MatchResult
public
interface
MatchResult
| java.util.regex.MatchResult |
The result of a match operation.
This interface contains query methods used to determine the
results of a match against a regular expression. The match boundaries,
groups and group boundaries can be seen but not modified through
a MatchResult.
See also:
Summary
Public methods | |
|---|---|
abstract
int
|
end(int group)
Returns the offset after the last character of the subsequence captured by the given group during this match. |
abstract
int
|
end()
Returns the offset after the last character matched. |
abstract
String
|
group(int group)
Returns the input subsequence captured by the given group during the previous match operation. |
abstract
String
|
group()
Returns the input subsequence matched by the previous match. |
abstract
int
|
groupCount()
Returns the number of capturing groups in this match result's pattern. |
abstract
int
|
start()
Returns the start index of the match. |
abstract
int
|
start(int group)
Returns the start index of the subsequence captured by the given group during this match. |
Public methods
end
public abstract int end (int group)
Returns the offset after the last character of the subsequence captured by the given group during this match.
Capturing groups are indexed from left
to right, starting at one. Group zero denotes the entire pattern, so
the expression m.end(0) is equivalent to
m.end().
| Parameters | |
|---|---|
group |
int: The index of a capturing group in this matcher's pattern |
| Returns | |
|---|---|
int |
The offset after the last character captured by the group,
or -1 if the match was successful
but the group itself did not match anything |
| Throws | |
|---|---|
IllegalStateException |
If no match has yet been attempted, or if the previous match operation failed |
IndexOutOfBoundsException |
If there is no capturing group in the pattern with the given index |
end
public abstract int end ()
Returns the offset after the last character matched.
| Returns | |
|---|---|
int |
The offset after the last character matched |
| Throws | |
|---|---|
IllegalStateException |
If no match has yet been attempted, or if the previous match operation failed |
group
public abstract String group (int group)
Returns the input subsequence captured by the given group during the previous match operation.
For a matcher m, input sequence s, and group index
g, the expressions m.group(g) and
s.substring(m.start(g), m.end(g))
are equivalent.
Capturing groups are indexed from left
to right, starting at one. Group zero denotes the entire pattern, so
the expression m.group(0) is equivalent to m.group().
If the match was successful but the group specified failed to match
any part of the input sequence, then null is returned. Note
that some groups, for example (a*), match the empty string.
This method will return the empty string when such a group successfully
matches the empty string in the input.
| Parameters | |
|---|---|
group |
int: The index of a capturing group in this matcher's pattern |
| Returns | |
|---|---|
String |
The (possibly empty) subsequence captured by the group
during the previous match, or null if the group
failed to match part of the input |
| Throws | |
|---|---|
IllegalStateException |
If no match has yet been attempted, or if the previous match operation failed |
IndexOutOfBoundsException |
If there is no capturing group in the pattern with the given index |
group
public abstract String group ()
Returns the input subsequence matched by the previous match.
For a matcher m with input sequence s,
the expressions m.group() and
s.substring(m.start(), m.end())
are equivalent.
Note that some patterns, for example a*, match the empty
string. This method will return the empty string when the pattern
successfully matches the empty string in the input.
| Returns | |
|---|---|
String |
The (possibly empty) subsequence matched by the previous match, in string form |
| Throws | |
|---|---|
IllegalStateException |
If no match has yet been attempted, or if the previous match operation failed |
groupCount
public abstract int groupCount ()
Returns the number of capturing groups in this match result's pattern.
Group zero denotes the entire pattern by convention. It is not included in this count.
Any non-negative integer smaller than or equal to the value returned by this method is guaranteed to be a valid group index for this matcher.
| Returns | |
|---|---|
int |
The number of capturing groups in this matcher's pattern |
start
public abstract int start ()
Returns the start index of the match.
| Returns | |
|---|---|
int |
The index of the first character matched |
| Throws | |
|---|---|
IllegalStateException |
If no match has yet been attempted, or if the previous match operation failed |
start
public abstract int start (int group)
Returns the start index of the subsequence captured by the given group during this match.
Capturing groups are indexed from left
to right, starting at one. Group zero denotes the entire pattern, so
the expression m.start(0) is equivalent to
m.start().
| Parameters | |
|---|---|
group |
int: The index of a capturing group in this matcher's pattern |
| Returns | |
|---|---|
int |
The index of the first character captured by the group,
or -1 if the match was successful but the group
itself did not match anything |
| Throws | |
|---|---|
IllegalStateException |
If no match has yet been attempted, or if the previous match operation failed |
IndexOutOfBoundsException |
If there is no capturing group in the pattern with the given index |