Java compact1, compact2, compact3 java.util.regex Interface MatchResult（JDK8）

Method Detail

• start

  int start()

  Returns the start index of the match.

  Returns:

  The index of the first character matched

  Throws:

  IllegalStateException - If no match has yet been attempted, or if the previous match operation failed

• start

  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 - The index of a capturing group in this matcher's pattern

  Returns:

  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

• end

  int end()

  Returns the offset after the last character matched.

  Returns:

  The offset after the last character matched

  Throws:

  IllegalStateException - If no match has yet been attempted, or if the previous match operation failed

• end

  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 - The index of a capturing group in this matcher's pattern

  Returns:

  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

• group

  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:

  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

• group

  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 - The index of a capturing group in this matcher's pattern

  Returns:

  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

• groupCount

  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:

  The number of capturing groups in this matcher's pattern