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Stanford Parser processes raw text in English, Chinese, German, Arabic, and French, and extracts constituency parse trees.

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package edu.stanford.nlp.ling.tokensregex;

import edu.stanford.nlp.util.Interval;

import java.util.Collection;
import java.util.List;

/**
 * Matches potentially multiple node (i.e does match across multiple tokens)
 *
 * @author Angel Chang
 */
public abstract class MultiNodePattern {
  int minNodes = 1;
  int maxNodes = -1;   // Set the max number of nodes this pattern can match 


  /**
   * Tries to match sequence of nodes starting of start
   * Returns intervals (token offsets) of when the nodes matches
   * @param nodes
   * @param start
   */
  protected abstract Collection> match(List nodes, int start);

  public int getMinNodes() {
    return minNodes;
  }

  public void setMinNodes(int minNodes) {
    this.minNodes = minNodes;
  }

  public int getMaxNodes() {
    return maxNodes;
  }

  public void setMaxNodes(int maxNodes) {
    this.maxNodes = maxNodes;
  }

  protected static class IntersectMultiNodePattern extends MultiNodePattern {
    List> nodePatterns;

    protected IntersectMultiNodePattern(List> nodePatterns) {
      this.nodePatterns = nodePatterns;
    }

    protected Collection> match(List nodes, int start)
    {
      Collection> matched = null;
      for (MultiNodePattern p:nodePatterns) {
        Collection> m = p.match(nodes, start);
        if (m == null || m.size() == 0) {
          return null;
        }
        if (matched == null) {
          matched = m;
        } else {
          matched.retainAll(m);
          if (m.size() == 0) {
            return null;
          }
        }
      }
      return matched;
    }
  }

  protected static class UnionMultiNodePattern extends MultiNodePattern {
    List> nodePatterns;

    protected UnionMultiNodePattern(List> nodePatterns) {
      this.nodePatterns = nodePatterns;
    }

    protected Collection> match(List nodes, int start)
    {
      Collection> matched = null;
      for (MultiNodePattern p:nodePatterns) {
        Collection> m = p.match(nodes, start);
        if (m != null && m.size() > 0) {
          if (matched == null) {
            matched = m;
          } else {
            for (Interval i:m) {
              if (!matched.contains(i)) {
                matched.add(i);
              }
            }
          }
        }
      }
      return matched;
    }
  }

}