Cannot convert result of opennlp Parse

Question

Im using opennlp's Parse model to parse a line of input, my code:

public void parse(String input){
InputStream modelIn = null;
try {
    modelIn = new FileInputStream("en-parser-chunking.bin");
  ParserModel model = new ParserModel(modelIn);
    opennlp.tools.parser.Parser parser = ParserFactory.create(model);
    opennlp.tools.parser.Parse topParses[] = ParserTool.parseLine(input, parser, 1);
for (opennlp.tools.parser.Parse p : topParses){
            p.show();

                         }
}catch (IOException e) {
  e.printStackTrace();
}finally {
  if (modelIn != null) {
    try {
      modelIn.close();
    }
    catch (IOException e) {
    }
  }
}
    }

if my input is this is a test line p.show displays (TOP (S (NP (DT this)) (VP (VBZ is) (NP (DT a) (NN test) (NN line))))) but p.toString displays this is a test line

how can i make it the same as p.show?

Answer 1

this works for me... you have to use the overloaded show, which internally updates the StringBuffer reference passed in

public void parse(String input){
InputStream modelIn = null;
try {
    modelIn = new FileInputStream("en-parser-chunking.bin");
  ParserModel model = new ParserModel(modelIn);
    opennlp.tools.parser.Parser parser = ParserFactory.create(model);
    opennlp.tools.parser.Parse topParses[] = ParserTool.parseLine(input, parser, 1);
    for (opennlp.tools.parser.Parse p : topParses){

      StringBuilder sb = new StringBuilder(input.length() * 4);
      p.show(sb);
      //sb now contains all the tags
      System.out.println(sb);

    }
}catch (IOException e) {
  e.printStackTrace();
}finally {
  if (modelIn != null) {
    try {
      modelIn.close();
    }
    catch (IOException e) {
    }
  }
}
} 

Answer 2

The solution to this question fails as reported by Greg. It fails because this line reads incorrectly:

StringBuilder sb = new StringBuilder(input.length() * 4);

In the OpenNLP toolkit the show() method in the Parse class cannot use a StringBuilder type:

The posted solution will work if the StringBuilder type is changed to a StringBuffer type:

StringBuffer sb = new StringBuffer(input.length() * 4);

See: https://opennlp.apache.org/docs/1.9.0/apidocs/opennlp-tools/opennlp/tools/parser/Parse.html#show-java.lang.StringBuffer-

show(StringBuffer sb) Appends the specified string buffer with a string representation of this parse.