Click here to watch on Youtube :
https://www.youtube.com/watch?v=cfNT_tqODRY&list=UUhwKlOVR041tngjerWxVccw
RegexDemo.java
import java.util.regex.Matcher;
import java.util.regex.Pattern;
/**
*
* This example searches the text for occurrences of the word John.
* For each match found, group number 1 is extracted, which is what
* matched the group marked with parentheses.
*
*/
public class RegexDemo
{
public static void main(String[] args)
{
String text = "John writes about this, and John writes about that,"
+ " and John writes about everything. ";
/*
* Groups are marked with parentheses in the regular
* expression.
*
* This regular expression matches the text John. The
* parentheses are not part of the text that is matched. The
* parentheses mark a group. When a match is found in a text,
* you can get access to the part of the regular expression
* inside the group.
*/
String regex = "(John)";
Pattern pattern = Pattern.compile(regex);
Matcher matcher = pattern.matcher(text);
while (matcher.find())
{
/*
* We access a group using the group(int groupNo) method.
* A regular expression can have more than one group. Each
* group is thus marked with a separate set of
* parentheses. To get access to the text that matched the
* subpart of the expression in a specific group, pass the
* number of the group to the group(int groupNo) method.
*
* The group with number 0 is always the whole regular
* expression. To get access to a group marked by
* parentheses you should start with group numbers 1.
*/
System.out.println("found: " + matcher.group(1) + " , start: "
+ matcher.start() + ", end: " + matcher.end());
}
}
}
import java.util.regex.Pattern;
/**
*
* This example searches the text for occurrences of the word John.
* For each match found, group number 1 is extracted, which is what
* matched the group marked with parentheses.
*
*/
public class RegexDemo
{
public static void main(String[] args)
{
String text = "John writes about this, and John writes about that,"
+ " and John writes about everything. ";
/*
* Groups are marked with parentheses in the regular
* expression.
*
* This regular expression matches the text John. The
* parentheses are not part of the text that is matched. The
* parentheses mark a group. When a match is found in a text,
* you can get access to the part of the regular expression
* inside the group.
*/
String regex = "(John)";
Pattern pattern = Pattern.compile(regex);
Matcher matcher = pattern.matcher(text);
while (matcher.find())
{
/*
* We access a group using the group(int groupNo) method.
* A regular expression can have more than one group. Each
* group is thus marked with a separate set of
* parentheses. To get access to the text that matched the
* subpart of the expression in a specific group, pass the
* number of the group to the group(int groupNo) method.
*
* The group with number 0 is always the whole regular
* expression. To get access to a group marked by
* parentheses you should start with group numbers 1.
*/
System.out.println("found: " + matcher.group(1) + " , start: "
+ matcher.start() + ", end: " + matcher.end());
}
}
}
Output
found: John , start: 0, end: 4
found: John , start: 28, end: 32
found: John , start: 56, end: 60
found: John , start: 28, end: 32
found: John , start: 56, end: 60
Click the below link to download the code:
https://sites.google.com/site/ramj2eev1/home/javabasics/RegexDemo_group_john.zip?attredirects=0&d=1
Github Link:
https://github.com/ramram43210/Java/tree/master/BasicJava/RegexDemo_group_john
Bitbucket Link:
https://bitbucket.org/ramram43210/java/src/57d5e7f2c5fabff367c40b36a92925e1158e7f5a/BasicJava/RegexDemo_group_john/?at=master
See also:
No comments:
Post a Comment