Migrate GREL functions and controls to Jackson

main/src/com/google/refine/expr/ExpressionUtils.java

@@ -41,9 +41,8 @@ import java.util.List;
 import java.util.Properties;
 import java.util.Set;
 
-import org.json.JSONArray;
+import com.fasterxml.jackson.databind.node.ArrayNode;
-import org.json.JSONObject;
+import com.fasterxml.jackson.databind.node.ObjectNode;
-
 import com.google.refine.model.Cell;
 import com.google.refine.model.Project;
 import com.google.refine.model.Row;
@@ -150,10 +149,10 @@ public class ExpressionUtils {
     }
 
     static public Serializable wrapStorable(Object v) {
-        if (v instanceof JSONArray) {
+        if (v instanceof ArrayNode) {
-            return ((JSONArray) v).toString();
+            return ((ArrayNode) v).toString();
-        } else if (v instanceof JSONObject) {
+        } else if (v instanceof ObjectNode) {
-            return ((JSONObject) v).toString();
+            return ((ObjectNode) v).toString();
         } else {
             return isStorable(v) ?
                 (Serializable) v :

main/src/com/google/refine/expr/functions/Get.java

@@ -36,13 +36,12 @@ package com.google.refine.expr.functions;
 import java.util.List;
 import java.util.Properties;
 
-import org.json.JSONArray;
+import com.fasterxml.jackson.databind.node.ArrayNode;
-import org.json.JSONException;
+import com.fasterxml.jackson.databind.node.ObjectNode;
-import org.json.JSONObject;
-
 import com.google.refine.expr.ExpressionUtils;
 import com.google.refine.expr.HasFields;
 import com.google.refine.expr.HasFieldsList;
+import com.google.refine.expr.util.JsonValueConverter;
 import com.google.refine.grel.Function;
 
 public class Get implements Function {
@@ -57,26 +56,22 @@ public class Get implements Function {
             if (v != null && from != null) {
                 if (v instanceof HasFields && from instanceof String) {
                     return ((HasFields) v).getField((String) from, bindings);
-                } else if (v instanceof JSONObject && from instanceof String) {
+                } else if (v instanceof ObjectNode && from instanceof String) {
-                    try {
+                    return JsonValueConverter.convert(((ObjectNode) v).get((String) from));
-                        return ((JSONObject) v).get((String) from);
-                    } catch (JSONException e) {
-                        // ignore; will return null
-                    }
                 } else {
                     if (from instanceof Number && (to == null || to instanceof Number)) {
                         if (v.getClass().isArray() || 
                             v instanceof List<?> || 
                             v instanceof HasFieldsList || 
-                            v instanceof JSONArray) {
+                            v instanceof ArrayNode) {
                             
                             int length = 0;
                             if (v.getClass().isArray()) { 
                                 length = ((Object[]) v).length;
                             } else if (v instanceof HasFieldsList) {
                                 length = ((HasFieldsList) v).length();
-                            } else if (v instanceof JSONArray) {
+                            } else if (v instanceof ArrayNode) {
-                                length = ((JSONArray) v).length();
+                                length = ((ArrayNode) v).size();
                             } else {
                                 length = ExpressionUtils.toObjectList(v).size();
                             }
@@ -92,12 +87,8 @@ public class Get implements Function {
                                     return ((Object[]) v)[start];
                                 } else if (v instanceof HasFieldsList) {
                                     return ((HasFieldsList) v).get(start);
-                                } else if (v instanceof JSONArray) {
+                                } else if (v instanceof ArrayNode) {
-                                    try {
+                                    return JsonValueConverter.convert(((ArrayNode) v).get(start));
-                                        return ((JSONArray) v).get(start);
-                                    } catch (JSONException e) {
-                                        // ignore; will return null
-                                    }
                                 } else {
                                     return ExpressionUtils.toObjectList(v).get(start);
                                 }
@@ -118,18 +109,13 @@ public class Get implements Function {
                                         return a2;
                                     } else if (v instanceof HasFieldsList) {
                                         return ((HasFieldsList) v).getSubList(start, end);
-                                    } else if (v instanceof JSONArray) {
+                                    } else if (v instanceof ArrayNode) {
-                                        JSONArray a = (JSONArray) v;
+                                        ArrayNode a = (ArrayNode) v;
                                         Object[] a2 = new Object[end - start];
                                         
                                         for (int i = 0; i < a2.length; i++) {
-                                            try {
+                                            a2[i] = JsonValueConverter.convert(a.get(start + i)); 
-                                                a2[i] = a.get(start + i);
-                                            } catch (JSONException e) {
-                                                // ignore
                                         }
-                                        }
-                                        
                                         return a2;
                                     } else {
                                         return ExpressionUtils.toObjectList(v).subList(start, end);

main/src/com/google/refine/expr/functions/HasField.java

@@ -35,9 +35,7 @@ package com.google.refine.expr.functions;
 
 import java.util.Properties;
 
-import org.json.JSONException;
+import com.fasterxml.jackson.databind.node.ObjectNode;
-import org.json.JSONObject;
-
 import com.google.refine.expr.HasFields;
 import com.google.refine.grel.Function;
 
@@ -53,12 +51,8 @@ public class HasField implements Function {
                 String name = (String) f;
                 if (v instanceof HasFields) {
                     return ((HasFields) v).getField(name, bindings) != null;
-                } else if (v instanceof JSONObject) {
+                } else if (v instanceof ObjectNode) {
-                    try {
+                    return ((ObjectNode) v).has(name);
-                        return ((JSONObject) v).get(name) != null;
-                    } catch (JSONException e) {
-                        // ignore; will return false
-                    }
                 }
             }
         }

main/src/com/google/refine/expr/functions/Jsonize.java

@@ -33,15 +33,11 @@ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 package com.google.refine.expr.functions;
 
-import java.util.Collection;
+import java.io.IOException;
-import java.util.Map;
 import java.util.Properties;
 
-import org.json.JSONArray;
-import org.json.JSONException;
-import org.json.JSONObject;
-
 import com.google.refine.grel.Function;
+import com.google.refine.util.ParsingUtilities;
 
 public class Jsonize implements Function {
 
@@ -49,27 +45,8 @@ public class Jsonize implements Function {
     public Object call(Properties bindings, Object[] args) {
         if (args.length >= 1) {
             try {
-                Object o1 = args[0];
+                return ParsingUtilities.mapper.writeValueAsString(args[0]);
-                if (o1 == null) {
+            } catch (IOException e) {
-                    return "null";
-                } else if (o1 instanceof Number) {
-                    return JSONObject.numberToString((Number) o1);
-                } else if (o1 instanceof Boolean) {
-                    return o1.toString();
-                } else if (o1 instanceof JSONObject) {
-                    return ((JSONObject) o1).toString();
-                } else if (o1 instanceof JSONArray) {
-                    return ((JSONArray) o1).toString();
-                } else if (o1 instanceof Map) {
-                    return new JSONObject((Map<?,?>) o1).toString();
-                } else if (o1 instanceof Collection) {
-                    return new JSONArray((Collection<?>) o1).toString();
-                } else if (o1.getClass().isArray()) {
-                    return new JSONArray(o1).toString();
-                } else {
-                    return JSONObject.quote(o1.toString());
-                }
-            } catch (JSONException e) {
                 throw new RuntimeException(e);
             }
         }

main/src/com/google/refine/expr/functions/Length.java

@@ -36,8 +36,7 @@ package com.google.refine.expr.functions;
 import java.util.Collection;
 import java.util.Properties;
 
-import org.json.JSONArray;
+import com.fasterxml.jackson.databind.node.ArrayNode;
-
 import com.google.refine.expr.EvalError;
 import com.google.refine.expr.HasFieldsList;
 import com.google.refine.grel.ControlFunctionRegistry;
@@ -58,8 +57,8 @@ public class Length implements Function {
                     return ((Collection<?>) v).size();
                 } else if (v instanceof HasFieldsList) {
                     return ((HasFieldsList) v).length();
-                } else if (v instanceof JSONArray) {
+                } else if (v instanceof ArrayNode) {
-                    return ((JSONArray) v).length();
+                    return ((ArrayNode) v).size();
                 } else {
                     String s = (v instanceof String ? (String) v : v.toString());
                     return s.length();

main/src/com/google/refine/expr/functions/Slice.java

@@ -36,9 +36,7 @@ package com.google.refine.expr.functions;
 import java.util.List;
 import java.util.Properties;
 
-import org.json.JSONArray;
+import com.fasterxml.jackson.databind.node.ArrayNode;
-import org.json.JSONException;
-
 import com.google.refine.expr.ExpressionUtils;
 import com.google.refine.expr.HasFieldsList;
 import com.google.refine.grel.Function;
@@ -53,14 +51,14 @@ public class Slice implements Function {
             Object to = (args.length == 3) ? args[2] : null;
             
             if (v != null && from != null && from instanceof Number && (to == null || to instanceof Number)) {
-                if (v.getClass().isArray() || v instanceof List<?> || v instanceof HasFieldsList || v instanceof JSONArray) {
+                if (v.getClass().isArray() || v instanceof List<?> || v instanceof HasFieldsList || v instanceof ArrayNode) {
                     int length = 0;
                     if (v.getClass().isArray()) { 
                         length = ((Object[]) v).length;
                     } else if (v instanceof HasFieldsList) {
                         length = ((HasFieldsList) v).length();
-                    } else if (v instanceof JSONArray) {
+                    } else if (v instanceof ArrayNode) {
-                        length = ((JSONArray) v).length();
+                        length = ((ArrayNode) v).size();
                     } else {
                         length = ExpressionUtils.toObjectList(v).size();
                     }
@@ -86,16 +84,12 @@ public class Slice implements Function {
                         return a2;
                     } else if (v instanceof HasFieldsList) {
                         return ((HasFieldsList) v).getSubList(start, end);
-                    } else if (v instanceof JSONArray) {
+                    } else if (v instanceof ArrayNode) {
-                        JSONArray a = (JSONArray) v;
+                        ArrayNode a = (ArrayNode) v;
                         Object[] a2 = new Object[end - start];
                         
                         for (int i = 0; i < a2.length; i++) {
-                            try {
                             a2[i] = a.get(start + i);
-                            } catch (JSONException e) {
-                                // ignore
-                            }
                         }
                         
                         return a2;

main/src/com/google/refine/expr/functions/arrays/Join.java

@@ -36,9 +36,9 @@ package com.google.refine.expr.functions.arrays;
 import java.util.List;
 import java.util.Properties;
 
-import org.json.JSONArray;
 import org.json.JSONException;
 
+import com.fasterxml.jackson.databind.node.ArrayNode;
 import com.google.refine.expr.EvalError;
 import com.google.refine.expr.ExpressionUtils;
 import com.google.refine.grel.ControlFunctionRegistry;
@@ -55,7 +55,7 @@ public class Join implements Function {
             if (v != null && s != null && s instanceof String) {
                 String separator = (String) s;
                 
-                if (v.getClass().isArray() || v instanceof List<?> || v instanceof JSONArray) {
+                if (v.getClass().isArray() || v instanceof List<?> || v instanceof ArrayNode) {
                     StringBuffer sb = new StringBuffer();
                     if (v.getClass().isArray()) {
                         for (Object o : (Object[]) v) {
@@ -66,9 +66,9 @@ public class Join implements Function {
                                 sb.append(o.toString());
                             }
                         }
-                    } else if (v instanceof JSONArray) {
+                    } else if (v instanceof ArrayNode) {
-                        JSONArray a = (JSONArray) v;
+                        ArrayNode a = (ArrayNode) v;
-                        int l = a.length();
+                        int l = a.size();
                         
                         for (int i = 0; i < l; i++) {
                             if (sb.length() > 0) {

main/src/com/google/refine/expr/functions/arrays/Reverse.java

@@ -36,9 +36,7 @@ package com.google.refine.expr.functions.arrays;
 import java.util.List;
 import java.util.Properties;
 
-import org.json.JSONArray;
+import com.fasterxml.jackson.databind.node.ArrayNode;
-import org.json.JSONException;
-
 import com.google.refine.expr.EvalError;
 import com.google.refine.expr.ExpressionUtils;
 import com.google.refine.grel.ControlFunctionRegistry;
@@ -53,13 +51,8 @@ public class Reverse implements Function {
             Object v = args[0];
             
             if (v != null) {
-                if (v instanceof JSONArray) {
+                if (v instanceof ArrayNode) {
-                    try {
+                    v = JSONUtilities.toArray((ArrayNode) v);
-                        v = JSONUtilities.toArray((JSONArray) v);
-                    } catch (JSONException e) {
-                        return new EvalError(ControlFunctionRegistry.getFunctionName(this) +
-                                " fails to process a JSON array: " + e.getMessage());
-                    }
                 }
                 
                 if (v.getClass().isArray() || v instanceof List<?>) {

main/src/com/google/refine/expr/functions/arrays/Sort.java

@@ -38,9 +38,7 @@ import java.util.Collections;
 import java.util.List;
 import java.util.Properties;
 
-import org.json.JSONArray;
+import com.fasterxml.jackson.databind.node.ArrayNode;
-import org.json.JSONException;
-
 import com.google.refine.expr.EvalError;
 import com.google.refine.grel.ControlFunctionRegistry;
 import com.google.refine.grel.Function;
@@ -62,17 +60,12 @@ public class Sort implements Function {
                     Arrays.sort(r, 0, r.length);
                     
                     return r;
-                } else if (v instanceof JSONArray) {
+                } else if (v instanceof ArrayNode) {
-                    try {
+                    Object[] r = JSONUtilities.toArray((ArrayNode) v);
-                        Object[] r = JSONUtilities.toArray((JSONArray) v);
                     
                     Arrays.sort(r, 0, r.length);
                     
                     return r;
-                    } catch (JSONException e) {
-                        return new EvalError(ControlFunctionRegistry.getFunctionName(this) +
-                                " fails to process a JSON array: " + e.getMessage());
-                    }
                 } else if (v instanceof List<?>) {
                     List<? extends Comparable<Object>> a = (List<? extends Comparable<Object>>) v;
                     Collections.sort(a);

main/src/com/google/refine/expr/functions/arrays/Uniques.java

@@ -38,9 +38,7 @@ import java.util.List;
 import java.util.Properties;
 import java.util.Set;
 
-import org.json.JSONArray;
+import com.fasterxml.jackson.databind.node.ArrayNode;
-import org.json.JSONException;
-
 import com.google.refine.expr.EvalError;
 import com.google.refine.expr.ExpressionUtils;
 import com.google.refine.grel.ControlFunctionRegistry;
@@ -55,13 +53,8 @@ public class Uniques implements Function {
             Object v = args[0];
             
             if (v != null) {
-                if (v instanceof JSONArray) {
+                if (v instanceof ArrayNode) {
-                    try {
+                    v = JSONUtilities.toArray((ArrayNode) v);
-                        v = JSONUtilities.toArray((JSONArray) v);
-                    } catch (JSONException e) {
-                        return new EvalError(ControlFunctionRegistry.getFunctionName(this) +
-                                " fails to process a JSON array: " + e.getMessage());
-                    }
                 }
                 
                 if (v.getClass().isArray() || v instanceof List<?>) {

main/src/com/google/refine/expr/functions/strings/ParseJson.java

@@ -33,14 +33,13 @@ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 package com.google.refine.expr.functions.strings;
 
+import java.io.IOException;
 import java.util.Properties;
 
-import org.json.JSONException;
-import org.json.JSONTokener;
-
 import com.google.refine.expr.EvalError;
 import com.google.refine.grel.ControlFunctionRegistry;
 import com.google.refine.grel.Function;
+import com.google.refine.util.ParsingUtilities;
 
 public class ParseJson implements Function {
 
@@ -50,8 +49,8 @@ public class ParseJson implements Function {
             Object o1 = args[0];
             if (o1 != null) {
                 try {
-                    return new JSONTokener(o1.toString()).nextValue();
+                    return ParsingUtilities.mapper.readTree(o1.toString());
-                } catch (JSONException e) {
+                } catch (IOException e) {
                     return new EvalError(ControlFunctionRegistry.getFunctionName(this) + " failed: " + e.getMessage());
                 }
             }

main/src/com/google/refine/expr/util/JsonValueConverter.java

@@ -0,0 +1,37 @@
+package com.google.refine.expr.util;
+
+import com.fasterxml.jackson.databind.JsonNode;
+
+/**
+ * Converts the a JSON value
+ * @author antonin
+ *
+ */
+public class JsonValueConverter {
+
+	public static Object convert(JsonNode value) {
+		if (value == null) {
+			return null;
+		}
+		if (value.isObject()) {
+			return value;
+		} else if (value.isArray()) {
+    		return value;
+    	} else if (value.isBigDecimal() || value.isDouble() || value.isFloat()) {
+    		return value.asDouble();
+    	} else if (value.isBigInteger()) {
+    		return value.asLong();
+    	} else if (value.isInt()) {
+    		return value.asInt();
+    	} else if (value.isBinary() || value.isTextual()) {
+    		return value.asText();
+    	} else if (value.isBoolean()) {
+    		return value.asBoolean();
+    	} else if (value.isNull()) {
+    		return null;
+    	} else {
+    		return null;
+    	}
+	}
+
+}

main/src/com/google/refine/grel/ast/FieldAccessorExpr.java

@@ -41,6 +41,7 @@ import com.google.common.collect.Lists;
 import com.google.refine.expr.Evaluable;
 import com.google.refine.expr.ExpressionUtils;
 import com.google.refine.expr.HasFields;
+import com.google.refine.expr.util.JsonValueConverter;
 
 /**
  * An abstract syntax tree node encapsulating a field accessor,
@@ -67,21 +68,7 @@ public class FieldAccessorExpr implements Evaluable {
             return ((HasFields) o).getField(_fieldName, bindings);
         } else if (o instanceof ObjectNode) {
         	JsonNode value = ((ObjectNode) o).get(_fieldName);
-        	if (value.isArray()) {
+        	return JsonValueConverter.convert(value);
-        		return Lists.newArrayList(value.elements());
-        	} else if (value.isBigDecimal() || value.isDouble() || value.isFloat()) {
-        		return value.asDouble();
-        	} else if (value.isBigInteger() || value.isInt()) {
-        		return value.asLong();
-        	} else if (value.isBinary() || value.isTextual()) {
-        		return value.asText();
-        	} else if (value.isBoolean()) {
-        		return value.asBoolean();
-        	} else if (value.isNull()) {
-        		return null;
-        	} else {
-        		return null;
-        	}
         } else {
             return null;
         }

main/src/com/google/refine/grel/controls/Filter.java

@@ -38,12 +38,11 @@ import java.util.Collection;
 import java.util.List;
 import java.util.Properties;
 
-import org.json.JSONArray;
+import com.fasterxml.jackson.databind.node.ArrayNode;
-import org.json.JSONException;
-
 import com.google.refine.expr.EvalError;
 import com.google.refine.expr.Evaluable;
 import com.google.refine.expr.ExpressionUtils;
+import com.google.refine.expr.util.JsonValueConverter;
 import com.google.refine.grel.Control;
 import com.google.refine.grel.ControlFunctionRegistry;
 import com.google.refine.grel.ast.VariableExpr;
@@ -65,7 +64,7 @@ public class Filter implements Control {
         Object o = args[0].evaluate(bindings);
         if (ExpressionUtils.isError(o)) {
             return o;
-        } else if (!ExpressionUtils.isArrayOrCollection(o) && !(o instanceof JSONArray)) {
+        } else if (!ExpressionUtils.isArrayOrCollection(o) && !(o instanceof ArrayNode)) {
             return new EvalError("First argument is not an array");
         }
         
@@ -91,14 +90,13 @@ public class Filter implements Control {
                         results.add(v);
                     }
                 }
-            } else if (o instanceof JSONArray) {
+            } else if (o instanceof ArrayNode) {
-                JSONArray a = (JSONArray) o;
+                ArrayNode a = (ArrayNode) o;
-                int l = a.length();
+                int l = a.size();
                 
                 results = new ArrayList<Object>(l);
                 for (int i = 0; i < l; i++) {
-                    try {
+                    Object v = JsonValueConverter.convert(a.get(i));
-                        Object v = a.get(i);
                     
                     if (v != null) {
                         bindings.put(name, v);
@@ -110,9 +108,6 @@ public class Filter implements Control {
                     if (r instanceof Boolean && ((Boolean) r).booleanValue()) {
                         results.add(v);
                     }
-                    } catch (JSONException e) {
-                        results.add(new EvalError(e.getMessage()));
-                    }
                 }
             } else {
                 Collection<Object> collection = ExpressionUtils.toObjectCollection(o);

main/src/com/google/refine/grel/controls/ForEach.java

@@ -38,12 +38,11 @@ import java.util.Collection;
 import java.util.List;
 import java.util.Properties;
 
-import org.json.JSONArray;
+import com.fasterxml.jackson.databind.node.ArrayNode;
-import org.json.JSONException;
-
 import com.google.refine.expr.EvalError;
 import com.google.refine.expr.Evaluable;
 import com.google.refine.expr.ExpressionUtils;
+import com.google.refine.expr.util.JsonValueConverter;
 import com.google.refine.grel.Control;
 import com.google.refine.grel.ControlFunctionRegistry;
 import com.google.refine.grel.ast.VariableExpr;
@@ -65,7 +64,7 @@ public class ForEach implements Control {
         Object o = args[0].evaluate(bindings);
         if (ExpressionUtils.isError(o)) {
             return o;
-        } else if (!ExpressionUtils.isArrayOrCollection(o) && !(o instanceof JSONArray)) {
+        } else if (!ExpressionUtils.isArrayOrCollection(o) && !(o instanceof ArrayNode)) {
             return new EvalError("First argument to forEach is not an array");
         }
         
@@ -90,14 +89,13 @@ public class ForEach implements Control {
                     
                     results.add(r);
                 }
-            } else if (o instanceof JSONArray) {
+            } else if (o instanceof ArrayNode) {
-                JSONArray a = (JSONArray) o;
+                ArrayNode a = (ArrayNode) o;
-                int l = a.length();
+                int l = a.size();
                 
                 results = new ArrayList<Object>(l);
                 for (int i = 0; i < l; i++) {
-                    try {
+                    Object v = JsonValueConverter.convert(a.get(i));
-                        Object v = a.get(i);
                     
                     if (v != null) {
                         bindings.put(name, v);
@@ -108,9 +106,6 @@ public class ForEach implements Control {
                     Object r = args[2].evaluate(bindings);
                     
                     results.add(r);
-                    } catch (JSONException e) {
-                        results.add(new EvalError(e.getMessage()));
-                    }
                 }
             } else {
                 Collection<Object> collection = ExpressionUtils.toObjectCollection(o);

main/src/com/google/refine/grel/controls/ForEachIndex.java

@@ -37,12 +37,11 @@ import java.util.ArrayList;
 import java.util.List;
 import java.util.Properties;
 
-import org.json.JSONArray;
+import com.fasterxml.jackson.databind.node.ArrayNode;
-import org.json.JSONException;
-
 import com.google.refine.expr.EvalError;
 import com.google.refine.expr.Evaluable;
 import com.google.refine.expr.ExpressionUtils;
+import com.google.refine.expr.util.JsonValueConverter;
 import com.google.refine.grel.Control;
 import com.google.refine.grel.ControlFunctionRegistry;
 import com.google.refine.grel.ast.VariableExpr;
@@ -67,7 +66,7 @@ public class ForEachIndex implements Control {
         Object o = args[0].evaluate(bindings);
         if (ExpressionUtils.isError(o)) {
             return o;
-        } else if (!ExpressionUtils.isArrayOrCollection(o) && !(o instanceof JSONArray)) {
+        } else if (!ExpressionUtils.isArrayOrCollection(o) && !(o instanceof ArrayNode)) {
             return new EvalError("First argument to forEach is not an array");
         }
         
@@ -94,14 +93,13 @@ public class ForEachIndex implements Control {
                     
                     results.add(r);
                 }
-            } else if (o instanceof JSONArray) {
+            } else if (o instanceof ArrayNode) {
-                JSONArray a = (JSONArray) o;
+                ArrayNode a = (ArrayNode) o;
-                int l = a.length();
+                int l = a.size();
                 
                 results = new ArrayList<Object>(l);
                 for (int i = 0; i < l; i++) {
-                    try {
+                    Object v = JsonValueConverter.convert(a.get(i));
-                        Object v = a.get(i);
                     
                     bindings.put(indexName, i);
                     bindings.put(elementName, v);
@@ -109,9 +107,6 @@ public class ForEachIndex implements Control {
                     Object r = args[3].evaluate(bindings);
                     
                     results.add(r);
-                    } catch (JSONException e) {
-                        results.add(new EvalError(e.getMessage()));
-                    }
                 }
             } else {
                 List<Object> list = ExpressionUtils.toObjectList(o);

main/src/com/google/refine/util/JSONUtilities.java

@@ -50,6 +50,7 @@ import com.fasterxml.jackson.databind.node.ArrayNode;
 import com.fasterxml.jackson.databind.node.JsonNodeType;
 import com.fasterxml.jackson.databind.node.ObjectNode;
 import com.google.common.collect.Lists;
+import com.google.refine.expr.util.JsonValueConverter;
 
 
 public class JSONUtilities {
@@ -477,4 +478,15 @@ public class JSONUtilities {
 	public static JSONObject objectNodeToJsonNode(ObjectNode fieldJsonObj) {
 		return new JSONObject(fieldJsonObj.toString());
 	}
+
+	public static Object[] toArray(ArrayNode v) {
+		if (v == null) {
+			return null;
+		}
+		Object[] result = new Object[v.size()];
+		for (int i = 0; i != v.size(); i++) {
+			result[i] = JsonValueConverter.convert(v.get(i));
+		}
+		return result;
+	}
 }

main/tests/server/src/com/google/refine/tests/expr/util/JsonValueConverterTests.java

@@ -0,0 +1,64 @@
+package com.google.refine.tests.expr.util;
+
+import static org.testng.Assert.assertEquals;
+
+import java.io.IOException;
+import java.util.Arrays;
+
+import org.testng.annotations.Test;
+
+import com.fasterxml.jackson.databind.node.ObjectNode;
+import com.google.refine.expr.util.JsonValueConverter;
+import com.google.refine.util.ParsingUtilities;
+
+public class JsonValueConverterTests {
+	
+	private void fieldEquals(String json, Object expectedValue) {
+		try {
+			ObjectNode n = (ObjectNode) ParsingUtilities.mapper.readTree(json);
+			assertEquals(expectedValue, JsonValueConverter.convert(n.get("foo")));
+		} catch (IOException e) {
+			e.printStackTrace();
+		}
+	}
+	
+	@Test
+	public void testConvertJsonObject() throws IOException {
+		fieldEquals("{\"foo\":{\"ob\":\"ject\"}}", ParsingUtilities.mapper.readTree("{\"ob\":\"ject\"}"));
+	}
+	
+	@Test
+	public void testConvertJsonArray() throws IOException {
+		fieldEquals("{\"foo\":[1,2]}", ParsingUtilities.mapper.readTree("[1,2]"));
+	}
+	
+	@Test
+	public void testConvertInt() {
+		fieldEquals("{\"foo\":3}", 3);
+	}
+	
+	@Test
+	public void testConvertFloat() {
+		fieldEquals("{\"foo\":3.14}", 3.14);
+	}
+	
+	@Test
+	public void testConvertBool() {
+		fieldEquals("{\"foo\":true}", true);
+	}
+
+	@Test
+	public void testConvertNull() {
+		fieldEquals("{\"foo\":null}", null);
+	}
+	
+	@Test
+	public void testConvertString() {
+		fieldEquals("{\"foo\":\"bar\"}", "bar");
+	}
+	
+	@Test
+	public void testConvertNoField() {
+		fieldEquals("{}", null);
+	}
+}