在Java中定义模式从json字符串中提取多个日期的问题

Question

I have the following code:

    public static void main(String[] args) {
    String str = "{\"$and\":[{\\\"$or\\\":[{\\\"origen\\\":{\\\"$eq\\\":\\\"LEMD\\\"}},{\\\"origen\\\":{\\\"$eq\\\":\\\"LEBL\\\"}}]},{\"horasacta\":{\"$gte\":\"28/02/2015 00:00:00\"}},{\"horasacta\":{\"$lte\":\"28/02/2015 23:59:59\"}}]}";

    Pattern pattern = Pattern.compile("\\{\"(.*?)\":\\{\"\\$(.*?)\":\"[0-9]+/[0-9]+/[0-9]+ [0-9]+:[0-9]+:[0-9]+\"}}");
    Matcher matcher = pattern.matcher(str);
    while (matcher.find()) {
        System.out.println(matcher.group(0));
    }

I want to get the substrings:

{\"departure\":{\"$gte\":\"28/02/2015 00:00:00\"}}
{\"departure\":{\"$lte\":\"28/02/2015 23:59:59\"}}

but the program give me:

{"$and":[{\"$or\":[{\"origin\":{\"$eq\":\"LEMD\"}},{\"origin\":{\"$eq\":\"LEBL\"}}]},{"departure":{"$gte":"28/02/2015 00:00:00"}}
{"departure":{"$lte":"28/02/2015 23:59:59"}}

the 2nd time the find() matches the pattern but the 1st time it doesn't do the job.

Any help?

thanks

Answer 1

It's frowned upon, yet if you have to, I'm guessing that you may be trying to write an expression looking somewhat like:

{\\"([^\\]+)\\":{\\"\$([^\\]+)\\":\\"[0-9]+\/[0-9]+\/[0-9]+\s+[0-9]+:[0-9]+:[0-9]+\\"}}

not so sure though.

---

The expression is explained on the top right panel of regex101.com , if you wish to explore/simplify/modify it, and in this link , you can watch how it would match against some sample inputs, if you like.

Test

import java.util.regex.Matcher;
import java.util.regex.Pattern;

final String regex = "\\{\\\\\"([^\\\\]+)\\\\\":\\{\\\\\"\\$([^\\\\]+)\\\\\":\\\\\"[0-9]+\\/[0-9]+\\/[0-9]+\\s+[0-9]+:[0-9]+:[0-9]+\\\\\"\\}}";
final String string = "{\\\"departure\\\":{\\\"$gte\\\":\\\"28/02/2015 00:00:00\\\"}}\n"
     + "{\\\"departure\\\":{\\\"$lte\\\":\\\"28/02/2015 23:59:59\\\"}}";

final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE);
final Matcher matcher = pattern.matcher(string);

while (matcher.find()) {
    System.out.println("Full match: " + matcher.group(0));
    for (int i = 1; i <= matcher.groupCount(); i++) {
        System.out.println("Group " + i + ": " + matcher.group(i));
    }
}