提示：昨天不是写了一个类似与图片添加水印的版本吗,今天来写一个带数据库，并且可以完整访问的版本
文章目录
目录
文章目录
引入库
配置文件
数据库配置
字段配置
索引配置
数据库表语句
启动文件
前端代码
整体代码目录
配置类AppConfig
Controller层
ABaseController
AGlobalExceptionHandlerController
TestController
Constants
dto
enums
DateTimePatternEnum
FileStatusEnum
FileTypeEnum
ResponseCodeEnum
VO
FileInfoVo
ResponseVO
异常处理器
Mappers
FileInfoMapper
FileInfoMapper.xml
Service
UploadService
UploadServiceImpl
工具类
FileUtils
StringUtil
效果
不带水印访问
带水印访问
总结
引入库
<dependencies><!-- 引入Thymeleaf模板引擎的starter，用于前端页面的渲染 --><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-thymeleaf</artifactId></dependency><!-- 引入Web starter，包含Spring Web MVC等，用于构建Web应用 --><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-web</artifactId></dependency><!-- 引入MyBatis与Spring Boot的集成starter，简化MyBatis的配置与使用 --><dependency><groupId>org.mybatis.spring.boot</groupId><artifactId>mybatis-spring-boot-starter</artifactId><version>2.2.0</version></dependency><!-- 引入MySQL驱动，用于数据库连接 --><dependency><groupId>com.mysql</groupId><artifactId>mysql-connector-j</artifactId><scope>runtime</scope></dependency><!-- 引入Lombok，提供注解方式简化JavaBean的创建与维护，设置为optional，非必须依赖 --><dependency><groupId>org.projectlombok</groupId><artifactId>lombok</artifactId><optional>true</optional></dependency><!-- 引入Spring Boot的测试starter，包含测试相关依赖，用于单元测试和集成测试 --><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-test</artifactId><scope>test</scope></dependency><!-- 引入Commons IO，提供文件操作相关的工具类 --><dependency><groupId>commons-io</groupId><artifactId>commons-io</artifactId><version>2.11.0</version></dependency><!-- 引入thumbnailator，用于图片缩放、裁剪等操作 --><dependency><groupId>net.coobird</groupId><artifactId>thumbnailator</artifactId><version>0.4.8</version></dependency><!-- 引入Apache Commons Lang，提供一些Java语言工具类 --><dependency><groupId>org.apache.commons</groupId><artifactId>commons-lang3</artifactId><version>3.12.0</version></dependency></dependencies>配置文件
java"># 应用服务 WEB 访问端口
server.port=8080
# 路径前缀
server.servlet.context-path=/api # 项目目录
project.folder=文件存放的路径# 数据库配置spring.datasource.url=jdbc:mysql://127.0.0.1:3306/shuiyin?serverTimezone=GMT%2B8&useUnicode=true&characterEncoding=utf8&autoReconnect=true&allowMultiQueries=true
spring.datasource.username=root
spring.datasource.password=root
spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver
spring.datasource.hikari.pool-name=HikariCPDatasource
spring.datasource.hikari.minimum-idle=5
spring.datasource.hikari.idle-timeout=180000
spring.datasource.hikari.maximum-pool-size=10
spring.datasource.hikari.auto-commit=true
spring.datasource.hikari.max-lifetime=1800000
spring.datasource.hikari.connection-timeout=30000
spring.datasource.hikari.connection-test-query=SELECT 1
数据库配置
字段配置
索引配置
数据库表语句
CREATE TABLE `file_info` (`file_id` varchar(15) COLLATE utf8mb4_general_ci NOT NULL COMMENT '文件id',`file_name` varchar(150) COLLATE utf8mb4_general_ci DEFAULT NULL COMMENT '文件名字',`file_type` tinyint(1) DEFAULT NULL COMMENT '文件类型 0:png 1:jpg 2:jpeg 3:webp 4:gif',`file_size` bigint DEFAULT NULL COMMENT '文件大小',`file_path` varchar(255) COLLATE utf8mb4_general_ci DEFAULT NULL COMMENT '文件路径',`file_md5` varchar(32) COLLATE utf8mb4_general_ci DEFAULT NULL COMMENT '文件md5',`status` tinyint(1) DEFAULT NULL COMMENT '状态 0:禁用 1:启用',`create_time` datetime DEFAULT NULL COMMENT '创建时间',PRIMARY KEY (`file_id`),UNIQUE KEY `idx_file_id` (`file_id`) USING BTREE,UNIQUE KEY `idx_file_name` (`file_name`) USING BTREE,UNIQUE KEY `idx_file_md5` (`file_md5`) USING BTREE
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_general_ci;启动文件
java">@SpringBootApplication
@MapperScan("com.hhh.mappers")
@EnableTransactionManagement
public class MysApplication {public static void main(String[] args) {SpringApplication.run(MysApplication.class, args);}}前端代码
<!DOCTYPE html>
<html lang="en">
<head><meta charset="UTF-8"><title>upload</title>
</head>
<body>
<h1>上传图片</h1>
<form method="post" enctype="multipart/form-data" action="http://localhost:8080/api/upload"><input type="file" name="file" /><button type="submit">上传</button>
</form>
</body>
</html>整体代码目录
配置类AppConfig
这段代码主要是为了获取项目目录的
java">
@Component
public class AppConfig {@Value("${project.folder:}")private String projectFolder;public String getProjectFolder() {return projectFolder;}
}Controller层
ABaseController
基础控制器类，提供通用的响应构建方法
java">/*** 基础控制器类，提供通用的响应构建方法。*/
public class ABaseController {/*** 表示操作成功的状态码。*/protected static final String STATUC_SUCCESS = "success";/*** 表示操作失败或出现错误的状态码。*/protected static final String STATUC_ERROR = "error";/*** 日志记录器，用于记录控制器类的运行时日志。*/protected static final Logger logger = LoggerFactory.getLogger(ABaseController.class);/*** 构建一个表示操作成功的响应。** @param t 返回的数据对象。* @param <T> 数据对象的类型。* @return 带有成功状态的响应对象。*/protected <T> ResponseVO getSuccessResponseVO(T t) {ResponseVO<T> responseVO = new ResponseVO<>();responseVO.setStatus(STATUC_SUCCESS);responseVO.setCode(ResponseCodeEnum.CODE_200.getCode());responseVO.setInfo(ResponseCodeEnum.CODE_200.getMsg());responseVO.setData(t);return responseVO;}/*** 构建一个表示业务错误的响应。** @param e 业务异常对象，包含错误代码和错误信息。* @param t 返回的数据对象。* @param <T> 数据对象的类型。* @return 带有业务错误状态的响应对象。*/protected <T> ResponseVO getBusinessErrorResponseVO(BusinessException e, T t) {ResponseVO vo = new ResponseVO();vo.setStatus(STATUC_ERROR);if (e.getCode() == null) {vo.setCode(ResponseCodeEnum.CODE_600.getCode());} else {vo.setCode(e.getCode());}vo.setInfo(e.getMessage());vo.setData(t);return vo;}/*** 构建一个表示服务器错误的响应。** @param t 返回的数据对象。* @param <T> 数据对象的类型。* @return 带有服务器错误状态的响应对象。*/protected <T> ResponseVO getServerErrorResponseVO(T t) {ResponseVO vo = new ResponseVO();vo.setStatus(STATUC_ERROR);vo.setCode(ResponseCodeEnum.CODE_500.getCode());vo.setInfo(ResponseCodeEnum.CODE_500.getMsg());vo.setData(t);return vo;}}AGlobalExceptionHandlerController
全局异常处理控制器，继承自ABaseController，用于处理应用程序抛出的异常。
java">/*** 全局异常处理控制器，继承自ABaseController，用于处理应用程序抛出的异常。* 使用@RestControllerAdvice注解标识这是一个全局异常处理类。*/
@RestControllerAdvice
public class AGlobalExceptionHandlerController extends ABaseController {private static final Logger logger = LoggerFactory.getLogger(AGlobalExceptionHandlerController.class);/*** 处理所有类型的异常。* @param e 抛出的异常对象。* @param request HTTP请求对象，用于获取请求URL。* @return 返回一个封装了异常信息的ResponseVO对象。*/@ExceptionHandler(value = Exception.class)Object handleException(Exception e, HttpServletRequest request) {// 记录异常信息到日志logger.error("请求错误，请求地址{},错误信息:", request.getRequestURL(), e);ResponseVO ajaxResponse = new ResponseVO();// 根据不同的异常类型设置响应码和信息// 404 - 请求未找到if (e instanceof NoHandlerFoundException) {ajaxResponse.setCode(ResponseCodeEnum.CODE_404.getCode());ajaxResponse.setInfo(ResponseCodeEnum.CODE_404.getMsg());ajaxResponse.setStatus(STATUC_ERROR);} else if (e instanceof BusinessException) {// 业务异常// 业务错误BusinessException biz = (BusinessException) e;ajaxResponse.setCode(biz.getCode() == null ? ResponseCodeEnum.CODE_600.getCode() : biz.getCode());ajaxResponse.setInfo(biz.getMessage());ajaxResponse.setStatus(STATUC_ERROR);} else if (e instanceof BindException || e instanceof MethodArgumentTypeMismatchException) {// 参数绑定异常或参数类型不匹配异常// 参数类型错误ajaxResponse.setCode(ResponseCodeEnum.CODE_600.getCode());ajaxResponse.setInfo(ResponseCodeEnum.CODE_600.getMsg());ajaxResponse.setStatus(STATUC_ERROR);} else if (e instanceof DuplicateKeyException) {// 数据库主键重复异常// 主键冲突ajaxResponse.setCode(ResponseCodeEnum.CODE_601.getCode());ajaxResponse.setInfo(ResponseCodeEnum.CODE_601.getMsg());ajaxResponse.setStatus(STATUC_ERROR);} else {// 其他未指定的异常ajaxResponse.setCode(ResponseCodeEnum.CODE_500.getCode());ajaxResponse.setInfo(ResponseCodeEnum.CODE_500.getMsg());ajaxResponse.setStatus(STATUC_ERROR);}return ajaxResponse;}
}TestController
主体控制器类
java">@RestController
public class TestController extends ABaseController {@Resourceprivate UploadService uploadService;@Resourceprivate AppConfig appConfig;@RequestMapping("/upload")public ResponseVO upload(@RequestParam("file")MultipartFile file) throws IOException, NoSuchAlgorithmException {if(null == file){throw new BusinessException("上传文件不能为空");}FileInfoVo fileinfoVo = uploadService.upload(file);return getSuccessResponseVO(fileinfoVo);}/*** 获取不带水印版本的图片* @param fileId* @param response*/@RequestMapping("/getFileInfo/{fileId}")public void getFileInfo(@PathVariable("fileId") String fileId, HttpServletResponse response){FileInfoVo fileInfo = uploadService.getFileInfo(fileId);response.setContentType("image/jpg");String filePath = fileInfo.getFilePath();FileUtils.readFile(response, appConfig.getProjectFolder()+filePath);}/*** 获取带水印版本的图片* @param fileId* @param response*/@RequestMapping("/getWatermarkFileInfo/{fileId}")public void getWatermarkFileInfo(@PathVariable("fileId") String fileId, HttpServletResponse response){FileInfoVo fileInfo = uploadService.getFileInfo(fileId);response.setContentType("image/jpg");String filePath = fileInfo.getFilePath();System.out.println(filePath);int dotIndex = filePath.lastIndexOf(".");if(dotIndex != -1){filePath = filePath.substring(0,dotIndex)+"_."+filePath.substring(dotIndex+1);}FileUtils.readFile(response, appConfig.getProjectFolder()+filePath);}
}
Constants
常量代码
java">/*** Constants类用于定义应用程序中使用的常量。* 该类中的常量应该是整个应用程序范围内不变的值。*/
public class Constants {/*** 文件路径常量。* 该常量定义了访问文件系统的根路径。* 使用此常量可以确保应用程序中对文件路径的引用具有一致性和可维护性。*/public static final String FILE_PATH = "/file";
}
dto
文件信息类
java">package com.hhh.entity.dto;import com.fasterxml.jackson.annotation.JsonFormat;
import org.springframework.format.annotation.DateTimeFormat;import java.util.Date;public class FileInfoDto {private String fileId;private String fileName;private Integer fileType;private Long fileSize;private String filePath;private String fileMd5;private Integer status;@JsonFormat(pattern = "yyyy-MM-dd HH:mm:ss", timezone = "GMT+8")@DateTimeFormat(pattern = "yyyy-MM-dd HH:mm:ss")private Date createTime;public String getFileId() {return fileId;}public void setFileId(String fileId) {this.fileId = fileId;}public String getFileName() {return fileName;}public void setFileName(String fileName) {this.fileName = fileName;}public Integer getFileType() {return fileType;}public void setFileType(Integer fileType) {this.fileType = fileType;}public Long getFileSize() {return fileSize;}public void setFileSize(Long fileSize) {this.fileSize = fileSize;}public String getFilePath() {return filePath;}public void setFilePath(String filePath) {this.filePath = filePath;}public String getFileMd5() {return fileMd5;}public void setFileMd5(String fileMd5) {this.fileMd5 = fileMd5;}public Integer getStatus() {return status;}public void setStatus(Integer status) {this.status = status;}public Date getCreateTime() {return createTime;}public void setCreateTime(Date createTime) {this.createTime = createTime;}
}
enums
枚举
DateTimePatternEnum
java">public enum DateTimePatternEnum {YYYY_MM("yyyyMM");private String pattern;public String getPattern() {return pattern;}public void setPattern(String pattern) {this.pattern = pattern;}DateTimePatternEnum(String pattern) {this.pattern = pattern;}
}
FileStatusEnum
java">public enum FileStatusEnum {ZERO(0,"禁用"),ONE(1,"启用");private Integer code;private String status;FileStatusEnum(Integer code, String status) {this.code = code;this.status = status;}public static Integer getByCode(Integer code) {for (FileStatusEnum fileStatusEnum : FileStatusEnum.values()) {if (fileStatusEnum.getCode().equals(code)) {return fileStatusEnum.getCode();}}return null;}public Integer getCode() {return code;}public void setCode(Integer code) {this.code = code;}public String getStatus() {return status;}public void setStatus(String status) {this.status = status;}
}FileTypeEnum
java">public enum FileTypeEnum {PNG(0,"png"),JPG(1,"jpg"),JPEG(2,"jpeg"),WEBP(3,"webp"),GIF(4,"gif");private Integer code;private String type;FileTypeEnum(Integer code, String type) {this.code = code;this.type = type;}public static Integer getByCode(String suffix){for (FileTypeEnum fileTypeEnum : FileTypeEnum.values()) {if (fileTypeEnum.getType().equals(suffix)) {return fileTypeEnum.getCode();}}return null;}public Integer getCode() {return code;}public void setCode(Integer code) {this.code = code;}public String getType() {return type;}public void setType(String type) {this.type = type;}
}ResponseCodeEnum
java">/*** 响应码枚举类，用于定义系统中各种操作的返回码及其对应的信息。*/
public enum ResponseCodeEnum {// 请求成功CODE_200(200, "请求成功"),// 请求的资源不存在CODE_404(404, "请求地址不存在"),// 请求参数错误CODE_600(600, "请求参数错误"),// 信息已存在，通常用于数据重复的场景CODE_601(601, "信息已经存在"),// 服务器内部错误，需要管理员处理CODE_500(500, "服务器返回错误，请联系管理员");// 响应码private Integer code;// 响应信息private String msg;/*** 构造方法，用于初始化枚举值。* @param code 响应码* @param msg 响应信息*/ResponseCodeEnum(Integer code, String msg) {this.code = code;this.msg = msg;}/*** 获取响应码。* @return 响应码*/public Integer getCode() {return code;}/*** 获取响应信息。* @return 响应信息*/public String getMsg() {return msg;}
}VO
FileInfoVo
java">public class FileInfoVo {private String fileName;private String filePath;private Long fileSize;private String fileId;private Integer status;public String getFileName() {return fileName;}public void setFileName(String fileName) {this.fileName = fileName;}public String getFilePath() {return filePath;}public void setFilePath(String filePath) {this.filePath = filePath;}public Long getFileSize() {return fileSize;}public void setFileSize(Long fileSize) {this.fileSize = fileSize;}public String getFileId() {return fileId;}public void setFileId(String fileId) {this.fileId = fileId;}public Integer getStatus() {return status;}public void setStatus(Integer status) {this.status = status;}
}
ResponseVO
java">/*** 响应数据的通用包装类，用于封装接口调用的返回结果。* <p>* 该类提供了对响应状态、响应码、响应信息和响应数据的封装，适用于各种接口返回数据的统一格式化。* 通过泛型T的支持，可以灵活地携带各种类型的响应数据。** @param <T> 响应数据的类型，使用泛型提供类型安全性和灵活性。*/
public class ResponseVO<T> {/*** 响应的状态，用于表示接口调用的总体状态，例如"success"表示成功。*/private String status;/*** 响应码，用于更详细地表示接口调用的结果状态，例如200表示成功。*/private Integer code;/*** 响应信息，用于对响应状态进行描述，例如"操作成功"。*/private String info;/*** 响应数据，接口调用的实际返回数据，其类型由泛型T指定。*/private T data;/*** 获取响应的状态。** @return 响应的状态字符串。*/public String getStatus() {return status;}/*** 设置响应的状态。** @param status 响应的状态字符串。*/public void setStatus(String status) {this.status = status;}/*** 获取响应码。** @return 响应的码值。*/public Integer getCode() {return code;}/*** 设置响应码。** @param code 响应的码值。*/public void setCode(Integer code) {this.code = code;}/*** 获取响应信息。** @return 响应的信息字符串。*/public String getInfo() {return info;}/*** 设置响应信息。** @param info 响应的信息字符串。*/public void setInfo(String info) {this.info = info;}/*** 获取响应数据。** @return 响应的数据对象，其类型为泛型T。*/public T getData() {return data;}/*** 设置响应数据。** @param data 响应的数据对象，其类型为泛型T。*/public void setData(T data) {this.data = data;}
}
异常处理器
java">/*** 业务异常类，用于表示在业务逻辑执行过程中发生的异常情况。* 继承自RuntimeException，因为它是一种非检查（Unchecked）异常，可以不强制在方法签名中声明。* 这使得业务异常的使用更加灵活，能够更准确地反映业务逻辑中的错误情况。*/
public class BusinessException extends RuntimeException {/*** 错误代码枚举，用于标准化错误代码和错误消息的映射。*/private ResponseCodeEnum codeEnum;/*** 错误代码，用于标识具体的错误类型。*/private Integer code;/*** 错误消息，用于描述错误的具体信息。*/private String message;/*** 带有错误消息和原因的构造函数。** @param message 错误消息* @param e 异常原因*/public BusinessException(String message, Throwable e) {super(message, e);this.message = message;}/*** 带有错误消息的构造函数。** @param message 错误消息*/public BusinessException(String message) {super(message);this.message = message;}/*** 带有原因的构造函数。** @param e 异常原因*/public BusinessException(Throwable e) {super(e);}/*** 使用错误代码枚举构造业务异常。** @param codeEnum 错误代码枚举，包含错误代码、错误消息等信息。*/public BusinessException(ResponseCodeEnum codeEnum) {super(codeEnum.getMsg());this.codeEnum = codeEnum;this.code = codeEnum.getCode();this.message = codeEnum.getMsg();}/*** 带有错误代码和错误消息的构造函数。** @param code 错误代码* @param message 错误消息*/public BusinessException(Integer code, String message) {super(message);this.code = code;this.message = message;}/*** 获取错误代码枚举。** @return 错误代码枚举*/public ResponseCodeEnum getCodeEnum() {return codeEnum;}/*** 获取错误代码。** @return 错误代码*/public Integer getCode() {return code;}/*** 获取错误消息。** @return 错误消息*/@Overridepublic String getMessage() {return message;}/*** 重写fillInStackTrace方法，返回当前异常实例。* 业务异常中通常不需要堆栈跟踪信息，因此这个重写方法用于提高异常处理的性能。** @return 当前异常实例*//*** 重写fillInStackTrace 业务异常不需要堆栈信息，提高效率.*/@Overridepublic Throwable fillInStackTrace() {return this;}
}
Mappers
FileInfoMapper
java">@Mapper
public interface FileInfoMapper {FileInfoVo selectByFileId(String fileId);void insert(FileInfoDto fileInfoDto);FileInfoDto selectByFileMd5(String fileMd5);
}FileInfoMapper.xml
java"><?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapperPUBLIC "-//mybatis.org//DTD Mapper 3.0//EN""http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.hhh.mappers.FileInfoMapper"><select id="selectByFileId" resultType="com.hhh.entity.vo.FileInfoVo">select file_name as fileName, file_path as filePath, file_size as fileSize, file_id as fileId,status as statusfrom file_infowhere file_id = #{fileId}</select><select id="selectByFileMd5" resultType="com.hhh.entity.dto.FileInfoDto">select file_name as fileName, file_path as filePath, file_size as fileSize, file_id as fileId, file_type as fileType, file_md5 as fileMd5, status as status, create_time as createTimefrom file_infowhere file_md5 = #{fileMd5}</select><insert id="insert">insert into file_info<trim prefix="(" suffix=")" suffixOverrides=","><if test="fileId != null">file_id,</if><if test="fileName != null">file_name,</if><if test="filePath != null">file_path,</if><if test="fileType != null">file_type,</if><if test="fileSize != null">file_size,</if><if test="fileMd5 != null">file_md5,</if><if test="status != null">status,</if><if test="createTime != null">create_time,</if></trim><trim prefix="values (" suffix=")" suffixOverrides=","><if test="fileId != null">#{fileId},</if><if test="fileName != null">#{fileName},</if><if test="filePath != null">#{filePath},</if><if test="fileType != null">#{fileType},</if><if test="fileSize != null">#{fileSize},</if><if test="fileMd5 != null">#{fileMd5},</if><if test="status != null">#{status},</if><if test="createTime != null">#{createTime},</if></trim></insert>
</mapper>Service
UploadService
java">public interface UploadService {FileInfoVo upload(MultipartFile file) throws IOException, NoSuchAlgorithmException;FileInfoVo getFileInfo(String fileId);
}
UploadServiceImpl
java">@Service("UploadService")
public class UploadServiceImpl implements UploadService {private static final Logger logger = LoggerFactory.getLogger(UploadServiceImpl.class);private static final List<String> ALLOWED_EXTENSIONS = Arrays.asList("jpg", "jpeg", "png", "gif", "webp");@Resourceprivate AppConfig appConfig;@Resourceprivate FileInfoMapper fileInfoMapper;@Override@Transactional(rollbackFor = Exception.class)public FileInfoVo upload(MultipartFile file) throws IOException, NoSuchAlgorithmException {// 计算MD5String fileMd5 = calculateMD5(file.getInputStream());// 查询MD5是否存在FileInfoDto existingFileInfo = fileInfoMapper.selectByFileMd5(fileMd5);if (existingFileInfo != null) {throw new BusinessException("您已经上传过该文件了，没必要重复上传");}// 初始化 FileInfoDtoFileInfoDto fileInfoDto = createFileInfoDto(file, fileMd5);// 检查文件格式是否被允许if (!isAllowed(file.getOriginalFilename())) {throw new BusinessException("文件格式错误，请上传jpg, png, webp, jpeg, gif等图片格式");}// 构建文件存储路径String projectFolder = appConfig.getProjectFolder() + Constants.FILE_PATH;String datePath = LocalDate.now().format(DateTimeFormatter.ofPattern(DateTimePatternEnum.YYYY_MM.getPattern()));File uploadFileProjectFolder = new File(projectFolder + "/" + datePath);createDirectoryIfNotExists(uploadFileProjectFolder);// 构建文件夹路径String randomString1 = StringUtil.getRandomString(10);File fileFolder = new File(uploadFileProjectFolder.getPath() + "/" + randomString1);createDirectoryIfNotExists(fileFolder);// 构建新文件路径String fileName = file.getOriginalFilename();File newFile = new File(fileFolder.getPath() + "/" + fileName);// 设置文件信息 DTOsetFileInfoDto(fileInfoDto, file, datePath, randomString1);// 保存文件信息fileInfoMapper.insert(fileInfoDto);// 保存文件和带水印的版本saveFileAndWatermark(file, newFile, fileFolder, fileName);// 返回文件信息 VOreturn createFileInfoVo(fileInfoDto, file);}private FileInfoDto createFileInfoDto(MultipartFile file, String fileMd5) {FileInfoDto fileInfoDto = new FileInfoDto();fileInfoDto.setFileMd5(fileMd5);fileInfoDto.setFileId(StringUtil.getRandomString(15));return fileInfoDto;}private void createDirectoryIfNotExists(File directory) {if (!directory.exists()) {directory.mkdirs();}}private void setFileInfoDto(FileInfoDto fileInfoDto, MultipartFile file, String datePath, String randomString1) {String fileName = file.getOriginalFilename();fileInfoDto.setFileName(fileName);fileInfoDto.setFileType(FileTypeEnum.getByCode(StringUtil.getFileSuffix(fileName)));fileInfoDto.setFileSize(file.getSize());fileInfoDto.setFilePath(Constants.FILE_PATH + "/" + datePath + "/" + randomString1 + "/" + fileName);fileInfoDto.setStatus(FileStatusEnum.ONE.getCode());fileInfoDto.setCreateTime(new Date());}private void saveFileAndWatermark(MultipartFile file, File newFile, File fileFolder, String fileName) throws IOException {// 保存上传文件到服务器file.transferTo(newFile);// 构建带水印的文件名String fileNameWithoutExtension = fileName.substring(0, fileName.lastIndexOf("."));String suffix = StringUtil.getSuffix(fileName);String watermarkName = fileNameWithoutExtension + "_" + suffix;File newWatermarkFile = new File(fileFolder.getPath() + "/" + watermarkName);// 为文件添加水印并压缩addWatermarkAndCompress(newFile, newWatermarkFile, "贺浩浩");}private FileInfoVo createFileInfoVo(FileInfoDto fileInfoDto, MultipartFile file) {FileInfoVo fileInfoVo = new FileInfoVo();fileInfoVo.setFileId(fileInfoDto.getFileId());fileInfoVo.setFileName(fileInfoDto.getFileName());fileInfoVo.setFilePath(fileInfoDto.getFilePath());fileInfoVo.setFileSize(file.getSize());fileInfoDto.setStatus(FileStatusEnum.ONE.getCode());return fileInfoVo;}/*** 计算输入流的MD5哈希值。** 此方法通过读取输入流中的数据，然后使用MD5算法计算其哈希值。* MD5是一种广泛使用的加密散列函数，产生一个128位（16字节）的散列值。** @param inputStream 要计算MD5哈希值的输入流。* @return 输入流数据的MD5哈希值的字符串表示。* @throws NoSuchAlgorithmException 如果MD5算法不可用。* @throws IOException 如果在读取输入流时发生错误。*/private String calculateMD5(InputStream inputStream) throws NoSuchAlgorithmException, IOException {// 实例化MD5消息摘要算法MessageDigest md = MessageDigest.getInstance("MD5");// 创建一个缓冲区，用于从输入流中读取数据byte[] buffer = new byte[1024];int bytesRead;// 循环读取输入流中的数据，并更新消息摘要while ((bytesRead = inputStream.read(buffer)) != -1) {md.update(buffer, 0, bytesRead);}// 计算消息摘要byte[] digest = md.digest();// 将消息摘要转换为十六进制字符串StringBuilder sb = new StringBuilder();for (byte b : digest) {sb.append(String.format("%02x", b));}// 返回MD5哈希值的字符串表示return sb.toString();}/*** 检查文件名是否允许。** 此方法通过检查文件名的扩展名来确定文件名是否被允许。文件名必须包含至少一个点（.）* 以标识扩展名，并且扩展名必须在预定义的允许扩展名列表中。** @param fileName 要检查的文件名。* @return 如果文件名的扩展名被允许，则返回true；否则返回false。*/private Boolean isAllowed(String fileName) {// 检查文件名是否为空或不包含点（.）if(fileName == null || fileName.lastIndexOf(".") == -1){return false;}// 提取文件名的扩展名，并转换为小写String extension = fileName.substring(fileName.lastIndexOf('.') + 1).toLowerCase();// 检查提取的扩展名是否在允许的扩展名列表中return ALLOWED_EXTENSIONS.contains(extension);}/*** 给图片添加水印并压缩保存。** 此方法接收原始图片文件、目标输出文件和水印文本作为参数，它将原始图片读入，* 添加水印后，按照原始尺寸进行压缩，并保存到目标文件中。** @param originalFile 原始图片文件，添加水印和压缩的基础文件。* @param outputFile 添加水印并压缩后的图片保存位置。* @param watermarkText 要添加的水印文本。* @throws IOException 如果读取或写入文件发生错误。*/private void addWatermarkAndCompress(File originalFile, File outputFile,String watermarkText) throws IOException {// 读取原始图片BufferedImage originalImage = ImageIO.read(originalFile);// 添加水印BufferedImage watermarkedImage = addWatermark(originalImage, watermarkText);// 获取原图尺寸，以保持压缩后的图片尺寸与原图相同// 获取原图尺寸int originalWidth = originalImage.getWidth();int originalHeight = originalImage.getHeight();// 使用Thumbnails.of方法对添加水印后的图片进行缩放和压缩// 按比例缩放并压缩Thumbnails.of(watermarkedImage).size(originalWidth, originalHeight).outputQuality(0.4) // 调整画质压缩.toFile(outputFile);}/*** 给图片添加水印。** @param image 原始图片。* @param watermarkText 水印文本。* @return 添加了水印的图片。*/private BufferedImage addWatermark(BufferedImage image, String watermarkText) {// 获取原始图片的宽度和高度int imageWidth = image.getWidth();int imageHeight = image.getHeight();// 创建Graphics2D对象，用于在图片上绘制水印// 创建用于绘制水印的Graphics2D对象Graphics2D g2d = (Graphics2D) image.getGraphics();// 设置透明度，使水印呈现半透明效果// 设置水印的属性AlphaComposite alphaChannel = AlphaComposite.getInstance(AlphaComposite.SRC_OVER, 0.3f);g2d.setComposite(alphaChannel);// 设置水印文字颜色为灰色g2d.setColor(Color.GRAY);// 设置水印文字的字体、大小和样式// 使用支持中文的字体，例如SimHei（黑体）Font font = new Font("SimHei", Font.BOLD, 36);g2d.setFont(font);// 获取水印文字的尺寸信息FontMetrics fontMetrics = g2d.getFontMetrics();Rectangle2D rect = fontMetrics.getStringBounds(watermarkText, g2d);int textWidth = (int) rect.getWidth();int textHeight = (int) rect.getHeight();// 用于随机生成水印位置偏移量Random random = new Random();// 平铺方式添加水印，通过控制行间距和文字在行内的偏移，实现错落有致的布局效果// 平铺方式添加水印，单双行错开并随机偏移for (int y = 0; y < imageHeight; y += textHeight + 100) {// 判断当前行为偶数行还是奇数行，奇数行文字向右偏移boolean oddRow = (y / (textHeight + 100)) % 2 == 0;for (int x = oddRow ? 0 : textWidth / 2; x < imageWidth; x += textWidth + 300) {// 随机生成水平和垂直偏移量，使水印位置略有变化，避免整齐排列int xOffset = random.nextInt(100) - 50; // 随机偏移 -50 到 50 像素int yOffset = random.nextInt(50) - 25; // 随机偏移 -25 到 25 像素// 在图片上绘制水印文字，位置略有偏移g2d.drawString(watermarkText, x + xOffset, y + yOffset);}}// 释放Graphics2D资源g2d.dispose();// 返回添加了水印的图片return image;}@Overridepublic FileInfoVo getFileInfo(String fileId) {FileInfoVo fileInfoVo = fileInfoMapper.selectByFileId(fileId);if(null == fileInfoVo){throw new BusinessException("文件id错误，请检查之后重新请求");}if(fileInfoVo.getStatus().equals(FileStatusEnum.ZERO.getCode())){throw new BusinessException("文件已经被禁用了，无法查看");}return fileInfoVo;}}工具类
FileUtils
java">public class FileUtils {private static final Logger logger = LoggerFactory.getLogger(FileUtils.class);public static void readFile(HttpServletResponse response, String filePath) {// 如果文件路径不合法，则直接返回if (!pathIsOk(filePath)) {return;}OutputStream out = null;FileInputStream in = null;try {File file = new File(filePath);// 如果文件不存在，则直接返回if (!file.exists()) {return;}in = new FileInputStream(file); // 打开文件输入流byte[] byteData = new byte[1024]; // 定义缓冲区out = response.getOutputStream(); // 获取响应输出流int len = 0;// 读取文件并写入响应输出流while ((len = in.read(byteData)) != -1) {out.write(byteData, 0, len);}out.flush();} catch (Exception e) {logger.error("读取文件异常", e);} finally {// 关闭输出流if (out != null) {try {out.close();} catch (IOException e) {logger.error("IO异常", e);}}// 关闭输入流if (in != null) {try {in.close();} catch (IOException e) {logger.error("IO异常", e);}}}}public static boolean pathIsOk(String filePath) {if(isEmpty(filePath)){return true;}if(filePath.contains("../") || filePath.contains("..\\")){return false;}return true;}public static boolean isEmpty(String str) {if (null == str || "".equals(str) || "null".equals(str) || "\u0000".equals(str)) {return true;} else if ("".equals(str.trim())) {return true;}return false;}
}StringUtil
java">public class StringUtil {public static String getSuffix(String fileName){String suffix = fileName.substring(fileName.lastIndexOf('.')).toLowerCase();return suffix;}public static String getFileSuffix(String fileName){String suffix = fileName.substring(fileName.lastIndexOf('.') + 1).toLowerCase();return suffix;}public static final String getRandomString(Integer count){return RandomStringUtils.random(count,true,true);}
}效果
不带水印访问
带水印访问
总结
至于带水印我的实现是这样的，大家可以根据自己的思路来决定
比如没有登录访问的是水印版本，登录之后才能访问无水印版本
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