pdf导出工具类

（目前只更新导出pdf表格）

导出pdf表格

1、依赖：

<dependency>
	<groupId>com.itextpdf</groupId>
	<artifactId>itextpdf</artifactId>
	<version>5.5.13</version>
</dependency>
<dependency>
	<groupId>com.itextpdf</groupId>
	<artifactId>itext-asian</artifactId>
	<version>5.2.0</version>
</dependency>

2、工具类：

import com.crunii.micro.common.exception.BusinessException;
import com.itextpdf.text.*;
import com.itextpdf.text.pdf.BaseFont;
import com.itextpdf.text.pdf.PdfPCell;
import com.itextpdf.text.pdf.PdfPTable;
import com.itextpdf.text.pdf.PdfWriter;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletResponse;
import java.lang.reflect.Field;
import java.net.URLEncoder;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;
import java.util.Map;

/** * @Filename: PdfUtils * @Author: sheng.wanping * <li>Date: 2022/8/1 15:40</li> * <li>Version: 1.0</li> * <li>Content: create</li> */
public class PdfUtils {
    

	// 定义全局的字体静态变量
	private static Font titlefont;
	private static Font textfont;
	static {
    
	   try {
    
	       BaseFont bfChinese = BaseFont.createFont("STSong-Light", "UniGB-UCS2-H", BaseFont.NOT_EMBEDDED);
	       titlefont = new Font(bfChinese, 8, Font.BOLD);
	       textfont = new Font(bfChinese, 8, Font.NORMAL);
	   } catch (Exception e) {
    
	       e.printStackTrace();
	   }
	}

    /** * 用于返回 简单列表ftp表格 * @param response * @param tableName 表名 * @param list 数据列表 * @param map 中英文map(key为标题，value为字段英文名；注意：map是有顺序的，可用LinkedHashMap) * @param <T> */
    public static  <T> void pdfSingleTable(HttpServletResponse response, String tableName, List<T> list, Map<String, String> map) {
    
        // 1、从map中获取字段中文名和英文名
        List<String> valueList = new ArrayList<>(); // 存表格所有数据
        List<String> fieldEnList = new ArrayList<>(); // 字段英文名
        for (Map.Entry<String, String> entry : map.entrySet()) {
    
            valueList.add(entry.getKey());
            fieldEnList.add(entry.getValue());
        }
        // 2、用反射根据字段名获取值
        for (int i = 0; i < list.size(); i++) {
    
            for (int j = 0; j < fieldEnList.size(); j++) {
    
                Field field = null;
                String strValue = "";
                try {
    
                    field = list.get(i).getClass().getDeclaredField(fieldEnList.get(j));
                    field.setAccessible(true);
                    Object value = field.get(list.get(i));
                    if (value != null) {
    
                        if (value instanceof Date) {
    
                            strValue = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss").format(value);
                        } else {
    
                            strValue = String.valueOf(value);
                        }
                    } else {
    
                        strValue = "";
                    }
                } catch (NoSuchFieldException e) {
    
                    e.printStackTrace();
                } catch (IllegalAccessException e) {
    
                    e.printStackTrace();
                } finally {
    
                    valueList.add(strValue);// 字段值
                }
            }
        }
        // 3、返回pdf
        try {
    
            // 3-1.新建document对象
            Document document = new Document(PageSize.A4);
            // 3-2.建立一个书写器
            response.setHeader("Content-Type", "application/pdf");
            response.setHeader("Content-Disposition", "attachment;filename=" + URLEncoder.encode(tableName + ".pdf", "UTF-8"));
            ServletOutputStream out = response.getOutputStream();
            PdfWriter.getInstance(document, out);
            // 3-3.打开文档
            document.open();
            // 3-4、查询数据库数据，并存入list中
            // 3-5、设置单元格宽度
            List<Integer> mergeCellList = new ArrayList<>();
            int idx = 0;
            while (idx < (list.size() + 1) * fieldEnList.size()) {
    
                idx++;
                mergeCellList.add(1);
            }
            // 3-6.创建表格
            PdfPTable table = new PdfPTable(fieldEnList.size());
            for (int i = 0; i < mergeCellList.size(); i++) {
    
                PdfPCell cell = new PdfPCell(); // 创建行
                cell.setColspan(mergeCellList.get(i)); // 合并单元格
                // 如果有合并行可以这样写 cell.setRowspan(2)
                cell.setPhrase(new Phrase(valueList.get(i), textfont));
                cell.setHorizontalAlignment(Element.ALIGN_CENTER);//水平居中
                cell.setVerticalAlignment(Element.ALIGN_MIDDLE); //垂直居中
                table.addCell(cell); // 添加单元格内容
            }
            // 3-7、向文档中添加内容
            document.add(table);
            // 3-8、关闭文档
            document.close();
            out.close();
        }catch (Exception e){
    
            e.printStackTrace();
            throw new BusinessException("导出pdf失败");
        }
    }

}

3、测试代码

	private static final Map<String, String> BUDGE_MAP = new LinkedHashMap<>();
	static {
    
	   BUDGE_MAP.put("主设备", "mainEquipmentExpense");
	   BUDGE_MAP.put("天线", "aerialExpense");
	   BUDGE_MAP.put("电源", "powerExpense");
	}
	
	public void testPdf(HttpServletResponse response) {
    
        List<Object> list = testDao.getData;// 查询数据列表
        PdfUtils.pdfSingleTable(response, "表名", list, BUDGE_MAP);// 导出pdf表格
    }