Merge remote-tracking branch 'origin/dev_v2.2.2' into dev_v2.2.2

distributed-print-business/src/main/java/com/qmth/distributed/print/business/util/PdfUtil.java

@@ -10,14 +10,12 @@ import com.qmth.teachcloud.common.enums.ExceptionResultEnum;
 import com.qmth.teachcloud.common.enums.PageSizeEnum;
 import com.qmth.teachcloud.common.enums.UploadFileEnum;
 import com.qmth.teachcloud.common.util.JacksonUtil;
+import com.sun.org.apache.bcel.internal.generic.GOTO;
 import org.apache.commons.io.IOUtils;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
-import java.io.ByteArrayOutputStream;
-import java.io.File;
-import java.io.FileOutputStream;
-import java.io.IOException;
+import java.io.*;
 import java.time.LocalDateTime;
 import java.util.Objects;
 import java.util.Optional;
@@ -159,10 +157,24 @@ public class PdfUtil {
      * @throws IOException
      */
     public static PageSizeEnum getPdfFormat(File file) throws IOException {
+
+
         Optional.ofNullable(file).orElseThrow(() -> ExceptionResultEnum.ERROR.exception("文件不能为空"));
         PdfReader reader = new PdfReader(ByteArray.fromFile(file).value());
-        Rectangle pageSize = reader.getPageSize(1);
-        return PageSizeEnum.convertToEnum(pageSize.getWidth(), pageSize.getHeight());
+        int totalPages = reader.getNumberOfPages();
+        PageSizeEnum pageSizeEnum = null;
+        for (int i = 1;i < totalPages;i ++){
+            Rectangle pageSize = reader.getPageSize(i);
+            if (pageSizeEnum != null){
+                if (!pageSizeEnum.equals(PageSizeEnum.convertToEnum(pageSize.getWidth(), pageSize.getHeight()))){
+                    throw ExceptionResultEnum.ERROR.exception("上传的试卷pdf中存在纸张格式不一样的");
+                }
+            }else {
+                pageSizeEnum = PageSizeEnum.convertToEnum(pageSize.getWidth(), pageSize.getHeight());
+            }
+        }
+
+        return pageSizeEnum;
     }
 
 //    public static void main(String[] args) {
@@ -175,4 +187,77 @@ public class PdfUtil {
 //        String outputPath = "/Users/king/Downloads/pdf/merge1.pdf";
 //        PdfUtil.mergePdf(files, outputPath);
 //    }
+
+    /**
+     * 两页打印到一页（A4 -> A3）
+     * @param streamOfPDFFile 原卷
+     * @param outputStream 输出的试卷
+     * @param paginate 是否生成A3 每页页码
+     */
+    public static void concatPDFs(InputStream streamOfPDFFile, OutputStream outputStream, boolean paginate) {
+
+        Document document = new Document();
+        try {
+
+            //读取PDF
+            InputStream pdf = streamOfPDFFile;
+            PdfReader pdfReader = new PdfReader(pdf);
+            int totalPages = pdfReader.getNumberOfPages();
+
+            //创建PDF Writer
+            PdfWriter writer = PdfWriter.getInstance(document, outputStream);
+            document.open();
+            BaseFont baseFont = BaseFont.createFont(BaseFont.HELVETICA, BaseFont.CP1252, BaseFont.NOT_EMBEDDED);
+            PdfContentByte contentByte = writer.getDirectContent();
+
+            Rectangle rec = pdfReader.getPageSize(1);
+            //新pdf为两个宽度
+            Rectangle newRec = new Rectangle(0, 0, rec.getWidth() * 2, rec.getHeight());
+            document.setPageSize(newRec);
+
+            PdfImportedPage page;
+            PdfImportedPage page2;
+            int currentPageNumber = 0;
+
+            //舍弃奇数的最后一页, 删除该设置后面不受影响
+//            totalPages = totalPages >> 1 << 1;
+            for (int pageIndex = 0; pageIndex < totalPages; pageIndex += 2) {
+                document.newPage();
+                currentPageNumber++;
+
+                //原始第一页设置到左边
+                page = writer.getImportedPage(pdfReader, pageIndex + 1);
+                contentByte.addTemplate(page, 0, 0);
+
+                //第二页设置到右边
+                if (pageIndex + 2 <= totalPages) {
+                    page2 = writer.getImportedPage(pdfReader, pageIndex + 2);
+                    contentByte.addTemplate(page2, rec.getWidth(), 0);
+                }
+
+                //设置页码
+                if (paginate) {
+                    contentByte.beginText();
+                    contentByte.setFontAndSize(baseFont, 13);
+                    contentByte.showTextAligned(PdfContentByte.ALIGN_CENTER, "" + currentPageNumber + "/" + (totalPages / 2 + (totalPages % 2 == 0 ? 0 : 1)), newRec.getWidth() / 2, 17, 0);
+                    contentByte.endText();
+                }
+            }
+
+            outputStream.flush();
+            document.close();
+            outputStream.close();
+        } catch (Exception e) {
+            e.printStackTrace();
+        } finally {
+            if (document.isOpen())
+                document.close();
+            try {
+                if (outputStream != null)
+                    outputStream.close();
+            } catch (IOException ioe) {
+                ioe.printStackTrace();
+            }
+        }
+    }
 }