How to avoid special character from URL using java

Question

I am using below code to eliminate the special characters from URL:

String url1 = "https://dev/ABC/v1/XYZ?itemnumber%255Bin%255D=%255B3001%252C3005%252C202%255D&limit=2&apikey=4zVYEk2Xg8zvwYxNnW&offset=2";

String decodedURL = URLDecoder.decode(url1, "UTF-8");

System.out.println(decodedURL);

Expected output:

https://dev/ABC/v1/XYZ?itemnumber[in]=[3001,3005,20]&limit=2&offset=1&apikey=4zVYEk2Xg8zvwYxNnW

Error output:

https://dev/ABC/v1/XYZ?itemnumber%5Bin%5D=%5B3001%2C3005%2C202%5D&limit=2&apikey=4zVYEk2Xg8zvwYxNnW&offset=1

Why would you expect `offset=1` when your input ends with `offset=2`? — Andy Turner, Sep 12 '22 at 10:23
it still says `offset=2` in the code snippet. Also, the API key differs. — Andy Turner, Sep 12 '22 at 10:37

score 2 · Answer 1 · answered Sep 12 '22 at 10:26

Your string is double-URL encoded, see https://ideone.com/CQQbPz:

String url1 = "https://dev/ABC/v1/XYZ?itemnumber%255Bin%255D=%255B3001%252C3005%252C202%255D&limit=2&apikey=4zVYEk2Xg8zvwYxNnW&offset=2";

System.out.println(URLDecoder.decode(url1, "UTF-8"));
System.out.println(URLDecoder.decode(URLDecoder.decode(url1, "UTF-8"), "UTF-8"));

Output:

https://dev/ABC/v1/XYZ?itemnumber%5Bin%5D=%5B3001%2C3005%2C202%5D&limit=2&apikey=4zVYEk2Xg8zvwYxNnW&offset=2
https://dev/ABC/v1/XYZ?itemnumber[in]=[3001,3005,202]&limit=2&apikey=4zVYEk2Xg8zvwYxNnW&offset=2

score -4 · Answer 2 · answered Sep 12 '22 at 10:28

-4

Browsers and many other http programs convert illegitimate url request symbols to URL encoding scheme that place a % percent sign in front of two numerals. Before use, use

String decoded = java.net.URLDecoder.decode(request);

answered Sep 12 '22 at 10:28

Samuel Marchant

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The question shows that URLDecoder.decode is already being used. – VGR Sep 12 '22 at 12:18

How to avoid special character from URL using java

2 Answers2