From b8c07682b959b43ec00241fded7c02efa6bc92e9 Mon Sep 17 00:00:00 2001
From: yangzhe123 <2824096059@qq.com>
Date: Thu, 4 Sep 2025 10:45:11 +0800
Subject: [PATCH] =?UTF-8?q?=E6=96=B0=E5=A2=9Epdf=E9=A1=B5=E7=A0=81?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 .../hsz/service/ForecastProjectService.java   | 217 ++++++++++++------
 1 file changed, 151 insertions(+), 66 deletions(-)

diff --git a/src/main/java/com/gunshi/project/hsz/service/ForecastProjectService.java b/src/main/java/com/gunshi/project/hsz/service/ForecastProjectService.java
index 599e397..b53abe7 100644
--- a/src/main/java/com/gunshi/project/hsz/service/ForecastProjectService.java
+++ b/src/main/java/com/gunshi/project/hsz/service/ForecastProjectService.java
@@ -7,6 +7,7 @@ import com.gunshi.project.hsz.mapper.ForecastProjectMapper;
 import com.gunshi.project.hsz.model.ForecastProject;
 import com.gunshi.project.hsz.model.ForecastResults;
 import com.itextpdf.io.font.PdfEncodings;
+import com.itextpdf.kernel.colors.Color;
 import com.itextpdf.kernel.colors.DeviceRgb;
 import com.itextpdf.kernel.events.Event;
 import com.itextpdf.kernel.events.IEventHandler;
@@ -19,6 +20,7 @@ import com.itextpdf.kernel.pdf.PdfDocument;
 import com.itextpdf.kernel.pdf.PdfPage;
 import com.itextpdf.kernel.pdf.PdfWriter;
 import com.itextpdf.kernel.pdf.canvas.PdfCanvas;
+import com.itextpdf.kernel.pdf.colorspace.PdfColorSpace;
 import com.itextpdf.layout.Canvas;
 import com.itextpdf.layout.Document;
 import com.itextpdf.layout.element.Cell;
@@ -32,6 +34,7 @@ import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.stereotype.Service;
 import org.springframework.transaction.annotation.Transactional;
 
+import java.awt.*;
 import java.io.ByteArrayOutputStream;
 import java.io.IOException;
 import java.math.BigDecimal;
@@ -92,93 +95,175 @@ public class ForecastProjectService extends ServiceImpl<ForecastProjectMapper, F
     }
 
     public void generatePdf(ForecastProject project, ZipOutputStream outputStream) {
+        // 第一次生成：获取总页码
+        int totalPages = calculateTotalPages(project);
 
-        // 使用ByteArrayOutputStream作为缓冲
+        // 第二次生成：正式生成带页码的PDF
+        generatePdfWithPageNumbers(project, outputStream, totalPages);
+    }
+
+    // 第一次生成：计算总页码
+    private int calculateTotalPages(ForecastProject project) {
         ByteArrayOutputStream baos = new ByteArrayOutputStream();
-        PdfDocument pdfDoc = null;
-        Document document = null;
-        try{
-            PdfWriter writer = new  PdfWriter(baos);
-            pdfDoc = new PdfDocument(writer);
-            document = new Document(pdfDoc,PageSize.A4.rotate());
-                // 设置字体
-                String fontPath = "/fonts/ChineseFonts.ttf";
-                PdfFont font = PdfFontFactory.createFont(fontPath, PdfEncodings.IDENTITY_H);
-                // 第一行：基本信息
-                Paragraph header1 = new Paragraph()
-                        .add("预见期(小时): " + (project.getForecastPeriod() != null ? project.getForecastPeriod() : "无") + "    ")
-                        .add("预热期(天): " + (project.getForecastWarm() != null ? project.getForecastWarm() : "无") + "    ")
-                        .add("预报时间: " + formatDate(project.getForecastTm()) + "    ")
-                        .add("开始时间: " + formatDate(project.getStartTm()) + "    ")
-                        .add("结束时间: " + formatDate(project.getEndTm()))
-                        .setFont(font)
-                        .setFontSize(10);
 
-                document.add(header1);
-                document.add(new Paragraph("\n"));
+        try (PdfWriter writer = new PdfWriter(baos);
+             PdfDocument pdfDoc = new PdfDocument(writer);
+             Document document = new Document(pdfDoc, PageSize.A4.rotate())) {
 
-                // 第二行：统计信息
-                Paragraph header2 = new Paragraph()
-                        .add("预报最高调洪水位(m): " + (project.getYcMaxSwH() != null ? project.getYcMaxSwH().setScale(2, RoundingMode.HALF_UP) : "无") + "    ")
-                        .add("预报最大入库流量(m³/s): " + (project.getYcMaxRkQ() != null ? project.getYcMaxRkQ().setScale(2, RoundingMode.HALF_UP) : "无") + "    ")
-                        .add("预报最大下泄流量(m³/s): " + (project.getYcMaxCkQ() != null ? project.getYcMaxCkQ().setScale(2, RoundingMode.HALF_UP) : "无") + "    ")
-                        .add("预报洪水总量(万m³): " + (project.getYcSumFlood() != null ? project.getYcSumFlood().setScale(2, RoundingMode.HALF_UP) : "无"))
-                        .setFont(font)
-                        .setFontSize(10);
+            // 设置字体
+            String fontPath = "/fonts/ChineseFonts.ttf";
+            PdfFont font = PdfFontFactory.createFont(fontPath, PdfEncodings.IDENTITY_H);
 
-                document.add(header2);
-                document.add(new Paragraph("\n"));
+            // 添加内容（但不添加页码）
+            addContentToDocument(document, font, project, false);
 
-                // 第三行：数据表格
-                if (CollectionUtils.isNotEmpty(project.getVoList())) {
-                    Table table = new Table(9); // 10列
-                    table.setWidth(UnitValue.createPercentValue(100));
+            // 返回总页数
+            return pdfDoc.getNumberOfPages();
 
-                    // 表头
-                    table.addHeaderCell(createCell("序号", font, true));
-                    table.addHeaderCell(createCell("时间", font, true));
-                    table.addHeaderCell(createCell("降雨量(mm)", font, true));
-                    table.addHeaderCell(createCell("实测水位(m)", font, true));
-                    table.addHeaderCell(createCell("预报水位(m)", font, true));
-                    table.addHeaderCell(createCell("入库流量(m³/s)", font, true));
-                    table.addHeaderCell(createCell("预报入库流量(m³/s)", font, true));
-                    table.addHeaderCell(createCell("实际出库流量(m³/s)", font, true));
-                    table.addHeaderCell(createCell("预报出库流量(m³/s)", font, true));
+        } catch (Exception e) {
+            log.error("计算PDF页数失败", e);
+            throw new RuntimeException("PDF页数计算失败");
+        }
+    }
+
+    // 第二次生成：正式生成带页码的PDF
+    private void generatePdfWithPageNumbers(ForecastProject project, ZipOutputStream outputStream, int totalPages) {
+        ByteArrayOutputStream baos = new ByteArrayOutputStream();
+
+        try (PdfWriter writer = new PdfWriter(baos);
+             PdfDocument pdfDoc = new PdfDocument(writer);
+             Document document = new Document(pdfDoc, PageSize.A4.rotate())) {
+
+            // 设置字体
+            String fontPath = "/fonts/ChineseFonts.ttf";
+            PdfFont font = PdfFontFactory.createFont(fontPath, PdfEncodings.IDENTITY_H);
+
+            // 添加页码处理器
+            PageNumberEventHandler eventHandler = new PageNumberEventHandler(font, totalPages);
+            pdfDoc.addEventHandler(PdfDocumentEvent.END_PAGE, eventHandler);
+
+            // 添加内容
+            addContentToDocument(document, font, project, true);
 
-                    // 表格数据
-                    int index = 1;
-                    for (ForecastResultVo vo : project.getVoList()) {
-                        table.addCell(createCell(String.valueOf(index++), font, false));
-                        table.addCell(createCell(vo.getTm(), font, false));
-                        table.addCell(createCell(formatBigDecimal(vo.getDrp()), font, false));
-                        table.addCell(createCell(formatBigDecimal(vo.getRealSwHValue()), font, false));
-                        table.addCell(createCell(formatBigDecimal(vo.getYcSwHValue()), font, false));
-                        table.addCell(createCell(formatBigDecimal(vo.getRealRkQValue()), font, false));
-                        table.addCell(createCell(formatBigDecimal(vo.getYcRkQValue()), font, false));
-                        table.addCell(createCell(formatBigDecimal(vo.getRealCkQValue()), font, false));
-                        table.addCell(createCell(formatBigDecimal(vo.getYcCkQValue()), font, false));
-                    }
-                    document.add(table);
-                } else {
-                    document.add(new Paragraph("无预报结果数据").setFont(font));
-                }
-                // 5. 关闭文档（关键：先关闭Document，再关闭PdfDocument）
-                document.close();
-                pdfDoc.close();
         } catch (Exception e) {
             log.error("生成PDF失败", e);
             throw new RuntimeException("PDF生成失败");
         }
 
+        // 在try-with-resources块外获取字节数组并写入输出流
         try {
             byte[] pdfBytes = baos.toByteArray();
             outputStream.write(pdfBytes);
-        }catch (IOException e){
+        } catch (IOException e) {
             log.error("写入ZIP失败", e);
             throw new RuntimeException("写入ZIP失败");
         }
     }
 
+    // 页码事件处理器 - 简化版本
+    private static class PageNumberEventHandler implements IEventHandler {
+        private final PdfFont font;
+        private final int totalPages;
+
+        public PageNumberEventHandler(PdfFont font, int totalPages) {
+            this.font = font;
+            this.totalPages = totalPages;
+        }
+
+        @Override
+        public void handleEvent(Event event) {
+            PdfDocumentEvent docEvent = (PdfDocumentEvent) event;
+            PdfDocument pdfDoc = docEvent.getDocument();
+            PdfPage page = docEvent.getPage();
+            int currentPage = pdfDoc.getPageNumber(page);
+
+            // 获取页面尺寸
+            Rectangle pageSize = page.getPageSize();
+
+            // 创建画布
+            PdfCanvas pdfCanvas = new PdfCanvas(page.newContentStreamAfter(), page.getResources(), pdfDoc);
+
+            // 设置页码文本
+            String pageText = "第 " + currentPage + " 页 / 共 " + totalPages + " 页";
+
+            // 直接使用PdfCanvas绘制文本（更简单的方式）
+            pdfCanvas.beginText()
+                    .setFontAndSize(font, 10)
+                    .moveText((pageSize.getLeft() + pageSize.getRight()) / 2 - 50, pageSize.getBottom() + 20)
+                    .showText(pageText)
+                    .endText();
+
+            pdfCanvas.release();
+        }
+    }
+
+    // 添加内容到文档的公共方法
+    private void addContentToDocument(Document document, PdfFont font, ForecastProject project, boolean addPageMargins) throws IOException {
+        if (addPageMargins) {
+            // 为页码预留底部边距
+            document.setMargins(36, 36, 36, 50);
+        }
+
+        // 第一行：基本信息
+        Paragraph header1 = new Paragraph()
+                .add("预见期(小时): " + (project.getForecastPeriod() != null ? project.getForecastPeriod() : "无") + "    ")
+                .add("预热期(天): " + (project.getForecastWarm() != null ? project.getForecastWarm() : "无") + "    ")
+                .add("预报时间: " + formatDate(project.getForecastTm()) + "    ")
+                .add("开始时间: " + formatDate(project.getStartTm()) + "    ")
+                .add("结束时间: " + formatDate(project.getEndTm()))
+                .setFont(font)
+                .setFontSize(10);
+
+        document.add(header1);
+        document.add(new Paragraph("\n"));
+
+        // 第二行：统计信息
+        Paragraph header2 = new Paragraph()
+                .add("预报最高调洪水位(m): " + (project.getYcMaxSwH() != null ? project.getYcMaxSwH().setScale(2, RoundingMode.HALF_UP) : "无") + "    ")
+                .add("预报最大入库流量(m³/s): " + (project.getYcMaxRkQ() != null ? project.getYcMaxRkQ().setScale(2, RoundingMode.HALF_UP) : "无") + "    ")
+                .add("预报最大下泄流量(m³/s): " + (project.getYcMaxCkQ() != null ? project.getYcMaxCkQ().setScale(2, RoundingMode.HALF_UP) : "无") + "    ")
+                .add("预报洪水总量(万m³): " + (project.getYcSumFlood() != null ? project.getYcSumFlood().setScale(2, RoundingMode.HALF_UP) : "无"))
+                .setFont(font)
+                .setFontSize(10);
+
+        document.add(header2);
+        document.add(new Paragraph("\n"));
+
+        // 第三行：数据表格
+        if (CollectionUtils.isNotEmpty(project.getVoList())) {
+            Table table = new Table(9);
+            table.setWidth(UnitValue.createPercentValue(100));
+
+            // 表头
+            table.addHeaderCell(createCell("序号", font, true));
+            table.addHeaderCell(createCell("时间", font, true));
+            table.addHeaderCell(createCell("降雨量(mm)", font, true));
+            table.addHeaderCell(createCell("实测水位(m)", font, true));
+            table.addHeaderCell(createCell("预报水位(m)", font, true));
+            table.addHeaderCell(createCell("入库流量(m³/s)", font, true));
+            table.addHeaderCell(createCell("预报入库流量(m³/s)", font, true));
+            table.addHeaderCell(createCell("实际出库流量(m³/s)", font, true));
+            table.addHeaderCell(createCell("预报出库流量(m³/s)", font, true));
+
+            // 表格数据
+            int index = 1;
+            for (ForecastResultVo vo : project.getVoList()) {
+                table.addCell(createCell(String.valueOf(index++), font, false));
+                table.addCell(createCell(vo.getTm(), font, false));
+                table.addCell(createCell(formatBigDecimal(vo.getDrp()), font, false));
+                table.addCell(createCell(formatBigDecimal(vo.getRealSwHValue()), font, false));
+                table.addCell(createCell(formatBigDecimal(vo.getYcSwHValue()), font, false));
+                table.addCell(createCell(formatBigDecimal(vo.getRealRkQValue()), font, false));
+                table.addCell(createCell(formatBigDecimal(vo.getYcRkQValue()), font, false));
+                table.addCell(createCell(formatBigDecimal(vo.getRealCkQValue()), font, false));
+                table.addCell(createCell(formatBigDecimal(vo.getYcCkQValue()), font, false));
+            }
+            document.add(table);
+        } else {
+            document.add(new Paragraph("无预报结果数据").setFont(font));
+        }
+    }
+
     // 辅助方法：创建表格单元格
     private Cell createCell(String text, PdfFont font, boolean isHeader) {
         Cell cell = new Cell().add(new Paragraph(text).setFont(font).setFontSize(8));