Refactor/#3 jdbc template 학습테스트 실패환경 구성

spring-jdbc-1/src/main/java/cholog/QueryingDAO.java

@@ -14,6 +14,7 @@ public QueryingDAO(JdbcTemplate jdbcTemplate) {
         this.jdbcTemplate = jdbcTemplate;
     }
 
+    /*
     private final RowMapper<Customer> actorRowMapper = (resultSet, rowNum) -> {
         Customer customer = new Customer(
                 resultSet.getLong("id"),
@@ -22,62 +23,49 @@ public QueryingDAO(JdbcTemplate jdbcTemplate) {
         );
         return customer;
     };
+    추후 rowMapper에 대해 학습해보고 이용해보기
+    */
 
     /**
      * public <T> T queryForObject(String sql, Class<T> requiredType)
      */
     public int count() {
-        String sql = "select count(*) from customers";
-        return jdbcTemplate.queryForObject(sql, Integer.class);
+        //TODO : customers 디비에 포함되어있는 row가 몇개인지 확인하는 기능 구현
+        return 0;
     }
 
     /**
      * public <T> T queryForObject(String sql, Class<T> requiredType, @Nullable Object... args)
      */
     public String getLastName(Long id) {
-        String sql = "select last_name from customers where id = ?";
-        return jdbcTemplate.queryForObject(sql, String.class, id);
+        //TODO : 주어진 Id에 해당하는 customers의 lastName을 반환
+        return null;
     }
 
     /**
      * public <T> T queryForObject(String sql, RowMapper<T> rowMapper, @Nullable Object... args)
      */
     public Customer findCustomerById(Long id) {
         String sql = "select id, first_name, last_name from customers where id = ?";
-        return jdbcTemplate.queryForObject(
-                sql,
-                (resultSet, rowNum) -> {
-                    Customer customer = new Customer(
-                            resultSet.getLong("id"),
-                            resultSet.getString("first_name"),
-                            resultSet.getString("last_name")
-                    );
-                    return customer;
-                }, id);
+        //TODO : 주어진 Id에 해당하는 customer를 객체로 반환
+        return null;
     }
 
     /**
      * public <T> List<T> query(String sql, RowMapper<T> rowMapper)
      */
     public List<Customer> findAllCustomers() {
         String sql = "select id, first_name, last_name from customers";
-        return jdbcTemplate.query(
-                sql,
-                (resultSet, rowNum) -> {
-                    Customer customer = new Customer(
-                            resultSet.getLong("id"),
-                            resultSet.getString("first_name"),
-                            resultSet.getString("last_name")
-                    );
-                    return customer;
-                });
+        //TODO : 저장된 모든 Customers를 list형태로 반환
+        return null;
     }
 
     /**
      * public <T> List<T> query(String sql, RowMapper<T> rowMapper, @Nullable Object... args)
      */
     public List<Customer> findCustomerByFirstName(String firstName) {
         String sql = "select id, first_name, last_name from customers where first_name = ?";
-        return jdbcTemplate.query(sql, actorRowMapper, firstName);
+        //TODO : firstName을 기준으로 customer를 list형태로 반환
+        return null;
     }
 }

spring-jdbc-1/src/main/java/cholog/UpdatingDAO.java

@@ -16,6 +16,7 @@ public UpdatingDAO(JdbcTemplate jdbcTemplate) {
         this.jdbcTemplate = jdbcTemplate;
     }
 
+    /*
     private final RowMapper<Customer> actorRowMapper = (resultSet, rowNum) -> {
         Customer customer = new Customer(
                 resultSet.getLong("id"),
@@ -24,37 +25,31 @@ public UpdatingDAO(JdbcTemplate jdbcTemplate) {
         );
         return customer;
     };
+    추후 rowMapper에 대해 학습해보고 이용해보기
+    */
 
     /**
      * public int update(String sql, @Nullable Object... args)
      */
     public void insert(Customer customer) {
-        String sql = "insert into customers (first_name, last_name) values (?, ?)";
-        jdbcTemplate.update(sql, customer.getFirstName(), customer.getLastName());
+        //todo: customer를 디비에 저장하기
     }
     /**
      * public int update(String sql, @Nullable Object... args)
      */
     public int delete(Long id) {
-        String sql = "delete from customers where id = ?";
-        return jdbcTemplate.update(sql, Long.valueOf(id));
+        //todo: id에 해당하는 customer를 지우고, 해당 쿼리에 영향받는 row 수반환하기
+        return 0;
     }
 
     /**
      * public int update(final PreparedStatementCreator psc, final KeyHolder generatedKeyHolder)
      */
     public Long insertWithKeyHolder(Customer customer) {
         String sql = "insert into customers (first_name, last_name) values (?, ?)";
-
         KeyHolder keyHolder = new GeneratedKeyHolder();
-        jdbcTemplate.update(connection -> {
-            PreparedStatement ps = connection.prepareStatement(
-                    "insert into customers (first_name, last_name) values (?, ?)",
-                    new String[]{"id"});
-            ps.setString(1, customer.getFirstName());
-            ps.setString(2, customer.getLastName());
-            return ps;
-        }, keyHolder);
+
+        //todo : keyHolder에 대해 학습하고, Customer를 저장후 저장된 Customer의 id를 반환하기
 
         Long id = keyHolder.getKey().longValue();
 

spring-jdbc-1/src/test/java/cholog/QueryingDaoTest.java

@@ -27,9 +27,10 @@ void setUp() {
         jdbcTemplate.execute("CREATE TABLE customers(" +
                 "id SERIAL, first_name VARCHAR(255), last_name VARCHAR(255))");
 
-        List<Object[]> splitUpNames = Arrays.asList("John Woo", "Jeff Dean", "Josh Bloch", "Josh Long").stream()
-                .map(name -> name.split(" "))
-                .collect(Collectors.toList());
+        List<Object[]> splitUpNames = Arrays.asList("John Woo", "Jeff Dean", "Josh Bloch", "Josh Long")
+            .stream()
+            .map(name -> name.split(" "))
+            .collect(Collectors.toList());
 
         jdbcTemplate.batchUpdate("INSERT INTO customers(first_name, last_name) VALUES (?,?)", splitUpNames);
     }
@@ -62,4 +63,11 @@ void findAllCustomers() {
 
         assertThat(customers).hasSize(4);
     }
+
+    @Test
+    void findCustomerByFirstName() {
+        List<Customer> customers = queryingDAO.findCustomerByFirstName("Josh");
+
+        assertThat(customers).hasSize(2);
+    }
 }