Jackson serialization for clustering classes

main/src/com/google/refine/clustering/ClusteredEntry.java

@@ -0,0 +1,27 @@
+package com.google.refine.clustering;
+
+import java.io.Serializable;
+import java.util.Comparator;
+
+import com.fasterxml.jackson.annotation.JsonProperty;
+
+public class ClusteredEntry {
+    @JsonProperty("v")
+    protected final Serializable value;
+    @JsonProperty("c")
+    protected final int count;
+    
+    public ClusteredEntry(
+            Serializable value,
+            int count) {
+        this.value = value;
+        this.count = count;
+    }
+    
+    public static Comparator<ClusteredEntry> comparator = new Comparator<ClusteredEntry>() {
+        @Override
+        public int compare(ClusteredEntry o1, ClusteredEntry o2) {
+            return o2.count - o1.count;
+        }
+    };
+}

main/src/com/google/refine/clustering/ClustererConfig.java

@@ -2,6 +2,8 @@ package com.google.refine.clustering;
 
 import org.json.JSONObject;
 
+import com.fasterxml.jackson.annotation.JsonProperty;
+
 import com.google.refine.Jsonizable;
 import com.google.refine.model.Project;
 
@@ -22,6 +24,7 @@ public abstract class ClustererConfig implements Jsonizable {
         columnName = o.getString("column");
     }
     
+    @JsonProperty("column")
     public String getColumnName() {
         return columnName;
     }
@@ -32,4 +35,10 @@ public abstract class ClustererConfig implements Jsonizable {
      * @return
      */
     public abstract Clusterer apply(Project project);
+    
+    /**
+     * Type string used in Json serialization
+     */
+    @JsonProperty("type")
+    public abstract String getType();
 }

main/src/com/google/refine/clustering/binning/BinningClusterer.java

@@ -43,6 +43,7 @@ import java.util.Map;
 import java.util.Map.Entry;
 import java.util.Properties;
 import java.util.TreeMap;
+import java.util.stream.Collectors;
 
 import org.json.JSONException;
 import org.json.JSONObject;
@@ -50,10 +51,17 @@ import org.json.JSONWriter;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
+import com.fasterxml.jackson.annotation.JsonIgnore;
+import com.fasterxml.jackson.annotation.JsonInclude;
+import com.fasterxml.jackson.annotation.JsonInclude.Include;
+import com.fasterxml.jackson.annotation.JsonProperty;
+import com.fasterxml.jackson.annotation.JsonValue;
+
 import com.google.refine.Jsonizable;
 import com.google.refine.browsing.Engine;
 import com.google.refine.browsing.FilteredRows;
 import com.google.refine.browsing.RowVisitor;
+import com.google.refine.clustering.ClusteredEntry;
 import com.google.refine.clustering.Clusterer;
 import com.google.refine.clustering.ClustererConfig;
 import com.google.refine.model.Cell;
@@ -64,6 +72,7 @@ public class BinningClusterer extends Clusterer {
     
     public static class BinningClustererConfig extends ClustererConfig {
        
+        @JsonProperty("function")
         private String _keyerName;
         private Keyer _keyer;
         private BinningParameters _parameters;
@@ -80,10 +89,13 @@ public class BinningClusterer extends Clusterer {
             }
         }
         
+        @JsonIgnore
         public Keyer getKeyer() {
             return _keyer;
         }
         
+        @JsonProperty("params")
+        @JsonInclude(Include.NON_NULL)
         public BinningParameters getParameters() {
             return _parameters;
         }
@@ -109,9 +121,16 @@ public class BinningClusterer extends Clusterer {
             return clusterer;
         }
 
+        @Override
+        public String getType() {
+            return "binning";
+        }
+        
     }
     
     public static class BinningParameters implements Jsonizable {
+        @JsonProperty("ngram-size")
+        @JsonInclude(Include.NON_DEFAULT)
         public int ngramSize;
 
         @Override
@@ -276,4 +295,22 @@ public class BinningClusterer extends Clusterer {
         }
         writer.endArray();
     }
+    
+    protected static Map<String,Object> entryToMap(Entry<String,Integer> entry) {
+        Map<String,Object> map = new HashMap<>();
+        map.put("v", entry.getKey());
+        map.put("c", entry.getValue());
+        return map;
+    }
+    
+    @JsonValue
+    public List<List<ClusteredEntry>> getJsonRepresentation() {
+        EntriesComparator c = new EntriesComparator();
+        return _clusters.stream()
+                .map(m -> m.entrySet().stream()
+                        .sorted(c)
+                        .map(e -> new ClusteredEntry(e.getKey(), e.getValue()))
+                        .collect(Collectors.toList()))
+                .collect(Collectors.toList());
+    }
 }

main/src/com/google/refine/clustering/knn/kNNClusterer.java

@@ -44,6 +44,7 @@ import java.util.Map;
 import java.util.Map.Entry;
 import java.util.Properties;
 import java.util.Set;
+import java.util.stream.Collectors;
 
 import org.json.JSONException;
 import org.json.JSONObject;
@@ -51,10 +52,15 @@ import org.json.JSONWriter;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
+import com.fasterxml.jackson.annotation.JsonIgnore;
+import com.fasterxml.jackson.annotation.JsonProperty;
+import com.fasterxml.jackson.annotation.JsonValue;
+
 import com.google.refine.Jsonizable;
 import com.google.refine.browsing.Engine;
 import com.google.refine.browsing.FilteredRows;
 import com.google.refine.browsing.RowVisitor;
+import com.google.refine.clustering.ClusteredEntry;
 import com.google.refine.clustering.Clusterer;
 import com.google.refine.clustering.ClustererConfig;
 import com.google.refine.model.Cell;
@@ -76,6 +82,7 @@ import edu.mit.simile.vicino.distances.PPMDistance;
 public class kNNClusterer extends Clusterer {
     
     public static class kNNClustererConfig extends ClustererConfig {
+        @JsonProperty("function")
         private String _distanceStr;
         private Distance _distance;
         private kNNClustererConfigParameters _parameters;
@@ -105,10 +112,12 @@ public class kNNClusterer extends Clusterer {
             }
         }
         
+        @JsonIgnore
         public Distance getDistance() {
             return _distance;
         }
         
+        @JsonProperty("params")
         public kNNClustererConfigParameters getParameters() {
             return _parameters;
         }
@@ -120,12 +129,19 @@ public class kNNClusterer extends Clusterer {
             return clusterer;
         }
 
+        @Override
+        public String getType() {
+            return "knn";
+        }
+        
     }
     
     public static class kNNClustererConfigParameters implements Jsonizable {
         public static final double defaultRadius = 1.0d;
         public static final int defaultBlockingNgramSize = 6;
+        @JsonProperty("radius")
         public double radius = defaultRadius;
+        @JsonProperty("blocking-ngram-size")
         public int blockingNgramSize = defaultBlockingNgramSize;
         
         @Override
@@ -302,6 +318,21 @@ public class kNNClusterer extends Clusterer {
         writer.endArray();
     }
     
+    protected List<ClusteredEntry> getClusteredEntries(Set<Serializable> s) {
+        return s.stream()
+                .map(e -> new ClusteredEntry(e, _counts.get(e)))
+                .sorted(ClusteredEntry.comparator)
+                .collect(Collectors.toList());
+    }
+    
+    @JsonValue
+    public List<List<ClusteredEntry>> getJsonRepresentation() {
+        return _clusters.stream()
+                        .filter(m -> m.size() > 1)
+                        .map(m -> getClusteredEntries(m))
+                .collect(Collectors.toList());
+    }
+    
     private void count(Serializable s) {
         if (_counts.containsKey(s)) {
             _counts.put(s, _counts.get(s) + 1);