I am using FileUtils from apache commons.io to search text between two strings in a file with the following code:
Pattern p = Pattern.compile(Pattern.quote(fromDate) + "(.*?)" + Pattern.quote(toDate));
try {
Matcher m = p.matcher(fileContent);
while (m.find()) {
System.out.println(m.group(1));
But there is an error it is giving output only when both the strings lie in same line, no output if strings are in at different lines? Here i am taking the content of whole file into a Sting Varibale "fileContent".
The dot won't search over multiple lines. You need to give a second parameter for this Pattern.DOTALL like so:
Pattern p = Pattern.compile(Pattern.quote(fromDate) + "(.*?)" + Pattern.quote(toDate), Pattern.DOTALL);
Also this topics has some good explanation how it works: Match multiline text using regular expression
try ending the regex with ?s so you new regex should be:
"(.*?s)"
In most case the matcher stops evaluate expression when it encounters a line feed \n.
?s make the matcher pass the \n when it try to match the regex.
Related
I have htmlBody field which has html of a web page assigned to it. I want to check for all occurences for relative links ending in .html and for each of them to remove their extension. I do not want htmlBody.replaceAll(".html", "") because it will remove for all links and break some external links so my approach is to find all occurences that matches regex, and for each occurence to remove their extension using replaceAll() and append to sb. I tried to follow the example from official documentation but apparently it does not change any link, what could be the problem?
StringBuilder sb = new StringBuilder();
Pattern p = Pattern.compile("^\\/(.+\\\\)*(.+).(html)$");
Matcher m = p.matcher(htmlBody);
while (m.find()) {
String updatedLink = m.group().replaceAll(".html", "");
m.appendReplacement(sb, updatedLink);
}
m.appendTail(sb);
your regex was wrong, ^ match start of string, $ match end of string.
so matcher in your code will never match.
right regex like Pattern p = Pattern.compile("['\"]\\/(.+\\\\)*(.+).(html)");
but, it can't match <a href=/a.html>
I have this text from file which I would like to get values using pattern match:
<!--
#author: batman
#description: 100000
-->
I'm using this code to find comments into XML files and get values using Patterns match:
XMLStreamReader xr = XMLInputFactory.newInstance().createXMLStreamReader(new FileInputStream(file));
Pattern pattern = Pattern.compile("#(?<key>([\\w]+)?): (?<value>(.+)?)");
while (xr.hasNext())
{
if (xr.next() == XMLStreamConstants.COMMENT) {
String comment = xr.getText();
Matcher matcher = pattern.matcher(comment);
if(!matcher.matches()){
continue;
}
.....
}
When I run the code I get error:
persistence-configuration.xsd (No such file or directory)
at [row,col {unknown-source}]: [4,69]
But when I remove matcher.matches() I get several iterations if xr because I have several comments into XML file.
The idea is to get only the comment with the proper match and to skip the rest of the comments. Do you know why the code is not working fine?
I tried also with "#(?<key>[\\w]+): (?<value>.*)" but again I get the same issue.
Is you input source actually there? The exception you get hints at a file problem.
Matcher.matches() tests a String for complete confirmity with the entire pattern. All characters of the input sequence need to be consumed. So if your line starts with blanks (tabs, whitespaces...) then your matcher may fail to match, if you use matches.
You are looking for matcher.find(), which can be used like this:
Pattern myPattern = Pattern.compile("somePattern");
Matcher matcher = pattern.matcher("someInput");
while (matcher.find()) {
// this is where you can check what you found...
}
Besides, you may want to check, at what chunks the stream provides elements. Are they really coming linewise?
I went through a couple of examples to replace a given sub-string from a given string with "" but could not achieve the result. The String is too long to post and it contains a sub-string which is as follows:-
/image/journal/article?img_id=24810&t=1475128689597
I want to replace this sub-string with "".Here the value of img_id and t can vary, so I would have to use regular expression. I tried with the following code:-
String regex="^/image/journal/article?img_id=([0-9])*&t=([0-9])*$";
content=content.replace(regex,"");
Here content is the original given string. But this code is actually not replacing anything from the content. So please help..any help would be appreciated .thanx in advance.
Use replaceAll works in nice way with regex
content=content.replaceAll("[0-9]*","");
Code
String content="/image/journal/article?img_id=24810&t=1475128689597";
content=content.replaceAll("[0-9]*","");
System.out.println(content);
Output :
/image/journal/article?img_id=&t=
Update : simple, might be little less cozy but easy one
String content="sas/image/journal/article?img_id=24810&t=1475128689597";
content=content.replaceAll("\\/image.*","");
System.out.println(content);
Output:
sas
If there is something more after t=1475128689597/?tag=343sdds and you want to retain ?tag=343sdds then use below
String content="sas/image/journal/article?img_id=24810&t=1475128689597/?tag=343sdds";
content=content.replaceAll("(\\/image.*[0-9]+[\\/])","");
System.out.println(content);
}
Output:
sas?tag=343sdds
If you're trying to replace the substring of the URL with two quotations like so:
/image/journal/article?img_id=""&t=""
Then you need to add escaped quotes \"\" inside your content assignment, edit your regex to only look for the numbers, and change it to replaceAll:
content=content.replaceAll(regex,"\"\"");
You can use Java regex Utility to replace your String with "" or (any desired String literal), based on given pattern (regex) as following:
String content = "ALPHA_/image/journal/article?img_id=24810&t=1475128689597_BRAVO";
String regex = "\\/image\\/journal\\/article\\?img_id=\\d+&t=\\d+";
Pattern pattern = Pattern.compile(regex);
Matcher matcher = pattern.matcher(content);
if (matcher.find()) {
String replacement = matcher.replaceAll("PK");
System.out.println(replacement); // Will print ALPHA_PK_BRAVO
}
I am trying to extract image url from inside of a string. I am using Pattern and Matcher. I am using a regular expression to match the same. Whenever I am trying to debug the code, both, matcher.matches() and matcher.find() result into false.
I am attaching the image url and regular expression as well as my code.
Pattern pattern_name;
Matcher matcher_name;
String regex = "(http(s?):/)(/[^/]+)+\" + \"\\.(?:jpg|gif|png)";
String url = "http://www.medivision360.com/pharma/pages/articleImg/thumbnail/thumb3756d839adc5da3.jpg";
pattern_name = Pattern.compile(regex);
matcher_name = pattern_name.matcher(url);
matcher_name.matches();
matcher_name.find();
You seem to have some issue with the regex, the \" + \" should come from some code you mistook for a regex. That subpattern requires a quote, one or more spaces, then a space, and another double quote to appear right before the extension. It matches something like http://www.medivision360.com/pharma/pages/articleImg/thumbnail/thumb3756d839adc5da3" ".jpg.
Also, there are two redundant capture groups at the beginning, you do not need to use them.
Use
String regex = "https?:/(?:/[^/]+)+\\.(?:jpg|gif|png)";
See this demo
Java demo:
String rx = "https?:/(?:/[^/]+)+\\.(?:jpg|gif|png)";
String url = "http://www.medivision360.com/pharma/pages/articleImg/thumbnail/thumb3756d839adc5da3.jpg";
Pattern pat = Pattern.compile(rx);
Matcher matcher = pat.matcher(url);
if (matcher.matches()) {
System.out.println(matcher.group());
}
Note that Matcher#matches() requires a full string match, while Matcher#find() will find a partial match, a match inside a larger string.
You've escaped the double quotes in the string catenation
so the regex engine sees this (http(s?):/)(/[^/]+)+" + "\.(?:jpg|gif|png)
after c++ parses the string.
You can un-escape it "(http(s?):/)(/[^/]+)+" + "\\.(?:jpg|gif|png)"
or just join them together "(http(s?):/)(/[^/]+)+\\.(?:jpg|gif|png)"
If the expression is always at the end, I would suggest:
([^/?]+)(?=/?(?:$|\?))
I have a program that stores the version number in a text file on the file system. I import the file within java and I am wanting to extract the version number. I'm not very good with regex so I am hoping someone can help.
The text file looks like such:
0=2.2.5 BUILD (tons of other junk here)
I am wanting to extract 2.2.5. Nothing else. Can someone help me with the regex for this?
If you know the structure, you don't need a regex:
String line = "0=2.2.5 BUILD (tons of other junk here)";
String versionNumber = line.split(" ", 2)[0].substring(2);
This regular expression should do the trick:
(?<==)\d+\.\d+\.\d+(?=\s*BUILD)
Trying it out:
String s = "0=2.2.5 BUILD (tons of other junk here)";
Pattern p = Pattern.compile("(?<==)\\d+\\.\\d+\\.\\d+(?=\\s*BUILD)");
Matcher m = p.matcher(s);
while (m.find())
System.out.println(m.group());
2.2.5
Also if you are really looking for a regex, though there are definitely many ways to do this.
String line = "0=2.2.5 BUILD (tons of other junk here)";
Matcher matcher = Pattern.compile("^\\d+=((\\d|\\.)+)").matcher(line);
if (matcher.find())
System.out.println(matcher.group(1));
Output:
2.2.5
There are many ways to do this. Here is one of them
String data = "0=2.2.5 BUILD (tons of other junk here)";
Matcher m = Pattern.compile("\\d+=(\\d+([.]\\d+)+) BUILD").matcher(data);
if (m.find())
System.out.println(m.group(1));
If you are sure that data contains version number then you can also
System.out.println(data.substring(data.indexOf('=')+1,data.indexOf(' ')));