java实现oracle数据库基本操作

Posted 2020-06-25 SaraMorning

import java.sql.*;
import java.util.ArrayList;
import java.util.List;

//使用jdbc连接
public class TestOra {

    public static void main(String[] args) {
        // TODO Auto-generated method stub

        BaseDao basedao = new BaseDao();
        Connection conn = basedao.getConnection();
        basedao.add(conn);
        basedao.delete(conn);
        basedao.update(conn);
        basedao.query(conn);
        basedao.close();
    }
}

class BaseDao {
    private static String url = "jdbc:oracle:thin:@localhost:1521:orcl";
    private static String user = "c##scott";
    private static String password = "tiger";
    private Connection conn;
    private static Statement sm;
    private static ResultSet rs;
    private static String sql;

    // 连接数据库函数 
    public Connection getConnection() {
        try {
            // 初始化驱动包
            Class.forName("oracle.jdbc.OracleDriver");
            // 根据数据库连接字符，名称，密码给conn
            System.out.println("开始尝试连接数据库！");
            conn = DriverManager.getConnection(url, user, password);
        } catch (Exception e) {
            e.printStackTrace();
        }
        return conn;
    }

    // 查询函数
    public void query(Connection conn) {
        sql = "select * from EMP";
        try {
            sm = conn.createStatement();
            rs = sm.executeQuery(sql);
            while (rs.next()) {
                System.out.println("ID: " + rs.getString(1) + "\tNAME： "
                        + rs.getString(2) + "\tAGE： " + rs.getString(3));
            }
        } catch (Exception e) {
            e.printStackTrace();
        }

    }

    // 添加表数据
    public void add(Connection conn) {
        sql = "insert into EMP(ID,NAME,AGE)" + " values (‘0005‘,‘lucyyyy‘,‘14‘)";
        try {
            sm = conn.createStatement();
            sm.executeUpdate(sql);
            System.out.println("添加成功");
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    // 删除数据
    public void delete(Connection conn) {
        sql = "delete from EMP " + "where ID=‘2‘";
        try {
            sm = conn.createStatement();
            sm.executeUpdate(sql);
            System.out.println("删除成功");
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    // 修改数据
    public void update(Connection conn) {
        sql = "update EMP set ID=‘2‘ where NAME=‘lucy‘";
        try {
            sm = conn.createStatement();
            sm.executeUpdate(sql);
            System.out.println("更新成功");
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    public void close() {// 6.释放资源
        try { // 捕捉异常
            try {
                if (rs != null) { // 当ResultSet对象的实例rs不为空时
                    rs.close(); // 关闭ResultSet对象
                }
            } finally {
                try {
                    if (sm != null) { // 当Statement对象的实例stmt不为空时
                        sm.close(); // 关闭Statement对象
                    }
                } finally {
                    if (conn != null) { // 当Connection对象的实例conn不为空时
                        conn.close(); // 关闭Connection对象
                    }
                }
            }
        } catch (Exception e) {
            e.printStackTrace(System.err); // 输出异常信息
        }
    }
}