QueryBuilder

What is QueryBuilder ?

QueryBuilder is a system which generates queries automatically.

How to use QueryBuilder ?

   QueryBuilder queryBuilder = new QueryBuilder(); //create QueryBuilder instance

   String select = queryBuilder.select("users", "username", "password").build();
   //this method generates: SELECT username,password FROM users

   String select = queryBuilder.selectAll("users").build();
   //this method generates: SELECT * FROM users

   String query = queryBuilder.delete("users", "password", "username").build();
   //this method generates: DELETE password,username FROM users

   String query = queryBuilder.deleteAll("users").build();
   //this method generates: DELETE FROM users

  String query = queryBuilder.deleteAll("users").where("username = 'test'").build();
  //this method generates: DELETE FROM users WHERE username = 'test'
    
  String query = queryBuilder.insert("users", null, "user", 12).build();
  //this method generates: INSERT INTO users VALUES(null,'user',12)

  Map<String, Object> data = new HashMap<>();
  data.put("username", "test");
  data.put("age", 12);

  String query = queryBuilder.update("users", data).build();
  //this method generates: UPDATE users SET age = 12,username = 'test'

  List<Object> data = new ArrayList<>();
  data.add("test");
  data.add(12);
  data.add(UUID.fromString("4af94c03-9cbd-49f4-a77e-421a2c146160"));

  String query = queryBuilder.insert("test", null, data).build();
  //this method generates: INSERT INTO test VALUES(null,'test',12,'4af94c03-9cbd-49f4-a77e-421a2c146160')

  UUID uuid = UUID.fromString("4af94c03-9cbd-49f4-a77e-421a2c146160");
  String group = "Admin";

  Map<String, Object> data = new HashMap<>();
  data.put("username", "test");

   String query = queryBuilder.update("users", data)
         .where("uuid = '" + uuid + "' AND group = '" + group + "'")
         .build();
   //this method generates: UPDATE users SET username = 'test' WHERE uuid = '4af94c03-9cbd-49f4-a77e-421a2c146160' AND group = 'Admin'