根据Table内容自动生成实体类

比眉伴天荒 2022-04-11 08:44 286阅读 0赞

### 一、前言 ###

最近负责各式各样三方接口对接，从百度，阿里，腾讯，网易再到各种小三方，调三方接口难度不大，但是封装大量的参数让人不胜其烦，于是，在下一寻思，何不写个自动生成工具？

说干就干，根据阅读三方文档的经验来看，他们提供的参数信息一般是以表格形式展示，那么我的技术需求，首先的就是解析表单，接着，得到参数后，如果有合适的模版，不就可以了生成目标实体了么，vm模版，决定就是你了。

\#\#\#\#\#\#\#\#注意

本工具类暂时只支持docx格式生成java实体类，其他的操作，后续补充。。。。。。。。

### 二、环境准备 ###

**1、引入所需pom文件**

<dependency>
                <groupId>org.apache.velocity</groupId>
                <artifactId>velocity-engine-core</artifactId>
                <version>2.0</version>
            </dependency>
    
            <dependency>
                <groupId>org.apache.poi</groupId>
                <artifactId>poi-ooxml</artifactId>
                <version>3.11</version>
            </dependency>
    
            <dependency>
                <groupId>org.projectlombok</groupId>
                <artifactId>lombok</artifactId>
                <optional>true</optional>
            </dependency>

**2、编写vm模版**

package ${package}.${moduleName}.entity;
    
    import lombok.Data;
    import lombok.EqualsAndHashCode;
    import lombok.NonNull;
    	#if(${hasBigDecimal})
    import java.math.BigDecimal;
    #end
    import java.io.Serializable;
    import java.time.LocalDateTime;
    
    /**
     * ${comments}
     *
     * @author ${author}
     * @date ${datetime}
     */
    @Data
    @EqualsAndHashCode(callSuper = true)
    public class ${className} {
    	private static final long serialVersionUID = 1L;
    
    #foreach ($property in $properties)
    	/**
    	 * $property.comments
    	 */
    	#if($property.required == true)
    	@NonNull
    	#end
    	private $property.attrType $property.lowerAttrName;
    #end
    }

### 三、逻辑实现 ###

public ResponseEntity<byte[]> genEntity(MultipartFile file, Entity entity) throws IOException {
    
            //设置文件下载请求头
            HttpHeaders headers = new HttpHeaders();
            headers.add("Cache-Control", "no-cache, no-store, must-revalidate");
            headers.add("Content-Disposition", String.format("attachment; filename=\"%s\"",entity.getClassName().concat(".java")));
            headers.add("Pragma", "no-cache");
            headers.add("Expires", "0");
    
            //创建模版实例
            VelocityEngine ve = new VelocityEngine();
            ve.setProperty(RuntimeConstants.RESOURCE_LOADER, "classpath");
            ve.setProperty("classpath.resource.loader.class", ClasspathResourceLoader.class.getName());
            ve.init();
            // 载入（获取）模板对象
            Template t = ve.getTemplate("Entity.java.vm");
            VelocityContext ctx = new VelocityContext();
            // 域对象加入参数值
            ctx.put("author", entity.getAuthor());
            ctx.put("datetime", (new Date()).toLocaleString());
            ctx.put("package", entity.getPackageName());
            ctx.put("moduleName", entity.getModuleName());
            ctx.put("className", entity.getClassName());
            ctx.put("comments", entity.getComments());
            // list集合
            List<Property> temp = new ArrayList<>();
    
            //  BufferedReader br = new BufferedReader(new FileReader(file));
    
            XWPFDocument document = new XWPFDocument(file.getInputStream());
            // 获取所有表格
            int paramName = -1;
            int paramType = -1;
            int paramNeed = -1;
            int paramConmment = -1;
            List<XWPFTable> tables = document.getTables();
            for (XWPFTable table : tables) {
                // 获取表格的行
                List<XWPFTableRow> rows = table.getRows();
    
                //第一行为表格说明
                List<XWPFTableCell> cells = rows.get(0).getTableCells();
                rows.remove(0);
                for (int i = 0; i < cells.size(); i++) {
                    String content = cells.get(i).getText();
                    if (content.matches("(.*字段)|(.*参数)")) {
                        paramName = i;
                    }else if (content.matches(".*类型")) {
                        paramType = i;
                    }else if (content.matches("(.*说明)|(.*描述)|(.*解释)")) {
                        paramConmment = i;
                    }else if (content.matches("是否.*")) {
                        paramNeed = i;
                    }
                }
    
    
                for (XWPFTableRow row : rows) {
                    // 获取表格的每个单元格
                    List<XWPFTableCell> tableCells = row.getTableCells();
    
                    Property p = new Property();
                    //将过长的说明合并为一行
                    if (paramConmment == -1) {
                        p.setComments("");
                    }else {
                        p.setComments(tableCells.get(paramConmment).getText().replaceAll("\\s",""));
                    }
    
                    if (paramType == -1) {
                        p.setAttrType("String");
                    }else  {
                        p.setAttrType(tableCells.get(1).getText());
                    }
                    if (paramName == -1) {
                        return null;
                    }
    
                    p.setLowerAttrName(tableCells.get(0).getText());
    
                    if (paramNeed == -1) {
                        p.setRequired(false);
                    } else {
                        if ("是".equals(tableCells.get(2).getText()) || "true".equals(tableCells.get(2).getText())) {
                            p.setRequired(true);
                        } else {
                            p.setRequired(false);
                        }
                    }
    
                    temp.add(p);
    
                }
            }
    
            //以下为读取txt格式的文档
    /*        String line;
    
            while ((line = br.readLine()) != null) {
                String[] arr = line.split("\\s");
                System.out.println(Arrays.toString(arr));
                Property p = new Property();
                p.setComments(arr[3]);
                p.setAttrType(arr[1]);
                p.setLowerAttrName(arr[0]);
    
                if ("是".equals(arr[2]) || "true".equals(arr[2])) {
                    p.setRequired(true);
                }else {
                    p.setRequired(false);
                }
                temp.add(p);
            }*/
            ctx.put("properties", temp);
    
            StringWriter sw = new StringWriter();
            t.merge(ctx, sw);
    
            System.out.println(sw.toString());
    
            return ResponseEntity.ok().headers(headers)
                    .contentLength(sw.toString().getBytes().length).contentType(MediaType.parseMediaType
                            ("application/octet-stream"))
                    .body(sw.toString().getBytes());
        }

### 四、测试  ###

**1、准备docx文档数据**

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzM1ODEzNjUz_size_16_color_FFFFFF_t_70][]

**2、填充表格参数**

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzM1ODEzNjUz_size_16_color_FFFFFF_t_70 1][]

**3、获取实体类**

![watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzM1ODEzNjUz_size_16_color_FFFFFF_t_70 2][]

### 五、资源 ###

**1、测试路径**：[http://106.12.121.80:8080/][http_106.12.121.80_8080]

**2、项目下载：**[传送门][Link 1]

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[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzM1ODEzNjUz_size_16_color_FFFFFF_t_70 1]: /images/20220411/142d745f035543808b15c076a815c7ff.png
[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzM1ODEzNjUz_size_16_color_FFFFFF_t_70 2]: /images/20220411/a1a9a55a7ade432c9a1530d359eeb456.png
[http_106.12.121.80_8080]: http://106.12.121.80:8080/
[Link 1]: https://download.csdn.net/download/qq_35813653/10829641