1.完成对前端到后端跨域问题的解决2.完成基本的销售导入代码开发3.测试导入数据2条，责任中心导入时有重复插入的问题

src/main/java/com/example/backend/config/CorsConfig.java

-package com.example.backend.config;
-
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.web.cors.CorsConfiguration;
 import org.springframework.web.cors.UrlBasedCorsConfigurationSource;
 import org.springframework.web.filter.CorsFilter;
+import org.springframework.web.servlet.config.annotation.CorsRegistry;
+import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;
+
 
 @Configuration
-public class CorsConfig {
+public class CorsConfig implements WebMvcConfigurer {
+
+    @Override
+    public void addCorsMappings(CorsRegistry registry) {
+        registry.addMapping("/**")
+                .allowedOriginPatterns("*")
+                .allowedMethods("GET", "POST", "PUT", "DELETE", "OPTIONS")
+                .allowedHeaders("*")
+                .allowCredentials(true)
+                .maxAge(3600);
+    }
 
     @Bean
     public CorsFilter corsFilter() {
-        UrlBasedCorsConfigurationSource source = new UrlBasedCorsConfigurationSource();
         CorsConfiguration config = new CorsConfiguration();
+        config.addAllowedOriginPattern("*");
         config.setAllowCredentials(true);
-        // 设置允许的域名，*表示允许所有域名
-        config.addAllowedOrigin("*");
-        // 设置允许的请求头
-        config.addAllowedHeader("*");
-        // 设置允许的请求方法
         config.addAllowedMethod("*");
+        config.addAllowedHeader("*");
+
+        UrlBasedCorsConfigurationSource source = new UrlBasedCorsConfigurationSource();
         source.registerCorsConfiguration("/**", config);
         return new CorsFilter(source);
     }
-
-}
+}

src/main/java/com/example/backend/controller/contract/PurchaseContractController.java

 package com.example.backend.controller.contract;
 
+import com.example.backend.service.contract.PurchaseContractService;
 import com.example.backend.service.contract.SalesContractService;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.http.ResponseEntity;
 public class PurchaseContractController {
 
     @Autowired
-    private SalesContractService salesContractService;
+    private PurchaseContractService purchaseContractService;
 
     /**
      * 导入Excel文件
     public ResponseEntity<Map<String, Object>> importExcel(@RequestParam("file") MultipartFile file) {
         Map<String, Object> result = new HashMap<>();
         try {
-            boolean success = salesContractService.importExcel(file);
+            boolean success = purchaseContractService.importExcel(file);
             if (success) {
                 result.put("code", 200);
                 result.put("message", "导入成功");

src/main/java/com/example/backend/controller/contract/SalesContractController.java

 package com.example.backend.controller.contract;
 
 import com.example.backend.service.contract.SalesContractService;
+import com.example.backend.util.ExcelImportResult;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.http.ResponseEntity;
 import org.springframework.web.bind.annotation.*;
  */
 @RestController
 @RequestMapping("/salesContract")
+@CrossOrigin(origins = "*") // 添加这个注解
 public class SalesContractController {
 
     @Autowired
     public ResponseEntity<Map<String, Object>> importExcel(@RequestParam("file") MultipartFile file) {
         Map<String, Object> result = new HashMap<>();
         try {
-            boolean success = salesContractService.importExcel(file);
-            if (success) {
+            ExcelImportResult<Void> importResult = salesContractService.importExcelSales(file);
+
+            if (importResult.isSuccess()) {
                 result.put("code", 200);
-                result.put("message", "导入成功");
+                result.put("success", true);
+                result.put("message", importResult.getMessage());
+                // 添加统计信息
+                if (importResult.getTotalCount() != null) {
+                    result.put("totalCount", importResult.getTotalCount());
+                    result.put("successCount", importResult.getSuccessCount());
+                    result.put("errorCount", importResult.getErrorCount());
+                }
             } else {
                 result.put("code", 500);
-                result.put("message", "导入失败");
+                result.put("success", false);
+                result.put("message", importResult.getMessage());
+                // 添加详细的错误信息
+                if (importResult.getErrors() != null && !importResult.getErrors().isEmpty()) {
+                    result.put("errors", importResult.getErrors());
+                    result.put("errorCount", importResult.getErrors().size());
+                }
             }
         } catch (Exception e) {
             result.put("code", 500);
-            result.put("message", "导入失败：" + e.getMessage());
+            result.put("success", false);
+            result.put("message", "系统处理异常：" + e.getMessage());
             e.printStackTrace();
         }
         return ResponseEntity.ok(result);
     }
-
-}
+}

src/main/java/com/example/backend/service/contract/SalesContractService.java

 package com.example.backend.service.contract;
 
 import com.example.backend.entity.contract.SalesContractEntity;
+import com.example.backend.util.ExcelImportResult;
 import org.springframework.stereotype.Component;
 import org.springframework.stereotype.Service;
 import org.springframework.web.multipart.MultipartFile;
  */
 
 public interface SalesContractService {
+    ExcelImportResult<Void> importExcelSales(MultipartFile file);
 
-    /**
-     * 导入Excel文件
-     * @param file Excel文件
-     * @return 导入结果
-     */
-    boolean importExcel(MultipartFile file);
-
-    /**
-     * 保存合同及明细
-     * @param contract 销售合同
-     * @param products 产品明细
-     * @param deliveries 交货明细
-     * @param payments 付款明细
-     * @param qualities 质量保证明细
-     * @param terms 其他条款
-     * @return 保存结果
-     */
-//    boolean saveContractWithDetails(SalesContractEntity contract,
-//                                    List<?> products,
-//                                    List<?> deliveries,
-//                                    List<?> payments,
-//                                    List<?> qualities,
-//                                    List<?> terms);
 
 }

src/main/java/com/example/backend/service/contract/impl/PurchaseContractServiceImpl.java

 import com.example.backend.excel.*;
 import com.example.backend.mapper.contract.*;
 import com.example.backend.service.contract.PurchaseContractService;
+import com.example.backend.util.ExcelUtils;
 import org.springframework.beans.BeanUtils;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.stereotype.Service;

src/main/java/com/example/backend/excel/DateUtils.java → src/main/java/com/example/backend/util/DateUtils.java

-package com.example.backend.excel;
+package com.example.backend.util;
 
 import java.time.LocalDateTime;
 import java.time.format.DateTimeFormatter;

src/main/java/com/example/backend/util/ExcelImportResult.java

+package com.example.backend.util;
+
+import lombok.Data;
+import java.util.List;
+
+@Data
+public class ExcelImportResult<T> {
+    
+    private boolean success;
+    private String message;
+    private List<String> errors;
+    private T data;
+    private Integer totalCount;
+    private Integer successCount;
+    private Integer errorCount;
+    
+    public ExcelImportResult() {}
+    
+    // 成功结果
+    public static <T> ExcelImportResult<T> success(String message) {
+        return success(message, null);
+    }
+    
+    public static <T> ExcelImportResult<T> success(String message, T data) {
+        ExcelImportResult<T> result = new ExcelImportResult<>();
+        result.setSuccess(true);
+        result.setMessage(message);
+        result.setData(data);
+        return result;
+    }
+    
+    public static <T> ExcelImportResult<T> success(String message, Integer totalCount, Integer successCount) {
+        ExcelImportResult<T> result = new ExcelImportResult<>();
+        result.setSuccess(true);
+        result.setMessage(message);
+        result.setTotalCount(totalCount);
+        result.setSuccessCount(successCount);
+        result.setErrorCount(totalCount - successCount);
+        return result;
+    }
+    
+    // 失败结果
+    public static <T> ExcelImportResult<T> error(String message) {
+        return error(message, null);
+    }
+    
+    public static <T> ExcelImportResult<T> error(String message, List<String> errors) {
+        ExcelImportResult<T> result = new ExcelImportResult<>();
+        result.setSuccess(false);
+        result.setMessage(message);
+        result.setErrors(errors);
+        if (errors != null) {
+            result.setErrorCount(errors.size());
+        }
+        return result;
+    }
+}

src/main/java/com/example/backend/excel/ExcelUtil.java → src/main/java/com/example/backend/util/ExcelUtil.java

-package com.example.backend.excel;
+package com.example.backend.util;
 
 import com.alibaba.excel.EasyExcel;
 import com.alibaba.excel.context.AnalysisContext;
 import com.alibaba.excel.event.AnalysisEventListener;
 import com.alibaba.excel.metadata.data.ReadCellData;
+import com.example.backend.excel.*;
 import org.springframework.web.multipart.MultipartFile;
 
 import java.io.IOException;

src/main/java/com/example/backend/excel/ExcelUtils.java → src/main/java/com/example/backend/util/ExcelUtils.java

-package com.example.backend.excel;
+package com.example.backend.util;
 
 import com.alibaba.excel.EasyExcel;
 import com.alibaba.excel.context.AnalysisContext;
 import com.alibaba.excel.event.AnalysisEventListener;
 import com.alibaba.excel.metadata.data.CellData;
 import com.alibaba.excel.metadata.data.ReadCellData;
+import com.example.backend.excel.*;
 import org.springframework.web.multipart.MultipartFile;
 
 import java.io.IOException;

src/main/java/com/example/backend/util/ResponseUtil.java

+package com.example.backend.util;
+
+import org.springframework.http.HttpStatus;
+import org.springframework.http.ResponseEntity;
+
+import java.util.List;
+
+public class ResponseUtil {
+    
+    /**
+     * 成功响应
+     */
+    public static <T> ResponseEntity<ExcelImportResult<T>> success(String message) {
+        return ResponseEntity.ok(ExcelImportResult.success(message));
+    }
+    
+    public static <T> ResponseEntity<ExcelImportResult<T>> success(String message, T data) {
+        return ResponseEntity.ok(ExcelImportResult.success(message, data));
+    }
+    
+    public static <T> ResponseEntity<ExcelImportResult<T>> success(String message, Integer totalCount, Integer successCount) {
+        return ResponseEntity.ok(ExcelImportResult.success(message, totalCount, successCount));
+    }
+    
+    /**
+     * 失败响应
+     */
+    public static <T> ResponseEntity<ExcelImportResult<T>> error(String message) {
+        return ResponseEntity.status(HttpStatus.BAD_REQUEST)
+                .body(ExcelImportResult.error(message));
+    }
+    
+    public static <T> ResponseEntity<ExcelImportResult<T>> error(String message, List<String> errors) {
+        return ResponseEntity.status(HttpStatus.BAD_REQUEST)
+                .body(ExcelImportResult.error(message, errors));
+    }
+    
+    public static <T> ResponseEntity<ExcelImportResult<T>> error(HttpStatus status, String message, List<String> errors) {
+        return ResponseEntity.status(status)
+                .body(ExcelImportResult.error(message, errors));
+    }
+}