Added method to honor backwards compatibility.

json-path/src/main/java/com/jayway/jsonpath/Criteria.java

@@ -388,9 +388,34 @@ public class Criteria implements Predicate {
      */
     @Deprecated
     public static Criteria parse(String criteria) {
-        //TODO: fix
+        if(criteria == null){
-        return null;
+            throw new InvalidPathException("Criteria can not be null");
         }
+        String[] split = criteria.trim().split(" ");
+        if(split.length == 3){
+            return create(split[0], split[1], split[2]);
+        } else if(split.length == 1){
+            return create(split[0], "EXISTS", "true");
+        } else {
+            throw new InvalidPathException("Could not parse criteria");
+        }
+    }
+
+    /**
+     * Creates a new criteria
+     * @param left path to evaluate in criteria
+     * @param operator operator
+     * @param right expected value
+     * @return a new Criteria
+     */
+    @Deprecated
+    public static Criteria create(String left, String operator, String right) {
+        Criteria criteria = new Criteria(ValueNode.toValueNode(left));
+        criteria.criteriaType = RelationalOperator.fromString(operator);
+        criteria.right = ValueNode.toValueNode(right);
+        return criteria;
+    }
+
 
     private static String prefixPath(String key){
         if (!key.startsWith("$") && !key.startsWith("@")) {

json-path/src/test/java/com/jayway/jsonpath/FilterTest.java

@@ -469,4 +469,14 @@ public class FilterTest extends BaseTest {
         Object json = Configuration.defaultConfiguration().jsonProvider().parse("{\"firstname\":\"Bob\",\"surname\":\"Smith\",\"age\":30}");
         assertThat(Filter.parse("[?((@.firstname == 'Bob' || @.firstname == 'Jane') && @.surname == 'Smith')]").apply(createPredicateContext(json))).isTrue();
     }
+
+    @Test
+    public void criteria_can_be_parsed() {
+
+        Criteria criteria = Criteria.parse("@.foo == 'baar'");
+        assertThat(criteria.toString()).isEqualTo("@['foo'] == 'baar'");
+
+        criteria = Criteria.parse("@.foo");
+        assertThat(criteria.toString()).isEqualTo("@['foo']");
+    }
 }