package com.hgd.study.JDBC;import java.net.CookieHandler;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;public class DB {Connection conn = null;PreparedStatement pst;ResultSet rSet;public static void main(String[] args) {DB db = new DB();List<Student> students = null;try {db.initConn();//students = db.select();//students = db.selectByStu(20);
Student stu = new Student();stu.setAgestart(20);stu.setAgeend(22);students = db.selectByCondition(stu);for (int i = 0; i < students.size(); i++) {System.out.print(students.get(i).getId() + "\t");System.out.print(students.get(i).getName() + "\t");System.out.print(students.get(i).getAge());System.out.println();}// Student stu = new Student(123, "李四", 23);// db.save(stu);// Student stu=new Student();// stu.setId(10003);// stu.setAge(23);// db.update(stu);// db.delete(123);/** 事物： 1.原子性：每一个事物都是一个单独的操作 2.一致性：事物中的所有操作，只要成功全部成功，一旦失败全部失败* 3.隔离性：事物中的操作之间没不会产生影响他们都是一个独立的操作 4.持久性：事物一旦成功将被永久写入数据库*/// conn.setAutoCommit(false);// 设置自动事物为false// conn.setSavepoint();// 设置事物的回滚点// conn.rollback();//事物回滚// conn.commit();//事物提交// db.setAutoCommit(false);// db.setSavepoint();// Student stu = new Student();// stu.setId(10003);// stu.setAge(0);// db.update(stu);// if (stu.getAge() <= 0) {// db.rollback();// System.out.println("取消了操作");// } else {// db.commit();// }
} catch (Exception e) {// TODO 自动生成的 catch 块
            e.printStackTrace();} finally {try {db.close();} catch (Exception e) {// TODO 自动生成的 catch 块
                e.printStackTrace();}}}// 初始化public void init() {// 不同的数据库有不同的驱动String driverName = "oracle.jdbc.driver.OracleDriver";String url = "jdbc:oracle:thin:@192.168.1.150:1521:XE";String user = "hr";String password = "123456";try {// 加载驱动
            Class.forName(driverName);// 设置 配置数据// 1.url(数据看服务器的ip地址 数据库服务端口号 数据库实例)// 2.user// 3.passwordconn = DriverManager.getConnection(url, user, password);// 开始连接数据库System.out.println("数据库连接成功..");} catch (ClassNotFoundException e) {// TODO 自动生成的 catch 块
            e.printStackTrace();} catch (SQLException e) {// TODO 自动生成的 catch 块
            e.printStackTrace();}}public void initConn() throws Exception {if (conn == null || conn.isClosed()) {this.init();}}public void close() throws Exception {if (conn != null && !conn.isClosed()) {conn.close();conn = null;}}public void setAutoCommit(boolean fals) throws Exception {if (conn != null && !conn.isClosed()) {conn.setAutoCommit(fals);}}public void setSavepoint() throws Exception {if (conn != null && !conn.isClosed()) {conn.setSavepoint();}}public void rollback() throws Exception {if (conn != null && !conn.isClosed()) {conn.rollback();}}public void commit() throws Exception {if (conn != null && !conn.isClosed()) {conn.commit();}}// 简单查询public List<Student> select() throws SQLException {List<Student> list = new ArrayList<Student>();// *查询// 创建sql语句String sqlString = "select * from student";// 编译sql语句// 执行查询pst = conn.prepareStatement(sqlString);rSet = pst.executeQuery();// 遍历结果Student student = null;while (rSet.next()) {// System.out.print(rSet.getInt(1) + "\t");// System.out.print(rSet.getString(2) + "\t");// System.out.print(rSet.getInt(3) + "\t");// System.out.print("\n");student = new Student();student.setId(rSet.getInt(1));student.setName(rSet.getString(2));student.setAge(rSet.getInt(3));list.add(student);}return list;}// 条件查询public List<Student> selectByStu(int age) throws SQLException {List<Student> students = new ArrayList<Student>();String sql = "select * from student where sage=? ";pst = conn.prepareStatement(sql);// 设置条件(相对于条件查询)pst.setInt(1, age);rSet = pst.executeQuery();Student student = null;while (rSet.next()) {student = new Student();student.setId(rSet.getInt(1));student.setName(rSet.getString(2));student.setAge(rSet.getInt(3));students.add(student);}return students;}// 多个条件值查询public List<Student> selectByCondition(Student e) throws SQLException {List<Student> students = new ArrayList<Student>();String sql = "select * from student where sage>? and sage<? ";pst = conn.prepareStatement(sql);pst.setInt(1, e.getAgestart());pst.setInt(2, e.getAgeend());rSet = pst.executeQuery();Student student = null;while (rSet.next()) {student = new Student();student.setId(rSet.getInt(1));student.setName(rSet.getString(2));student.setAge(rSet.getInt(3));students.add(student);}return students;}// 添加数据public void save(Student student) throws SQLException {String sql = "insert into student values (?,?,?,null,null,null,null,null)";pst = conn.prepareStatement(sql);pst.setInt(1, student.getId());pst.setString(2, student.getName());pst.setInt(3, student.getAge());pst.executeUpdate();System.out.println("添加成功");}// 更新数据public void update(Student student) throws SQLException {String sql = "update student set sage=? where sid=?";pst = conn.prepareStatement(sql);pst.setInt(1, student.getAge());pst.setInt(2, student.getId());pst.executeUpdate();System.out.println("更新成功");}// 删除数据public void delete(Integer id) throws SQLException {String sql = "delete student where sid=?";pst = conn.prepareStatement(sql);pst.setInt(1, id);pst.executeUpdate();System.out.println("删除成功");}// 分页public List<Student> findByPage(int start, int end) throws SQLException {List<Student> students = new ArrayList<Student>();String sql = "select s_.* from(select  s.*,rownum rn from (select * from student order by sid) s where rownum<=?) s_  where rn>?";pst = conn.prepareStatement(sql);pst.setInt(1, end);pst.setInt(2, start);rSet = pst.executeQuery();Student student = null;while (rSet.next()) {student = new Student();student.setId(rSet.getInt(1));student.setName(rSet.getString(2));student.setAge(rSet.getInt(3));students.add(student);}return students;}}