Extract last number after decimal - java

I am getting a piece of JSON text from a url connection and saving it to a string currently as such:
...//setting up url and connection
BufferedReader in = new BufferedReader(new InputStreamReader(connection.getInputStream()));
String str = in.readLine();
When I print str, I correctly find the data {"build":{"version_component":"1.0.111"}}
Now I want to extract the 111 from str, but I am having some trouble.
I tried
String afterLastDot = inputLine.substring(inputLine.lastIndexOf(".") + 1);
but I end up with 111"}}
I need a solution that is generic so that if I have String str = {"build":{"version_component":"1.0.111111111"}}; the solution still works and extracts 111111111 (ie, I don't want to hard code extract the last three digits after the decimal point)

If you cannot use a JSON parser then you can this regex based extraction:
String lastNum = str.replaceAll("^.*\\.(\\d+).*", "$1");
RegEx Demo
^.* is greedy match that matches everything until last DOT and 1 or more digits that we put in group #1 to be used in replacement.

Find the start and the end indexes of the String you need and substring(start, end) :
// String str = "{"build":{"version_component":"1.0.111"}};" cannot compile without escaping
String str = "{\"build\":{\"version_component\":\"1.0.111\"}}";
int start = str.lastIndexOf(".")+1;
int end = str.lastIndexOf("\"");
String substring = str.substring(start,end);

just use JSON api
JSONObject obj = new JSONObject(str);
String versionComponent= obj.getJSONObject("build").getString("version_component");
Then just split and take the last element
versionComponent.split("\\.")[2];

Please, your can try the following code :
...
int index = inputLine.lastIndexOf(".")+1 ;
String afterLastDot = inputLine.substring(index, index+3);

With Regular Expressions (Rexp),
You can solve your problem like this ;
Pattern pattern = Pattern.compile("111") ;
Matcher matcher = pattern.matcher(str) ;
while(matcher.find()){
System.out.println(matcher.start()+" "+matcher.end());
System.out.println(str.substring(matcher.start(), matcher.end()));
}

Related

How to split a string having [] as delimiters in java

I want to remove [ ] braces from the below string-
"[maths=100, english=20]"
I have tried doing it in following ways but in both the trials it is not removing the end ] brace.
Approach 1:
String[] metrics= "[maths=100, english=20]";
String[] value = metrics[1].split("\\[");
String[] finalValue = value[1].split("\\]");
System.out.println(finalValue[0]); // this should give string as maths=100, english=20
Approach 2:
String[] metrics= "[maths=100, english=20]";
String[] value = metrics[1].split("\\[\\]");
System.out.println(finalValue[1]); // this should give string as maths=100, english=20
Can anyone guide me where i am doing it wrong?
Try this code
String metrics= "[maths=100, english=20]";
String[] split = metrics.split("\\[|]");
System.out.println(split[1]);
it prints
"maths=100, english=20"
Or you can simply replace all [ and ] character
String metrics = "[maths=100, english=20]";
metrics = metrics.replace("[", "").replace("]", "");
System.out.println(metrics);
If you simply want to trim and clean your data then you can do a simple check and substring.
String input = ...;
String cleanedInput = input.trim();
if (cleanedInput.startsWith("[") && cleanedInput.endsWith("]")) {
cleanedInput = cleanedInput.substring(1, cleanedInput.length() - 1);
System.out.println(cleanedInput);
}
If you're wanting to match and capture from a larger set of data then you can use RegEx patterns with capture groups to match and capture the data you want.
For parsing a proper document structure though you should try to use a real parser but if you truly are just trying to match and capture some simple data then RegEx will often be ok.
String input = ...;
// RegEx pattern "\[([^\[\]]*)\]" anything inside braces except other braces
Pattern pattern = Pattern.compile("\\[([^\\[\\]]*)\\]");
Matcher matcher = pattern .matcher(input);
while (matcher.find()) {
String data = matcher.group(1);
System.out.println(data);
}
You can simply replace the braces like this:
String s = "[maths=100, english=20]";
s = s.replace("[", "").replace("]", "");
System.out.println(s);

Regex to find text between string pattren

String: [img border=0]/scm/images/bbcode/sets/misc/bullet_go.png[/img]
Result I Want: [img border=0]images/bbcode/sets/misc/bullet_go.png[/img] without /scm/ text.
Issue: Text scm is not static, could be any other text in data.
What I want: Have a look to this string
[img border=0]/scm/images/bbcode/sets/misc/bullet_go.png[/img]
Regex which can fetch a text between ] and images/bbcode/ so the regex will detect the \scm\ text and then can remove this \scm\ from String data and end result will look like
[img border=0]images/bbcode/sets/misc/bullet_go.png[/img]
PS: I am implementing this logic in Java.
you can reach the goal without using regex, too.
since you said that the other parts are static, try this:
String myStr = "[img border=0]/scm/images/bbcode/sets/misc/bullet_go.png[/img]";
myStr = "[img border=0]" + myStr.substring(myStr.indexOf("images"));
System.out.println(myStr);
and the output will be:
[img border=0]images/bbcode/sets/misc/bullet_go.png[/img]
I have captured text between '] and /images..' and replace this text with "". Check the following demo:
String s = "[img border=0]/scm/images/bbcode/sets/misc/bullet_go.png[/img]";
s = s.replaceAll("(?<=])/[^/]+/","");
System.out.println(s);
if [img border=0] dynamic, you can take all except /scm/
some demo
String input = "[img border=0]/scm/images/bbcode/sets/misc/bullet_go.png[/img]";
Pattern p = Pattern.compile("(^.*\\])\\/.*?\\/(.*$)");
Matcher m = p.matcher(input);
if (m.find()) {
String output = m.replaceFirst("$1$2");
System.out.println(output);
}
// -> [img border=0]images/bbcode/sets/misc/bullet_go.png[/img]
I found one more way to solve this same problem
String pattereString = "].*/images";
String maineString = "[img border=0]/scm/images/bbcode/sets/misc/bullet_go.png[/img]";
maineString = maineString.replaceAll(pattereString, "images");
System.out.println(maineString);
Output:
[img border=0]images/bbcode/sets/misc/bullet_go.png[/img]

how to read string upto certain comma with java

i need to read a file upto certain comma,for example;
String s=hii,lol,wow,and,finally
need output as hii,lol,wow,and
Dont want last comma followed with characters
As my code is reading last comma string
Example:iam getting my code out put as: finally
Below is my code
please guide me
File file =new File("C:/Users/xyz.txt");
FileInputStream inputStream = new FileInputStream(file);
String filke = IOUtils.toString(inputStream);
String[] pieces = filke.split("(?=,)");
String answer = Arrays.stream(pieces).skip(pieces.length - 1).collect(Collectors.joining());
String www=answer.substring(1);
System.out.format("Answer = \"%s\"%n", www);
You don't necessarily need to use regex for this. Just get the index of the last ',' and get the substring from 0 to that index:
String answer = "hii,lol,wow,and,finally";
String www = answer.substring(0, answer.lastIndexOf(','));
System.out.println(www); // prints hii,lol,wow,and
String in Java has a method called lastIndexOf(String str). That might come in handy for you.
Say your input is String s = "hii,lol,wow,and,finally";
You can do a String operation like:
String s = "hii,lol,wow,and,finally";
s = s.substring(0, s.lastIndexOf(","));
This gives you the output: hii,lol,wow,and
If you want to use java 8 stream to do it for you maybe try filter ?
String answer = Arrays.stream(pieces).filter(p -> !Objects.equals(p, pieces[pieces.length-1])).collect(Collectors.joining());
this will print Answer = "hii,lol,wow,and"
To have stricly regex you can use the Pattern.compile and Matcher
Pattern.compile("\w+(?=,)");
Matcher matcher = pattern.matcher(filke);
while (matcher.find()) {
System.out.println(matcher.group(1) + ","); // regex not good enough, maybe someone can edit it to include , (comma)
}
Will match hii, lol, wow, and,
See the regex example here https://regex101.com/r/1iZDjg/1

How to Extract text from given string?

I want to extract a perticular image path string from a given string .
The String is http:\localhost:9090\SpringMVC\images\integration-icon.png
Now i want to get only the path after images like
\images\integration-icon.png
i tried this
Pattern pattern = Pattern.compile("SpringMVC");
Matcher matcher = pattern.matcher(str);
System.out.println("Checking");
if (matcher.find()) {
System.out.println(matcher.group(1));
}
how can i get ?
String filename = filepath.substring(filepath.lastIndexOf("\\") + 1);
or (haven't tried and looks somewhat odd)
String filename = filepath.substring(filepath.lastIndexOf("\\", "images\\".length()) + 1);
String string = "http:\localhost:9090\ZenoBusinessStore\images\integration-icon.png";
int index = string.indexOf("images\\");
String output = string.substring(index);
String text = "http:\localhost:9090\SpringMVC\images\integration-icon.png"
String subText = text.subString(text.indexOf("\images"), text.length());
System.out.println(subText);
String in = "http:\\localhost:9090\\ZenoBusinessStore\\images\\integration-icon.png";
String op = in.replace("http:\\localhost:9090\\ZenoBusinessStore", "");
System.out.println(op);
ZenoBusinessStore must be the name of your project which is constant.
Now split the string
String s = "http:\localhost:9090\ZenoBusinessStore\images\integration-icon.png";
String ary = s.split("ZenoBusinessStore");
Now the 2nd element of the array is your image path.
System.out.println(ary[1]);
Use '\\'. It's because backslash is used in escape sequence like '\n'. With a single \ the compiler have no way to know.

substring between two delimiters

I have a string as : "This is a URL http://www.google.com/MyDoc.pdf which should be used"
I just need to extract the URL that is starting from http and ending at pdf :
http://www.google.com/MyDoc.pdf
String sLeftDelimiter = "http://";
String[] tempURL = sValueFromAddAtt.split(sLeftDelimiter );
String sRequiredURL = sLeftDelimiter + tempURL[1];
This gives me the output as "http://www.google.com/MyDoc.pdf which should be used"
Need help on this.
This kind of problem is what regular expressions were made for:
Pattern findUrl = Pattern.compile("\\bhttp.*?\\.pdf\\b");
Matcher matcher = findUrl.matcher("This is a URL http://www.google.com/MyDoc.pdf which should be used");
while (matcher.find()) {
System.out.println(matcher.group());
}
The regular expression explained:
\b before the "http" there is a word boundary (i.e. xhttp does not match)
http the string "http" (be aware that this also matches "https" and "httpsomething")
.*? any character (.) any number of times (*), but try to use the least amount of characters (?)
\.pdf the literal string ".pdf"
\b after the ".pdf" there is a word boundary (i.e. .pdfoo does not match)
If you would like to match only http and https, try to use this instead of http in your string:
https?\: - this matches the string http, then an optional "s" (indicated by the ? after the s) and then a colon.
why don't you use startsWith("http://") and endsWith(".pdf") mthods of String class.
Both the method returns boolean value, if both returns true, then your condition succeed else your condition is failed.
Try this
String StringName="This is a URL http://www.google.com/MyDoc.pdf which should be used";
StringName=StringName.substring(StringName.indexOf("http:"),StringName.indexOf("which"));
You can use Regular Expression power for here.
First you have to find Url in original string then remove other part.
Following code shows my suggestion:
String regex = "\\b(http|ftp|file)://[-a-zA-Z0-9+&##/%?=~_|!:,.;]*[-a-zA-Z0-9+&##/%=~_|]";
String str = "This is a URL http://www.google.com/MyDoc.pdf which should be used";
String[] splited = str.split(regex);
for(String current_part : splited)
{
str = str.replace(current_part, "");
}
System.out.println(str);
This snippet code cans retrieve any url in any string with any pattern.
You cant add customize protocol such as https to protocol part in above regular expression.
I hope my answer help you ;)
public static String getStringBetweenStrings(String aString, String aPattern1, String aPattern2) {
String ret = null;
int pos1,pos2;
pos1 = aString.indexOf(aPattern1) + aPattern1.length();
pos2 = aString.indexOf(aPattern2);
if ((pos1>0) && (pos2>0) && (pos2 > pos1)) {
return aString.substring(pos1, pos2);
}
return ret;
}
You can use String.replaceAll with a capturing group and back reference for a very concise solution:
String input = "This is a URL http://www.google.com/MyDoc.pdf which should be used";
System.out.println(input.replaceAll(".*(http.*?\\.pdf).*", "$1"));
Here's a breakdown for the regex: https://regexr.com/3qmus

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