Develop Reference

Removing some patterns before a particular string using Java

I want to remove some patterns between two "/" from the string, for example:
Input
/DT_Gateway/gateway/ACC/input/..
Output
/DT_Gateway/gateway/ACC
I have tried writing this code, but getting an error. I am new to Java, please help.
public class cut {
public static void main(String[] args) {
String myString = "/DT_Gateway/gateway/ACC/input/..";
String newString = myString.substring(myString.lastIndexOf("/")+1, myString.indexOf("/.."));
System.out.println(newString);
}
}

Note : this is a very custom solution to your problem, not a general way to do it .
String myString = "/DT_Gateway/gateway/ACC/input/..";
String newString = myString.substring(0, myString.indexOf("/i"));
System.out.println(newString);

Try this solution with regex:
"/DT_Gateway/gateway/ACC/input/..".replaceAll("(/[^/]+){2}$", "")
The regex is basically find two of the following pattern at the end of the string
/[^/]+
This means a forward slash followed by an unlimited number of non-forward-slashes.

It seems that relative paths should be normalized, XXX/.. removed.
That would go as follows
String myString = "/DT_Gateway/gateway/ACC/input/..";
System.out.println(myString.replaceAll("/[^/]+/\\.\\.(/|$)", "$1"));
String myString2 = "/DT_Gateway/gateway/ACC/input/../x.txt";
System.out.println(myString2.replaceAll("/[^/]+/\\.\\.(/|$)", "$1"));
Path path = Paths.get(myString);
System.out.println(path.normalize().toString());
Path path2 = Paths.get(myString2);
System.out.println(path2.normalize().toString());
/DT_Gateway/gateway/ACC
/DT_Gateway/gateway/ACC/x.txt
/DT_Gateway/gateway/ACC
/DT_Gateway/gateway/ACC/x.txt
Java Path is - for (all kinds of) file systems - quite the tool.
Especially as there is XXX/../..

Using regular expressions to rename a string

In java, I want to rename a String so it always ends with ".mp4"
Suppose we have an encoded link, looking as follows:
String link = www.somehost.com/linkthatIneed.mp4?e=13974etc...
So, how do I rename the link String so it always ends with ".mp4"?
link = www.somehost.com/linkthatIneed.mp4 <--- that's what I need the final String to be.

Just get the string until the .mp4 part using the following regex:
^(.*\.mp4)
and the first captured group is what you want.
Demo: http://regex101.com/r/zQ6tO5

Another way to do this would be to split the string with ".mp4" as a split char and then add it again :)
Something like :
String splitChar = ".mp4";
String link = "www.somehost.com/linkthatIneed.mp4?e=13974etcrezkhjk"
String finalStr = link.split(splitChar)[0] + splitChar;
easy to do ^^
PS: I prefer to pass by regex but it ask for more knowledge about regex ^^

Well you can also do this:
Match the string with the below regex
\?.*
and replace it with empty string.
Demo: http://regex101.com/r/iV1cZ8

Try below code,
private String trimStringAfterOccurance(String link, String occuranceString) {
Integer occuranceIndex = link.indexOf(occuranceString);
String trimmedString = (String) link.subSequence(0, occuranceIndex + occuranceString.length() );
System.out.println(trimmedString);
return trimmedString;
}

How to Check filename

I have a method that reads filename for a file from a certain source. My method should handle two types of files. My next method depends on the name of the file.
_InPayed.txt" "_OutPayed.txt
My problem is how to check if the filename is ..._inpayed Or ..._OutPayed
How to check the string after the strick " _"
Code:
public class FilenameDemo {
public static void main(String[] args) {
final String FPATH = "/home/mem/"filename.txt";
System.out.println("Extension = " + myHomePage.extension());
System.out.println("Filename = " + myHomePage.filename());
}
}

No need for subString. A simple call to contains(...) is all you need. More importantly, learn to use the API.
if (myString.toLowerCase().contains("inpayed")) {
// do something
}
String API

If you want to check the certain string in the file name then use contains method.
&
You can get the file name after _ using below expression
System.out.println("Filename = "+FPATH.substring(FPATH.lastIndexOf("_")+1,FPATH.lastIndexOf(".")));

The string must contain one and only one _ for this to work.
String fullFile="whatever_InOutPayed.txt"
String[] split = file.split("_");
// split[0] = "whatever"
// split[1] = "InOutPayed.txt"
String file = split[1];
If it contains more than one then take the last element of the array
String file = split[split.length - 1];
or you can easily use String.contains().

You can use substring() method to extract a desired part of a file name stored as String. Or if the part you are checking will always be at the end of the String a simpler option is to use endsWith(). Check the documentation for details about the method usage.

Query regarding regular expression

hi I have a string like this:
String s = "#Path(\"/BankDBRestService/customerExist(String")\";
I want to make that string as
#Path("/BankDBRestService/customerExist")
I tried this:
String foo = s.replaceAll("[(](.*)", "");
i am getting output as
#Path
can anyone please provide me the reqular expression to make this work

Try this one :
String s = "#Path(\"/BankDBRestService/customerExist(String\")";
String res = s.replaceAll("[(]([a-zA-Z_])+", "");
System.out.println(res);
Output : #Path("/BankDBRestService/customerExist")
If your string is "#Path(\"/BankDBRestService/customerExist(String)\")" i.e. with closed parenthesis then use regex [(]([a-zA-Z_])+[)]

try this
String foo = s.replaceAll("(.*)\\(.*\\)", "$1");

Problem in replacing special characters in a String in java

I got a String as response from server which is like the below:
hsb:\\\10.217.111.33\javap\Coventry\
Now I want to parse this string in such a way that I need to replace all \ with /.
Also I need to remove the first part of the String which is hsb:\\\
So, my resultant string should be of like this :
10.217.111.33/javap/coventry/
Can anyone help me by providing sample java code for this problem.

Here you have a "dirty" startup "solution":
String s = "hsb:\\\\\\10.217.111.33\\javap\\Coventry\\";
String w = s.replace('\\', '/');
String x = w.replace("hsb:///", "");

String result = yourString.substring(7);
result = result.replaceAll("\\\\", "/");