目录
一、新增员工
二、文件上传-技术点
1. 文件上传功能
1.客户端上传文件三要素
2 服务端接收文件
Controller接收文件示例
修改允许上传的文件大小
2. 本地存储文件
3. 阿里云OSS存储(这里只写一种,可以用其它的)
1.介绍
2.开通阿里云OSS服务
3.阿里云OSS使用示例
4. 上传员工头像
三、修改员工
1. 查询
2. 修改
四、配置文件
1. SpringBoot的配置文件
1.SpringBoot支持的配置文件格式
2 properties文件
方式1:@Value方式
方式2:@ConfigurationProperties方式
3 yaml文件
yaml基本语法
yaml高级语法
yaml使用示例
读取yaml里的配置参数
2. 阿里云OSS配置的配置与读取
把配置参数提取到yml文件里
修改工具类读取配置参数
一、新增员工
输入员工信息(暂不考虑头像),点击“保存”按钮时,要提交到服务端,把员工信息保存到数据库
分析:
EmpController:
@PostMapping
public Result addEmp(@RequestBody Emp emp){
empService.addEmp(emp);
return Result.success();
}
EmpService:
void addEmp(Emp emp);
EmpServiceImpl:
@Override
public void addEmp(Emp emp) {
emp.setCreateTime(LocalDateTime.now());
emp.setUpdateTime(LocalDateTime.now());
empMapper.insert(emp);
}
EmpMapper:
@Insert("INSERT INTO emp (username, password, name, gender, image, job, entrydate, dept_id, create_time, update_time) " +
"VALUES (#{username}, #{password}, #{name}, #{gender}, #{image}, #{job}, #{entrydate}, #{deptId}, #{createTime}, #{updateTime})")
void insert(Emp emp);
二、文件上传-技术点
1. 文件上传功能
文件上传,是指将本地图片、视频、音频等文件上传到服务器,供其他用户浏览或下载的过程
文件上传在项目中应用非常广泛,我们经常发微博、发微信朋友圈都用到了文件上传功能
1.客户端上传文件三要素
客户端要把文件上传到服务端,需要满足以下三要素,否则仅仅是提交文件名,而不会提交文件内容:
-
使用表单方式提交,且表单提交方式是POST
-
表单的
enctype
属性要设置为multipart/form-data
-
表单里要有文件选择框,且文件选择框必须有name属性:
<input type="file" name="表单参数名">
示例:在工程的resources下的static目录里创建文件demo.html
,内容如下
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>文件上传-示例</title>
</head>
<body>
<!--
1. 使用表单方式提交数据,且表单提交方式为post
2. 表单form标签的enctype属性要设置为multipart/form-data
-->
<form action="/file/upload" method="post" enctype="multipart/form-data">
<input type="text" name="name"><br>
<!-- 3. 表单里要有文件选择框,且必须有name属性 -->
<input type="file" name="avatar"><br>
<button>提交</button>
</form>
</body>
</html>
2 服务端接收文件
在Controller里接收文件数据:
-
需要使用
MultipartFile
类型的参数,MultipartFile
对象的常用方法:-
getOriginalFilename()
:获取原始文件名(客户端上传的文件名称) -
getSize()
:获取文件的大小,单位是byte字节 -
getInputStream()
:获取字节输入流对象,用于获取文件数据 -
transferTo(File dest)
:把文件数据存储到本地磁盘上
-
-
默认允许上传的文件大小为1M,可以通过修改配置文件来调整限制
Controller接收文件示例
服务端接收文件,代码示例:
package com.itheima.controller;
import com.itheima.pojo.Result;
import lombok.extern.slf4j.Slf4j;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.multipart.MultipartFile;
/**
* @author liuyp
* @since 2023/08/21
*/
@Slf4j
@RestController
@RequestMapping("/file")
public class FileController {
/**
* 客户端提交了表单数据,一个是name,一个是avatar
* 在方法上直接加形参,可以接收表单数据:
* name是字符串,使用String类型
* avatar是文件,使用MultipartFile类型
*/
@PostMapping("/upload")
public Result upload(String name, MultipartFile avatar){
return Result.success();
}
}
修改允许上传的文件大小
修改配置文件application.properties或者yaml或yml
#设置:一次请求最大允许提交20MB。默认10MB
spring.servlet.multipart.max-request-size=20MB
#设置:一个文件最大允许10MB。默认1MB
spring.servlet.multipart.max-file-size=10MB
2. 本地存储文件
所谓本地存储文件,是客户端把文件上传到服务器之后,服务器把文件直接存储到自己的磁盘里。
好处:简单
缺点:
-
本地磁盘空间有限,不能存储太多文件;且不方便扩容
-
本地存储文件,没有备份,一旦磁盘出现问题,就会丢失文件
-
维护管理不方便
示例代码:
@Slf4j
@RestController
@RequestMapping("/file")
public class FileController {
@PostMapping("/upload")
public Result upload(String name, MultipartFile avatar) throws IOException {
log.info("name={}", name);
//重命名文件
// 1. 获取原始文件名。比如:100.jpg
String filename = avatar.getOriginalFilename();
// 2. 截取得到后缀名。比如:.jpg
String suffix = filename.substring(filename.lastIndexOf("."));
// 3. 重新生成新的文件名。比如:2ceea81e-2a4d-4709-8332-367ea4e34e23.jpg
filename = UUID.randomUUID().toString() + suffix;
//保存文件到本地磁盘
avatar.transferTo(Paths.get("E:\\" + filename));
log.info("文件已保存到:E:/{}", filename);
return Result.success();
}
}
3. 阿里云OSS存储(这里只写一种,可以用其它的)
1.介绍
阿里云对象存储 OSS(Object Storage Service)是一款海量、安全、低成本、高可靠的云存储服务,提供最高可达 99.995 % 的服务可用性。多种存储类型供选择,全面优化存储成本。
2.开通阿里云OSS服务
(1)打开https://www.aliyun.com/ ,申请阿里云账号并完成实名认证。
(2)充值 (可以不用做)
(3)开通OSS
登录阿里云官网。 点击右上角的控制台。
将鼠标移至产品,找到并单击对象存储OSS,打开OSS产品详情页面。在OSS产品详情页中的单击立即开通。
开通服务后,在OSS产品详情页面单击管理控制台直接进入OSS管理控制台界面。您也可以单击位于官网首页右上方菜单栏的控制台,进入阿里云管理控制台首页,然后单击左侧的对象存储OSS菜单进入OSS管理控制台界面。
(4)创建存储空间
新建Bucket,命名为 hmleadnews ,读写权限为 ==公共读==(不然别人没办法上传)
3. OSS快速入门
(1)创建测试工程,引入依赖
<dependency>
<groupId>com.aliyun.oss</groupId>
<artifactId>aliyun-sdk-oss</artifactId>
<version>3.15.1</version>
</dependency>
(2)新建类和main方法
import org.junit.jupiter.api.Test;
import com.aliyun.oss.ClientException;
import com.aliyun.oss.OSS;
import com.aliyun.oss.OSSClientBuilder;
import com.aliyun.oss.OSSException;
import java.io.FileInputStream;
import java.io.InputStream;
public class AliOssTest {
@Test
public void testOss(){
// Endpoint以华东1(杭州)为例,其它Region请按实际情况填写。
String endpoint = "https://oss-cn-hangzhou.aliyuncs.com";
// 阿里云账号AccessKey拥有所有API的访问权限,风险很高。强烈建议您创建并使用RAM用户进行API访问或日常运维,请登录RAM控制台创建RAM用户。
String accessKeyId = "---------------------";
String accessKeySecret = "-----------------------";
// 填写Bucket名称,例如examplebucket。
String bucketName = "-----------";
// 填写Object完整路径,完整路径中不能包含Bucket名称,例如exampledir/exampleobject.txt。
String objectName = "0001.jpg";
// 填写本地文件的完整路径,例如D:\\localpath\\examplefile.txt。
// 如果未指定本地路径,则默认从示例程序所属项目对应本地路径中上传文件流。
String filePath= "C:\\Users\\Administrator\\Pictures\\Saved Pictures\\10.jpg";
// 创建OSSClient实例。
OSS ossClient = new OSSClientBuilder().build(endpoint, accessKeyId, accessKeySecret);
try {
InputStream inputStream = new FileInputStream(filePath);
// 创建PutObject请求。
ossClient.putObject(bucketName, objectName, inputStream);
} catch (OSSException oe) {
System.out.println("Caught an OSSException, which means your request made it to OSS, "
+ "but was rejected with an error response for some reason.");
System.out.println("Error Message:" + oe.getErrorMessage());
System.out.println("Error Code:" + oe.getErrorCode());
System.out.println("Request ID:" + oe.getRequestId());
System.out.println("Host ID:" + oe.getHostId());
} catch (Exception ce) {
System.out.println("Caught an ClientException, which means the client encountered "
+ "a serious internal problem while trying to communicate with OSS, "
+ "such as not being able to access the network.");
System.out.println("Error Message:" + ce.getMessage());
} finally {
if (ossClient != null) {
ossClient.shutdown();
}
}
}
}
4. 获取AccessKeyId
3.阿里云OSS使用示例
阿里云OSS文档:OSS Java SDK 兼容性和示例代码_对象存储(OSS)-阿里云帮助中心
阿里云SDK介绍:安装OSS Java SDK_对象存储(OSS)-阿里云帮助中心
上传文件示例代码:如何使用JavaSDK简单上传文件_对象存储(OSS)-阿里云帮助中心
4. 上传员工头像
-
在类上添加
@Component
-
修改配置参数endpoind、accessKeyId、accessKeySecret、bucket名称等,改成自己的
如果要上传文件时:
-
只要使用
@Autowired
注入AliOSSUtils对象,调用它的upload方法就可以了
工具类:
package com.itheima.util;
import com.aliyun.oss.OSS;
import com.aliyun.oss.OSSClientBuilder;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Component;
import org.springframework.web.multipart.MultipartFile;
import java.io.*;
import java.util.UUID;
/**
* 阿里云 OSS 工具类
*/
@Component
public class AliOSSUtils {
@Value("${aliyun.endpoint}")
private String endpoint;
@Value("${aliyun.accessKeyId}")
private String accessKeyId;
@Value("${aliyun.accessKeySecret}")
private String accessKeySecret;
@Value("${aliyun.bucketName}")
private String bucketName;
/**
* 实现上传图片到OSS
*/
public String upload(MultipartFile file) throws IOException {
// 获取上传的文件的输入流
InputStream inputStream = file.getInputStream();
// 避免文件覆盖
String originalFilename = file.getOriginalFilename();
String fileName = UUID.randomUUID().toString() + originalFilename.substring(originalFilename.lastIndexOf("."));
//上传文件到 OSS
OSS ossClient = new OSSClientBuilder().build(endpoint, accessKeyId, accessKeySecret);
ossClient.putObject(bucketName, fileName, inputStream);
//文件访问路径
String url = endpoint.split("//")[0] + "//" + bucketName + "." + endpoint.split("//")[1] + "/" + fileName;
// 关闭ossClient
ossClient.shutdown();
return url;// 把上传到oss的路径返回
}
}
controller:
package com.itheima.controller;
import com.itheima.pojo.Result;
import com.itheima.util.AliOSSUtils;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.multipart.MultipartFile;
import java.io.IOException;
@Slf4j
@RestController
public class UploadController {
@Autowired
private AliOSSUtils ossUtils;
@PostMapping("/upload")
public Result upload(MultipartFile image) throws IOException {
String url = ossUtils.upload(image);
return Result.success(url);
}
}
三、修改员工
1. 查询
EmpController:
@GetMapping("/{id}")
public Result queryEmpById(@PathVariable("id") Integer id){
Emp emp = empService.queryEmpById(id);
return Result.success(emp);
}
EmpService:
Emp queryEmpById(Integer id);
EmpServiceImpl:
@Override
public Emp queryEmpById(Integer id) {
return empMapper.selectById(id);
}
EmpMapper:
@Select("select * from emp where id = #{id}")
Emp selectById(Integer id);
2. 修改
EmpController:
@PutMapping
public Result updateEmp(@RequestBody Emp emp){
empService.updateEmpById(emp);
return Result.success();
}
EmpService:
void updateEmpById(Emp emp);
EmpServiceImpl:
@Override
public void updateEmpById(Emp emp) {
empMapper.updateById(emp);
}
EmpMapper:
void updateById(Emp emp);
EmpMapper.xml:
<update id="updateById">
UPDATE emp
<set>
<if test="username!=null and username.length()>0">username = #{username},</if>
<if test="password!=null and password.length()>0">password = #{password},</if>
<if test="name!=null and name.length()>0">name = #{name},</if>
<if test="gender!=null">gender = #{gender},</if>
<if test="image!=null and image.length()>0">image = #{image},</if>
<if test="job!=null">job = #{job},</if>
<if test="entrydate!=null">entrydate = #{entrydate},</if>
<if test="deptId!=null">dept_id = #{deptId},</if>
<if test="updateTime!=null">update_time = #{updateTime}</if>
</set>
WHERE id = #{id};
</update>
四、配置文件
1. SpringBoot的配置文件
1.SpringBoot支持的配置文件格式
SpringBoot工程支持的配置文件格式有:
-
application.properties
优点:格式简单,
key=value
,所有配置参数都是平级的关系缺点:不方便表示不同层级的配置参数
-
application.yml
或者application.yaml
优点:格式简单,
key: value
,还能表示配置参数之间的层级
无论是哪种配置文件,都可以用于配置参数。包括SpringBoot本身的参数,或者是自定义的参数。而SpringBoot工程会自动读取配置文件,我们可以直接获取配置文件里的参数值
2 properties文件
使用properties配置参数
<span style="background-color:#f8f8f8"><span style="color:#333333"><span style="color:#0000ff">aliyun.endpoint</span>=<span style="color:#009900">https</span>:<span style="color:#009900">//oss-cn-beijing.aliyuncs.com</span>
<span style="color:#0000ff">aliyun.accessKeyId</span>=<span style="color:#009900">LTAI5tG3TbA9HLs22KEtimyB</span>
<span style="color:#0000ff">aliyun.accessKeySecret</span>=<span style="color:#009900">4avUxhaO5KCTl5pqpta3AdU98mT9um</span>
<span style="color:#0000ff">aliyun.bucketName</span>=<span style="color:#009900">itheima-liuyp</span></span></span>
获取参数值
无论是在application.properties里,还是在application.yaml里配置了参数,如果我们的程序代码中需要获取这些参数该怎么做呢?
-
首先:并不需要我们加载配置文件,SpringBoot会帮我们加载配置文件,把所有配置参数存储起来
-
然后:我们需要什么参数,直接使用注解注入参数值即可。常用两种方式
@Value方式
@ConfigurationProperties方式
方式1:@Value
方式
作用:在==任意bean对象==里,都可以使用@Value
,注入某个参数值
用法:在bean对象里增加成员变量,在成员变量上增加注解@Value("${参数名}")
使用:如果只需要获取少量几个参数值,就使用@Value("${参数名}")
;如果要读取大量参数,建议使用方式2
<span style="background-color:#f8f8f8"><span style="color:#333333"><span style="color:#770088">package</span> <span style="color:#0000ff">com</span>.<span style="color:#000000">itheima</span>.<span style="color:#000000">controller</span>;
<span style="color:#770088">import</span> <span style="color:#000000">com</span>.<span style="color:#000000">itheima</span>.<span style="color:#000000">pojo</span>.<span style="color:#000000">Result</span>;
<span style="color:#770088">import</span> <span style="color:#000000">com</span>.<span style="color:#000000">itheima</span>.<span style="color:#000000">service</span>.<span style="color:#000000">EmpService</span>;
<span style="color:#770088">import</span> <span style="color:#000000">org</span>.<span style="color:#000000">springframework</span>.<span style="color:#000000">beans</span>.<span style="color:#000000">factory</span>.<span style="color:#000000">annotation</span>.<span style="color:#000000">Autowired</span>;
<span style="color:#770088">import</span> <span style="color:#000000">org</span>.<span style="color:#000000">springframework</span>.<span style="color:#000000">beans</span>.<span style="color:#000000">factory</span>.<span style="color:#000000">annotation</span>.<span style="color:#000000">Value</span>;
<span style="color:#770088">import</span> <span style="color:#000000">org</span>.<span style="color:#000000">springframework</span>.<span style="color:#000000">web</span>.<span style="color:#000000">bind</span>.<span style="color:#000000">annotation</span>.<span style="color:#000000">GetMapping</span>;
<span style="color:#770088">import</span> <span style="color:#000000">org</span>.<span style="color:#000000">springframework</span>.<span style="color:#000000">web</span>.<span style="color:#000000">bind</span>.<span style="color:#000000">annotation</span>.<span style="color:#000000">RestController</span>;
<span style="color:#aa5500">/**</span>
<span style="color:#aa5500">* @author liuyp</span>
<span style="color:#aa5500">* @since 2023/08/22</span>
<span style="color:#aa5500">*/</span>
<span style="color:#555555">@RestController</span>
<span style="color:#770088">public</span> <span style="color:#770088">class</span> <span style="color:#0000ff">DemoConfigController</span> {
<span style="color:#aa5500">/** 把“AA”直接注入赋值给变量aa */</span>
<span style="color:#555555">@Value</span>(<span style="color:#aa1111">"AA"</span>)
<span style="color:#770088">private</span> <span style="color:#008855">String</span> <span style="color:#000000">aa</span>;
<span style="color:#aa5500">/** 取名称为“aliyun.endpoint”的参数值,注入赋值给当前成员变量endpoint */</span>
<span style="color:#555555">@Value</span>(<span style="color:#aa1111">"${aliyun.endpoint}"</span>)
<span style="color:#770088">private</span> <span style="color:#008855">String</span> <span style="color:#000000">endpoint</span>;
<span style="color:#aa5500">/**取名称为“aliyun.accessKeyId”的参数值,注入赋值给当前成员变量*/</span>
<span style="color:#555555">@Value</span>(<span style="color:#aa1111">"${aliyun.accessKeyId}"</span>)
<span style="color:#770088">private</span> <span style="color:#008855">String</span> <span style="color:#000000">accessKey</span>;
<span style="color:#555555">@GetMapping</span>(<span style="color:#aa1111">"/config1"</span>)
<span style="color:#770088">public</span> <span style="color:#000000">Result</span> <span style="color:#000000">config1</span>(){
<span style="color:#770088">return</span> <span style="color:#000000">Result</span>.<span style="color:#000000">success</span>(<span style="color:#000000">accessKey</span>);
}
}</span></span>
方式2:@ConfigurationProperties
方式
作用:读取一批配置参数,封装到一个JavaBean对象里。当需要使用参数值的时候,只要得到这个JavaBean对象即可
用法:
-
准备一个JavaBean类,用于封装一批参数值
类上加@ConfigurationProperties + @Component
-
使用时用@Autowired注入这个JavaBean对象
优点:可以一次性读取一批配置参数值,使用时让代码更简洁
示例:
<span style="background-color:#f8f8f8"><span style="color:#333333"><span style="color:#770088">package</span> <span style="color:#0000ff">com</span>.<span style="color:#000000">itheima</span>.<span style="color:#000000">pojo</span>;
<span style="color:#770088">import</span> <span style="color:#000000">lombok</span>.<span style="color:#000000">Data</span>;
<span style="color:#770088">import</span> <span style="color:#000000">org</span>.<span style="color:#000000">springframework</span>.<span style="color:#000000">boot</span>.<span style="color:#000000">context</span>.<span style="color:#000000">properties</span>.<span style="color:#000000">ConfigurationProperties</span>;
<span style="color:#770088">import</span> <span style="color:#000000">org</span>.<span style="color:#000000">springframework</span>.<span style="color:#000000">stereotype</span>.<span style="color:#000000">Component</span>;
<span style="color:#aa5500">/**</span>
<span style="color:#aa5500">* 1. 类里要有private成员变量,@Data提供get和set方法</span>
<span style="color:#aa5500">* 2. 类上要加@ConfigurationProperties(prefix="配置参数名的前缀")</span>
<span style="color:#aa5500">* prefix + 成员变量名:要对应一个配置参数名</span>
<span style="color:#aa5500">* 3. 类上加@Component,让Spring帮我们生成类的对象放到容器里</span>
<span style="color:#aa5500">* @author liuyp</span>
<span style="color:#aa5500">* @since 2023/08/22</span>
<span style="color:#aa5500">*/</span>
<span style="color:#555555">@Data</span>
<span style="color:#555555">@Component</span>
<span style="color:#555555">@ConfigurationProperties</span>(<span style="color:#000000">prefix</span> <span style="color:#981a1a">=</span> <span style="color:#aa1111">"aliyun"</span>)
<span style="color:#770088">public</span> <span style="color:#770088">class</span> <span style="color:#0000ff">AliyunProperties</span> {
<span style="color:#770088">private</span> <span style="color:#008855">String</span> <span style="color:#000000">endpoint</span>;
<span style="color:#770088">private</span> <span style="color:#008855">String</span> <span style="color:#000000">accessKeyId</span>;
<span style="color:#770088">private</span> <span style="color:#008855">String</span> <span style="color:#000000">accessKeySecret</span>;
<span style="color:#770088">private</span> <span style="color:#008855">String</span> <span style="color:#000000">bucketName</span>;
}</span></span>
使用时:
<span style="background-color:#f8f8f8"><span style="color:#333333"><span style="color:#770088">package</span> <span style="color:#0000ff">com</span>.<span style="color:#000000">itheima</span>.<span style="color:#000000">controller</span>;
<span style="color:#770088">import</span> <span style="color:#000000">com</span>.<span style="color:#000000">itheima</span>.<span style="color:#000000">pojo</span>.<span style="color:#000000">AliyunProperties</span>;
<span style="color:#770088">import</span> <span style="color:#000000">com</span>.<span style="color:#000000">itheima</span>.<span style="color:#000000">pojo</span>.<span style="color:#000000">Result</span>;
<span style="color:#770088">import</span> <span style="color:#000000">com</span>.<span style="color:#000000">itheima</span>.<span style="color:#000000">service</span>.<span style="color:#000000">EmpService</span>;
<span style="color:#770088">import</span> <span style="color:#000000">org</span>.<span style="color:#000000">springframework</span>.<span style="color:#000000">beans</span>.<span style="color:#000000">factory</span>.<span style="color:#000000">annotation</span>.<span style="color:#000000">Autowired</span>;
<span style="color:#770088">import</span> <span style="color:#000000">org</span>.<span style="color:#000000">springframework</span>.<span style="color:#000000">beans</span>.<span style="color:#000000">factory</span>.<span style="color:#000000">annotation</span>.<span style="color:#000000">Value</span>;
<span style="color:#770088">import</span> <span style="color:#000000">org</span>.<span style="color:#000000">springframework</span>.<span style="color:#000000">web</span>.<span style="color:#000000">bind</span>.<span style="color:#000000">annotation</span>.<span style="color:#000000">GetMapping</span>;
<span style="color:#770088">import</span> <span style="color:#000000">org</span>.<span style="color:#000000">springframework</span>.<span style="color:#000000">web</span>.<span style="color:#000000">bind</span>.<span style="color:#000000">annotation</span>.<span style="color:#000000">RestController</span>;
<span style="color:#aa5500">/**</span>
<span style="color:#aa5500">* @author liuyp</span>
<span style="color:#aa5500">* @since 2023/08/22</span>
<span style="color:#aa5500">*/</span>
<span style="color:#555555">@RestController</span>
<span style="color:#770088">public</span> <span style="color:#770088">class</span> <span style="color:#0000ff">DemoConfigController</span> {
<span style="color:#555555">@Autowired</span>
<span style="color:#770088">private</span> <span style="color:#000000">AliyunProperties</span> <span style="color:#000000">aliyunProperties</span>;
<span style="color:#555555">@GetMapping</span>(<span style="color:#aa1111">"/config1"</span>)
<span style="color:#770088">public</span> <span style="color:#000000">Result</span> <span style="color:#000000">config1</span>(){
<span style="color:#770088">return</span> <span style="color:#000000">Result</span>.<span style="color:#000000">success</span>(<span style="color:#000000">aliyunProperties</span>);
}
}</span></span>
3 yaml文件
YAML(/ˈjæməl/
,尾音类似camel骆驼) 是 "YAML Ain't a Markup Language"(YAML 不是一种标记语言)的递归缩写。它是一个可读性高,用来表达数据序列化的格式。
YAML可以简单表达清单、散列表,标量等数据形态。它使用空白符号缩进和大量依赖外观的特色,特别适合用来表达或编辑数据结构、各种配置文件、倾印调试内容、文件大纲。
YAML 的配置文件后缀为 .yml
或者.yaml
yaml基本语法
-
使用key和value配置参数值,key和value之间要有
:空格
进行分隔。如果使用:
分隔,是语法错误 -
相同层级的key-value,前边要有相同数量的空格。几个空格无所谓,但是必须有相同数量的空格
yaml高级语法
yaml的高级语法,可以让我们配置数组或集合、Map结构的数据,语法如下:
-
纯量:不可再拆分的基本值。包括:字符串,布尔,整数,浮点数,null,时间,日期
-
数组:以
-空格
开头再跟上值,表示数组里的一个元素 -
对象:使用
key: value
格式形式,注意冒号后边有一个空格
yaml使用示例
<span style="background-color:#f8f8f8"><span style="color:#333333"><span style="color:#221199">username</span><span style="color:#555555">: </span>zhangsan
<span style="color:#221199">user</span><span style="color:#555555">:</span>
<span style="color:#221199"> name</span><span style="color:#555555">: </span>张三 <span style="color:#aa5500">#相当于properties里user.name=张三</span>
<span style="color:#221199"> gender</span><span style="color:#555555">: </span>男 <span style="color:#aa5500">#相当于properties里user.gender=男</span>
<span style="color:#221199"> age</span><span style="color:#555555">: </span>20 <span style="color:#aa5500">#相当于properties里user.age=20</span>
<span style="color:#221199"> girls</span><span style="color:#555555">: </span><span style="color:#aa5500">#girls是一个集合或数组,集合里现在有3个元素值</span>
<span style="color:#555555"> - </span>小丽
<span style="color:#555555"> - </span>小美
<span style="color:#555555"> - </span>小坤
<span style="color:#221199"> info</span><span style="color:#555555">:</span>
<span style="color:#221199"> email</span><span style="color:#555555">: </span>zhangsan@163.com
<span style="color:#221199"> phone</span><span style="color:#555555">: </span><span style="color:#116644">13800138000</span></span></span>
读取yaml里的配置参数
和刚刚读取properties文件里的参数,是完全相同的
-
@Value("${参数名}")
,读取某一个参数 -
@ConfigurationPropperties
把一批参数封装成一个JavaBean对象
2. 阿里云OSS配置的配置与读取
把配置参数提取到yml文件里
<span style="background-color:#f8f8f8"><span style="color:#333333"><span style="color:#221199">aliyun</span><span style="color:#555555">:</span>
<span style="color:#221199"> endpoint</span><span style="color:#555555">: </span>https<span style="color:#555555">:</span>//oss-cn-beijing.aliyuncs.com
<span style="color:#221199"> accessKeyId</span><span style="color:#555555">: </span>LTAI5tG3TbA9HLs22KEtimyB
<span style="color:#221199"> accessKeySecret</span><span style="color:#555555">: </span>4avUxhaO5KCTl5pqpta3AdU98mT9um
<span style="color:#221199"> bucketName</span><span style="color:#555555">: </span>itheima-liuyp</span></span>
修改工具类读取配置参数
<span style="background-color:#f8f8f8"><span style="color:#333333"><span style="color:#770088">package</span> <span style="color:#0000ff">com</span>.<span style="color:#000000">itheima</span>.<span style="color:#000000">util</span>;
<span style="color:#770088">import</span> <span style="color:#000000">com</span>.<span style="color:#000000">aliyun</span>.<span style="color:#000000">oss</span>.<span style="color:#000000">OSS</span>;
<span style="color:#770088">import</span> <span style="color:#000000">com</span>.<span style="color:#000000">aliyun</span>.<span style="color:#000000">oss</span>.<span style="color:#000000">OSSClientBuilder</span>;
<span style="color:#770088">import</span> <span style="color:#000000">org</span>.<span style="color:#000000">springframework</span>.<span style="color:#000000">beans</span>.<span style="color:#000000">factory</span>.<span style="color:#000000">annotation</span>.<span style="color:#000000">Value</span>;
<span style="color:#770088">import</span> <span style="color:#000000">org</span>.<span style="color:#000000">springframework</span>.<span style="color:#000000">stereotype</span>.<span style="color:#000000">Component</span>;
<span style="color:#770088">import</span> <span style="color:#000000">org</span>.<span style="color:#000000">springframework</span>.<span style="color:#000000">web</span>.<span style="color:#000000">multipart</span>.<span style="color:#000000">MultipartFile</span>;
<span style="color:#770088">import</span> <span style="color:#000000">java</span>.<span style="color:#000000">io</span>.<span style="color:#981a1a">*</span>;
<span style="color:#770088">import</span> <span style="color:#000000">java</span>.<span style="color:#000000">util</span>.<span style="color:#000000">UUID</span>;
<span style="color:#aa5500">/**</span>
<span style="color:#aa5500">* 阿里云 OSS 工具类</span>
<span style="color:#aa5500">*/</span>
<span style="color:#555555">@Component</span>
<span style="color:#770088">public</span> <span style="color:#770088">class</span> <span style="color:#0000ff">AliOSSUtils</span> {
<span style="color:#555555">@Value</span>(<span style="color:#aa1111">"${aliyun.endpoint}"</span>)
<span style="color:#770088">private</span> <span style="color:#008855">String</span> <span style="color:#000000">endpoint</span>;
<span style="color:#555555">@Value</span>(<span style="color:#aa1111">"${aliyun.accessKeyId}"</span>)
<span style="color:#770088">private</span> <span style="color:#008855">String</span> <span style="color:#000000">accessKeyId</span>;
<span style="color:#555555">@Value</span>(<span style="color:#aa1111">"${aliyun.accessKeySecret}"</span>)
<span style="color:#770088">private</span> <span style="color:#008855">String</span> <span style="color:#000000">accessKeySecret</span>;
<span style="color:#555555">@Value</span>(<span style="color:#aa1111">"${aliyun.bucketName}"</span>)
<span style="color:#770088">private</span> <span style="color:#008855">String</span> <span style="color:#000000">bucketName</span>;
<span style="color:#aa5500">/**</span>
<span style="color:#aa5500">* 实现上传图片到OSS</span>
<span style="color:#aa5500">*/</span>
<span style="color:#770088">public</span> <span style="color:#008855">String</span> <span style="color:#000000">upload</span>(<span style="color:#000000">MultipartFile</span> <span style="color:#000000">file</span>) <span style="color:#770088">throws</span> <span style="color:#000000">IOException</span> {
<span style="color:#aa5500">// 获取上传的文件的输入流</span>
<span style="color:#000000">InputStream</span> <span style="color:#000000">inputStream</span> <span style="color:#981a1a">=</span> <span style="color:#000000">file</span>.<span style="color:#000000">getInputStream</span>();
<span style="color:#aa5500">// 避免文件覆盖</span>
<span style="color:#008855">String</span> <span style="color:#000000">originalFilename</span> <span style="color:#981a1a">=</span> <span style="color:#000000">file</span>.<span style="color:#000000">getOriginalFilename</span>();
<span style="color:#008855">String</span> <span style="color:#000000">fileName</span> <span style="color:#981a1a">=</span> <span style="color:#000000">UUID</span>.<span style="color:#000000">randomUUID</span>().<span style="color:#000000">toString</span>() <span style="color:#981a1a">+</span> <span style="color:#000000">originalFilename</span>.<span style="color:#000000">substring</span>(<span style="color:#000000">originalFilename</span>.<span style="color:#000000">lastIndexOf</span>(<span style="color:#aa1111">"."</span>));
<span style="color:#aa5500">//上传文件到 OSS</span>
<span style="color:#000000">OSS</span> <span style="color:#000000">ossClient</span> <span style="color:#981a1a">=</span> <span style="color:#770088">new</span> <span style="color:#000000">OSSClientBuilder</span>().<span style="color:#000000">build</span>(<span style="color:#000000">endpoint</span>, <span style="color:#000000">accessKeyId</span>, <span style="color:#000000">accessKeySecret</span>);
<span style="color:#000000">ossClient</span>.<span style="color:#000000">putObject</span>(<span style="color:#000000">bucketName</span>, <span style="color:#000000">fileName</span>, <span style="color:#000000">inputStream</span>);
<span style="color:#aa5500">//文件访问路径</span>
<span style="color:#008855">String</span> <span style="color:#000000">url</span> <span style="color:#981a1a">=</span> <span style="color:#000000">endpoint</span>.<span style="color:#000000">split</span>(<span style="color:#aa1111">"//"</span>)[<span style="color:#116644">0</span>] <span style="color:#981a1a">+</span> <span style="color:#aa1111">"//"</span> <span style="color:#981a1a">+</span> <span style="color:#000000">bucketName</span> <span style="color:#981a1a">+</span> <span style="color:#aa1111">"."</span> <span style="color:#981a1a">+</span> <span style="color:#000000">endpoint</span>.<span style="color:#000000">split</span>(<span style="color:#aa1111">"//"</span>)[<span style="color:#116644">1</span>] <span style="color:#981a1a">+</span> <span style="color:#aa1111">"/"</span> <span style="color:#981a1a">+</span> <span style="color:#000000">fileName</span>;
<span style="color:#aa5500">// 关闭ossClient</span>
<span style="color:#000000">ossClient</span>.<span style="color:#000000">shutdown</span>();
<span style="color:#770088">return</span> <span style="color:#000000">url</span>;<span style="color:#aa5500">// 把上传到oss的路径返回</span>
}
}</span></span>