spring-toby-3 [Spring] 3. 템플릿 (3.6 - refactoring)

chapter2/src/main/java/com/example/chapter2/dao/UserDao.java

@@ -30,7 +30,7 @@ public void add(User user) throws SQLException {
     public User get(String id) throws SQLException {
         try (
                 Connection c = dataSource.getConnection();
-                PreparedStatement ps = c.prepareStatement("SELECT * FROM USERS WHERE id = ?")
+                PreparedStatement ps = makeStatement(c);
         ) {
             ps.setString(1, id);
             ResultSet rs = ps.executeQuery();
@@ -51,6 +51,10 @@ public User get(String id) throws SQLException {
         }
     }
 
+    private PreparedStatement makeStatement(Connection c) throws SQLException {
+        return c.prepareStatement("SELECT * FROM USERS WHERE id = ?");
+    }
+
     public int getCount() throws SQLException {
         try (
                 Connection c = dataSource.getConnection();

chapter3/src/main/java/com/example/template/part2/context/JdbcContext.java

@@ -1,14 +1,19 @@
 package com.example.template.part2.context;
 
 import com.example.template.part1.strategy.StatementStrategy;
+import lombok.NoArgsConstructor;
+import lombok.Setter;
 
 import javax.sql.DataSource;
 import java.sql.Connection;
 import java.sql.PreparedStatement;
 import java.sql.SQLException;
 
+@Setter
+@NoArgsConstructor
 public class JdbcContext {
-    private final DataSource dataSource;
+
+    private DataSource dataSource;
 
     public JdbcContext(DataSource dataSource) {
         this.dataSource = dataSource;
@@ -22,4 +27,13 @@ public void workWithStatementStrategy(StatementStrategy strategy) throws SQLExce
             s.executeUpdate();
         }
     }
+
+    public void executeSql(final String query) throws SQLException {
+        workWithStatementStrategy(new StatementStrategy() {
+            @Override
+            public PreparedStatement makePreparedStatement(Connection c) throws SQLException {
+                return c.prepareStatement(query);
+            }
+        });
+    }
 }

chapter3/src/main/java/com/example/template/part2/dao/UserDaoDataSourceDI.java

@@ -3,17 +3,21 @@
 import com.example.template.part1.User;
 import com.example.template.part1.strategy.StatementStrategy;
 import com.example.template.part2.context.JdbcContext;
+import org.springframework.context.annotation.Configuration;
 
 import javax.sql.DataSource;
 import java.sql.Connection;
 import java.sql.PreparedStatement;
 import java.sql.SQLException;
 
+@Configuration
 public class UserDaoDataSourceDI {
+
     private final JdbcContext context;
 
     public UserDaoDataSourceDI(DataSource dataSource) {
-        this.context = new JdbcContext(dataSource);
+        this.context = new JdbcContext();
+        context.setDataSource(dataSource);
     }
 
     public void add(User user) throws SQLException {

chapter3/src/main/java/com/example/template/part2/dao/UserDaoJdbcContextDI.java

@@ -5,6 +5,7 @@
 import com.example.template.part1.strategy.StatementStrategy;
 import com.example.template.part1.strategy.TruncateStatement;
 import com.example.template.part2.context.JdbcContext;
+import org.springframework.context.annotation.Configuration;
 import org.springframework.dao.EmptyResultDataAccessException;
 
 import javax.sql.DataSource;
@@ -42,13 +43,6 @@ public PreparedStatement makePreparedStatement(Connection c) throws SQLException
     }
 
     public void truncateTable() throws SQLException {
-        this.context.workWithStatementStrategy(
-                new StatementStrategy() {
-                    @Override
-                    public PreparedStatement makePreparedStatement(Connection c) throws SQLException {
-                        return c.prepareStatement("TRUNCATE TABLE USERS");
-                    }
-                }
-        );
+        this.context.executeSql("TRUNCATE TABLE USERS");
     }
 }

chapter3/src/main/java/com/example/template/part3/UserDaoCallback.java

@@ -1,13 +1,10 @@
 package com.example.template.part3;
 
 import com.example.template.part1.User;
-import com.example.template.part1.strategy.StatementStrategy;
 import org.springframework.jdbc.core.JdbcTemplate;
 import org.springframework.jdbc.core.RowMapper;
 
 import javax.sql.DataSource;
-import java.sql.Connection;
-import java.sql.PreparedStatement;
 import java.sql.ResultSet;
 import java.sql.SQLException;
 import java.util.List;