Java學習筆記-- 面向物件2

阿新 • • 發佈：2020-12-10

技術標籤：框架

整體

SQL

DROP TABLE IF EXISTS `user`;
CREATE TABLE `user` (
  `id` int(20) NOT NULL,
  `name` varchar(30) DEFAULT NULL,
  `pwd` varchar(30) DEFAULT NULL,
  PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8;

-- ----------------------------
-- Records of user
-- ----------------------------
INSERT INTO `user` VALUES ('1', '狂神', '123456');
INSERT INTO `user` VALUES ('2', '張三2', 'asdfgh');
INSERT INTO `user` VALUES ('3', '李四', '987654');
INSERT INTO `user` VALUES ('4', '的', 'adsf');

pom.xml

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>com.yao</groupId>
    <artifactId>mybatis</artifactId>
    <version>1.0-SNAPSHOT</version>


    <build>
        <resources>
            <resource>
                <directory>src/main/java</directory>
                <includes>
                    <include>**/*.properties</include>
                    <include>**/*.xml</include>
                </includes>
                <filtering>false</filtering>
            </resource>
            <resource>
                <directory>src/main/resources</directory>
                <includes>
                    <include>**/*.properties</include>
                    <include>**/*.xml</include>
                </includes>
                <filtering>false</filtering>
            </resource>
        </resources>
    </build>


    <dependencies>
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis</artifactId>
            <version>3.5.2</version>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>5.1.47</version>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <version>1.16.10</version>
        </dependency>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.12</version>
        </dependency>
        <dependency>
            <groupId>log4j</groupId>
            <artifactId>log4j</artifactId>
            <version>1.2.17</version>
        </dependency>
    </dependencies>



</project>

db.properties

driver=com.mysql.jdbc.Driver
url=jdbc:mysql://localhost:3306/mybatis?useSSL=true&useUnicode=true&characterEncoding=utf8
username=root
password=123456

log4j.properties

#將等級為DEBUG的日誌資訊輸出到console和file這兩個目的地，console和file的定義在下面的程式碼
log4j.rootLogger=DEBUG,console,file

#控制檯輸出的相關設定
log4j.appender.console = org.apache.log4j.ConsoleAppender
log4j.appender.console.Target = System.out
log4j.appender.console.Threshold=DEBUG
log4j.appender.console.layout = org.apache.log4j.PatternLayout
log4j.appender.console.layout.ConversionPattern=[%c]-%m%n

#檔案輸出的相關設定
log4j.appender.file = org.apache.log4j.RollingFileAppender
log4j.appender.file.File=./log/yao.log
log4j.appender.file.MaxFileSize=10mb
log4j.appender.file.Threshold=DEBUG
log4j.appender.file.layout=org.apache.log4j.PatternLayout
log4j.appender.file.layout.ConversionPattern=[%p][%d{yy-MM-dd}][%c]%m%n

#日誌輸出級別
log4j.logger.org.mybatis=DEBUG
log4j.logger.java.sql=DEBUG
log4j.logger.java.sql.Statement=DEBUG
log4j.logger.java.sql.ResultSet=DEBUG
log4j.logger.java.sql.PreparedStatement=DEBUG

mybatis-config.xml

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE configuration
        PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-config.dtd">
<configuration>



    <properties resource="db.properties"/>

    <!--標準日誌實現-->
    <!--<settings>-->
        <!--<setting name="logImpl" value="STDOUT_LOGGING"/>-->
    <!--</settings>-->

    <!--通過使用Log4j，我們可以控制日誌資訊輸送的目的地：控制檯，文字，GUI元件....-->
    <settings>
        <setting name="logImpl" value="STDOUT_LOGGING"/>
    </settings>

    <!--配置別名,注意順序-->
    <typeAliases>
        <typeAlias type="com.yao.pojo.User" alias="User"/>
    </typeAliases>


    <environments default="development">
        <environment id="development">
            <transactionManager type="JDBC"/>
            <dataSource type="POOLED">
                <property name="driver" value="com.mysql.jdbc.Driver"/>
                <property name="url" value="jdbc:mysql://192.168.182.153:3306/mybatis?useSSL=false&amp;useUnicode=true&amp;characterEncoding=utf8"/>
                <!--<property name="url" value="jdbc:mysql://192.168.182.153:3306/mybatis?useSSL=true&amp;useUnicode=true&amp;characterEncoding=utf8"/>-->
                <property name="username" value="${username}"/>
                <property name="password" value="jarvis123456"/>
            </dataSource>
        </environment>
    </environments>


    <mappers>
        <mapper resource="com/yao/dao/UserMapper.xml"/>
    </mappers>


</configuration>

MybatisUtils

package com.yao.utils;

import org.apache.ibatis.io.Resources;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;
import java.io.IOException;
import java.io.InputStream;

public class MybatisUtils {

    private static SqlSessionFactory sqlSessionFactory;

    static {
        try {
            String resource = "mybatis-config.xml";
            InputStream inputStream = Resources.getResourceAsStream(resource);
            sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream);
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    //獲取SqlSession連線
    public static SqlSession getSession(){
        return sqlSessionFactory.openSession();
    }

}

User

package com.yao.pojo;

import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;

/**
 * @author
 * @date 2020/12/7 11:55
 */
@Data
@AllArgsConstructor
@NoArgsConstructor

public class User {
    private int id;  //id
    private String name;   //姓名
    private String psd;   //密碼

}

UserDao Interface

package com.yao.dao;

import com.yao.pojo.User;
import org.apache.ibatis.annotations.Param;

import java.util.List;
import java.util.Map;

/**
 * @author
 * @date 2020/12/7 11:57
 */
public interface UserDao {
    List<User> selectUser();
    //根據id查詢使用者
    User selectUserById(int id);
    User selectUserByNP(@Param("username") String username, @Param("pwd") String pwd);
    User selectUserByNP2(Map<String,Object> map);
    int addUser(User user);
    //修改一個使用者
    int updateUser(User user);
    //根據id刪除使用者
    int deleteUser(int id);
    User selectlike(@Param("username") String username);
    User selectlike2(@Param("username") String username);//會sql注入
    //選擇全部使用者實現分頁
    List<User> selectUser2(Map<String,Integer> map);

}

UserDaoImpl

package com.yao.dao;

import com.yao.pojo.User;

import java.util.List;
import java.util.Map;

/**
 * @author
 * @date 2020/12/7 14:03
 */
public class UserDaoImpl implements UserDao {

    public List<User> selectUser() {
        return null;
    }

    public User selectUserById(int id) {
        return null;
    }

    public User selectUserByNP(String username, String pwd) {
        return null;
    }

    public User selectUserByNP2(Map<String, Object> map) {
        return null;
    }

    public int addUser(User user) {
        return 0;
    }

    public int updateUser(User user) {
        return 0;
    }

    public int deleteUser(int id) {
        return 0;
    }

    public User selectlike(String username) {
        return null;
    }

    public User selectlike2(String username) {
        //會sql注入
        return null;
    }

    public List<User> selectUser2(Map<String, Integer> map) {
        return null;
    }
}

UserMapper.xml

package com.yao.dao;

import com.yao.pojo.User;

import java.util.List;
import java.util.Map;

/**
 * @author
 * @date 2020/12/7 14:03
 */
public class UserDaoImpl implements UserDao {

    public List<User> selectUser() {
        return null;
    }

    public User selectUserById(int id) {
        return null;
    }

    public User selectUserByNP(String username, String pwd) {
        return null;
    }

    public User selectUserByNP2(Map<String, Object> map) {
        return null;
    }

    public int addUser(User user) {
        return 0;
    }

    public int updateUser(User user) {
        return 0;
    }

    public int deleteUser(int id) {
        return 0;
    }

    public User selectlike(String username) {
        return null;
    }

    public User selectlike2(String username) {
        //會sql注入
        return null;
    }

    public List<User> selectUser2(Map<String, Integer> map) {
        return null;
    }
}

MyTest

import com.yao.dao.UserDao;
import com.yao.pojo.User;
import com.yao.utils.MybatisUtils;
import org.apache.ibatis.session.SqlSession;
import org.junit.Test;
import org.apache.log4j.Logger;

import java.util.HashMap;
import java.util.List;
import java.util.Map;

public class MyTest {
    @Test
    public void selectUser() {
        SqlSession session = MybatisUtils.getSession();
        //方法一,不推薦:
        List<User> users = session.selectList("com.yao.dao.UserDao.selectUser");
//        List<User> users = session.selectOne("com.yao.dao.UserDao.selectUser");
        //方法二:
//      UserDao mapper = session.getMapper(UserDao.class);
//      List<User> users = mapper.selectUser();
        for (User user: users){
            System.out.println(user);
        }
        session.close();
    }

    @Test
    public void tsetSelectUserById() {
        SqlSession session = MybatisUtils.getSession();  //獲取SqlSession連線
        UserDao mapper = session.getMapper(UserDao.class);
        User user = mapper.selectUserById(1);
        System.out.println(user);
        session.close();
    }

    @Test
    public void tsetSelectUserByNP() {
        SqlSession session = MybatisUtils.getSession();  //獲取SqlSession連線
        UserDao mapper = session.getMapper(UserDao.class);
        User user = mapper.selectUserByNP("張三2","abcdef");
        System.out.println(user);
        session.close();
    }

    @Test
    public void tsetSelectUserByNP2() {
        SqlSession session = MybatisUtils.getSession();  //獲取SqlSession連線
        UserDao mapper = session.getMapper(UserDao.class);
        Map<String, Object> map = new HashMap<String, Object>();
        map.put("username","狂神");
        map.put("pwd","123456");
        User user = mapper.selectUserByNP2(map);
        System.out.println(user);
        session.close();
    }

    @Test
    public void testAddUser() {
        SqlSession session = MybatisUtils.getSession();
        UserDao mapper = session.getMapper(UserDao.class);
        User user = new User(5,"王五","zxcvbn");
        int i = mapper.addUser(user);
        System.out.println(i);
        session.commit(); //提交事務,重點!不寫的話不會提交到資料庫
        session.close();
    }

    @Test
    public void testUpdateUser() {
        SqlSession session = MybatisUtils.getSession();
        UserDao mapper = session.getMapper(UserDao.class);
        User user = mapper.selectUserById(2);
        user.setPsd("asdfgh");
        int i = mapper.updateUser(user);
        System.out.println(i);
        session.commit(); //提交事務,重點!不寫的話不會提交到資料庫
        session.close();
    }

    @Test
    public void testDeleteUser() {
        SqlSession session = MybatisUtils.getSession();
        UserDao mapper = session.getMapper(UserDao.class);
        int i = mapper.deleteUser(5);
        System.out.println(i);
        session.commit(); //提交事務,重點!不寫的話不會提交到資料庫
        session.close();
    }

    @Test
    public void selectlike() {
        SqlSession session = MybatisUtils.getSession();  //獲取SqlSession連線
        UserDao mapper = session.getMapper(UserDao.class);
        String wildcardname = "%三%";
        User user = mapper.selectlike(wildcardname);
        System.out.println(user);
        session.close();
    }

    @Test
    //可能會sql注入
    public void selectlike2() {
        SqlSession session = MybatisUtils.getSession();  //獲取SqlSession連線
        UserDao mapper = session.getMapper(UserDao.class);
        String wildcardname = "%三%";
        User user = mapper.selectlike2(wildcardname);
        System.out.println(user);
        session.close();
    }

    //注意導包：org.apache.log4j.Logger
    static Logger logger = Logger.getLogger(MyTest.class);

    @Test
    public void selectUser2() {
        logger.info("info：進入selectUser方法");
        logger.debug("debug：進入selectUser方法");
        logger.error("error: 進入selectUser方法");
        SqlSession session = MybatisUtils.getSession();
        UserDao mapper = session.getMapper(UserDao.class);
        List<User> users = mapper.selectUser();
        for (User user: users){
            System.out.println(user);
        }
        session.close();
    }

    //分頁查詢 , 兩個引數startIndex , pageSize
    @Test
    public void testSelectUser2() {
        SqlSession session = MybatisUtils.getSession();
        UserDao mapper = session.getMapper(UserDao.class);

//        int currentPage = 1;  //第幾頁
//        int pageSize = 2;  //每頁顯示幾個
//        Map<String,Integer> map = new HashMap<String,Integer>();
//        map.put("startIndex",(currentPage-1)*pageSize);
//        map.put("pageSize",pageSize);

        int currentPage = 2;  //從哪一行開始
        int pageSize = 2;  //幾個
        Map<String,Integer> map = new HashMap<String,Integer>();
        map.put("startIndex",currentPage);
        map.put("pageSize",pageSize);

        List<User> users = mapper.selectUser2(map);

        for (User user: users){
            System.out.println(user);
        }

        session.close();
    }

}