Spring学习（六）

发表于 2023-07-26 更新于 2023-08-16 分类于计算机学习，框架， Spring 阅读次数：

Jdbc模板测试

package com.xiaoguan.bean;

import javax.sql.DataSource;
import java.io.PrintWriter;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
import java.sql.SQLFeatureNotSupportedException;
import java.util.logging.Logger;

public class MyDataSource implements DataSource {
    private String driver;
    private String url;
    private String username;
    private String password;

    public void setDriver(String driver) {
        this.driver = driver;
    }

    public void setUrl(String url) {
        this.url = url;
    }

    public void setUsername(String username) {
        this.username = username;
    }

    public void setPassword(String password) {
        this.password = password;
    }

    @Override
    public Connection getConnection() throws SQLException {
        try {
            Class.forName(driver);
            Connection connection = DriverManager.getConnection(url, username, password);
            return connection;
        } catch (Exception e) {
            e.printStackTrace();
        }
        return null;
    }

    @Override
    public Connection getConnection(String username, String password) throws SQLException {
        return null;
    }

    @Override
    public PrintWriter getLogWriter() throws SQLException {
        return null;
    }

    @Override
    public void setLogWriter(PrintWriter out) throws SQLException {

    }

    @Override
    public void setLoginTimeout(int seconds) throws SQLException {

    }

    @Override
    public int getLoginTimeout() throws SQLException {
        return 0;
    }

    @Override
    public Logger getParentLogger() throws SQLFeatureNotSupportedException {
        return null;
    }

    @Override
    public <T> T unwrap(Class<T> iface) throws SQLException {
        return null;
    }

    @Override
    public boolean isWrapperFor(Class<?> iface) throws SQLException {
        return false;
    }
}

package com.xiaoguan.bean;

import java.util.Objects;

public class User {
    private Integer id;
    private String realName;
    private Integer age;

    @Override
    public String toString() {
        return "User{" +
                "id=" + id +
                ", realName='" + realName + '\'' +
                ", age=" + age +
                '}';
    }

    @Override
    public boolean equals(Object o) {
        if (this == o) return true;
        if (o == null || getClass() != o.getClass()) return false;
        User user = (User) o;
        return Objects.equals(getId(), user.getId()) && Objects.equals(getRealName(), user.getRealName()) && Objects.equals(getAge(), user.getAge());
    }

    @Override
    public int hashCode() {
        return Objects.hash(getId(), getRealName(), getAge());
    }

    public Integer getId() {
        return id;
    }

    public void setId(Integer id) {
        this.id = id;
    }

    public String getRealName() {
        return realName;
    }

    public void setRealName(String realName) {
        this.realName = realName;
    }

    public Integer getAge() {
        return age;
    }

    public void setAge(Integer age) {
        this.age = age;
    }

    public User(Integer id, String realName, Integer age) {
        this.id = id;
        this.realName = realName;
        this.age = age;
    }

    public User() {
    }
}

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd">
<!--    <bean id="ds" class="com.xiaoguan.bean.MyDataSource">&lt;!&ndash;配置自己的连接池&ndash;&gt;-->
<!--        <property name="driver" value="com.mysql.cj.jdbc.Driver"/>-->
<!--        <property name="url" value="jdbc:mysql://localhost:3306/spring6"/>-->
<!--        <property name="username" value="root"/>-->
<!--        <property name="password" value="68963120g"/>-->
<!--    </bean>-->
    <bean id="ds" class="com.alibaba.druid.pool.DruidDataSource"><!--配置自己的连接池-->
        <property name="driverClassName" value="com.mysql.cj.jdbc.Driver"/>
        <property name="url" value="jdbc:mysql://localhost:3306/spring6"/>
        <property name="username" value="root"/>
        <property name="password" value="68963120g"/>
    </bean>
    <bean id="jdbcTemplate" class="org.springframework.jdbc.core.JdbcTemplate">
        <property name="dataSource" ref="ds"/>
    </bean>
</beans>

package com.xiaoguan.test;

import com.xiaoguan.bean.User;
import org.junit.Test;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import org.springframework.dao.DataAccessException;
import org.springframework.jdbc.core.BeanPropertyRowMapper;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.jdbc.core.PreparedStatementCallback;

import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;

public class JDBCTemplateTest {
    @Test
    public  void testCallback(){
        ApplicationContext applicationContext=new ClassPathXmlApplicationContext("spring.xml");
        JdbcTemplate jdbcTemplate = applicationContext.getBean("jdbcTemplate", JdbcTemplate.class);
        String sql="select id,real_name,age from t_user where id=?";
        User u = jdbcTemplate.execute(sql, new PreparedStatementCallback<User>() {
            @Override
            public User doInPreparedStatement(PreparedStatement ps) throws SQLException, DataAccessException {
                User user = new User();
                ps.setInt(1, 2);
                ResultSet resultSet = ps.executeQuery();
                if (resultSet.next()) {
                    int id = resultSet.getInt("id");
                    String name = resultSet.getString("real_name");
                    int age = resultSet.getInt("age");
                    user.setId(id);
                    user.setAge(age);
                    user.setRealName(name);
                }
                return user;
            }
        });
        System.out.println(u);

    }
    @Test
    public void testBatchDelete(){
        ApplicationContext applicationContext=new ClassPathXmlApplicationContext("spring.xml");
        JdbcTemplate jdbcTemplate = applicationContext.getBean("jdbcTemplate", JdbcTemplate.class);
        String sql="delete from t_user where id=?";
        Object[] objects1={5};
        Object[] objects2={6};
        Object[] objects3={7};
        List<Object[]> list=new ArrayList<>();
        list.add(objects1);
        list.add(objects2);
        list.add(objects3);
        int[] ints = jdbcTemplate.batchUpdate(sql, list);
        System.out.println(Arrays.toString(ints));

    }
    @Test
    public void testBatchUpdaate(){
        ApplicationContext applicationContext=new ClassPathXmlApplicationContext("spring.xml");
        JdbcTemplate jdbcTemplate = applicationContext.getBean("jdbcTemplate", JdbcTemplate.class);
        String sql="update t_user set real_name=?,age=? where id=?";
        Object[] objects1={"小明1",18,4};
        Object[] objects2={"小明2",19,5};
        Object[] objects3={"小明3",20,6};
        List<Object[]> list=new ArrayList<>();
        list.add(objects1);
        list.add(objects2);
        list.add(objects3);
        int[] ints = jdbcTemplate.batchUpdate(sql,list);
        System.out.println(Arrays.toString(ints));
    }
    @Test
    public void testBatchInsert(){
        ApplicationContext applicationContext=new ClassPathXmlApplicationContext("spring.xml");
        JdbcTemplate jdbcTemplate = applicationContext.getBean("jdbcTemplate", JdbcTemplate.class);
        String sql="insert into t_user (real_name,age) values(?,?)";
        Object[] objects1={"小花1",31};
        Object[] objects2={"小花2",32};
        Object[] objects3={"小花3",33};
        Object[] objects4={"小花4",34};
        List<Object[]> list=new ArrayList<>();
        list.add(objects1);
        list.add(objects2);
        list.add(objects3);
        list.add(objects4);
        int[] count = jdbcTemplate.batchUpdate(sql, list);
        System.out.println(Arrays.toString(count));
    }
    @Test
    public void testQueryOneValue(){
        ApplicationContext applicationContext=new ClassPathXmlApplicationContext("spring.xml");
        JdbcTemplate jdbcTemplate = applicationContext.getBean("jdbcTemplate", JdbcTemplate.class);
        String sql="select count(1) from t_user";
        Integer total = jdbcTemplate.queryForObject(sql, int.class);
        System.out.println(total);

    }
    @Test
    public void testSelectAll(){
        ApplicationContext applicationContext=new ClassPathXmlApplicationContext("spring.xml");
        JdbcTemplate jdbcTemplate = applicationContext.getBean("jdbcTemplate", JdbcTemplate.class);
        String sql="select id,real_name,age from t_user ";
        List<User> users = jdbcTemplate.query(sql, new BeanPropertyRowMapper<>(User.class));
        System.out.println(users);
    }
    @Test
    public void testSelectOne(){
        ApplicationContext applicationContext=new ClassPathXmlApplicationContext("spring.xml");
        JdbcTemplate jdbcTemplate = applicationContext.getBean("jdbcTemplate", JdbcTemplate.class);
        String sql="select id,real_name,age from t_user where id=?";
        User user = jdbcTemplate.queryForObject(sql, new BeanPropertyRowMapper<>(User.class),2);
        System.out.println(user);
    }
    @Test
    public void testDelete(){
        ApplicationContext applicationContext=new ClassPathXmlApplicationContext("spring.xml");
        JdbcTemplate jdbcTemplate = applicationContext.getBean("jdbcTemplate", JdbcTemplate.class);
        String sql="delete from t_user where id=?";
        int count = jdbcTemplate.update(sql, 1);
        System.out.println(count);
    }
    @Test
    public void testUpdate(){
        ApplicationContext applicationContext=new ClassPathXmlApplicationContext("spring.xml");
        JdbcTemplate jdbcTemplate = applicationContext.getBean("jdbcTemplate", JdbcTemplate.class);
        String sql="update t_user set real_name=?,age=? where id =?";
        int count = jdbcTemplate.update(sql, "小关", 22, 1);
        System.out.println(count);
    }
    @Test
    public void testInsert(){
        ApplicationContext applicationContext=new ClassPathXmlApplicationContext("spring.xml");
        JdbcTemplate jdbcTemplate = applicationContext.getBean("jdbcTemplate", JdbcTemplate.class);
        String sql="insert into t_user (real_name,age) values(?,?)";
        int count = jdbcTemplate.update(sql, "王五", 32);
        System.out.println(count);
    }
    @Test
    public void testDataSource(){
        ApplicationContext applicationContext=new ClassPathXmlApplicationContext("spring.xml");
        JdbcTemplate jdbcTemplate = applicationContext.getBean("jdbcTemplate", JdbcTemplate.class);
        System.out.println(jdbcTemplate);
    }
}

代理模式

package com.xiaoguan.proxy.client;

import com.xiaoguan.proxy.service.OrderService;
import com.xiaoguan.proxy.service.OrderServiceImpl;
import com.xiaoguan.proxy.service.OrderServiceImplSub;
import com.xiaoguan.proxy.service.OrderServiceProxy;

public class Test {
    public static void main(String[] args) {
//        OrderService orderService=new OrderServiceImpl();
//        orderService.generate();
//        orderService.detail();
//        orderService.modify();

//        OrderService orderService=new OrderServiceImplSub();
//        orderService.generate();
//        orderService.detail();
//        orderService.modify();
        OrderService target=new OrderServiceImpl();
        OrderService proxy=new OrderServiceProxy(target);
        proxy.generate();
        proxy.modify();
        proxy.detail();

    }
}

package com.xiaoguan.proxy.service;

public interface OrderService {
    void generate();
    void modify();
    void detail();

}

package com.xiaoguan.proxy.service;

public class OrderServiceImpl implements OrderService{
    @Override
    public void generate() {
        try {
            Thread.sleep(1234);
            System.out.println("订单已经生成");
        } catch (InterruptedException e) {
            e.printStackTrace();
        }

    }

    @Override
    public void modify() {
        try {
            Thread.sleep(456);
            System.out.println("订单已经修改");
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
    }

    @Override
    public void detail() {
        try {
            Thread.sleep(456);
            System.out.println("请看订单详情");
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
    }
}

package com.xiaoguan.proxy.service;

public class OrderServiceImplSub extends OrderServiceImpl{
    @Override
    public void generate() {
        long begin =System.currentTimeMillis();
        super.generate();
        long end=System.currentTimeMillis();
        System.out.println("耗时为毫秒：" + (end - begin));
    }

    @Override
    public void modify() {
        long begin =System.currentTimeMillis();
        super.modify();
        long end=System.currentTimeMillis();
        System.out.println("耗时为毫秒：" + (end - begin));
    }

    @Override
    public void detail() {
        long begin =System.currentTimeMillis();
        super.detail();
        long end=System.currentTimeMillis();
        System.out.println("耗时为毫秒：" + (end - begin));
    }
}

package com.xiaoguan.proxy.service;

public class OrderServiceProxy implements OrderService  {
    //代理对象
    private OrderService target;

    public OrderServiceProxy(OrderService target) {
        this.target = target;
    }

    @Override
    public void generate() {
        long begin =System.currentTimeMillis();
        target.generate();
        long end=System.currentTimeMillis();
        System.out.println("时间为：" + (end - begin));
    }

    @Override
    public void modify() {
        long begin =System.currentTimeMillis();
        target.modify();
        long end=System.currentTimeMillis();
        System.out.println("时间为：" + (end- begin));
    }

    @Override
    public void detail() {
        long begin =System.currentTimeMillis();
        target.detail();
        long end=System.currentTimeMillis();
        System.out.println("时间为：" + (end - begin));
    }
}

package com.xiaoguan.client;

import com.xiaoguan.proxy.OrderService;
import com.xiaoguan.proxy.OrderServiceImpl;
import com.xiaoguan.proxy.TimeInvocationHander;

import java.lang.reflect.Proxy;

public class Client {
    public static void main(String[] args) {
        OrderService target=new OrderServiceImpl();
        Object proxyObj = Proxy.newProxyInstance(target.getClass().getClassLoader(), target.getClass().getInterfaces(), new TimeInvocationHander(target));
        OrderService obj = (OrderService) proxyObj;
        obj.generate();
        obj.modify();
        obj.detail();
        String name = obj.getName();
        System.out.println(name);

    }
}

package com.xiaoguan.proxy;

public interface OrderService {
    void generate();
    void modify();
    void detail();
    String getName();

}

package com.xiaoguan.proxy;

public class OrderServiceImpl implements OrderService{
    @Override
    public void generate() {
        try {
            Thread.sleep(1234);
            System.out.println("订单已经生成");
        } catch (InterruptedException e) {
            e.printStackTrace();
        }

    }

    @Override
    public void modify() {
        try {
            Thread.sleep(456);
            System.out.println("订单已经修改");
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
    }

    @Override
    public void detail() {
        try {
            Thread.sleep(456);
            System.out.println("请看订单详情");
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
    }

    @Override
    public String getName() {
        System.out.println("getName方法执行了");
        return "张三";
    }
}

package com.xiaoguan.proxy;

import java.lang.reflect.InvocationHandler;
import java.lang.reflect.Method;

/**
 * 第一个参数proxy:代理对象的引用，使用比较少
 * 第二个参数method:目标对象上的目标方法
 * 第三个参数args:目标方法上的实参
 */
public class TimeInvocationHander implements InvocationHandler {
    private Object target;
    public TimeInvocationHander(Object target) {
        this.target=target;
    }

    @Override
    public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
        Long begin=System.currentTimeMillis();
        Object rs = method.invoke(target, args);
        long end=System.currentTimeMillis();
        System.out.println("耗时毫秒：" + (end - begin));
        return rs;
    }
}

package com.xiaoguan.utils;

import com.xiaoguan.proxy.TimeInvocationHander;

import java.lang.reflect.Proxy;

public class ProxyUtil {
    public static Object newProxyInstance(Object target){
        Object proxyObj = Proxy.newProxyInstance(target.getClass().getClassLoader(),
                target.getClass().getInterfaces(),
                new TimeInvocationHander(target));
        return proxyObj;

    }
}

package com.xiaoguan.client;
import com.xiaoguan.proxy.TimerMethodInterceptor;
import com.xiaoguan.proxy.UserService;
import net.sf.cglib.proxy.Enhancer;

public class Client {
    public static void main(String[] args) {
        Enhancer enhancer = new Enhancer();
        enhancer.setSuperclass(UserService.class);
        enhancer.setCallback(new TimerMethodInterceptor());
        UserService userService = (UserService) enhancer.create();
        boolean admin = userService.login("admin", "123");
        System.out.println(admin);
        userService.logout();
    }
}

package com.xiaoguan.proxy;

import net.sf.cglib.proxy.MethodInterceptor;
import net.sf.cglib.proxy.MethodProxy;

import java.lang.reflect.Method;

public class TimerMethodInterceptor implements MethodInterceptor {
    @Override
    public Object intercept(Object o, Method method, Object[] objects, MethodProxy methodProxy) throws Throwable {
        long begin=System.currentTimeMillis();
        Object o1 = methodProxy.invokeSuper(o, objects);
        long end=System.currentTimeMillis();
        System.out.println("耗时" + (end - begin) + "毫秒");
        return o1;
    }
}

package com.xiaoguan.proxy;

public class UserService {
    public boolean login(String username,String password){
        System.out.println("系统正在验证身份");
        if ("admin".equals(username)&&"123".equals(password)) {
            return true;
        }
        return false;
    }
    public void logout(){
        System.out.println("系统正在退出");
    }
}