[Demonstration 1]

[Buggy Method]
@Override
protected Range execute(Range range, String parameter) {
    return super.execute(range, parameter);
}

[Buggy Hunk]
protected Range execute(Range range, String parameter) {

[Patch]
public Range execute(Range range, String parameter) {

[Demonstration 2]

[Buggy Method]
private static Optional<Map<String, String>> toJson(String json) {
    Map<String, String> fields = null;
    JsonFactory factory = new JsonFactory();
    //factory.configure(JsonParser.Feature.ALLOW_UNQUOTED_FIELD_NAMES, true);
    ObjectMapper om = new ObjectMapper(factory);
    MapType type = om.getTypeFactory().constructMapType(HashMap.class, String.class, String.class);
    try {
        JsonParser jp = factory.createParser(json);
        fields = om.readValue(jp, type);
    } catch (IOException e) {
        e.printStackTrace();
    }
    return Optional.ofNullable(fields);
}

[Buggy Hunk]
e.printStackTrace();

[Patch]
Message.LOGGER.info("Can't read JSON (raw: "+json+"): "+e);

[Demonstration 3]

[Buggy Method]
private static Submission resultSetToSubmission(ResultSet rs) throws SQLException {
    try {
        ObjectMapper o = new ObjectMapper();
        String testPartsString = rs.getString("testSteps");
        List<TestStep> testSteps = null;
        if (!rs.wasNull()) {
            testSteps = o.readValue(testPartsString, new TypeReference<List<TestStep>>() {
            });
        }
        return new Submission(rs.getString("repoId"), rs.getString("tag"), rs.getString("compilationOutput"), rs.getLong("compilationTimeMs"), rs.getLong("harnessTimeMs"), rs.getLong("validatorTimeMs"), rs.getLong("waitTimeMs"), testSteps, rs.getString("errorMessage"), rs.getString("status"), rs.getTimestamp("dateScheduled"), rs.getString("interpretation"));
    } catch (IOException e) {
        throw new SQLException("Failed to deserialise json object", e);
    }
}

[Buggy Hunk]
throw new SQLException("Failed to deserialise json object",e);

[Patch]
throw new SQLException("Failed to deserialise json object "+e.getMessage(),e);