AVRO-1711: Java: Fix JsonDecoder#skipChildren skipping extra tokens.

Contributed by Zoltan Farkas and Thiruvalluvan M. G.
kaaproject · May 8, 2016 · 7e10bab · 7e10bab
1 parent 4fe9b45
commit 7e10bab
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Showing 3 changed files with 25 additions and 4 deletions.
diff --git a/CHANGES.txt b/CHANGES.txt
@@ -57,6 +57,9 @@ Trunk (not yet released)
 
     AVRO-1814: Generated java code fails on variables with a TLD name like 'org' (nielsbasjes)
 
+    AVRO-1711: Java: Fix JsonParser#skipChildren to implement its defined contract.
+    (Zoltan Farkas and Thiruvalluvan M. G. via blue)
+
 Avro 1.8.0 (22 January 2016)
 
   INCOMPATIBLE CHANGES

diff --git a/lang/java/avro/src/main/java/org/apache/avro/io/JsonDecoder.java b/lang/java/avro/src/main/java/org/apache/avro/io/JsonDecoder.java
@@ -579,9 +579,10 @@ public JsonToken nextToken() throws IOException {
 
       @Override
       public JsonParser skipChildren() throws IOException {
-        int level = 0;
-        do {
-          switch(elements.get(pos++).token) {
+        JsonToken tkn = elements.get(pos).token;
+        int level = (tkn == JsonToken.START_ARRAY || tkn == JsonToken.END_ARRAY) ? 1 : 0;
+        while (level > 0) {
+          switch(elements.get(++pos).token) {
           case START_ARRAY:
           case START_OBJECT:
             level++;
@@ -591,7 +592,7 @@ public JsonParser skipChildren() throws IOException {
             level--;
             break;
           }
-        } while (level > 0);
+        }
         return this;
       }
 

diff --git a/lang/java/avro/src/test/java/org/apache/avro/io/TestJsonDecoder.java b/lang/java/avro/src/test/java/org/apache/avro/io/TestJsonDecoder.java
@@ -60,4 +60,21 @@ private void checkNumeric(String type, Object value) throws Exception {
     }
   }
 
+  // Ensure that even if the order of fields in JSON is different from the order in schema,
+  // it works.
+  @Test public void testReorderFields() throws Exception {
+    String w =
+      "{\"type\":\"record\",\"name\":\"R\",\"fields\":"
+      +"[{\"type\":\"long\",\"name\":\"l\"},"
+      +"{\"type\":{\"type\":\"array\",\"items\":\"int\"},\"name\":\"a\"}"
+      +"]}";
+    Schema ws = Schema.parse(w);
+    DecoderFactory df = DecoderFactory.get();
+    String data = "{\"a\":[1,2],\"l\":100}{\"l\": 200, \"a\":[1,2]}";
+    JsonDecoder in = df.jsonDecoder(ws, data);
+    Assert.assertEquals(100, in.readLong());
+    in.skipArray();
+    Assert.assertEquals(200, in.readLong());
+    in.skipArray();
+  }
 }