From 701a08fd9e6288a872ec47773d7dc89711d56823 Mon Sep 17 00:00:00 2001 From: Coding Zhang <2291200076@qq.com> Date: Thu, 20 Jan 2022 14:56:41 +0800 Subject: [PATCH] 2022.01.20 1229 --- 张博凯的Java学习笔记.md | 404 +++++++++++++++++++++++++++++++++++++++- 1 file changed, 403 insertions(+), 1 deletion(-) diff --git a/张博凯的Java学习笔记.md b/张博凯的Java学习笔记.md index 1339caa..c297df5 100644 --- a/张博凯的Java学习笔记.md +++ b/张博凯的Java学习笔记.md @@ -1528,6 +1528,8 @@ password=111111 ##### 导入PageHelper依赖 + + https://mvnrepository.com/artifact/com.github.pagehelper/pagehelper/5.3.0 ```xml @@ -1606,6 +1608,8 @@ https://mvnrepository.com/artifact/com.github.pagehelper/pagehelper/5.3.0 ##### log4j依赖 + + https://mvnrepository.com/artifact/log4j/log4j/1.2.17 ```xml @@ -1621,6 +1625,8 @@ https://mvnrepository.com/artifact/log4j/log4j/1.2.17 ##### 导入log4j.propertites文件 + + [log4j.properties](张博凯的Java学习笔记.assets\file\log4j.properties) src/main/resources/log4j.properties @@ -3506,7 +3512,7 @@ import org.springframework.test.context.junit4.SpringJUnit4ClassRunner; import javax.annotation.Resource; import java.util.List; -@RunWith(SpringJUnit4ClassRunner.class) +@RunWith(SpringJUnit4ClassRunner.class) @ContextConfiguration("classpath:applicationContext.xml") public class SpringUserTest { // 需要调用接口中的方法进行测试 @@ -3523,12 +3529,408 @@ public class SpringUserTest { } ``` +> 通过@RunWith，声明当前测试类位于Spring容器管理 +> +> 通过@ContextConfiguration声明加载配置文件 + 运行结果 ![image-20220120005858883](张博凯的Java学习笔记.assets/image-20220120005858883.png) +#### TKMapper快速开发 + +> tk.mapper是mybatis第三方提供的一个插件。简化接口，不需要映射文件 + +##### 导入依赖 + +> 基于上一个项目（Spring整合MyBatis） + +https://mvnrepository.com/artifact/tk.mybatis/mapper/4.1.5 + +```xml + + + tk.mybatis + mapper + 4.1.5 + +``` + +##### 修改Spring的核心配置文件 + +**去掉以下部分** + +```xml + + + + + + +``` + +**修改以下部分** + +```xml + + +``` + +改为 + +```xml + + +``` + +![image-20220120111645093](张博凯的Java学习笔记.assets/image-20220120111645093.png) + +##### 删除映射文件 + +src/main/resources/mappers/ + +##### 实体类添加注解 + +src/main/java/org/example/entity/User.java + +```java +package org.example.entity; + +import lombok.AllArgsConstructor; +import lombok.Data; +import lombok.NoArgsConstructor; +import tk.mybatis.mapper.annotation.KeySql; + +import javax.persistence.Id; +import javax.persistence.Table; + +@Data +@AllArgsConstructor +@NoArgsConstructor +@Table(name = "user") // 对应数据库表名 +public class User { + /* ***** 如果表中字段名和实体类中属性名一致，就可以直接测试 ***** */ + @Id // 主键 + @KeySql(useGeneratedKeys = true) // 自增 + private Integer user_id; + private String user_name; + private String user_pwd; + private String user_realname; + private Integer user_age; + + /* 其实写成驼峰命名，经测试也可以 */ + @Id // 主键 + @KeySql(useGeneratedKeys = true) // 自增 + private Integer userId; + private String userName; + private String userPwd; + private String userRealname; + private Integer userAge; + + /* ***** 如果表中字段名和实体类中属性名不一致，需要谈价@Column注解 ***** */ + @Id // 主键 + @KeySql(useGeneratedKeys = true) // 自增 + @Column(name = "user_id") + private Integer id; + @Column(name = "user_name") + private String name; + @Column(name = "user_pwd") + private String pwd; + @Column(name = "user_realname") + private String realname; + @Column(name = "user_age") + private Integer age; +} +``` + +##### mapper接口改为extends，接口函数删掉 + +src/main/java/org/example/mapper/UserMapper.java + +```java +package org.example.mapper; + +import org.example.entity.User; +import tk.mybatis.mapper.common.Mapper; + +public interface UserMapper extends Mapper { + +} +``` + +###### 测试类 + +```java +package org.example.test; + +import org.example.entity.User; +import org.example.mapper.UserMapper; +import org.junit.Test; +import org.junit.runner.RunWith; +import org.springframework.test.context.ContextConfiguration; +import org.springframework.test.context.junit4.SpringJUnit4ClassRunner; + +import javax.annotation.Resource; +import java.util.List; + +@RunWith(SpringJUnit4ClassRunner.class) +@ContextConfiguration("classpath:applicationContext.xml") +public class SpringUserTest { + // 需要调用接口中的方法进行测试 + @Resource + private UserMapper userMapper; + + @Test + public void show() { + List users = userMapper.selectAll(); + for (User user : users) { + System.out.println(user); + } + } +} +``` + +运行结果 + +```bash +User(user_id=1, user_name=小明, user_pwd=13579, user_realname=张小明, user_age=20) +User(user_id=2, user_name=ad, user_pwd=asda, user_realname=dasd, user_age=48) + +Process finished with exit code 0 +``` + + + +#### Spring整合MyBatis整合log4j + +> 基于上一个项目（TKMapper快速开发） + +##### 导入依赖 + +[log4j](#log4j依赖)、commons-logging、slf4j-log4j12 + +**导入commons-logging依赖** + +https://mvnrepository.com/artifact/commons-logging/commons-logging/1.2 + +```xml + + + commons-logging + commons-logging + 1.2 + +``` + +**导入slf4j-log4j12依赖** + +https://mvnrepository.com/artifact/org.slf4j/slf4j-log4j12/1.7.25 + +```xml + + + org.slf4j + slf4j-log4j12 + 1.7.25 + test + +``` + +##### 添加log4j配置文件 + +[导入log4j.propertites文件](#导入log4j_propertites文件) + +进行测试，日志成功输出 + +![image-20220120115301780](张博凯的Java学习笔记.assets/image-20220120115301780.png) + + + +#### Spring和MyBatis整合后pageHelper分页插件的使用 + +##### 导入依赖 + +[导入PageHelper依赖](#PageHelper依赖) + +##### 在Spring核心配置文件中配置拦截器 + +https://github.com/pagehelper/Mybatis-PageHelper/blob/master/wikis/zh/HowToUse.md + +src/main/resources/applicationContext.xml + +```xml + + ... + + + + + + + + params=value1 + + + + + + +``` + +##### 测试类 + +src/test/java/org/example/test/SpringUserTest.java + +```java +package org.example.test; + +import com.github.pagehelper.PageHelper; +import com.github.pagehelper.PageInfo; +import org.example.entity.User; +import org.example.mapper.UserMapper; +import org.junit.Test; +import org.junit.runner.RunWith; +import org.springframework.test.context.ContextConfiguration; +import org.springframework.test.context.junit4.SpringJUnit4ClassRunner; + +import javax.annotation.Resource; +import java.util.List; + +@RunWith(SpringJUnit4ClassRunner.class) +@ContextConfiguration("classpath:applicationContext.xml") +public class SpringUserTest { + // 需要调用接口中的方法进行测试 + @Resource + private UserMapper userMapper; + + @Test + public void show() { + // 设置当前页，页面容量 + PageHelper.startPage(1,3); + List users = userMapper.selectAll(); + PageInfo userPageInfo = new PageInfo<>(users); + System.out.println(userPageInfo); + } +} +``` + + + +运行结果 + +```bash +PageInfo{pageNum=1, pageSize=3, size=3, startRow=1, endRow=3, total=5, pages=2, list=Page{count=true, pageNum=1, pageSize=3, startRow=0, endRow=3, total=5, pages=2, reasonable=false, pageSizeZero=false}[User(id=1, name=小明, pwd=13579, realname=张小明, age=20), User(id=2, name=ad, pwd=asda, realname=dasd, age=48), User(id=3, name=vb, pwd=13579, realname=张小明, age=20)], prePage=0, nextPage=2, isFirstPage=true, isLastPage=false, hasPreviousPage=false, hasNextPage=true, navigatePages=8, navigateFirstPage=1, navigateLastPage=2, navigatepageNums=[1, 2]} +``` + + + +#### AOP注解事务的使用 + +##### 导入依赖 + +spring-aspects + +https://mvnrepository.com/artifact/org.springframework/spring-aspects/5.2.19.RELEASE + +```xml + + + org.springframework + spring-aspects + 5.2.19.RELEASE + +``` + + + +##### 修改Spring的核心配置文件 + +修改文件头，添加事务管理器配置 + +```xml + + + + ... + + + + + + + + + + + + + + + +``` + +##### 应用 + +创建UserService + +src/main/java/org/example/service/UserService.java + +```java +package org.example.service; + +import org.springframework.stereotype.Service; +import org.springframework.transaction.annotation.Propagation; +import org.springframework.transaction.annotation.Transactional; + +@Service +public class UserService { + @Transactional(propagation = Propagation.REQUIRED) + public void addUser() { + System.out.println("增加"); + } + @Transactional(propagation = Propagation.REQUIRED) + public int updateUser() { + return 1; + } + @Transactional(propagation = Propagation.SUPPORTS) // 查询不需要事务 + public int selectUser() { + return 1; + } +} +``` + +>**Spring中七种Propagation类的事务属性详解** +> +> REQUIRED：支持当前事务，如果当前没有事务，就新建一个事务。这是最常见的选择。 +> +> SUPPORTS：支持当前事务，如果当前没有事务，就以非事务方式执行。 +> +> MANDATORY：支持当前事务，如果当前没有事务，就抛出异常。 +> +> REQUIRES_NEW：新建事务，如果当前存在事务，把当前事务挂起。 +> +> NOT_SUPPORTED：以非事务方式执行操作，如果当前存在事务，就把当前事务挂起。 +> +> NEVER：以非事务方式执行，如果当前存在事务，则抛出异常。 +> +> NESTED：支持当前事务，如果当前事务存在，则执行一个嵌套事务，如果当前没有事务，就新建一个事务。 + +> REQUIRED和SUPPORTS用的较多。REQUIRED→增删改，SUPPORTS→查 + + + ### SpringMVC框架 > Web框架，Servlet角色