需要 java 正则表达式从特定字符串中删除/替换 XML 元素

Question

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?

Answer 1

You need to put ? within the first group to make it none greedy, also you dont need Answer=.*? :

str1.replaceAll("<([^<]*?)>", "$1")

DEMO

Answer 2

httpRequest.send("msg="+data+"&TC="+TC); try like this

Answer 3

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>  

Answer 4

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.