<dependency>
  <groupId>com.itfsw</groupId>
  <artifactId>QueryBuilder</artifactId>
  <version>1.0.4</version>
</dependency>

public class Test {
    @Autowired
    private JdbcTemplate jdbcTemplate;
    @Autowired
    private MongoTemplate mongoTemplate;
    public void test() throws IOException {
        String json = "{\"condition\":\"OR\",\"rules\":[{\"id\":\"name\",\"field\":\"username\",\"type\":\"string\",\"input\":\"text\",\"operator\":\"equal\",\"value\":\"Mistic\"}],\"not\":false,\"valid\":true}";
        // ----------------------------------------- SQL -----------------------------------------
        // get SqlBuilder
        SqlQueryBuilderFactory sqlQueryBuilderFactory = new SqlQueryBuilderFactory();
        SqlBuilder sqlBuilder = sqlQueryBuilderFactory.builder();
        // build query
        SqlQueryResult sqlQueryResult = sqlBuilder.build(json);
        // execute
        jdbcTemplate.query(new StringBuffer("SELECT * FROM `user` WHERE ").append(sqlQueryResult.getQuery()).toString(), sqlQueryResult.getParams().toArray(), rs -> {
            System.out.println(rs.getString("username"));
        });
        // ----------------------------------------- Mongodb -----------------------------------------
        // get MongodbBuilder
        MongodbQueryBuilderFactory mongodbQueryBuilderFactory = new MongodbQueryBuilderFactory();
        MongodbBuilder mongodbBuilder = mongodbQueryBuilderFactory.builder();
        // build query
        MongodbQueryResult mongodbQueryResult = mongodbBuilder.build(json);
        // execute
        DBCursor cursor = mongoTemplate.getCollection("user").find(mongodbQueryResult.getQuery());
        while (cursor.hasNext()){
            System.out.println(cursor.next().get("username"));
        }
    }
}