基于Java学生疫情信息管理系统，主要是对学生体温登记，来访学生登记，发布公告，修改学生戒管理员信息等 操作.zip

package com.dream.utils; import com.alibaba.druid.pool.DruidDataSource; import java.io.IOException; import java.lang.reflect.Field; import java.sql.*; import java.util.ArrayList; import java.util.Properties; public class DBUtil { private static Properties voConfigProperties; private static DruidDataSource dataSource; static { Properties p = new Properties(); try { p.load(DBUtil.class.getClassLoader().getResourceAsStream("DBConfig.properties")); } catch (IOException e) { e.printStackTrace(); } String driverName = p.getProperty("driverName"); String url = p.getProperty("url"); String username = p.getProperty("username"); String password = p.getProperty("password"); //创建德鲁伊数据库连接池 dataSource = new DruidDataSource(); //设置参数 dataSource.setDriverClassName(driverName);//加载驱动 dataSource.setUrl(url); dataSource.setUsername(username); dataSource.setPassword(password); dataSource.setMaxActive(1000); voConfigProperties = new Properties(); try { voConfigProperties.load(DBUtil.class.getClassLoader().getResourceAsStream("VOConfig.properties")); } catch (IOException e) { e.printStackTrace(); } } //开启事务 public static void startTransaction(){ try { //获取连接对象 Connection connection = getConnection(); //开启事务 connection.setAutoCommit(false); //存入ThreadLocal中 local.set(connection); } catch (SQLException e) { e.printStackTrace(); } } //提交事务 public static void commit(){ Connection connection = local.get(); if(connection != null){ try { connection.commit(); connection.close(); local.set(null); } catch (SQLException e) { e.printStackTrace(); } } } //回滚事务 public static void rollback(){ Connection connection = local.get(); if(connection != null){ try { connection.rollback(); connection.close(); local.set(null); } catch (SQLException e) { e.printStackTrace(); } } } private static ThreadLocal<Connection> local = new ThreadLocal<>(); //获取连接对象 public static Connection getConnection() throws SQLException{ Connection connection = local.get(); if(connection == null){ connection = dataSource.getConnection(); //设置事务的隔离级别 connection.setTransactionIsolation(Connection.TRANSACTION_REPEATABLE_READ); local.set(connection); } return connection; } public static void close(Connection connection, Statement statement, ResultSet resultSet){ if (resultSet != null){ try { resultSet.close(); } catch (SQLException e) { e.printStackTrace(); } } if (statement != null){ try { statement.close(); } catch (SQLException e) { e.printStackTrace(); } } if (connection != null){ try { if(connection.getAutoCommit()){//没有开启事务才能关闭 try { System.out.println("关闭链接"); connection.close(); local.set(null); } catch (SQLException e) { e.printStackTrace(); } } } catch (SQLException e) { e.printStackTrace(); } } } /** * 查询 * @param c 实体类的字节码文件对象 * @param sql SQL指令 * @param param SQL参数 * @param <T> 实体类的类型 * @return 实体类对象的集合 */ public static<T> ArrayList<T> commonQuery(Class<T> c,String sql, Object... param){ Connection connection = null; PreparedStatement statement = null; ResultSet resultSet = null; try { connection = getConnection(); statement = connection.prepareStatement(sql); //设置SQL参数 for (int i = 0; i < param.length; i++) { statement.setObject(i+1,param[i]); } //发送SQL指令 resultSet = statement.executeQuery(); //获取到表单对象 ResultSetMetaData metaData = resultSet.getMetaData(); //获取字段名的个数 int columnCount = metaData.getColumnCount(); ArrayList<T> list = new ArrayList<>(); //遍历数据 while(resultSet.next()){ //利用反射创建对象 T t = c.newInstance(); for (int i = 1; i <= columnCount; i++) { //获取字段名 String columnName = metaData.getColumnName(i); //获取该字段名对应的数据 Object obj = resultSet.getObject(columnName); //将数据存入对象中 try {//先找子类，再找父类 Field field = getField(c, columnName); setField(field,t,obj); } catch (NoSuchFieldException e) {//找配置文件中的属性名 System.out.println(columnName); String voConfigFeildName = voConfigProperties.getProperty(columnName); try { Field field = getField(c, voConfigFeildName); setField(field,t,obj); } catch (NoSuchFieldException e1) { e1.printStackTrace(); } } } list.add(t); } return list; } catch (SQLException e) { e.printStackTrace(); } catch (IllegalAccessException e) { e.printStackTrace(); } catch (InstantiationException e) { e.printStackTrace(); } return null; } //设置属性 public static<T> void setField(Field field,T t,Object obj){ field.setAccessible(true); try { field.set(t,obj); } catch (IllegalAccessException e) { e.printStackTrace(); } } //获取到属性对象 public static<T> Field getField(Class<T> c,String fieldName) throws NoSuchFieldException { try { Field field = c.getDeclaredField(fieldName); return field; } catch (NoSuchFieldException e) { //找父类中的属性 for( Class<? super T> superclass = c.getSuperclass();superclass!=null;superclass=superclass.getSuperclass()){ try { Field field = superclass.getDeclaredField(fieldName); return field; } catch (NoSuchFieldException e1){ } } } throw new NoSuchFieldException(); } /** * 添加、修改、删除 * @param sql SQL指令 * @param param 参数 */ public static void commonUpdate(String sql,Object... param){ Connection connection = null; PreparedStatement statement = null; ResultSet resultSet = null; try { connection = getConnection(); statement = connection.prepareStatement(sql); for (int i = 0; i < param.length; i++) { statement.setObject(i