 JSON
*
* @author Sp42 [email protected]
*/
public class JsonHelper {
/**
* 解析 JSON 为 Map 或 List
*
* @param str JSON 字符串
* @return Map 或 List
*/
public static Object parse(String str) {
return new FMS(str).parse();
}
/**
* 解析 JSON 字符串为 Map
*
* @param str JSON 字符串
* @return Map
*/
@SuppressWarnings("unchecked")
public static Map parseMap(String str) {
return (Map) parse(str);
}
/**
* 解析 JSON 字符串为 List
*
* @param str 字符串
* @return List
*/
@SuppressWarnings("unchecked")
public static List> parseList(String str) {
return (List>) parse(str);
}
/**
* 对 Object 尝试类型检测，将其合适地转换为 JSON 字符串返回。
*
* @param obj 任意对象
* @return JSON 字符串
*/
public static String toJson(Object obj) {
if (obj == null) {
return null;
} else if (obj instanceof Boolean || obj instanceof Number) {
return obj.toString();
} else if (obj instanceof String) {
return '\"' + obj.toString().replace("\\", "\\\\").replace("\"", "\\\"").replace("\n", "\\n").replace("\r", "\\r") + '\"';
} else if (obj instanceof String[]) {
return jsonArr((String[]) obj, v -> "\"" + v + "\"");
} else if (obj.getClass() == Integer[].class) {
return jsonArr((Integer[]) obj, v -> v + "");
} else if (obj.getClass() == int[].class) {
Integer[] arr = Arrays.stream((int[]) obj).boxed().toArray(Integer[]::new);
return jsonArr(arr, v -> v + "");
} else if (obj instanceof Long[]) {
return jsonArr((Long[]) obj, v -> v.toString());
} else if (obj instanceof long[]) {
Long[] arr = Arrays.stream((long[]) obj).boxed().toArray(Long[]::new);
return jsonArr(arr, v -> v.toString());
} else if (obj instanceof Date) {
return '\"' + CommonUtil.SimpleDateFormatFactory(CommonUtil.commonDateFormat).format((Date) obj) + '\"';
} else if (obj instanceof Map) {
return stringifyMap((Map) obj);
} else if (obj instanceof Map[]) {
return jsonArr((Map[]) obj, JsonHelper::stringifyMap);
} else if (obj instanceof BaseModel) {
return beanToJson((BaseModel) obj);
} else if (obj instanceof BaseModel[]) {
return jsonArr((BaseModel[]) obj, JsonHelper::beanToJson);
} else if (obj instanceof List) {
List list = (List) obj;
if (list.size() > 0) {
if (list.get(0) instanceof Integer) {
return toJson(list.toArray(new Integer[list.size()]));
} else if (list.get(0) instanceof String) {
return toJson(list.toArray(new String[list.size()]));
} else if (list.get(0) instanceof Map) { // Map 类型的输出
return toJson(list.toArray(new Map[list.size()]));
} else if (list.get(0) instanceof BaseModel) { // Bean
return toJson(list.toArray(new BaseModel[list.size()]));
}
} else {
return "[]";
}
} else if (obj instanceof Object[]) {
return jsonArr((Object[]) obj, JsonHelper::toJson);
} else if (obj instanceof Object) { // 普通 Java Object
List arr = new ArrayList<>();
for (Field field : obj.getClass().getDeclaredFields()) {
field.setAccessible(true);
String key = field.getName();
if (key.indexOf("this$") != -1)
continue;
Object _obj = null;
try {
_obj = field.get(obj);
} catch (IllegalAccessException e) {
e.printStackTrace();
}
arr.add('\"' + key + "\":" + toJson(_obj));
}
return '{' + String.join(",", arr) + '}';
}
return null;
}
/**
* 输入任意类型数组，在 fn 作适当的转换，返回 JSON 字符串
*
* @param o 数组
* @param fn 元素处理器，返回元素 JSON 字符串
* @return 数组的 JSON 字符串
*/
public static String jsonArr(T[] o, Function fn) {
if (o.length == 0)
return "[]";
StringBuilder sb = new StringBuilder();
for (int i = 0; i < o.length; i++) {
sb.append(fn.apply((T) o[i]));
if (i != (o.length - 1))
sb.append(", ");
}
return '[' + sb.toString() + ']';
}
/**
*
* @param list
* @param fn 元素处理器，返回元素 JSON 字符串
* @return
*/
static String eachList(List list, Function fn) {
StringBuilder sb = new StringBuilder();
for (int i = 0; i < list.size(); i++) {
sb.append(fn.apply(list.get(i)));
if (i != (list.size() - 1))
sb.append(", ");
}
return '[' + sb.toString() + ']';
}
/**
* 输入一个 Map，将其转换为 JSON Str
*
* @param map 输入数据
* @return JSON 字符串
*/
public static String stringifyMap(Map map) {
if (map == null)
return null;
if (map.size() == 0)
return "{}";
List arr = new ArrayList<>();
for (Object key : map.keySet())
arr.add('\"' + key.toString() + "\":" + toJson(map.get(key)));
return '{' + String.join(",", arr) + '}';
}
/**
* Bean 转换为 JSON 字符串
*
* 传入任意一个 Java Bean 对象生成一个指定规格的字符串
*
* @param bean bean对象
* @return String "{}"
*/
public static String beanToJson(Object bean) {
StringBuilder json = new StringBuilder();
json.append("{");
PropertyDescriptor[] props = null;
try {
props = Introspector.getBeanInfo(bean.getClass(), Object.class).getPropertyDescriptors();
} catch (IntrospectionException e) {
e.printStackTrace();
}
if (props != null) {
for (int i = 0; i < props.length; i++) {
try {
String name = "\"" + props[i].getName() + "\"";
String value = toJson(props[i].getReadMethod().invoke(bean));
json.append(name);
json.append(":");
json.append(value);
json.append(",");
} catch (Exception e) {
e.printStackTrace();
}
}
json.setCharAt(json.length() - 1, '}');
} else {
json.append("}");
}
return json.toString();
}
/**
* JSON 字符串转换为 Bean 对象
*
* @param json JSON 字符串
* @param clz Bean 对象类引用
* @return Bean 对象
*/
public static T json2bean(String json, Class clz) {
Map map = parseMap(json);
return MapTool.map2Bean(map, clz, true);
}
/**
* 格式化 JSON，使其美观输出到控制或其他地方 请注意 对于json中原有\n \t 的情况未做过多考虑 得到格式化json数据 退格用\t 换行用\r
*
* @param json 原 JSON 字符串
* @return 格式化后美观的 JSON
*/
public static String format(String json) {
int level = 0;
StringBuilder str = new StringBuilder();
for (int i = 0; i < json.length(); i++) {
char c = json.charAt(i);
if (level > 0 && '\n' == str.charAt(str.length() - 1))
str.append(CommonUtil.repeatStr("\t", "", level));
switch (c) {
case '{':
case '[':
str.append(c + "\n");
level++;
break;
case ',':
if (json.charAt(i + 1) == '"')
str.append(c + "\n"); // 后面必定是跟着 key 的双引号，但 其实 json 可以 key 不带双引号的
break;
case '}':
case ']':
str.append("\n");
level--;
str.append(CommonUtil.repeatStr("\t", "", level));
str.append(c);
break;
default:
str.append(c);
break;
}
}
return str.toString();
}
/**
* 删除 JSON 注释
*
* @param str 待处理的字符串
* @return 删除注释后的字符串
*/
public static String removeComemnt(String str) {
return str.replaceAll("\\/\\/[^\\n]*|\\/\\*([^\\*^\\/]*|[\\*^\\/*]*|[^\\**\\/]*)*\\*+\\/", "");
}
/**
* 输出到 JSON 文本时候的换行
*
* @param str JSON 字符串
* @return
*/
public static String jsonString_covernt(String str) {
return str.replace("\r\n", "\\n");
}
/**
*
* @param str JSON 字符串
* @return
*/
public static String javaValue2jsonValue(String str) {
return str.replaceAll("\"", "\\\\\"").replaceAll("\t", "\\\\\t");
}
}