I am working on a Java project and I am trying to get useDelimiter to remove everything except the text in between "=" and ",". For example, on the first line of the file I would like to keep "ThermostatNight".
This is what the text file looks like:
Event=ThermostatNight,time=0
Event=LightOn,time=2000
I've been able to do the exact opposite using this code:
s.useDelimiter("=(.*?),");
Is there any way I can tweak this to do the opposite?
Try this:
s.replaceAll("([a-zA-Z]*=)([a-zA-Z]*)(,.*)","$2")
This is following the pattern you show. If it changes you will have to change this regex.
See it here: http://regex101.com/r/jN8iR8
See the section Match groups, you will see that group 2 is your desired result.
The replace all method is replacing everything just for the group 2 which is what is in between = and ,
Edit
As the OP said that s is a Scanner
Scanner s = new Scanner(new File("YOURFILE"));
while (s.hasNext()) {
String text = s.next();
System.out.println( text.replaceAll("([a-zA-Z]*=)([a-zA-Z]*)(,.*)","$2") );
}
s.close();
Related
My text file has a pattern and it's just like the following:
1;Mary Yeah;John Freeman;(12)3456-7890;iammary#gmail.com
2;Ash Wilson;One Two Three;(99)1111-2222;lorddragon#hotmail.com
3;Xin Zhao;Street Address 55;(11)0101-0202;lolyourface#gmail.com
4;My Name;My Address;My Phone;myemail#mail.com
I want to be able to type the line number, the type of data I want to replace(e-mail, phone, name), and the string I want to replace them with. The program overwrites the text.
How could I code this in Java?
The issue of how to find a given row based on the line number depends on many things, most importantly it depends on code you haven't shown us. But as for what you can do once you have found a given line, you may try the following:
String line = "2;Ash Wilson;One Two Three;(99)1111-2222;lorddragon#hotmail.com";
String[] parts = line.split(";");
parts[4] = "some.address#mail.com"; // to change the email
// now join back to a single line
line = String.join(";", Arrays.asList(parts));
Demo
Input -
String ipXmlString = "<root>"
+ "<accntNoGrp><accntNo>1234567</accntNo></accntNoGrp>"
+ "<accntNoGrp><accntNo>6663823</accntNo></accntNoGrp>"
+ "</root>";
Tried follwing things using to mask values within using
String op = ipXmlString .replaceAll("<accntNo>(.+?)</accntNo>", "######");
But above code masks all the values
<root><accntNoGrp>######</accntNoGrp><accntNoGrp>######</accntNoGrp></root>
Expected Output:
<root><accntNoGrp><accntNo>#####67</accntNo></accntNoGrp><accntNoGrp><accntNo>#####23</accntNo></accntNoGrp></root>
How to achieve this using java regex ?Could someone help
Your replacement is wrong, you need to include the <accntNo> tag in the actual replacement. Also, it appears that you want to show the last two characters/numbers of the account number. In this case, we can capture this information during the match and use it in the replacement.
Code:
String op = ipXmlString.replaceAll("<accntNo>(?:.+?)(.{2})</accntNo>", "<accntNo>######$1</accntNo>");
Explanation:
<accntNo> match an opening tag
(?:.+?) match, but do not capture, anything up until the first
(.{2}) two characters before closing tag (and capture this)
</accntNo> match a closing tag
Note here that by using ?: inside a parenthesis in the pattern, we tell the regex engine to not capture it. There is no point in capturing anything before the last two characters of the account number because we don't want to us it.
The $1 quantity in the replacement refers to the first capture group. In this case, it is the last two characters of the account number. Hence, we build the replacement string you want this way.
Demo here:
Rextester
Try this code:
public static void main(String[] args) {
String ipXmlString = "<root>"
+ "<accntNoGrp><accntNo>1234567</accntNo></accntNoGrp>"
+ "<accntNoGrp><accntNo>6663823</accntNo></accntNoGrp>"
+ "</root>";
String replaceAll = ipXmlString.replaceAll("\\d+", "######");
System.out.println(replaceAll);
}
Prints:
<root><accntNoGrp><accntNo>######</accntNo></accntNoGrp><accntNoGrp><accntNo>######</accntNo></accntNoGrp></root>
I'm a newcomer to Java trying to submit a working project, in this instance printDuplicates. The instructions are as follows:
Write a method named printDuplicates that accepts as its parameter a Scanner for an input file containing a series of lines. Your method should examine each line looking for consecutive occurrences of the same token on the same line and print each duplicated token along how many times it appears consecutively. Non-repeated tokens are not printed. Repetition across multiple lines (such as if a line ends with a given token and the next line starts with the same token) is not considered in this problem.
For example, if the input file contains the following text:
hello how how are you you you you
I I I am Jack's Jack's smirking smirking smirking smirking smirking revenge
bow wow wow yippee yippee yo yippee yippee yay yay yay
one fish two fish red fish blue fish
It's the Muppet Show, wakka wakka wakka
Your method would produce the following output for the preceding input file:
how*2 you*4
I*3 Jack's*2 smirking*5
wow*2 yippee*2 yippee*2 yay*3
wakka*3
Your code prints only the repeated tokens; the ones that only appear once in a row are not shown. Your code should place a single space between each reported duplicate token and should respect the line breaks in the original file. This is why a blank line appears in the expected output, corresponding to the fourth line of the file that did not contain any consecutively duplicated tokens. You may assume that each line of the file contains at least 1 token of input.
Here is my code, pretty much ready for submitting.
import java.io.*;
import java.util.*;
Scanner input;
public static void printDuplicates(Scanner input) throws Exception {
String word = "";
String word2 = "";
input = new Scanner(new File("idontknowwhattodo.txt"));
while(input.hasNextLine()) {
Scanner line = new Scanner(input.nextLine());
int repeat = 1;
word = line.next();
while(line.hasNext()) {
word2 = line.next();
while(word.equals(word2)) {
repeat++;
if(line.hasNext()){
word2 = line.next();
} else {
break;
}
}
if(repeat!=1) {
System.out.print(word + "*" + repeat + " ");
}
repeat = 1;
word = word2;
}
System.out.println();
}
}
However, whenever I try to submit my project, it throws back this error:
(no output was produced!)
SecurityException on line 5:
You are not allowed to read the file /usr/share/tomcat7/temp/idontknowwhattodo.txt
java.lang.SecurityException: You are not allowed to read the file /usr/share/tomcat7/temp/idontknowwhattodo.txt
at java.io.FileInputStream.<init>(FileInputStream.java:135)
at java.io.FileReader.<init>(FileReader.java:72)
at Scanner.<init>(Scanner.java:330)
at printDuplicates (Line 5)
What does this mean? I have multiple working projects but I can't seem to submit them due to this one error. Any experts that can help me on this one? Thank you.
It looks like you are using Tomcat from your path. Tomcat requires special security permission to read or write files. This is a basic protection to prevent malicious code from accessing sensitive files on the OS. You can configure these directories or stick to reading and writing to the default ones:
https://tomcat.apache.org/tomcat-7.0-doc/security-manager-howto.html
Unable to add a comment because of reputation points so using the Answers section.
Agree with above comments, it is related to permissions.
Do an ls -ltr on /usr/share/tomcat7/temp/idontknowwhattodo.txt
Check whether the user (say myuser) with which you are running you java application has necessary permissions for /usr/share/tomcat7/temp/idontknowwhattodo.txt.
Two options below:
Give the user "myuser" the necessary permissions to the idontknowwhattodo.txt using chmod.
Or copy idontknowwhattodo.txt to a location where "myuser" has the permissions.
Problem description says that you're getting Scanner object as parameter. You don't have to recreate it, you're probably trying to submit your project to some online competition. Program on the server will load your class and call the method printDuplicates() with Scanner object as parameter, you don't have to worry about how it gets created. Just use it, and everything would be fine.
Just comment the scanner assignment line as below
String word = "";
String word2 = "";
/*input = new Scanner(new File("idontknowwhattodo.txt"));*/
while(input.hasNextLine()) {
...
As per instructions, you are already getting the Scanner object(which references the input file) as parameter to your method. So, you should not be re-initializing it.
This line should be removed:
input = new Scanner(new File("idontknowwhattodo.txt"));
I have a problem in getting the correct Regular expression.I have below xml as string
<user_input>
<UserInput Question="test Q?" Answer=<value>0</value><sam#testmail.com>"
</user_input>
Now I need to remove the xml character from Answer attribute only.
So I need the below:-
<user_input>
<UserInput Question="test Q?" Answer=value0value sam#testmail.com"
</user_input>
I have tried the below regex but did not worked out:-
str1.replaceAll("Answer=.*?<([^<]*)>", "$1");
its removing all the text before..
Can anyone help please?
You need to put ? within the first group to make it none greedy, also you dont need Answer=.*?:
str1.replaceAll("<([^<]*?)>", "$1")
DEMO
httpRequest.send("msg="+data+"&TC="+TC); try like this
Although variable width look-behinds are not supported in Java, you can work around it with .{0,1000} that should suffice.
Please check out this approach using 2 regexes, or 1 regex and 1 replace. Choose the one that suits best (I removed the \n line break from the first input string to show the flaw with using simple replace):
String input = "<user_input><UserInput Question=\"test Q?\" Answer=<value>0</value><sam#testmail.com>\"\n</user_input>";
String st = input.replace("><", " ").replaceAll("(?<=Answer=.{0,1000})[<>/]+(?=[^\"]*\")", "");
String st1 = input.replaceAll("(?<=Answer=.{0,1000})><(?=[^\"]*\")", " ").replaceAll("(?<=Answer=.{0,1000})[<>/]+(?=[^\"]*\")", "");
System.out.println(st + "\n" + st1);
Output of a sample program:
<user_input UserInput Question="test Q?" Answer=value0value sam#testmail.com"
</user_input>
<user_input><UserInput Question="test Q?" Answer=value0value sam#testmail.com"
</user_input>
First off, in your sample above, there is a trailing " after the email and > which I do not know if it was placed by error.
However, I will keep it there as according to your expected result, you need it to still be present.
This is my hack.
(Answer=)(<)(value)(>)(.+?([^<]*))(</)(value)(><)(.+?([^>]*))(>) to replace it with
$1$3$5$8 $10
The explanation...
(Answer=)(<)(value)(>) matches from Answer to the start of the value 0
(.+?([^<]*) matches the result from 0 or more right to the beginning < which starts the closing value tag
(</) here, I still select this since it was dropped in the previous expression
(><) I will later replace this with a space
(.+?([^>]*) This matches from the start of the email and excludes the > after the .com
(>) this one selects the last > which I will later drop when replacing.
The trailing " is not selected as I will rather not touch it as requested.
I am not posting any code I am struck with. I am trying this in Java:
Issue:
I have words like:
,xxxx-1223
yyyyy,xxdd-345
$,xxxxr-7
sdsdsdd-18
so what ever format I have I should be able to read the last one:
xxxx-1223
xxdd-345
xxxxr-7
sdsdsdd-18
what so may be the words, all I need to to get the words as shown.
Use String#lastIndexOf(int) to find where the last comma occurs, and use String#substring(int) to get the rest of the string that follows.
String input = /* whatever */;
int lastComma = input.lastIndexOf(',');
String output = input.substring(lastComma + 1);
String[] str=yourWord.split(",");
String output=str[str.length-1];
You can use this Regex: -
(\\w+-\\d+)$
Or this specific problem can simply be solved using String.split() or String.substring(int) methods