[ch05] 5.12, Used DBConnectionPool.

Signed-off-by: Dongho Sim <dhsim86@gmail.com>
dhsim86 · Mar 25, 2017 · 1c860a3 · 1c860a3
1 parent 0f6202d
commit 1c860a3
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Showing 4 changed files with 91 additions and 16 deletions.
diff --git a/src/main/java/ContextLoaderListener.java b/src/main/java/ContextLoaderListener.java
@@ -1,11 +1,10 @@
+import Lesson05.DBConnectionPool;
 import Lesson05.MemberDao;
 
 import javax.servlet.ServletContext;
 import javax.servlet.ServletContextEvent;
 import javax.servlet.ServletContextListener;
 import javax.servlet.annotation.WebListener;
-import java.sql.Connection;
-import java.sql.DriverManager;
 
 /**
  * Created by Dongho on 2017. 3. 25..
@@ -14,23 +13,23 @@
 @WebListener
 public class ContextLoaderListener implements ServletContextListener {
 
-    private Connection conn;
+    private DBConnectionPool dbConnectionPool;
 
     @Override
     public void contextInitialized(ServletContextEvent event) {
 
         try {
             ServletContext sc = event.getServletContext();
 
-            Class.forName(sc.getInitParameter("driver"));
-            conn = DriverManager.getConnection(
+            dbConnectionPool = new DBConnectionPool(
+                sc.getInitParameter("driver"),
                 sc.getInitParameter("url"),
                 sc.getInitParameter("username"),
                 sc.getInitParameter("password")
             );
 
             MemberDao memberDao = new MemberDao();
-            memberDao.setConnection(conn);
+            memberDao.setDbConnectionPool(dbConnectionPool);
 
             sc.setAttribute("memberDao", memberDao);
         }
@@ -41,10 +40,7 @@ public void contextInitialized(ServletContextEvent event) {
 
     @Override
     public void contextDestroyed(ServletContextEvent event) {
-        try {
-            conn.close();
-        } catch (Exception e) {
 
-        }
+        dbConnectionPool.closeAll();
     }
 }
diff --git a/src/main/java/Lesson05/DBConnectionPool.java b/src/main/java/Lesson05/DBConnectionPool.java
@@ -0,0 +1,55 @@
+package Lesson05;
+
+import java.sql.Connection;
+import java.sql.DriverManager;
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * Created by Dongho on 2017. 3. 25..
+ */
+public class DBConnectionPool {
+
+    private String url;
+    private String username;
+    private String password;
+
+    List<Connection> connectionList = new ArrayList<>();
+
+    public DBConnectionPool(String driver, String url, String username, String password)
+        throws Exception {
+
+        this.url = url;
+        this.username = username;
+        this.password = password;
+
+        Class.forName(driver);
+    }
+
+    public Connection getConnection() throws Exception {
+
+        if (connectionList.size() > 0) {
+
+            Connection conn = connectionList.get(0);
+
+            if (conn.isValid(10)) {
+                return conn;
+            }
+        }
+
+        return DriverManager.getConnection(url, username, password);
+    }
+
+    public void returnConnection(Connection conn) throws Exception {
+
+        connectionList.add(conn);
+    }
+
+    public void closeAll() {
+
+        for (Connection conn : connectionList) {
+
+            try { conn.close(); } catch (Exception e) {}
+        }
+    }
+}
diff --git a/src/main/java/Lesson05/LoginServlet.java b/src/main/java/Lesson05/LoginServlet.java
@@ -36,10 +36,9 @@ protected void doPost(
 
             ServletContext sc = this.getServletContext();
 
-            MemberDao memberdao = new MemberDao();
-            memberdao.setConnection((Connection)sc.getAttribute("conn"));
+            MemberDao memberDao = (MemberDao)sc.getAttribute("memberDao");
 
-            Member member = memberdao.exist(
+            Member member = memberDao.exist(
                 request.getParameter("email"),
                 request.getParameter("password")
             );

diff --git a/src/main/java/Lesson05/MemberDao.java b/src/main/java/Lesson05/MemberDao.java
@@ -9,18 +9,22 @@
  */
 public class MemberDao {
 
-    Connection connection;
+    private DBConnectionPool dbConnectionPool;
 
-    public void setConnection(Connection connection) {
-        this.connection = connection;
+    public void setDbConnectionPool(DBConnectionPool dbConnectionPool) {
+        this.dbConnectionPool = dbConnectionPool;
     }
 
     public List<Member> selectList() throws Exception {
 
+        Connection connection = null;
         Statement stmt = null;
         ResultSet rs = null;
 
         try {
+
+            connection = dbConnectionPool.getConnection();
+
             stmt = connection.createStatement();
             rs = stmt.executeQuery(
                 "select mno, mname, email, cre_date" +
@@ -47,14 +51,20 @@ public List<Member> selectList() throws Exception {
         finally {
             try { if (rs != null) rs.close(); } catch (Exception e) {}
             try { if (stmt != null) stmt.close(); } catch (Exception e) {}
+
+            if (connection != null) dbConnectionPool.returnConnection(connection);
         }
     }
 
     public int insert(Member member) throws Exception {
 
+        Connection connection = null;
         PreparedStatement stmt = null;
 
         try {
+
+            connection = dbConnectionPool.getConnection();
+
             stmt = connection.prepareStatement(
                 "insert into members(email, pwd, mname, cre_date, mod_date)" +
                 " values(?, ?, ?, now(), now())"
@@ -71,15 +81,19 @@ public int insert(Member member) throws Exception {
         }
         finally {
             try { if (stmt != null) stmt.close(); } catch (Exception e) {}
+            if (connection != null) dbConnectionPool.returnConnection(connection);
         }
     }
 
     public int delete(int no) throws Exception {
 
+        Connection connection = null;
         PreparedStatement stmt = null;
 
         try {
 
+            connection = dbConnectionPool.getConnection();
+
             stmt = connection.prepareStatement(
                 "delete from members" +
                 " where mno = ?"
@@ -94,16 +108,19 @@ public int delete(int no) throws Exception {
         }
         finally {
             try { if (stmt != null) stmt.close(); } catch (Exception e) {}
+            if (connection != null) dbConnectionPool.returnConnection(connection);
         }
     }
 
     public Member selectOne(int no) throws Exception {
 
+        Connection connection = null;
         PreparedStatement stmt = null;
         ResultSet rs = null;
 
         try {
 
+            connection = dbConnectionPool.getConnection();
             stmt = connection.prepareStatement(
                 "select mno, mname, email, cre_date" +
                 " from members" +
@@ -130,15 +147,19 @@ public Member selectOne(int no) throws Exception {
         finally {
             try { if (rs != null) rs.close(); } catch (Exception e) {}
             try { if (stmt != null) stmt.close(); } catch (Exception e) {}
+            if (connection != null) dbConnectionPool.returnConnection(connection);
         }
     }
 
     public int update(Member member) throws Exception {
 
+        Connection connection = null;
         PreparedStatement stmt = null;
 
         try {
 
+            connection = dbConnectionPool.getConnection();
+
             stmt = connection.prepareStatement(
                 "update members set email = ?, mname = ?, mod_date = now()" +
                 " where mno = ?"
@@ -155,16 +176,19 @@ public int update(Member member) throws Exception {
         }
         finally {
             try { if (stmt != null) stmt.close(); } catch (Exception e) {}
+            if (connection != null) dbConnectionPool.returnConnection(connection);
         }
     }
 
     public Member exist(String email, String password) throws Exception {
 
+        Connection connection = null;
         PreparedStatement stmt = null;
         ResultSet rs = null;
 
         try {
 
+            connection = dbConnectionPool.getConnection();
             stmt = connection.prepareStatement(
                 " select mno, mname, email, cre_date" +
                 " from members" +
@@ -195,6 +219,7 @@ public Member exist(String email, String password) throws Exception {
         finally {
             try { if (rs != null) rs.close(); } catch (Exception e) {}
             try { if (stmt != null) stmt.close(); } catch (Exception e) {}
+            if (connection != null) dbConnectionPool.returnConnection(connection);
         }
     }
 }