Java Regular expression matching pattern [greedy type, reluctance type, possessive type]

Greediness (greedy type): Maximum match

X, x*, x+, X{n,} are the maximum matches. For example you want to use "<.+>" to match "A<tr>aava </tr>abb", perhaps the result you expect is to match "<tr>", but the actual result will match to "<tr>aava </ Tr>.

In the greediness mode, the match will be as large as possible until the entire content is matched, and when the match is found to be unsuccessful, the fallback narrowing the match until the match is successful

String test = "A<tr>aava </tr>abb"= "<.+>""# # #");

Output: a## #abb

Reluctant (laziness) (barely): Minimum match

X??、 x*, x+?, X{n,}? Is the minimum match, in fact x{n,m}? and X{n}? Some superfluous. Add after greediness mode? is the smallest match.

In reluctant mode, attempts to match a larger range of content are no longer attempted as long as the match succeeds

String test = "A<tr>aava </tr>abb"= "<.+?>""# # #");

Output: a## #aava # # #abb

Unlike greediness, the content is matched in reluctant mode two times

Possessive (possessive): Exact match

x?+, x*+, x + +, x{n,}+ are exact matches, and adding + after greediness mode is an exact match.

The possessive pattern has a certain similarity to greediness, which is to match the maximum range of content as much as possible until the content ends, but unlike greediness, the exact match no longer rolls back the attempt to match a smaller range.

String test = "A<tr>aava </tr>abb"= "<.++>"= "<tr>"= "<tr>" "###""###"));

Output: A<tr>aava </tr>abb

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Java Regular expression matching pattern [greedy type, reluctance type, possessive type]