新增后端带条件导出功能（示例见用户管理控制器）

eladmin-common/src/main/java/me/zhengjie/utils/FileUtil.java

 package me.zhengjie.utils;
 
+import cn.hutool.core.io.IoUtil;
 import cn.hutool.core.util.IdUtil;
+import cn.hutool.poi.excel.ExcelUtil;
+import cn.hutool.poi.excel.ExcelWriter;
 import org.springframework.web.multipart.MultipartFile;
 
+import javax.servlet.ServletOutputStream;
+import javax.servlet.http.HttpServletResponse;
 import java.io.*;
 import java.text.DecimalFormat;
+import java.util.List;
+import java.util.Map;
 
 /**
  * File工具类，扩展 hutool 工具包
@@ -139,4 +146,32 @@ public class FileUtil extends cn.hutool.core.io.FileUtil {
         ins.close();
         return file;
     }
+
+    /**
+     * 导出excel
+     * @param list
+     * @return
+     * @throws Exception
+     */
+    public static void downloadExcel(List<Map<String, Object>> list, HttpServletResponse response){
+        // 通过工具类创建writer
+        ExcelWriter writer = ExcelUtil.getWriter();
+        // 一次性写出内容，使用默认样式，强制输出标题
+        writer.write(list, true);
+        //response为HttpServletResponse对象
+        response.setContentType("application/vnd.ms-excel;charset=utf-8");
+        //test.xls是弹出下载对话框的文件名，不能为中文，中文请自行编码
+        response.setHeader("Content-Disposition","attachment;filename=file.xls");
+        ServletOutputStream out= null;
+        try {
+            out = response.getOutputStream();
+        } catch (IOException e) {
+            e.printStackTrace();
+        }
+        writer.flush(out, true);
+        // 关闭writer，释放内存
+        writer.close();
+        //此处记得关闭输出Servlet流
+        IoUtil.close(out);
+    }
 }

eladmin-system/src/main/java/me/zhengjie/modules/system/rest/RoleController.java

@@ -5,7 +5,6 @@ import me.zhengjie.aop.log.Log;
 import me.zhengjie.modules.system.domain.Role;
 import me.zhengjie.exception.BadRequestException;
 import me.zhengjie.modules.system.service.RoleService;
-import me.zhengjie.modules.system.service.dto.MenuQueryCriteria;
 import me.zhengjie.modules.system.service.dto.RoleQueryCriteria;
 import me.zhengjie.modules.system.service.dto.RoleSmallDTO;
 import me.zhengjie.utils.SecurityUtils;

eladmin-system/src/main/java/me/zhengjie/modules/system/rest/UserController.java

@@ -26,6 +26,7 @@ import org.springframework.util.ObjectUtils;
 import org.springframework.validation.annotation.Validated;
 import org.springframework.web.bind.annotation.*;
 import org.springframework.web.multipart.MultipartFile;
+import javax.servlet.http.HttpServletResponse;
 import java.util.*;
 import java.util.stream.Collectors;
 
@@ -55,6 +56,13 @@ public class UserController {
     @Autowired
     private VerificationCodeService verificationCodeService;
 
+    @Log("导出用户数据")
+    @GetMapping(value = "/users/download")
+    @PreAuthorize("hasAnyRole('ADMIN','USER_ALL','USER_SELECT')")
+    public void update(HttpServletResponse response, UserQueryCriteria criteria){
+        userService.download(userService.queryAll(criteria), response);
+    }
+
     @Log("查询用户")
     @GetMapping(value = "/users")
     @PreAuthorize("hasAnyRole('ADMIN','USER_ALL','USER_SELECT')")

eladmin-system/src/main/java/me/zhengjie/modules/system/service/RoleService.java

@@ -10,6 +10,7 @@ import org.springframework.cache.annotation.CacheEvict;
 import org.springframework.cache.annotation.Cacheable;
 import org.springframework.data.domain.Pageable;
 
+import javax.servlet.http.HttpServletResponse;
 import java.util.List;
 import java.util.Set;
 
@@ -86,6 +87,7 @@ public interface RoleService {
      * @param pageable
      * @return
      */
+    @Cacheable(keyGenerator = "keyGenerator")
     Object queryAll(Pageable pageable);
 
     /**
@@ -94,5 +96,14 @@ public interface RoleService {
      * @param criteria
      * @return
      */
+    @Cacheable(keyGenerator = "keyGenerator")
     Object queryAll(RoleQueryCriteria criteria, Pageable pageable);
+
+    /**
+     * queryAll
+     * @param criteria
+     * @return
+     */
+    @Cacheable(keyGenerator = "keyGenerator")
+    List<RoleDTO> queryAll(RoleQueryCriteria criteria);
 }

eladmin-system/src/main/java/me/zhengjie/modules/system/service/UserService.java

@@ -9,6 +9,9 @@ import org.springframework.cache.annotation.CacheEvict;
 import org.springframework.cache.annotation.Cacheable;
 import org.springframework.data.domain.Pageable;
 
+import javax.servlet.http.HttpServletResponse;
+import java.util.List;
+
 /**
  * @author Zheng Jie
  * @date 2018-11-23
@@ -80,4 +83,9 @@ public interface UserService {
 
     @Cacheable(keyGenerator = "keyGenerator")
     Object queryAll(UserQueryCriteria criteria, Pageable pageable);
+
+    @Cacheable(keyGenerator = "keyGenerator")
+    List<UserDTO> queryAll(UserQueryCriteria criteria);
+
+    void download(List<UserDTO> queryAll, HttpServletResponse response);
 }

eladmin-system/src/main/java/me/zhengjie/modules/system/service/impl/RoleServiceImpl.java

@@ -10,6 +10,7 @@ import me.zhengjie.modules.system.service.dto.RoleQueryCriteria;
 import me.zhengjie.modules.system.service.dto.RoleSmallDTO;
 import me.zhengjie.modules.system.service.mapper.RoleMapper;
 import me.zhengjie.modules.system.service.mapper.RoleSmallMapper;
+import me.zhengjie.utils.FileUtil;
 import me.zhengjie.utils.PageUtil;
 import me.zhengjie.utils.QueryHelp;
 import me.zhengjie.utils.ValidationUtil;
@@ -19,6 +20,8 @@ import org.springframework.data.domain.Pageable;
 import org.springframework.stereotype.Service;
 import org.springframework.transaction.annotation.Propagation;
 import org.springframework.transaction.annotation.Transactional;
+
+import javax.servlet.http.HttpServletResponse;
 import java.util.*;
 import java.util.stream.Collectors;
 
@@ -44,6 +47,11 @@ public class RoleServiceImpl implements RoleService {
         return roleMapper.toDto(roleRepository.findAll(pageable).getContent());
     }
 
+    @Override
+    public List<RoleDTO> queryAll(RoleQueryCriteria criteria) {
+        return roleMapper.toDto(roleRepository.findAll((root, criteriaQuery, criteriaBuilder) -> QueryHelp.getPredicate(root,criteria,criteriaBuilder)));
+    }
+
     @Override
     public Object queryAll(RoleQueryCriteria criteria, Pageable pageable) {
         Page<Role> page = roleRepository.findAll((root, criteriaQuery, criteriaBuilder) -> QueryHelp.getPredicate(root,criteria,criteriaBuilder),pageable);

eladmin-system/src/main/java/me/zhengjie/modules/system/service/impl/UserServiceImpl.java

 package me.zhengjie.modules.system.service.impl;
 
+import cn.hutool.core.io.IoUtil;
+import cn.hutool.poi.excel.ExcelUtil;
+import cn.hutool.poi.excel.ExcelWriter;
 import me.zhengjie.modules.monitor.service.RedisService;
 import me.zhengjie.modules.system.domain.User;
 import me.zhengjie.exception.EntityExistException;
 import me.zhengjie.exception.EntityNotFoundException;
 import me.zhengjie.modules.system.repository.UserRepository;
 import me.zhengjie.modules.system.service.UserService;
+import me.zhengjie.modules.system.service.dto.RoleSmallDTO;
 import me.zhengjie.modules.system.service.dto.UserDTO;
 import me.zhengjie.modules.system.service.dto.UserQueryCriteria;
 import me.zhengjie.modules.system.service.mapper.UserMapper;
+import me.zhengjie.utils.FileUtil;
 import me.zhengjie.utils.PageUtil;
 import me.zhengjie.utils.QueryHelp;
 import me.zhengjie.utils.ValidationUtil;
@@ -18,8 +23,11 @@ import org.springframework.data.domain.Pageable;
 import org.springframework.stereotype.Service;
 import org.springframework.transaction.annotation.Propagation;
 import org.springframework.transaction.annotation.Transactional;
-import java.util.Date;
-import java.util.Optional;
+import javax.servlet.ServletOutputStream;
+import javax.servlet.http.HttpServletResponse;
+import java.io.IOException;
+import java.util.*;
+import java.util.stream.Collectors;
 
 /**
  * @author Zheng Jie
@@ -44,6 +52,12 @@ public class UserServiceImpl implements UserService {
         return PageUtil.toPage(page.map(userMapper::toDto));
     }
 
+    @Override
+    public List<UserDTO> queryAll(UserQueryCriteria criteria) {
+        List<User> users = userRepository.findAll((root, criteriaQuery, criteriaBuilder) -> QueryHelp.getPredicate(root,criteria,criteriaBuilder));
+        return userMapper.toDto(users);
+    }
+
     @Override
     public UserDTO findById(long id) {
         Optional<User> user = userRepository.findById(id);
@@ -144,4 +158,25 @@ public class UserServiceImpl implements UserService {
     public void updateEmail(String username, String email) {
         userRepository.updateEmail(username,email);
     }
+
+    @Override
+    public void download(List<UserDTO> queryAll, HttpServletResponse response) {
+        List<Map<String, Object>> list = new ArrayList<>();
+        for (UserDTO userDTO : queryAll) {
+            List roles = userDTO.getRoles().stream().map(RoleSmallDTO::getName).collect(Collectors.toList());
+            Map map = new LinkedHashMap();
+            map.put("用户名", userDTO.getUsername());
+            map.put("头像", userDTO.getAvatar());
+            map.put("邮箱", userDTO.getEmail());
+            map.put("状态", userDTO.getEnabled() ? "启用" : "禁用");
+            map.put("手机号码", userDTO.getPhone());
+            map.put("角色", roles);
+            map.put("部门", userDTO.getDept().getName());
+            map.put("岗位", userDTO.getJob().getName());
+            map.put("最后修改密码的时间", userDTO.getLastPasswordResetTime());
+            map.put("创建日期", userDTO.getCreateTime());
+            list.add(map);
+        }
+        FileUtil.downloadExcel(list, response);
+    }
 }

eladmin-system/src/main/resources/logback.xml

@@ -24,7 +24,8 @@
         <appender-ref ref="console" />
     </logger>
 
-    <logger name="jdbc.resultsettable" level="INFO" additivity="false">
+    <!--  如想看到表格数据，将OFF改为INFO  -->
+    <logger name="jdbc.resultsettable" level="OFF" additivity="false">
         <appender-ref ref="console" />
     </logger>
 

pom.xml

@@ -155,6 +155,11 @@
             <artifactId>ip2region</artifactId>
             <version>1.7.2</version>
         </dependency>
+        <dependency>
+            <groupId>org.apache.poi</groupId>
+            <artifactId>poi</artifactId>
+            <version>3.17</version>
+        </dependency>
 
         <!-- fastjson -->
         <dependency>