Java读写pdf文件

╰半夏微凉° 2024-03-16 19:32 48阅读 0赞

## Java读写pdf文件 ##

在OA业务开发中，经常需要java后台读取或生成pdf文件，
    itextpdf是一个常用的java操作pdf的开源库

物料准备：  
1.引入itextpdf依赖  
2.定义Text2PdfUtil工具类

### 引入itextpdf相关的依赖 ###

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

### 定义工具类Text2PdfUtil.java ###

package cn.ath.knowwikibackend.util;
    
    import com.itextpdf.text.Document;
    import com.itextpdf.text.DocumentException;
    import com.itextpdf.text.Font;
    import com.itextpdf.text.Paragraph;
    import com.itextpdf.text.pdf.BaseFont;
    import com.itextpdf.text.pdf.PdfReader;
    import com.itextpdf.text.pdf.PdfWriter;
    import com.itextpdf.text.pdf.parser.PdfTextExtractor;
    
    import java.io.*;
    import java.nio.charset.Charset;
    
    /**
     * 需要引入的依赖
     *
     * <dependency>
     *             <groupId>com.itextpdf</groupId>
     *             <artifactId>itext-asian</artifactId>
     *             <version>5.2.0</version>
     *         </dependency>
     *
     *         <dependency>
     *             <groupId>com.itextpdf</groupId>
     *             <artifactId>itextpdf</artifactId>
     *             <version>5.5.13</version>
     *         </dependency>
     *
     */
    public class Text2PdfUtil {
        
    
        /**
         * txt文本文件  转pdf文件
         * @param text   F:/data/te616.txt
         * @param pdf  F:/data/aet618.pdf
         * @throws DocumentException
         * @throws IOException
         */
        public static void text2pdf(String text,String pdf) throws DocumentException, IOException {
        
            Document doc = new Document();
            OutputStream os = new FileOutputStream(new File(pdf));
            PdfWriter.getInstance(doc, os);
            doc.open();
            //指定 使用内置的中文字体
            BaseFont baseFont =
                    BaseFont.createFont("STSong-Light", "UniGB-UCS2-H", BaseFont.EMBEDDED);
            Font font = new Font(baseFont,12,Font.NORMAL);
            //指定输出编码为UTF-8
            InputStreamReader isr = new InputStreamReader(
                    new FileInputStream(new File(text)), Charset.forName("UTF-8"));
            BufferedReader br = new BufferedReader(isr);
            String str = "";
            while((str = br.readLine()) != null){
        
                doc.add(new Paragraph(str,font));
            }
            isr.close();
            br.close();
            doc.close();
        }
    
    
        /**
         * 读取pdf文件的内容
         * @param filename  F:/data/aet618.pdf
         * @return  String
         */
        public static String readPDF(String filename){
        
            StringBuilder result = new StringBuilder();
            try {
        
                PdfReader reader = new PdfReader(filename);
                int countPage = reader.getNumberOfPages();
                for(int i=1;i<=countPage;i++){
        
                    result.append(PdfTextExtractor.getTextFromPage(reader, i));
                }
                reader.close();
            } catch (IOException e) {
        
                e.printStackTrace();
            }
            return result.toString();
        }
    
    }

### 测试 ###

@Test
        void contextLoads() throws DocumentException, IOException {
        
            String txtPath = "E:/test617.txt";
            String pdfPath = "E:/test617.pdf";
            Text2PdfUtil.text2pdf(txtPath,pdfPath);
            System.out.println(Text2PdfUtil.readPDF(pdfPath));
        }

![在这里插入图片描述][048de81a6e8e4cb492e3d2ff60e6c965.png_pic_center]  
![在这里插入图片描述][2acca9608d9b4dada7a7d28dba2278fd.png_pic_center]

[048de81a6e8e4cb492e3d2ff60e6c965.png_pic_center]: https://image.dandelioncloud.cn/pgy_files/images/2024/03/15/fa49e5f00d9840e0b7bbfbac83d04beb.png
[2acca9608d9b4dada7a7d28dba2278fd.png_pic_center]: https://image.dandelioncloud.cn/pgy_files/images/2024/03/15/0c9a0f5d6bb743638f062f248a4c45eb.png