java - Multi pattern string split -


i have text, consisting of varying regex delimiters, followed text. in example, have 3 regex delimiters (patterna, b, c), , text looks :

|..stringmatchinga..|..text1..|..stringmatchingb..|..text2..|..stringmatchinga..|..text3..|..stringmatchingc..|..text4..|

i looking efficient java solution extract information list of triplet :

  • {patterna, stringmatchinga, text1}
  • {patternb, stringmatchingb, text2}
  • {patterna, stringmatchinga, text3}
  • {patternc, stringmatchingc, text4}

with information, know each triplet, pattern has been matched, string has matched it.

for moment, have approach, guess far more efficient advanced regex usage ?

   string pattern = "?=(patterna|patternb|patternc)";    string()[] tokens = input.split(pattern);    for(string token : tokens)    {       //if start of token matches patterna ...       //elseif start of token matches pattern b...       //etc...      }

remarks :

  • patterns mutually exclusive.
  • string starts @ least 1 pattern.

you can use loop , inside code block can "eat" found @ beginning of text. in way @ every iteration parsing quite simple , maintenable/expandible.

the simple rule is: eat found , process it.

something 

string chunk; while(text.size() >0 {      chunk = eat(text,pattern1);     if (chunk.lengh()>0}{        ...        continue;     }     chunk = eat(text,pattern2);     if (chunk.lengh()>0}{        ...        continue;     }  }

for perfomance reason have compile regexp patterns before entering loop.

(consider using parser generator antlr).


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