FilteredRangeFacetHandler.java

package com.browseengine.bobo.facets.impl;

import java.io.IOException;
import java.util.Arrays;
import java.util.HashSet;
import java.util.List;
import java.util.Properties;

import com.browseengine.bobo.api.BoboSegmentReader;
import com.browseengine.bobo.api.BrowseSelection;
import com.browseengine.bobo.api.FacetSpec;
import com.browseengine.bobo.facets.FacetCountCollector;
import com.browseengine.bobo.facets.FacetCountCollectorSource;
import com.browseengine.bobo.facets.FacetHandler;
import com.browseengine.bobo.facets.FacetHandler.FacetDataNone;
import com.browseengine.bobo.facets.data.FacetDataCache;
import com.browseengine.bobo.facets.filter.RandomAccessFilter;
import com.browseengine.bobo.sort.DocComparatorSource;

public class FilteredRangeFacetHandler extends FacetHandler<FacetDataNone> {
  private final List<String> _predefinedRanges;
  private final String _inner;
  private RangeFacetHandler _innerHandler;

  public FilteredRangeFacetHandler(String name, String underlyingHandler,
      List<String> predefinedRanges) {
    super(name, new HashSet<String>(Arrays.asList(underlyingHandler)));
    _predefinedRanges = predefinedRanges;
    _inner = underlyingHandler;
    _innerHandler = null;
  }

  @Override
  public RandomAccessFilter buildRandomAccessFilter(String value, Properties selectionProperty)
      throws IOException {
    return _innerHandler.buildRandomAccessFilter(value, selectionProperty);
  }

  @Override
  public RandomAccessFilter buildRandomAccessAndFilter(String[] vals, Properties prop)
      throws IOException {
    return _innerHandler.buildRandomAccessAndFilter(vals, prop);
  }

  @Override
  public RandomAccessFilter buildRandomAccessOrFilter(String[] vals, Properties prop, boolean isNot)
      throws IOException {
    return _innerHandler.buildRandomAccessOrFilter(vals, prop, isNot);
  }

  @Override
  public FacetCountCollectorSource getFacetCountCollectorSource(final BrowseSelection sel,
      final FacetSpec fspec) {
    return new FacetCountCollectorSource() {

      @Override
      public FacetCountCollector getFacetCountCollector(BoboSegmentReader reader, int docBase) {
        FacetDataCache<?> dataCache = _innerHandler.getFacetData(reader);
        return new RangeFacetCountCollector(_name, dataCache, docBase, fspec, _predefinedRanges);
      }
    };

  }

  @Override
  public String[] getFieldValues(BoboSegmentReader reader, int id) {
    return _innerHandler.getFieldValues(reader, id);
  }

  @Override
  public Object[] getRawFieldValues(BoboSegmentReader reader, int id) {
    return _innerHandler.getRawFieldValues(reader, id);
  }

  @Override
  public DocComparatorSource getDocComparatorSource() {
    return _innerHandler.getDocComparatorSource();
  }

  @Override
  public FacetDataNone load(BoboSegmentReader reader) throws IOException {
    FacetHandler<?> handler = reader.getFacetHandler(_inner);
    if (handler instanceof RangeFacetHandler) {
      _innerHandler = (RangeFacetHandler) handler;
      return FacetDataNone.instance;
    } else {
      throw new IOException("inner handler is not instance of " + RangeFacetHandler.class);
    }
  }
}