描述
報錯以下
java.lang.IllegalArgumentException: URLDecoder: Illegal hex characters in escape (%) pattern - For input string: 「����」html
若是url中有%或者+會報上面的錯誤前端
這裏以%爲例：java
瀏覽器URL只能是英文、阿拉伯數字和標點符號，中文的話須要編碼解碼，瀏覽器遇到中文會自動的編碼爲%B2這樣的%加16進制的，但是%不會處理。apache
就像」你好啊%「，最終變成了」%B2%E2%CA%D4%B1%A8%B4%ED%「json
%在被編碼的時候變成了%25，咱們傳進來的url原本包括%的話，瀏覽器不會進行處理，仍是%，可是在解碼的時候，程序認爲%後面還應該有25，但是的的確確沒有這個25，解碼的程序不認識了，不知道怎麼解碼了，就拋出了異常java.lang.IllegalArgumentException瀏覽器
2019-11-4同類問題更新
Exception in thread 「main」 java.lang.IllegalArgumentException: URLDecoder: Illegal hex characters in escape (%) pattern - For input string: 「u8」app
後面是u8說明是中文的工具
解決
針對於For input string: "����"這種普通的
原來的解碼前加兩行代碼測試
val = val.replaceAll("%(?![0-9a-fA-F]{2})", "%25"); val = val.replaceAll("\\+", "%2B"); val = URLDecoder.decode(val, "utf-8");
針對於For input string: "u8"這種中文的
須要unescape 解碼
緣由分析：
java的StringEscapeUtils轉義與反轉義
這裏分析多是客戶傳遞的json字符串通過了Escape轉換爲了Unicode編碼（多是前端進行的轉化），因此須要轉回去（通常瀏覽器中有中文會自動轉換的，這種轉換成的經過decode不會報錯，可是unicode編碼這種是會報錯的）編碼
解決方式：
添加工具類
package demo; import org.apache.commons.lang3.StringEscapeUtils; public class Escape { private final static String[] hex = { "00","01","02","03","04","05","06","07","08","09","0A","0B","0C","0D","0E","0F", "10","11","12","13","14","15","16","17","18","19","1A","1B","1C","1D","1E","1F", "20","21","22","23","24","25","26","27","28","29","2A","2B","2C","2D","2E","2F", "30","31","32","33","34","35","36","37","38","39","3A","3B","3C","3D","3E","3F", "40","41","42","43","44","45","46","47","48","49","4A","4B","4C","4D","4E","4F", "50","51","52","53","54","55","56","57","58","59","5A","5B","5C","5D","5E","5F", "60","61","62","63","64","65","66","67","68","69","6A","6B","6C","6D","6E","6F", "70","71","72","73","74","75","76","77","78","79","7A","7B","7C","7D","7E","7F", "80","81","82","83","84","85","86","87","88","89","8A","8B","8C","8D","8E","8F", "90","91","92","93","94","95","96","97","98","99","9A","9B","9C","9D","9E","9F", "A0","A1","A2","A3","A4","A5","A6","A7","A8","A9","AA","AB","AC","AD","AE","AF", "B0","B1","B2","B3","B4","B5","B6","B7","B8","B9","BA","BB","BC","BD","BE","BF", "C0","C1","C2","C3","C4","C5","C6","C7","C8","C9","CA","CB","CC","CD","CE","CF", "D0","D1","D2","D3","D4","D5","D6","D7","D8","D9","DA","DB","DC","DD","DE","DF", "E0","E1","E2","E3","E4","E5","E6","E7","E8","E9","EA","EB","EC","ED","EE","EF", "F0","F1","F2","F3","F4","F5","F6","F7","F8","F9","FA","FB","FC","FD","FE","FF" }; private final static byte[] val = { 0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F, 0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F, 0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F, 0x00,0x01,0x02,0x03,0x04,0x05,0x06,0x07,0x08,0x09,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F, 0x3F,0x0A,0x0B,0x0C,0x0D,0x0E,0x0F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F, 0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F, 0x3F,0x0A,0x0B,0x0C,0x0D,0x0E,0x0F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F, 0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F, 0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F, 0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F, 0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F, 0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F, 0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F, 0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F, 0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F, 0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F,0x3F }; public static String escape(String s) { StringBuffer sbuf = new StringBuffer(); int len = s.length(); for (int i = 0; i < len; i++) { int ch = s.charAt(i); if (ch == ' ') { // space : map to '+' sbuf.append('+'); } else if ('A' <= ch && ch <= 'Z') { // 'A'..'Z' : as it was sbuf.append((char)ch); } else if ('a' <= ch && ch <= 'z') { // 'a'..'z' : as it was sbuf.append((char)ch); } else if ('0' <= ch && ch <= '9') { // '0'..'9' : as it was sbuf.append((char)ch); } else if (ch == '-' || ch == '_' // unreserved : as it was || ch == '.' || ch == '!' || ch == '~' || ch == '*' || ch == '/' || ch == '(' || ch == ')') { sbuf.append((char)ch); } else if (ch <= 0x007F) { // other ASCII : map to %XX sbuf.append('%'); sbuf.append(hex[ch]); } else { // unicode : map to %uXXXX sbuf.append('%'); sbuf.append('u'); sbuf.append(hex[(ch >>> 8)]); sbuf.append(hex[(0x00FF & ch)]); } } return sbuf.toString(); } public static String unescape(String s) { StringBuffer sbuf = new StringBuffer(); int i = 0; int len = s.length(); while (i < len) { int ch = s.charAt(i); if (ch == '+') { // + : map to ' ' sbuf.append(' '); } else if ('A' <= ch && ch <= 'Z') { // 'A'..'Z' : as it was sbuf.append((char)ch); } else if ('a' <= ch && ch <= 'z') { // 'a'..'z' : as it was sbuf.append((char)ch); } else if ('0' <= ch && ch <= '9') { // '0'..'9' : as it was sbuf.append((char)ch); } else if (ch == '-' || ch == '_' // unreserved : as it was || ch == '.' || ch == '!' || ch == '~' || ch == '*' || ch == '/' || ch == '(' || ch == ')') { sbuf.append((char)ch); } else if (ch == '%') { int cint = 0; if ('u' != s.charAt(i+1)) { // %XX : map to ascii(XX) cint = (cint << 4) | val[s.charAt(i+1)]; cint = (cint << 4) | val[s.charAt(i+2)]; i+=2; } else { // %uXXXX : map to unicode(XXXX) cint = (cint << 4) | val[s.charAt(i+2)]; cint = (cint << 4) | val[s.charAt(i+3)]; cint = (cint << 4) | val[s.charAt(i+4)]; cint = (cint << 4) | val[s.charAt(i+5)]; i+=5; } sbuf.append((char)cint); } i++; } return sbuf.toString(); } public static void main(String[] args) { String stest = "蘇州"; System.out.println(stest); System.out.println(escape(stest)); System.out.println(unescape("%u82CF%u5DDE")); } }
這裏的util類轉自URLDecoder失敗 感謝
整體解決方案
try { //這裏要替換的是單獨的%而不是所有的% val = val.replaceAll("%(?![0-9a-fA-F]{2})", "%25"); val = val.replaceAll("\\+", "%2B"); //解決中文的問題 val = EscapeUtil.unescape(val); val = URLDecoder.decode(val,"UTF-8"); } catch (IllegalArgumentException ex) { //未知的問題 log.warn("ParamProcessor exception --->", ex); }
Demo
package com.leesin; import java.io.UnsupportedEncodingException; import java.net.URLDecoder; import java.net.URLEncoder; public class DecodeTest { public static void main(String[] args) throws UnsupportedEncodingException { String testString = "測試沒有特殊字符的解碼"; String encode = URLEncoder.encode(testString, "gbk"); String decode = URLDecoder.decode(encode, "gbk"); System.out.println("沒有特殊字符解碼的--" + encode); System.out.println("沒有特殊字符解碼的--" + decode); String testString1 = "%測試有特殊字符的解碼"; String encode1 = URLEncoder.encode(testString1, "gbk"); String decode1 = URLDecoder.decode(encode1, "gbk"); System.out.println("有特殊字符解碼的--" + encode1); System.out.println("有特殊字符解碼的--" + decode1); String testString2 = "測試報錯%"; // String encode2 = URLEncoder.encode(testString2, "gbk"); String encode2 = "%B2%E2%CA%D4%B1%A8%B4%ED%"; String decode2 = URLDecoder.decode(encode2, "gbk"); System.out.println("有特殊字符解碼的--" + encode2); System.out.println("有特殊字符解碼的--" + decode2); } }
結果
感謝
java轉義問題【java.lang.IllegalArgumentException: URLDecoder: Incomplete trailing escape (%) pattern】