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Insert text in middle of String (link)

I am getting a URL from a message that is in the form https://example.com/eUjKSv, however I need to insert a "tag" /raw/ in between .com/ and eUjKSv.
I was wondering what would be the easiest way to do it, currently I have a very "hacky" way to achieve it, new URL("https://example.com/raw" + new URL(link).getPath()), I know it's pretty awful and only works if I know exactly the URL. Any suggestions on how to make this better? I thought about regex but couldn't think of a good one to capture it.

You can use either the URL class or the URI class. They both work for this.
URL baseUrl = new URL("https://example.com/eUjKSv");
URL rawUrl = new URL(baseUrl, "/raw" + baseUrl.getPath());
System.out.println("baseUrl = " + baseUrl);
System.out.println("rawUrl = " + rawUrl);
URI baseUri = new URI("https://example.com/eUjKSv");
URI rawUri = baseUri.resolve("/raw" + baseUri.getPath());
System.out.println("baseUri = " + baseUri);
System.out.println("rawUri = " + rawUri);
Output
baseUrl = https://example.com/eUjKSv
rawUrl = https://example.com/raw/eUjKSv
baseUri = https://example.com/eUjKSv
rawUri = https://example.com/raw/eUjKSv

Generating an SAS Token in Java to download a file in an Azure Data Storage container

Trying to generate an SAS Token to access certain files in a Storage Account. I'm using the methods listed here:
https://learn.microsoft.com/en-us/rest/api/eventhub/generate-sas-token
Now, the problem I have is I cannot, for the life of me, make the sasToken string work. If I generate the token via the Portal (Shared Access Signature in the Storage Account), I can access those files via a URL with the provided Token.
However I have yet to be able to generate an SAS token programmatically via Java using the methods I linked above. I think my problem is the StringToSign that is being encrypted. I've been following this example when constructing the string to encrypt:
https://learn.microsoft.com/en-us/rest/api/storageservices/constructing-an-account-sas
All my efforts have resulted in either:
<AuthenticationErrorDetail>Signature fields not well formed.</AuthenticationErrorDetail>
or
<AuthenticationErrorDetail>Signature did not match. String to sign used was <insert string details here>
Looking at the Portal generated sasToken that works for me:
?sv=2017-11-09&ss=f&srt=o&sp=r&se=2018-12-06T22:15:20Z&st=2018-12-06T14:15:20Z&spr=https&sig=%2Bi1TWv5D80U%2BoaIeoBh1wjaO1p4xVFx4nRZt%2FzwiszY%3D
It seems I need a String like so:
String stringToSign = accountName + "\n" +
"r\n" +
"f\n" +
"o\n" +
URLEncoder.encode(start, "UTF-8") + "\n" +
URLEncoder.encode(expiry, "UTF-8") + "\n" +
"\n" +
"https\n" +
azureApiVersion;
Where accountName is the storage account name from Azure, and start/expiry are the start and expiry strings (ie- 2018-12-06T22:15:20Z) and azureApiVersion is "2017-11-09".
I then try to return the token after constructing the string like so:
String signature = getHMAC256(key, stringToSign);
sasToken = "sv=" + azureApiVersion +
"&ss=f" +
"&srt=o" +
"&sp=r" +
"&se=" +URLEncoder.encode(expiry, "UTF-8") +
"&st=" + URLEncoder.encode(start, "UTF-8") +
"&spr=https" +
"&sig=" + URLEncoder.encode(signature, "UTF-8");
I've tried URL encoding and not URL encoding the the start/expiry dates as well, just in case that was messing things up. What am I missing?

Three points to fix
getHMAC256 method problem as mentioned by #Gaurav
Don't encode expiry and start in stringToSign or the signature won't match. Because the encoded part in url will be decoded by Azure Storage Service to calculate the expected signature.
In stringToSign, miss one \n after azureApiVersion.
Here's the complete sample.
public static void GetFileSAS(){
String accountName = "accountName";
String key = "accountKey";
String resourceUrl = "https://"+accountName+".file.core.windows.net/fileShare/fileName";
String start = "startTime";
String expiry = "expiry";
String azureApiVersion = "2017-11-09";
String stringToSign = accountName + "\n" +
"r\n" +
"f\n" +
"o\n" +
start + "\n" +
expiry + "\n" +
"\n" +
"https\n" +
azureApiVersion+"\n";
String signature = getHMAC256(key, stringToSign);
try{
String sasToken = "sv=" + azureApiVersion +
"&ss=f" +
"&srt=o" +
"&sp=r" +
"&se=" +URLEncoder.encode(expiry, "UTF-8") +
"&st=" + URLEncoder.encode(start, "UTF-8") +
"&spr=https" +
"&sig=" + URLEncoder.encode(signature, "UTF-8");
System.out.println(resourceUrl+"?"+sasToken);
} catch (UnsupportedEncodingException e) {
e.printStackTrace();
}
}
private static String getHMAC256(String accountKey, String signStr) {
String signature = null;
try {
SecretKeySpec secretKey = new SecretKeySpec(Base64.getDecoder().decode(accountKey), "HmacSHA256");
Mac sha256HMAC = Mac.getInstance("HmacSHA256");
sha256HMAC.init(secretKey);
signature = Base64.getEncoder().encodeToString(sha256HMAC.doFinal(signStr.getBytes("UTF-8")));
} catch (Exception e) {
e.printStackTrace();
}
return signature;
}

I got a simpler method
SharedAccessAccountPolicy sharedAccessAccountPolicy = new SharedAccessAccountPolicy();
sharedAccessAccountPolicy.setPermissionsFromString("racwdlup");
long date = new Date().getTime();
long expiryDate = new Date(date + 8640000).getTime();
sharedAccessAccountPolicy.setSharedAccessStartTime(new Date(date));
sharedAccessAccountPolicy.setSharedAccessExpiryTime(new Date(expiryDate));
sharedAccessAccountPolicy.setResourceTypeFromString("sco");
sharedAccessAccountPolicy.setServiceFromString("bfqt");
String sasToken = "?" + storageAccount.generateSharedAccessSignature(sharedAccessAccountPolicy);
You can get the storage account like this:
private String storageConnectionString = "DefaultEndpointsProtocol=https;AccountName=<storage name>;AccountKey=<your key>;EndpointSuffix=core.windows.net";
storageAccount = CloudStorageAccount.parse(storageConnectionString);

How to send plus operator in url in java

I am fetching data from server in my project. In some condition there is a need to send + operator in url with parameter. How can i send "+" in url with parameter.
here is my url
http://www.needsthesupermarket.com/webservice/dp/addCart.php?cart_id=43530&cust_id=13936&pid=11303&qty=1&combination=2 ltr + 1 kg&guest_id=2509245
In blank space i replace with %20. but problem with + sign. How can i send it in url?

%26 -> &
%2B -> +
You can decode/encode here

You should encode your GET parameters:
Uri.encode(someParam)
For example if you have some Map paramsGet with GET parameters:
final StringBuilder url = new StringBuilder("http://example.com");
String delim = "?";
for (final Map.Entry<String, String> entry : paramsGet.entrySet()) {
url.append(delim).append(entry.getKey()).append("=").append(Uri.encode(entry.getValue()));
delim = "&";
}

To Encode use
String encodedInput = java.net.URLEncoder.encode(inputText, "UTF-8");
To Decode use
String decodedInput = java.net.URLDecoder.decode(encodedInput, "UTF-8");

POST data to other URI with URL change in REST (POST and Redirect)

I need to POST data and at the same time redirect to that URL in REST environment. I can do this for normal strings, but the requirement is to POST specific Object.
The way I do it for normal string is -
public Response homePage(#FormParam("username") String username,
#FormParam("passwordhash") String password) {
return Response.ok(PreparePOSTForm(username)).build();
}
private static String PreparePOSTForm(String username)
{
//Set a name for the form
String formID = "PostForm";
String url = "home";
//Build the form using the specified data to be posted.
StringBuilder strForm = new StringBuilder();
strForm.append("<form id=\"" + formID + "\" name=\"" +
formID + "\" action=\"" + url +
"\" method=\"POST\">");
strForm.append("<input type=\"hidden\" name=\"" + "username" +
"\" value=\"" + username + "\">");
strForm.append("</form>");
//Build the JavaScript which will do the Posting operation.
StringBuilder strScript = new StringBuilder();
strScript.append("<script language=\"javascript\">");
strScript.append("var v" + formID + " = document." +
formID + ";");
strScript.append("v" + formID + ".submit();");
strScript.append("</script>");
//Return the form and the script concatenated.
//(The order is important, Form then JavaScript)
return strForm.toString() + strScript.toString();
}
But this method is not sending Objects. I need a work around to send complex Objects. Please help me with this issue.
Thanks in advance.

URL in JSON object as POST request Android

Please help me to send a JSON object in POST HTTP request through HttpClient, in Android.
The problem I am facing is that the JSON object having the URL is replaced by forward slash ,i.e
originally it should have the following value in JSON object
{"product":
{"featured_src":"https:\/\/example.com\/wp-content\/uploads\/2015\/06\/sidney-compressed.jpg,
"short_description":"this is a test","title":"Raiders from the North"}
}
i tried many options to keep it in the above format. But it always comes as {"featured_src":

We assume this is your input
private final static String JSON_DATA = "{"
+ " \"product\": ["
+ " {"
+ " \"featured_src\": \"https:\\/\\/example.com\\/wp-content"
+ "\\/uploads\\/2015\\/06\\/sidney-compressed.jpg\","
+ " \"short_description\": \"this is a test\","
+ " \"title\" : \"Raiders from the North\""
+ " }"
+ " ]"
+ "}";
You could use replace to do the trick.
YOUR_STRING.replace("\\", "");
Finally your method would look like this, by passing your string as parameter
private static String jsonUrlCorrector(String json_data) {
json_data = json_data.replace("\\", "");
return json_data;
}
Here is the input:
{"product":[{"featured_src":"https:\/\/example.com\/wp-content\/uploads\/2015\/06\/sidney-compressed.jpg","short_description": "this is a test","title":"Raiders from the North"}]}
Here is the output
{"product":[{"featured_src":"https://example.com/wp-content/uploads/2015/06/sidney-compressed.jpg","short_description":"this is a test","title":"Raiders from the North"}]}