JAVA校验JSON数据格式「建议收藏」

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在此博文基础上增添了更多校验功能https://blog.csdn.net/weixin_42540829/article/details/88326880

   public static final class RouteTableJsonValidator {
/**
* 数组指针
*/
private static int index;
/**
* 字符串
*/
private static String value;
/**
* 指针当前字符
*/
private static char curchar;
/**
* 工具类非公有构造函数
*/
private RouteTableJsonValidator() {
}
/**
* @param rawValue 字符串参数
* @return boolean 是否是JSON
*/
public static boolean isJSON(String rawValue) throws Exception {
index = 0;
value = rawValue;
switch (nextClean()) {
case '[':
if (nextClean() == ']') {
return true;
}
back();
return validateArray();
case '{':
if (nextClean() == '}') {
return true;
}
back();
return validateObject();
default:
return false;
}
}
/**
* @return char 下一个有效实义字符 char<=' ' char!=127
* @throws JSONException 自定义JSON异常
*/
public static char nextClean() throws JSONException {
skipComment:
do {
next();
if (curchar == '/') { // 跳过//类型与/*类型注释 遇回车或者null为注释内容结束
switch (next()) {
case 47: // '/'
do {
curchar = next();
} while (curchar != '\n' && curchar != '\r' && curchar != 0);
continue;
case 42: // '*'
do {
do {
next();
if (curchar == 0) {
throw syntaxError("Unclosed comment");
}
} while (curchar != '*');
if (next() == '/') {
continue skipComment;
}
back();
} while (true);
}
back();
return '/';
}
if (curchar != '#') { //跳过#类型注释 遇回车或者null为注释内容结束
break;
}
do {
next();
} while (curchar != '\n' && curchar != '\r' && curchar != 0);
} while (true);
if (curchar != 0 && (curchar <= ' ' || curchar == 127)) {
throw syntaxError("JSON can not contain control character!");
}
return curchar;
}
/**
* @return char 下一个字符
*/
public static char next() {
if (index < 0 || index >= value.length()) {
return '\0';
}
curchar = value.charAt(index);
if (curchar <= 0) {
return '\0';
} else {
index++;
return curchar;
}
}
/**
* 将指针移至上一个字符，回退一位
*/
public static void back() { //异常在next中进行返回null
index--;
}
/**
* @param message 异常自定义信息
* @return JSONException 自定义JSON异常
*/
public static JSONException syntaxError(String message) {
return new JSONException((new StringBuilder(String.valueOf(message))).toString());
}
/**
* @return boolean 是否是JSONArray
* @throws JSONException 自定义JSON异常
*/
public static boolean validateArray() throws JSONException {
do {
//入口为合法 [ array 起点
nextClean(); //下一位有效字符，跳过注释
if (curchar == ']') { //空array 直接闭合返回
return true;
} else if (curchar == ',') { //null
continue;
} else if (curchar == '"') { //String
validateString();
} else if (curchar == '-' || (curchar >= 48 && curchar <= 57)) { // number
validateNumber();
} else if (curchar == '{') { // object
if (!validateObject()) { //递归校验
return false;
}
} else if (curchar == '[') { // array
if (!validateArray()) { //递归校验
return false;
}
} else if (curchar == 't' || curchar == 'f' || curchar == 'n') { // boolean and JSONNull
validateBooleanAndNull();
} else {
return false;
}
switch (nextClean()) {
case ',':
continue;
case ']':
return true;
default:
return false;
}
} while (true);
}
/**
* @return boolean 是否是JSONObject
* @throws JSONException 自定义JSON异常
*/
public static boolean validateObject() throws JSONException {
do {
nextClean();
if (curchar == '}') {
return true;
} else if (curchar == '"') { //String
validateString();
} else {
return false;
}
if (nextClean() != ':') {
return false;
}
nextClean();
if (curchar == ',') { //null
throw syntaxError("Missing value");
} else if (curchar == '"') { //String
validateString();
} else if (curchar == '-' || (curchar >= 48 && curchar <= 57)) { // number
validateNumber();
} else if (curchar == '{') { // object
if (!validateObject()) {
return false;
}
} else if (curchar == '[') { // array
if (!validateArray()) {
return false;
}
} else if (curchar == 't' || curchar == 'f' || curchar == 'n') { // boolean and JSONNull
validateBooleanAndNull();
} else {
return false;
}
switch (nextClean()) {
case ',':
continue;
case '}':
return true;
default:
return false;
}
} while (true);
}
/**
* @throws JSONException 自定义JSON异常
*/
public static void validateString() throws JSONException {
StringBuilder sb = new StringBuilder();
do {
curchar = next(); //JSON对字符串中的转义项有严格规定
sb.append(curchar);
if (curchar == '\\') {
if ("\"\\/bfnrtu".indexOf(next()) < 0) {
throw syntaxError("Invalid escape string");
}
if (curchar == 'u') { //校验unicode格式 后跟4位16进制 0-9 a-f A-F
for (int i = 0; i < 4; i++) {
next();
if (curchar < 48 || (curchar > 57 && curchar < 65) || (curchar > 70 && curchar < 97)
|| curchar > 102) {
throw syntaxError("Invalid hexadecimal digits");
}
}
}
}
} while (curchar >= ' ' && "\":{[,#/".indexOf(curchar)< 0 && curchar != 127);
if (curchar == 0) { //仅正常闭合双引号可通过
throw syntaxError("Unclosed quot");
} else if (curchar != '"') {
throw syntaxError("Invalid string {\""+ sb +"}, missing quot ");
} else if (value.charAt(index)=='"') {
throw syntaxError("Missing comma after string: \"" + sb);
} else if (value.charAt(index)==':' ) {
String str = sb.substring(0, sb.length() - 1);
//                if (!validateRouteTableKey(sb.charAt(0), str)) {
//                    throw syntaxError("Invalid RouteTable KEY:\"" + sb);
//                }
validateRouteTableValue(str);
}
}
/**
* @throws JSONException 自定义JSON异常
*/
public static void validateNumber() throws JSONException {
StringBuilder sb = new StringBuilder();
if (curchar == '-') { //可选负号
curchar = next();
}
if (curchar > 48 && curchar <= 57) { //整数部分
do {
sb.append(curchar);
curchar = next();
} while (curchar >= 48 && curchar <= 57);
} else if (curchar == 48) {
curchar = next();
} else {
throw syntaxError("Invalid number");
}
if (curchar == '.') { //小数部分
do { //.后可不跟数字 如 5. 为合法数字
curchar = next();
} while (curchar >= 48 && curchar <= 57);
}
if (curchar == 'e' || curchar == 'E') { //科学计数部分
curchar = next();
if (curchar == '+' || curchar == '-') {
curchar = next();
}
if (curchar < 48 || curchar > 57) {
throw syntaxError("Invalid number");
}
do {
curchar = next();
} while (curchar >= 48 && curchar <= 57);
}
if (curchar == '"') {
throw syntaxError("Missing comma after number: " + sb);
}
back(); //指针移至数字值最后一位，取下一位即判断是,或者],或者是合法注释
}
public static void validateRouteTableValue(String key) throws JSONException {
int a = index;
char c,d ;
List<String> num_list = Arrays.asList("port");
List<String> boolean_list = Arrays.asList("useSSL", "default_allow");
do {
++a;
c = value.charAt(a);
} while (c == ' ' || c == '"');
StringBuilder sb = new StringBuilder();
do {
d = value.charAt(a);
sb.append(d);
a++;
} while (d !=' ' && ",]}\"".indexOf(d) <0);
String str = sb.substring(0,sb.length()-1);
if (num_list.contains(key) && !(c == '-' || (c >= 48 && c <= 57))) {
throw syntaxError("RouteTable KEY:" + key + " match NumberType");
}
if (boolean_list.contains(key) && !(c == 't' || c == 'f' || c == 'n')) {
throw syntaxError("RouteTable KEY:" + key + " match BooleanType");
}
String port_reg = "^([0-5]?\\d{0,4}|6[0-4]\\d{3}|65[0-4]\\d{2}|655[0-2]\\d|6553[0-5])$";
if("port".equals(key) && !str.matches(port_reg)){
throw syntaxError("Invalid Port : " + str);
}
String ip_reg = "^(25[0-5]|2[0-4]\\d|[0-1]?\\d?\\d)(\\.(25[0-5]|2[0-4]\\d|[0-1]?\\d?\\d)){3}$";
if("ip".equals(key) && !str.matches(ip_reg)){
throw syntaxError("Invalid ip : " + str);
}
}
public static boolean validateRouteTableKey(char firstChar, String str) throws JSONException {
if ("".equals(str)) return false;
List<String> a_list = Arrays.asList("allow");
List<String> c_list = Arrays.asList("certChainFile","caFile","coordinator");
List<String> d_list = Arrays.asList("default", "default_allow","deny");
List<String> f_list = Arrays.asList("from");
List<String> h_list = Arrays.asList("host");
List<String> i_list = Arrays.asList("ip");
List<String> n_list = Arrays.asList("negotiationType","caFile");
List<String> p_list = Arrays.asList("permission", "port", "privateKeyFile");
List<String> r_list = Arrays.asList("route_table","role");
List<String> s_list = Arrays.asList("serving");
List<String> t_list = Arrays.asList("to");
List<String> u_list = Arrays.asList("useSSL");
switch (firstChar) {
case ' ':
return false;
case 'a':
return a_list.contains(str);
case 'f':
return f_list.contains(str);
case 't':
return t_list.contains(str);
case 'i':
return i_list.contains(str);
case 'h':
return h_list.contains(str);
case 's':
return s_list.contains(str);
case 'u':
return u_list.contains(str);
case 'c':
return c_list.contains(str);
case 'n':
return n_list.contains(str);
case 'r':
return r_list.contains(str);
case 'd':
return d_list.contains(str);
case 'p':
return p_list.contains(str);
default:
return true;
}
}
/**
* @throws JSONException 自定义JSON异常
*/
public static void validateBooleanAndNull() throws JSONException {
StringBuilder sb = new StringBuilder();
do {
sb.append(curchar);
curchar = next();
} while (curchar >= ' ' && "\",]#/}".indexOf(curchar) < 0 && curchar != 127);
if (!"null".equals(sb.toString()) && !"true".equals(sb.toString()) && !"false".equals(sb.toString())) {
throw syntaxError("Boolean/null spelling errors : " + sb);
}
if (curchar == '"') {
throw syntaxError("Missing comma after Boolean: " + sb);
}
back();
}
}
public static void main(String[] args) {
//        String str = "{\"route_table\": {\"default\":{\"default\":[{\"ip\":\"127.0.0.1\",\"port\":9999,\"useSSL\":false}]},\"10000\":{\"default\":[{\"ip\":\"127.0.0.1\",\"port\":8889}],\"serving\":[{\"ip\":\"127.0.0.1\",\"port\":8080}]},\"123\":[{\"host\":\"10.35.27.23\",\"port\":8888,\"useSSL\":false,\"negotiationType\":\"\",\"certChainFile\":\"\",\"privateKeyFile\":\"\",\"caFile\":\"\"}]},\"permission\":{\"default_allow\":true}}";
String str = "{\"route_table\":{\"default\":{\"default\":[{\"ip\":\"127.0.0.1\",\"port\":2345}]},\"10000\":{\"default\":[{\"ip\":\"127.0.0.1\",\"port\":8889}],\"serving\":[{\"ip\":\"127.0.0.1\",\"port\":8080}]}},\"permission\":{\"default_allow\":true,\"allow\":[{\"from\":{\"coordinator\":\"9999\",\"role\":\"guest\"},\"to\":{\"coordinator\":\"10000\",\"role\":\"host\"}}],\"deny\":[{\"from\":{\"coordinator\":\"9999\",\"role\":\"guest\"},\"to\":{\"coordinator\":\"10000\",\"role\":\"host\"}}]}}";
try {
if (RouteTableJsonValidator.isJSON(str)) {
String s = JsonUtil.formatJson(str);
System.out.println(s);
}
} catch (Exception e) {
System.out.println(e.getMessage());
}
}

Jetbrains全家桶1年46，售后保障稳定