Java JDBC连接Oracle，java面试题，java初级笔试题

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1. 安装Oracle数据库，我这里使用的是Oracle 12c

 

2. 创建Java工程 connection-oracle

注意：使用的JavaSE-1.8

3. 在Oracle的安装目录里，将djdbc8.jar 拷贝到java工程

路径为：C:apporacleproduct .2.0dbhome_1jdbclib

4. 创建连接Oracle的java类

 

public class OracleJdbcTest {

	//数据库连接对象

	private static Connection conn = null;

	

	private static String driver = "oracle.jdbc.driver.OracleDriver"; //驱动

	

	private static String url = "jdbc:oracle:thin:@//127.0.0.1:1521/orcl"; //连接字符串

	

	private static String username = "system"; //用户名

	

	private static String password = "123456"; //密码

	

	

	// 获得连接对象

	private static synchronized Connection getConn(){

		if(conn == null){

			try {

				Class.forName(driver);

				conn = DriverManager.getConnection(url, username, password);

			} catch (ClassNotFoundException e) {

				e.printStackTrace();

			}catch (SQLException e) {

				e.printStackTrace();

			}

		}

		return conn;

	}

	

	//执行查询语句

	public void query(String sql, boolean isSelect) throws SQLException{

		PreparedStatement pstmt;

		

		try {

			pstmt = getConn().prepareStatement(sql);

			//建立一个结果集，用来保存查询出来的结果

			ResultSet rs = pstmt.executeQuery();

			while (rs.next()) {

				String name = rs.getString("name");

				System.out.println(name);

			}

			rs.close();

			pstmt.close();

		} catch (SQLException e) {

			e.printStackTrace();

		}

	}

	

	public void query(String sql) throws SQLException{

		PreparedStatement pstmt;

		pstmt = getConn().prepareStatement(sql);

		pstmt.execute();

		pstmt.close();

	}

	

	

	//关闭连接

	public void close(){

		try {

			getConn().close();

			

		} catch (SQLException e) {

			e.printStackTrace();

		}

	}

	

}



	//数据库连接对象

	private static Connection conn = null;

	

	private static String driver = "oracle.jdbc.driver.OracleDriver"; //驱动

	

	private static String url = "jdbc:oracle:thin:@//127.0.0.1:1521/orcl"; //连接字符串

	

	private static String username = "system"; //用户名

	

	private static String password = "123456"; //密码

	

	

	// 获得连接对象

	private static synchronized Connection getConn(){

		if(conn == null){

			try {

				Class.forName(driver);

				conn = DriverManager.getConnection(url, username, password);

			} catch (ClassNotFoundException e) {

				e.printStackTrace();

			}catch (SQLException e) {

				e.printStackTrace();

			}

		}

		return conn;

	}

	

	//执行查询语句

	public void query(String sql, boolean isSelect) throws SQLException{

		PreparedStatement pstmt;

		

		try {

			pstmt = getConn().prepareStatement(sql);

			//建立一个结果集，用来保存查询出来的结果

			ResultSet rs = pstmt.executeQuery();

			while (rs.next()) {

				String name = rs.getString("name");

				System.out.println(name);

			}

			rs.close();

			pstmt.close();

		} catch (SQLException e) {

			e.printStackTrace();

		}

	}

	

	public void query(String sql) throws SQLException{

		PreparedStatement pstmt;

		pstmt = getConn().prepareStatement(sql);

		pstmt.execute();

		pstmt.close();

	}

	

	

	//关闭连接

	public void close(){

		try {

			getConn().close();

			

		} catch (SQLException e) {

			e.printStackTrace();

		}

	}

	

}

 

5. 创建调用类

 

public class ConnOracle {

	public static void main(String[] args) throws SQLException {

		OracleJdbcTest test = new OracleJdbcTest();

		try {

			test.query("drop table student");

		} catch (SQLException e) {}

		

		test.query("create table student(id int, name nchar(20))");

		

		test.query("insert into student values(1,'zhangsan')");

		

		test.query("insert into student values(2,'lisi')");

		

		test.query("select * from student", true);

		

		test.close();

	}

}



	public static void main(String[] args) throws SQLException {

		OracleJdbcTest test = new OracleJdbcTest();

		try {

			test.query("drop table student");

		} catch (SQLException e) {}

		

		test.query("create table student(id int, name nchar(20))");

		

		test.query("insert into student values(1,'zhangsan')");

		

		test.query("insert into student values(2,'lisi')");

		

		test.query("select * from student", true);

		

		test.close();

	}

}

 

6. 显示结果

 

转载：https://www.cnblogs.com/linlf03/p/8215677.html

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