Get a comment back to keep the intention of Exception handling

src/main/java/org/embulk/parser/json/JsonParserPlugin.java

@@ -185,6 +185,14 @@ public void run(TaskSource taskSource, Schema schema, FileInput input, PageOutpu
  throw new JsonRecordValidateException("A Json record doesn't have given 'JSON pointer to root'.");
  }
  } catch (JsonParseException e) {
+ /*
+ * When JsonParseException is thrown, it would be an error that
+ * the given JSON pointer doesn't match with the JSON object.
+ * We would return NULL when the pointer doesn't match, not throw Exception.
+ *
+ * NOTE: We may change the behavior.
+ * See: https://github.com/embulk/embulk/pull/1103#discussion_r255807991
+ */
  throw new JsonRecordValidateException("A Json record doesn't have given 'JSON pointer to root'.");
  }
  }
@@ -284,6 +292,14 @@ private void setValueWithCustomSchema(
  .build(valueAsJsonString)
  .readJsonValue();
  } catch (final IOException ex) {
+ /*
+ * When JsonParseException is thrown, it would be an error that
+ * the given JSON pointer doesn't match with the JSON object.
+ * We would return NULL when the pointer doesn't match, not throw Exception.
+ *
+ * NOTE: We may change the behavior.
+ * See: https://github.com/embulk/embulk/pull/1103#discussion_r255807991
+ */
  throw new JsonParseException("Failed to parse JSON: " + valueAsJsonString, ex);
  }
  } else {