分享程序员开发的那些事...
更新时间：2022-03-29 06:32:39
前几天没事翻看了一下JDBC，顺便写了一个小demo。demo代码如下：
package com.zkn.newlearn.jdbc.mysql.first;
import org.junit.Test;
import java.io.IOException;
import java.io.InputStream;
import java.sql.*;
import java.util.Properties;
/**
* Created by zkn on 2017/5/2.
*/
public class MySqlJDBC {
/**
* 数据库连接
*/
private static String URL;
/**
* 用户名
*/
private static String USER_NAME;
/**
* 密码
*/
private static String PASS_WORD;
/**
* 存放属性信息
*/
private static Properties properties = new Properties();
static {
InputStream is = MySqlJDBC.class.getResourceAsStream("driver.properties");
try {
properties.load(is);
URL = (String)properties.get("url");
USER_NAME = (String)properties.get("userName");
PASS_WORD = (String)properties.get("passWord");
} catch (IOException e) {
e.printStackTrace();
}
}
/**
* 查询操作
*/
@Test
public void testStatementQuery() {
Connection connection = null;
Statement statement = null;
ResultSet resultSet = null;
try {
//加载连接 这里会导致类的初始化
Class.forName("com.mysql.jdbc.Driver");
//获取数据库驱动
connection = DriverManager.getConnection(URL, USER_NAME, PASS_WORD);
//获取sql的声明
statement = connection.createStatement();
//执行查询的操作
resultSet = statement.executeQuery("SELECT * FROM TABLE_NAME");
//取出查询出来的数据
StringBuilder sb = new StringBuilder();
while (resultSet.next()) {
sb.append(resultSet.getLong("id")).append(" ");
//这里需要注意的是下标是从1开始的，不是从0开始的
sb.append(resultSet.getString(2)).append(" ");
sb.append(resultSet.getString("gmt_create")).append(" ");
System.out.println(sb.toString());
//清空原来的数据
sb.delete(0, sb.length());
}
} catch (ClassNotFoundException e) {
e.printStackTrace();
} catch (SQLException e) {
e.printStackTrace();
} finally {
if (resultSet != null) {
try {
resultSet.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
//关闭sql声明
if (statement != null) {
try {
statement.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
//关闭连接
if (connection != null) {
try {
connection.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
}
}
/**
* 预编译查询
*/
@Test
public void testPreparedStatement() {
Connection connection = null;
PreparedStatement pst = null;
ResultSet resultSet = null;
try {
//加载驱动
Class.forName("com.mysql.jdbc.Driver");
//获取连接
connection = DriverManager.getConnection(URL, USER_NAME, PASS_WORD);
String sql = "SELECT * FROM TABLE_NAME WHERE EMPID = ?";
//获取sql声明
pst = connection.prepareStatement(sql);
//pst.setLong(1,2);
//封装查询条件
pst.setString(1, "32151");
//执行sql的操作
resultSet = pst.executeQuery();
StringBuilder sb = new StringBuilder();
while (resultSet.next()) {
sb.append(resultSet.getLong("id")).append(" ");
sb.append(resultSet.getString(2));
System.out.println(sb.toString());
//清空原来的数据
sb.delete(0, sb.length());
}
} catch (ClassNotFoundException e) {
e.printStackTrace();
} catch (SQLException e) {
e.printStackTrace();
} finally {
if (resultSet != null) {
try {
resultSet.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
if (pst != null) {
try {
pst.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
if (connection != null) {
try {
connection.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
}
}
/**
* 单条插入
*/
@Test
public void testInsert() {
Connection connection = null;
PreparedStatement pst = null;
ResultSet resultSet = null;
try {
//加载驱动
Class.forName("com.mysql.jdbc.Driver");
//获取连接
connection = DriverManager.getConnection(URL, USER_NAME, PASS_WORD);
//自动提交为false
connection.setAutoCommit(false);
//创建sql声明
pst = connection.prepareStatement(
"INSERT INTO TABLE_NAME (NAME,EMPID,ORG_ID,ORG_CODE,IS_ADMIN,GMT_CREATE,GMT_MODIFIED) VALUES (?,"
+ "?,?,?,?,now(),now())",
Statement.RETURN_GENERATED_KEYS);
pst.setString(1, "张三");
pst.setString(2, "784550");
pst.setLong(3, 2);
pst.setString(4, "0.1.2");
pst.setInt(5, 1);
//执行插入操作
int count = pst.executeUpdate();
if (count > 0) {
System.out.println("插入成功!");
} else {
System.out.println("插入失败!");
}
resultSet = pst.getGeneratedKeys();
while (resultSet.next()) {
System.out.println(String.format("主键值为%d", resultSet.getLong(1)));
}
//提交操作
connection.commit();
} catch (ClassNotFoundException e) {
e.printStackTrace();
} catch (SQLException e) {
e.printStackTrace();
//异常回滚
try {
connection.rollback();
} catch (SQLException ee) {
ee.printStackTrace();
}
} finally {
if (resultSet != null) {
try {
resultSet.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
if (pst != null) {
try {
pst.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
if (connection != null) {
try {
connection.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
}
}
/**
* 批量插入 需要设置 rewriteBatchedStatements=true
*/
@Test
public void testBatchInsert() {
Connection connection = null;
PreparedStatement pst = null;
ResultSet resultSet = null;
try {
//加载驱动
Class.forName("com.mysql.jdbc.Driver");
//获取连接
connection = DriverManager.getConnection(URL, USER_NAME, PASS_WORD);
//自动提交为false
connection.setAutoCommit(false);
//创建sql声明
pst = connection.prepareStatement(
"INSERT INTO TABLE_NAME (NAME,EMPID,ORG_ID,ORG_CODE,IS_ADMIN,GMT_CREATE,GMT_MODIFIED) VALUES (?,"
+ "?,?,?,?,now(),now())",
Statement.RETURN_GENERATED_KEYS);
for (int i = 0; i < 10; i++) {
pst.setString(1, "张三");
pst.setString(2, "784550");
pst.setLong(3, 2);
pst.setString(4, "0.1.2");
pst.setInt(5, 1);
pst.addBatch();
}
int[] count = pst.executeBatch();
if (count != null && count.length > 0) {
System.out.println("插入成功!");
} else {
System.out.println("插入失败!");
}
resultSet = pst.getGeneratedKeys();
while (resultSet.next()) {
System.out.println(String.format("主键值为%d", resultSet.getLong(1)));
}
//提交操作
connection.commit();
} catch (ClassNotFoundException e) {
e.printStackTrace();
} catch (SQLException e) {
e.printStackTrace();
//异常回滚
try {
connection.rollback();
} catch (SQLException ee) {
ee.printStackTrace();
}
} finally {
if (resultSet != null) {
try {
resultSet.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
if (pst != null) {
try {
pst.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
if (connection != null) {
try {
connection.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
}
}
/**
* 测试更新操作
*/
@Test
public void testUpdate() {
Connection connection = null;
PreparedStatement pst = null;
try {
//加载驱动
Class.forName("com.mysql.jdbc.Driver");
//获取连接
connection = DriverManager.getConnection(URL, USER_NAME, PASS_WORD);
//自动提交为false
connection.setAutoCommit(false);
//创建sql声明
pst = connection.prepareStatement("update TABLE_NAME set name = ? where id >=? and id <= ? ");
pst.setString(1, "李思思");
pst.setLong(2, 1972);
pst.setLong(3, 1995);
int count = pst.executeUpdate();
if (count > 0) {
System.out.println("更新成功!");
} else {
System.out.println("更新失败");
return;
}
//提交操作
connection.commit();
} catch (ClassNotFoundException e) {
e.printStackTrace();
} catch (SQLException e) {
e.printStackTrace();
//异常回滚
try {
connection.rollback();
} catch (SQLException ee) {
ee.printStackTrace();
}
} finally {
if (pst != null) {
try {
pst.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
if (connection != null) {
try {
connection.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
}
}
/**
* 测试删除操作
*/
@Test
public void testDelete() {
Connection connection = null;
PreparedStatement pst = null;
try {
//加载驱动
Class.forName("com.mysql.jdbc.Driver");
//获取连接
connection = DriverManager.getConnection(URL, USER_NAME, PASS_WORD);
//自动提交为false
connection.setAutoCommit(false);
//创建sql的声明
pst = connection.prepareStatement("DELETE FROM TABLE_NAME WHERE ID >=? AND ID <=? ");
pst.setLong(1, 1972);
pst.setLong(2, 1995);
//执行sql
pst.executeUpdate();
//提交
connection.commit();
} catch (ClassNotFoundException e) {
e.printStackTrace();
} catch (SQLException e) {
e.printStackTrace();
//异常回滚
try {
connection.rollback();
} catch (SQLException ee) {
ee.printStackTrace();
}
} finally {
if (pst != null) {
try {
pst.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
if (connection != null) {
try {
connection.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
}
}
}
url=jdbc:mysql://localhost:3306/数据库?useUnicode=true&characterEncoding=UTF-8&serverTimezone=UTC&rewriteBatchedStatements=true userName= passWord=在这里遇到了一个问题Caused by: com.mysql.cj.core.exceptions.InvalidConnectionAttributeException: The server time zone value '�й���ʱ��' is unrecognized or represents more than one time zone. You must configure either the server or JDBC driver (via the serverTimezone configuration property) to use a more specifc time zone value if you want to utilize time zone support. 解决办法是在url连接中加上serverTimezone=UTC。