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IDEA设置代码快捷联想键的方法
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控制台运行java的jar包的方法
控制台运行JAVA项目的方法(先将项目打包)
单环境时, 只有一个配置文件
运行命令：java -jar 项目的名称
单环境时, 有多个配置文件
语法结构：application-{profile}.properties/yml
profile：代表某个配置环境的标识
示例：application-dev.properties/yml 开发环境
application-test.properties/yml 测试环境
application-prod.properties/yml 生产环境
启动命令:java -jar xxx.jar --spring.profiles.active={profile}
Maven项目的POM.XML文件
<?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 https://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.2.1.RELEASE</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<groupId>com.sxt</groupId>
<artifactId>springdata-jpa</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>springdata-jpa</name>
<description>Demo project for Spring Boot</description>
<properties>
<java.version>1.8</java.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-thymeleaf</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-devtools</artifactId>
<scope>runtime</scope>
<optional>true</optional>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-jpa</artifactId>
</dependency>
<dependency>
<groupId>mysql</groupId>
<artifactId>mysql-connector-java</artifactId>
<scope>runtime</scope>
<version>5.1.38</version>
</dependency>
<dependency>
<groupId>com.alibaba</groupId>
<artifactId>druid</artifactId>
<version>1.1.12</version>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>
<exclusions>
<exclusion>
<groupId>org.junit.vintage</groupId>
<artifactId>junit-vintage-engine</artifactId>
</exclusion>
</exclusions>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
</project>
application.properties
#配置数据源信息
spring.datasource.driver-class-name=com.mysql.jdbc.Driver
spring.datasource.url=jdbc:mysql://localhost:3306/jpa
spring.datasource.username=root
spring.datasource.password=root
#配置数据库连接池的类型
spring.datasource.type=com.alibaba.druid.pool.DruidDataSource
#开启正向工程(根据实体类和映射信息生成数据表) create:创建(会造成已存在的数据丢失) update:创建或更新(推荐)
spring.jpa.hibernate.ddl-auto=update
#是否打印生成sql语句
spring.jpa.show-sql=true
package com.sxt.springdatajpa.dao.UsersRepository
import com.sxt.springdatajpa.pojo.Users;
import org.springframework.data.jpa.repository.JpaRepository;
public interface UsersRepository extends JpaRepository<Users,Integer> {
}
com.sxt.springdatajpa.dao.UsersRepositoryByName
package com.sxt.springdatajpa.dao;
import com.sxt.springdatajpa.pojo.Users;
import org.springframework.data.repository.Repository;
import java.util.List;
/**
*Repository接口的方法名称命名查询
*/
public interface UsersRepositoryByName extends Repository<Users,Integer> {
//方法的名称必须要遵循驼峰式命名规则。findBy(关键字)+属性名称(首字母要大写)+查询条件(首字母大写)
List<Users> findByName(String name); // where name=?
List<Users> findByNameAndAge(String name,Integer age); //where name=? and age=?
List<Users> findByNameLike(String name); // where name like ?
}
SpringdataJpaApplicationTests
@SpringBootTest
class SpringdataJpaApplicationTests {
@Autowired
private UsersRepository usersRepository;
//测试添加用户
@Test
public void testAdd(){
Users users = new Users();
users.setName("张三");
users.setAge(20);
users.setAddress("北京");
usersRepository.save(users);
}
//测试查询所有
@Test
public void testFindAll(){
List<Users> list = usersRepository.findAll();
for(Users user:list){
System.out.println(user);
}
}
//测试根据主键进行查找
@Test
public void testFindById(){
Optional<Users> optional = usersRepository.findById(1);
Users user = optional.get();
System.out.println(user);
}
//测试修改
@Test
public void testUppdate(){
Users users = new Users();
users.setId(1);
users.setName("王五");
users.setAge(30);
users.setAddress("上海");
usersRepository.save(users);//新增和修改都使用save方法，类似与hibernate中的saveOrUpdate方法
}
//测试删除
@Test
public void testDelete(){
usersRepository.deleteById(2);
}
@Test
public void testUserRepository(){
System.out.println(usersRepository);
System.out.println(usersRepository.getClass());
}
}
TestUsersRepositoryByName
package com.sxt.springdatajpa;
import com.sxt.springdatajpa.dao.UsersRepositoryByName;
import com.sxt.springdatajpa.pojo.Users;
import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import java.util.List;
/**
*
//测试Repository接口的命名规则查询
*/
@SpringBootTest
public class TestUsersRepositoryByName {
@Autowired
UsersRepositoryByName usersRepositoryByName;
//测试按照名称进行精确查找
@Test
public void testFindByName(){
List<Users> list = usersRepositoryByName.findByName("王五");
for(Users user:list){
System.out.println(user);
}
}
//测试按照名称和年龄进行精确查找
@Test
public void testFindByNameAndAge(){
List<Users> list = usersRepositoryByName.findByNameAndAge("王五",30);
for(Users user:list){
System.out.println(user);
}
}
//测试按照名称进行模糊查找
@Test
public void testFindByNameLike(){
List<Users> list = usersRepositoryByName.findByNameLike("%王%");
for(Users user:list){
System.out.println(user);
}
}
}
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