Update AdminDaoImpl.java

ticketing-master/src/com/cn/dao/impl/AdminDaoImpl.java

@@ -1,70 +1,50 @@
-package com.cn.dao.impl;
+package com.cn.dao.impl; // 数据访问对象实现包
 
-import java.sql.Connection;
+import java.sql.*; // 导入SQL相关类
-import java.sql.PreparedStatement;
+import java.util.*; // 导入集合相关类
-import java.sql.ResultSet;
-import java.sql.SQLException;
-import java.sql.Timestamp;
-import java.util.ArrayList;
-import java.util.List;
 
-import com.cn.dao.AdminDao;
+import com.cn.dao.AdminDao; // 导入AdminDao接口
-import com.cn.domain.Admin;
+import com.cn.domain.Admin; // 导入Admin实体类
-import com.cn.util.JDBCUtil;
+import com.cn.util.JDBCUtil; // 导入JDBC工具类
 
 /**
- * @className AdminDaoImpl
+ * 实现AdminDao接口，提供管理员数据访问操作。
- * @description
- * @author lxs
- * @date 2019年9月1日
  */
 public class AdminDaoImpl implements AdminDao {
-	private Connection conn = null;
+    private Connection conn = null; // 数据库连接
-	private PreparedStatement pstmt = null;
+    private PreparedStatement pstmt = null; // 预编译语句
-	private ResultSet rs = null;
+    private ResultSet rs = null; // 结果集
 
     @Override
-	public int add(Admin admin) throws SQLException {
+    public int add(Admin admin) throws SQLException { // 添加管理员
         String sql = "insert into admins (username,password,creattime,flag,isuse,logintime) VALUES (?,?,?,?,?,?)";
-
+        conn = JDBCUtil.getConnection(); // 获取连接
-		conn = JDBCUtil.getConnection();
+        pstmt = conn.prepareStatement(sql); // 准备SQL语句
-		pstmt = conn.prepareStatement(sql);
+        pstmt.setObject(1, admin.getUserName()); // 设置参数
-		pstmt.setObject(1, admin.getUserName());
         pstmt.setObject(2, admin.getPassword());
         pstmt.setObject(3, admin.getCreatTime());
         pstmt.setObject(4, admin.getFlag());
         pstmt.setObject(5, admin.getIsUse());
         pstmt.setObject(6, admin.getLoginTime());
-		// 执行添加语句
+        int status = pstmt.executeUpdate(); // 执行插入
-		int status = pstmt.executeUpdate();
+        closeResources(); // 关闭资源
-		// 关流
-		pstmt.close();
-		conn.close();
-		
         return status;
     }
 
     @Override
-	public int delete(int adminId) throws SQLException {
+    public int delete(int adminId) throws SQLException { // 删除管理员
         String sql = "delete from admins where adminid=?";
-		
         conn = JDBCUtil.getConnection();
         pstmt = conn.prepareStatement(sql);
         pstmt.setObject(1, adminId);
-		// 执行删除语句
         int status = pstmt.executeUpdate();
-		
+        closeResources();
-		pstmt.close();
-		conn.close();
-		
         return status;
     }
 
-	
     @Override
-	public int update(Admin admin) throws SQLException {
+    public int update(Admin admin) throws SQLException { // 更新管理员信息
         String sql = "update admins set username=?,password=?,flag=?,isuse=?,logintime=? where adminid=?";
-		
         conn = JDBCUtil.getConnection();
         pstmt = conn.prepareStatement(sql);
         pstmt.setObject(1, admin.getUserName());
@@ -73,90 +53,89 @@ public class AdminDaoImpl implements AdminDao {
         pstmt.setObject(4, admin.getIsUse());
         pstmt.setObject(5, admin.getLoginTime());
         pstmt.setObject(6, admin.getAdminId());
-		
         int status = pstmt.executeUpdate();
-		
+        closeResources();
-		pstmt.close();
-		conn.close();
-		
         return status;
     }
 
     @Override
-	public Admin getById(int adminId) throws SQLException {
+    public Admin getById(int adminId) throws SQLException { // 根据ID获取管理员
         String sql = "select * from admins where adminid=?";
         conn = JDBCUtil.getConnection();
         pstmt = conn.prepareStatement(sql);
         pstmt.setObject(1, adminId);
         rs = pstmt.executeQuery();
         Admin admin = null;
-		while (rs.next()) {
+        if (rs.next()) {
-			String userName = rs.getString("userName");
+            admin = resultSetToAdmin(rs); // 将结果集转换为Admin对象
-			String password = rs.getString("password");
-			Timestamp creatTime = rs.getTimestamp("creatTime");
-			int flag = rs.getInt("flag");
-			int isUse = rs.getInt("isUse");
-			Timestamp loginTime = rs.getTimestamp("loginTime");
-			admin = new Admin(adminId, userName, password, creatTime, flag, isUse, loginTime);
         }
-		
+        closeResources();
-		rs.close();
-		pstmt.close();
-		conn.close();
-		
         return admin;
     }
 
     @Override
-	public List<Admin> getAll() throws SQLException{
+    public List<Admin> getAll() throws SQLException { // 获取所有管理员
         String sql = "select * from admins";
-		
         conn = JDBCUtil.getConnection();
         pstmt = conn.prepareStatement(sql);
         rs = pstmt.executeQuery();
-		
+        List<Admin> admins = new ArrayList<>();
-		List<Admin> admins = new ArrayList<Admin>();
         while (rs.next()) {
-			int adminId = rs.getInt("adminId");
+            admins.add(resultSetToAdmin(rs)); // 将结果集转换为Admin对象并添加到列表
-			String userName = rs.getString("userName");
-			String password = rs.getString("password");
-			Timestamp creatTime = rs.getTimestamp("creatTime");
-			int flag = rs.getInt("flag");
-			int isUse = rs.getInt("isUse");
-			Timestamp loginTime = rs.getTimestamp("loginTime");
-			Admin admin = new Admin(adminId, userName, password, creatTime, flag, isUse, loginTime);
-			admins.add(admin);
         }
-		
+        closeResources();
-		rs.close();
-		pstmt.close();
-		conn.close();
-		
         return admins;
     }
 
     @Override
-	public Admin getByName(String userName) throws SQLException {
+    public Admin getByName(String userName) throws SQLException { // 根据用户名获取管理员
         String sql = "select * from admins where username=?";
         conn = JDBCUtil.getConnection();
         pstmt = conn.prepareStatement(sql);
         pstmt.setObject(1, userName);
         rs = pstmt.executeQuery();
         Admin admin = null;
-		while (rs.next()) {
+        if (rs.next()) {
+            admin = resultSetToAdmin(rs); // 将结果集转换为Admin对象
+        }
+        closeResources();
+        return admin;
+    }
+
+    // 将结果集转换为Admin对象的方法
+    private Admin resultSetToAdmin(ResultSet rs) throws SQLException {
         int adminId = rs.getInt("adminId");
+        String userName = rs.getString("userName");
         String password = rs.getString("password");
         Timestamp creatTime = rs.getTimestamp("creatTime");
         int flag = rs.getInt("flag");
         int isUse = rs.getInt("isUse");
         Timestamp loginTime = rs.getTimestamp("loginTime");
-			admin = new Admin(adminId, userName, password, creatTime, flag, isUse, loginTime);
+        return new Admin(adminId, userName, password, creatTime, flag, isUse, loginTime);
     }
 
+    // 关闭数据库资源的方法
+    private void closeResources() {
+        if (rs != null) {
+            try {
                 rs.close();
+            } catch (SQLException e) {
+                e.printStackTrace();
+            }
+        }
+        if (pstmt != null) {
+            try {
                 pstmt.close();
+            } catch (SQLException e) {
+                e.printStackTrace();
+            }
+        }
+        if (conn != null) {
+            try {
                 conn.close();
-		
+            } catch (SQLException e) {
-		return admin;
+                e.printStackTrace();
+            }
+        }
     }
 }