    001    package org.maltparser.core.syntaxgraph.headrules;
    002
    003    import java.io.BufferedReader;
    004    import java.io.IOException;
    005    import java.io.InputStreamReader;
    006    import java.net.URL;
    007
    008    import org.apache.log4j.Logger;
    009    import org.maltparser.core.exception.MaltChainedException;
    010    import org.maltparser.core.helper.HashMap;
    011    import org.maltparser.core.helper.Util;
    012    import org.maltparser.core.io.dataformat.DataFormatInstance;
    013    import org.maltparser.core.symbol.SymbolTable;
    014    import org.maltparser.core.syntaxgraph.node.NonTerminalNode;
    015    import org.maltparser.core.syntaxgraph.node.PhraseStructureNode;
    016
    017    /**
    018    *
    019    *
    020    * @author Johan Hall
    021    */
    022    public class HeadRules extends HashMap<String,HeadRule> {
    023            public static final long serialVersionUID = 8045568022124826323L;
    024            protected Logger logger;
    025            protected String name;
    026            protected DataFormatInstance dataFormatInstance;
    027            protected SymbolTable nonTerminalSymbolTable; // TODO more complex
    028            protected SymbolTable edgelabelSymbolTable; // TODO more complex
    029
    030            public HeadRules(Logger logger, DataFormatInstance dataFormatInstance) throws MaltChainedException {
    031                    setLogger(logger);
    032                    setDataFormatInstance(dataFormatInstance);
    033                    nonTerminalSymbolTable = dataFormatInstance.getSymbolTables().addSymbolTable("CAT");
    034                    edgelabelSymbolTable = dataFormatInstance.getSymbolTables().addSymbolTable("LABEL");
    035            }
    036
    037            public void parseHeadRules(String fileName) throws MaltChainedException {
    038                    parseHeadRules(Util.findURL(fileName));
    039            }
    040
    041            public void parseHeadRules(URL url) throws MaltChainedException {
    042                    BufferedReader br = null;
    043                    try {
    044                            br = new BufferedReader(new InputStreamReader(url.openStream()));
    045                    } catch (IOException e) {
    046                            throw new HeadRuleException("Could not read the head rules from file '"+url.toString()+"'. ", e);
    047                    }
    048                    if (logger.isInfoEnabled()) {
    049                            logger.debug("Loading the head rule specification '"+url.toString()+"' ...\n");
    050                    }
    051                    String fileLine;
    052                    while (true) {
    053                            try {
    054                                    fileLine = br.readLine();
    055                            } catch (IOException e) {
    056                                    throw new HeadRuleException("Could not read the head rules from file '"+url.toString()+"'. ", e);
    057                            }
    058                            if (fileLine == null) {
    059                                    break;
    060                            }
    061                            if (fileLine.length() <= 1 && fileLine.trim().substring(0, 2).trim().equals("--")) {
    062                                    continue;
    063                            }
    064                            int index = fileLine.indexOf('\t');
    065                            if (index == -1) {
    066                                    throw new HeadRuleException("The specification of the head rule is not correct '"+fileLine+"'. ");
    067                            }
    068
    069                            HeadRule rule = new HeadRule(this, fileLine);
    070                            put(fileLine.substring(0,index), rule);
    071                    }
    072            }
    073
    074            public PhraseStructureNode getHeadChild(NonTerminalNode nt) throws MaltChainedException {
    075                    HeadRule rule = null;
    076                    if (nt.hasLabel(nonTerminalSymbolTable)) {
    077                            rule = this.get(nonTerminalSymbolTable.getName()+":"+nt.getLabelSymbol(nonTerminalSymbolTable));
    078                    }
    079                    if (rule == null && nt.hasParentEdgeLabel(edgelabelSymbolTable)) {
    080                            rule = this.get(edgelabelSymbolTable.getName()+":"+nt.getParentEdgeLabelSymbol(edgelabelSymbolTable));
    081                    }
    082
    083                    if (rule != null) {
    084                            return rule.getHeadChild(nt);
    085                    }
    086                    return null;
    087            }
    088
    089            public Direction getDefaultDirection(NonTerminalNode nt) throws MaltChainedException {
    090                    HeadRule rule = null;
    091                    if (nt.hasLabel(nonTerminalSymbolTable)) {
    092                            rule = this.get(nonTerminalSymbolTable.getName()+":"+nt.getLabelSymbol(nonTerminalSymbolTable));
    093                    }
    094                    if (rule == null && nt.hasParentEdgeLabel(edgelabelSymbolTable)) {
    095                            rule = this.get(edgelabelSymbolTable.getName()+":"+nt.getParentEdgeLabelSymbol(edgelabelSymbolTable));
    096                    }
    097
    098                    if (rule != null) {
    099                            return rule.getDefaultDirection();
    100                    }
    101                    return Direction.LEFT;
    102            }
    103
    104            public Logger getLogger() {
    105                    return logger;
    106            }
    107
    108            public void setLogger(Logger logger) {
    109                    this.logger = logger;
    110            }
    111
    112            public DataFormatInstance getDataFormatInstance() {
    113                    return dataFormatInstance;
    114            }
    115
    116            public void setDataFormatInstance(DataFormatInstance dataFormatInstance) {
    117                    this.dataFormatInstance = dataFormatInstance;
    118            }
    119
    120            public String toString() {
    121                    final StringBuilder sb = new StringBuilder();
    122                    for (HeadRule rule : this.values()) {
    123                            sb.append(rule);
    124                            sb.append('\n');
    125                    }
    126                    return sb.toString();
    127            }
    128    }