url and name spaces java convertion - java

I need to be able to convert:
(url) http://www.joe90.com/showroom
to
(namespace) com.joe90.showroom
I can do this using tokens etc, and a enforced rule set.
However, is there a way (a java package) that will do this for me?
or do i need to write one myself?
Thanks

java.net.URL url = new java.net.URL("http://www.joe90.com/showroom");
String tokens[] = url.getHostname().split(".");
StringBuilder sb = new StringBuilder();
for (int i=0; i<tokens.length; i++) {
if (i > 1) {
sb.append('.');
}
sb.append(tokens[i]);
}
String namespace = sb.toString();
Alternatively you can parse the hostname out.
Pattern p = Pattern.compile("^(\\w+://)?(.*?)/");
Matcher m = p.matcher(url); // string
if (m.matches()) {
String tokens[] = m.group(2).split(".");
// etc
}
Of course that regex doesn't match all URLs, for example:
http://username#hostname.com/...
That's why I suggested using java.net.URL: it does all the URL validation and parsing for you.

Your best bet would be to split the string based on the . and / characters (e.g. using Sting.split(), and then concatenate the pieces in reverse order, skipping over any you don't want to include (e.g. www)

Related

java regex to extract the password from url path between the last 2 slashes

how can i extract the password form the following links using java code:
it's one link and comes each time with different structure.
the password is always between the last 2 slashes.
http://example.com:8080/files/user1/password123/12351.png
http://example.com:8080/user1/password123/956253.png
http://example.com:8080/user1/password123/3652
i need to get the password: password123
currently i use:
String url = "http://example.com:8080/files/user1/password123/12351.png";
String[] split = url .split("/");
//i reverse the array
String[] temp = new String[split.length];
for(int i = split.length - 1; i > -1; i --){
temp[split.length - i -1] = split[i];
}
split = temp;
String password = split[1];
but this depends on the index of array.
is there a regex code to do so?
regards
If the structure of your data is always like that and password is always the between the last 2 slashes you could just use split and use the length of the array minus 2.
Apart from verifying that the index exists etc, you might use:
String url = "http://example.com:8080/files/user1/password123/12351.png";
String[] split = url.split("/");
System.out.println(split[split.length - 2]);
Demo
I'd recommend don't go with split, try a regex.
String url = "http://example.com:8080/files/user1/password123/12351.png";
String pattern = ".*\\/([^\\/]+)\\/[\\w\\.]+";
Pattern r = Pattern.compile(pattern);
String pwd = "";
Matcher m = r.matcher(line);
if (m.find()) {
pwd = m.group(1);
}
else {
System.out.println("NO MATCH");
}
Regular expressions are a heavyweight solution, so I prefer to avoid using them unless they are needed.
Instead, you can just look for the last / character, then look for the / character before that one:
int lastSlash = url.lastIndexOf('/');
int secondToLastSlash = url.lastIndexOf('/', lastSlash - 1);
String password = url.substring(secondToLastSlash + 1, lastSlash);
password = URLDecoder.decode(password, "UTF-8");
The last line is needed because the password might contain characters which cannot be directly present in a URL. For instance, the password sword{fish} would occur in a URL as sword%7bfish%7d.

N-th indexOf in String?

I need to extract a sub-string of a URL.
URLs
/service1/api/v1.0/foo -> foo
/service1/api/v1.0/foo/{fooId} -> foo/{fooId}
/service1/api/v1.0/foo/{fooId}/boo -> foo/{fooId}/boo
And some of those URLs may have request parameters.
Code
String str = request.getRequestURI();
str = str.substring(str.indexOf("/") + 1);
str = str.substring(str.indexOf("/") + 1);
str = str.substring(str.indexOf("/") + 1);
str = str.substring(str.indexOf("/") + 1, str.indexOf("?"));
Is there a better way to extract the sub-string instead of recurrent usage of indexOf method?
There are many alternative ways:
Use Java-Stream API on splitted String with \ delimiter:
String str = "/service1/api/v1.0/foo/{fooId}/boo";
String[] split = str.split("\\/");
String url = Arrays.stream(split).skip(4).collect(Collectors.joining("/"));
System.out.println(url);
With the elimination of the parameter, the Stream would be like:
String url = Arrays.stream(split)
.skip(4)
.map(i -> i.replaceAll("\\?.+", ""))
.collect(Collectors.joining("/"));
This is also where Regex takes its place! Use the classes Pattern and Matcher.
String str = "/service1/api/v1.0/foo/{fooId}/boo";
Pattern pattern = Pattern.compile("\\/.*?\\/api\\/v\\d+\\.\\d+\\/(.+)");
Matcher matcher = pattern.matcher(str);
while (matcher.find()) {
System.out.println(matcher.group(1));
}
If you rely on the indexOf(..) usage, you might want to use the while-loop.
String str = "/service1/api/v1.0/foo/{fooId}/boo?parameter=value";
String string = str;
while(!string.startsWith("v1.0")) {
string = string.substring(string.indexOf("/") + 1);
}
System.out.println(string.substring(string.indexOf("/") + 1, string.indexOf("?")));
Other answers include a way that if the prefix is not mutable, you might want to use only one call of idndexOf(..) method (#JB Nizet):
string.substring("/service1/api/v1.0/".length(), string.indexOf("?"));
All these solutions are based on your input and fact, the pattern is known, or at least the number of the previous section delimited with \ or the version v1.0 as a checkpoint - the best solution might not appear here since there are unlimited combinations of the URL. You have to know all the possible combinations of input URL to find the best way to handle it.
Path is quite useful for that :
public static void main(String[] args) {
Path root = Paths.get("/service1/api/v1.0/foo");
Path relativize = root.relativize(Paths.get("/service1/api/v1.0/foo/{fooId}/boo"));
System.out.println(relativize);
}
Output :
{fooId}/boo
How about this:
String s = "/service1/api/v1.0/foo/{fooId}/boo";
String[] sArray = s.split("/");
StringBuilder sb = new StringBuilder();
for (int i = 4; i < sArray.length; i++) {
sb.append(sArray[i]).append("/");
}
sb.deleteCharAt(sb.length() - 1);
System.out.println(sb.toString());
Output:
foo/{fooId}/boo
If the url prefix is always /service1/api/v1.0/, you just need to do s.substring("/service1/api/v1.0/".length()).
There are a few good options here.
1) If you know "foo" will always be the 4th token, then you have the right idea already. The only issue with your way is that you have the information you need to be efficient, but you aren't using it. Instead of copying the String multiple times and looping anew from the beginning of the new String, you could just continue from where you left off, 4 times, to find the starting point of what you want.
String str = "/service1/api/v1.0/foo/{fooId}/boo";
// start at the beginning
int start = 0;
// get the 4th index of '/' in the string
for (int i = 0; i != 4; i++) {
// get the next index of '/' after the index 'start'
start = str.indexOf('/',start);
// increase the pointer to the next character after this slash
start++;
}
// get the substring
str = str.substring(start);
This will be far, far more efficient than any regex pattern.
2) Regex: (java.util.regex.*). This will work if you what you want is always preceded by "service1/api/v1.0/". There may be other directories before it, e.g. "one/two/three/service1/api/v1.0/".
// \Q \E will automatically escape any special chars in the path
// (.+) will capture the matched text at that position
// $ marks the end of the string (technically it matches just before '\n')
Pattern pattern = Pattern.compile("/service1/api/v1\\.0/(.+)$");
// get a matcher for it
Matcher matcher = pattern.matcher(str);
// if there is a match
if (matcher.find()) {
// get the captured text
str = matcher.group(1);
}
If your path can vary some, you can use regex to account for it. e.g.: service/api/v3/foo/{bar}/baz/" (note varying number formats and trailing '/') could be matched as well by changing the regex to "/service\\d*/api/v\\d+(?:\\.\\d+)?/(.+)(?:/|$)"

Regex Redirect URL excludes token

I'm trying to create a redirect URL for my client. We have a service that you specify "fromUrl" -> "toUrl" that is using a java regex Matcher. But I can't get it work to include the token in when it converts it. For example:
/fromurl/login?token=7c8Q8grW5f2Kz7RP1%2FWsqpVB%2FEluVOGfXQdW4I0v82siR2Ism1D8VCvEmKJr%2BKhHhicwPey0uIiTxN049Be8TNsypf
Should be:
/tourl/login?token=7c8Q8grW5f2Kz7RP1%2FWsqpVB%2FEluVOGfXQdW4I0v82siR2Ism1D8VCvEmKJr%2BKhHhicwPey0uIiTxN049Be8TNsypf
but it excludes the token so the result I get is:
/fromurl/login/
/tourl/login/
I tried various regex patterns like: " ?.* and [%5E//?]+)/([^/?]+)/(?.*)?$ and (/*) etc" but no one seems to work.
I'm not that familiar with regex. How can I solve this?
This can be easily done using simple string replace but if you insist on using regular expressions:
Pattern p = Pattern.compile("fromurl");
String originalUrlAsString = "/fromurl/login?token=7c8Q8grW5f2Kz7RP1%2FWsqpVB%2FEluVOGfXQdW4I0v82siR2Ism1D8VCvEmKJr%2BKhHhicwPey0uIiTxN049Be8TNsypf ";
String newRedirectedUrlAsString = p.matcher(originalUrlAsString).replaceAll("tourl");
System.out.println(newRedirectedUrlAsString);
If I understand you correctly you need something like this?
String from = "/my/old/url/login?token=7c8Q8grW5f2Kz7RP1%2FWsqpVB%2FEluVOGfXQdW4I0v82siR2Ism1D8VCvEmKJr%2BKhHhicwPey0uIiTxN049Be8TNsypf";
String to = from.replaceAll("\\/(.*)\\/", "/my/new/url/");
System.out.println(to); // /my/new/url/login?token=7c8Q8grW5f2Kz7RP1%2FWsqpVB%2FEluVOGfXQdW4I0v82siR2Ism1D8VCvEmKJr%2BKhHhicwPey0uIiTxN049Be8TNsypf";
This will replace everything between the first and the last forward slash.
Can you detail more exactly what the original expression is like? This is necessary because the regular expression is based on it.
Assuming that the first occurrence of fromurl should simply be replaced with the following code:
String from = "/fromurl/login?token=7c8Q8grW5f2Kz7RP1%2FWsqpVB%2FEluVOGfXQdW4I0v82siR2Ism1D8VCvEmKJr%2BKhHhicwPey0uIiTxN049Be8TNsypf";
String to = from.replaceFirst("fromurl", "tourl");
But if it is necessary to use more complex rules to determine the substring to replace, you can use:
String from = "/fromurl/login?token=7c8Q8grW5f2Kz7RP1%2FWsqpVB%2FEluVOGfXQdW4I0v82siR2Ism1D8VCvEmKJr%2BKhHhicwPey0uIiTxN049Be8TNsypf";
String to = "";
String regularExpresion = "(<<pre>>)(fromurl)(<<pos>>)";
Pattern pattern = Pattern.compile(regularExpresion);
Matcher matcher = pattern.matcher(from);
if (matcher.matches()) {
to = from.replaceAll(regularExpresion, "$1tourl$3");
}
NOTE: pre and pos targets are referencial because I don't know the real expresion of the url
NOTE 2: $1 and $3 refer to the first and the third group
Although existing answers should solve the issue and some are similar, maybe below solution would be of help, with quite an easy regex being used (assuming you get input of same format as your example):
private static String replaceUrl(String inputUrl){
String regex = "/.*(/login\\?token=.*)";
String toUrl = "/tourl";
Pattern p = Pattern.compile(regex);
Matcher matcher = p.matcher(inputUrl);
if (matcher.find()) {
return toUrl + matcher.group(1);
} else
return null;
}
You can write a test if it works for other expected inputs/outputs if you want to change format and adjust regex:
String inputUrl = "/fromurl/login?token=7c8Q8grW5f2Kz7RP1%2FWsqpVB%2FEluVOGfXQdW4I0v82siR2Ism1D8VCvEmKJr%2BKhHhicwPey0uIiTxN049Be8TNsypf";
String expectedUrl = "/tourl/login?token=7c8Q8grW5f2Kz7RP1%2FWsqpVB%2FEluVOGfXQdW4I0v82siR2Ism1D8VCvEmKJr%2BKhHhicwPey0uIiTxN049Be8TNsypf";
if (expectedUrl.equals(replaceUrl(inputUrl))){
System.out.println("Success");
}

Parse string value from URL

I have a string (which is an URL) in this pattern https://xxx.kflslfsk.com/kjjfkskfjksf/v1/files/media/93939393hhs8.jpeg
now I want to clip it to this
media/93939393hhs8.jpeg
I want to remove all the characters before the second last slash /.
i'm a newbie in java but in swift (iOS) this is how we do this:
if let url = NSURL(string:"https://xxx.kflslfsk.com/kjjfkskfjksf/v1/files/media/93939393hhs8.jpeg"), pathComponents = url.pathComponents {
let trimmedString = pathComponents.suffix(2).joinWithSeparator("/")
print(trimmedString) // "output = media/93939393hhs8.jpeg"
}
Basically, I'm removing everything from this Url expect of last 2 item and then.
I'm joining those 2 items using /.
String ret = url.substring(url.indexof("media"),url.indexof("jpg"))
Are you familiar with Regex? Try to use this Regex (explained in the link) that captures the last 2 items separated with /:
.*?\/([^\/]+?\/[^\/]+?$)
Here is the example in Java (don't forget the escaping with \\:
Pattern p = Pattern.compile("^.*?\\/([^\\/]+?\\/[^\\/]+?$)");
Matcher m = p.matcher(string);
if (m.find()) {
System.out.println(m.group(1));
}
Alternatively there is the split(..) function, however I recommend you the way above. (Finally concatenate separated strings correctly with StringBuilder).
String part[] = string.split("/");
int l = part.length;
StringBuilder sb = new StringBuilder();
String result = sb.append(part[l-2]).append("/").append(part[l-1]).toString();
Both giving the same result: media/93939393hhs8.jpeg
string result=url.substring(url.substring(0,url.lastIndexOf('/')).lastIndexOf('/'));
or
Use Split and add last 2 items
string[] arr=url.split("/");
string result= arr[arr.length-2]+"/"+arr[arr.length-1]
public static String parseUrl(String str) {
return (str.lastIndexOf("/") > 0) ? str.substring(1+(str.substring(0,str.lastIndexOf("/")).lastIndexOf("/"))) : str;
}

Java regex expression to sanitize an uploaded file name

I'm trying to sanitize a String that contains an uploaded file's name. I'm doing this because the files will be downloaded from the web and, plus, I want to normalize the names. This is what I have so far:
private String pattern = "[^0-9_a-zA-Z\\(\\)\\%\\-\\.]";
//Class methods & stuff
private String sanitizeFileName(String badFileName) {
StringBuffer cleanFileName = new StringBuffer();
Pattern filePattern = Pattern.compile(pattern);
Matcher fileMatcher = filePattern.matcher(badFileName);
boolean match = fileMatcher.find();
while(match) {
fileMatcher.appendReplacement(cleanFileName, "");
match = fileMatcher.find();
}
return cleanFileName.substring(0, cleanFileName.length() > 250 ? 250 : cleanFileName.length());
}
This works ok, but for a strange reason the extension of the file is erased. i.e. "p%Z_-...#!$()=¡¿&+.jpg" ends up being "p%Z_-...()".
Any Idea as to how should I tune up my regex?
You need a Matcher#appendTail at the end of your loop.
One line solution:
return badFileName.replaceAll("[^0-9_a-zA-Z\\(\\)\\%\\-\\.]", "");
If you want to restrict it to just alphanumeric and space:
return badFileName.replaceAll("[^a-zA-Z0-9 ]", "");
Cheers :)

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