使用JAVA搜索和替换PDF中的文本 [英] Search and replace text in PDF using JAVA

问题描述

需要用其他语言替换pdf中的文本.第一步，我尝试使用itextpdf ad pdfbox API搜索和替换pdf文件中的文本.

Need to replace the text in the pdf with different language. In the first step, I was trying to search and replace a text in the pdf file using itextpdf ad pdfbox API.

使用下面的代码片段，该片段使用itextpdf api从源PDF文件中搜索并将文本"Hello"替换为"Hi".创建新的PDF时不会替换任何文本.

Use the below code snippet which uses itextpdf api to search and replace the text "Hello" to "Hi" from the source PDF file. The new PDF is created without any text replacements.

public void manipulatePdf(String src, String dest) throws Exception {
    PdfDocument pdfDoc = new PdfDocument(new PdfReader(SRC), new PdfWriter(DEST));
    int noOfPages = pdfDoc.getNumberOfPages();
    for (int i = 1; i < noOfPages; i++) {
        PdfPage page = pdfDoc.getPage(i);
        PdfDictionary dict = page.getPdfObject();
        PdfObject object = dict.get(PdfName.Contents);
        if (object instanceof PdfStream) {
            PdfStream stream = (PdfStream) object;
            byte[] data = stream.getBytes();
            stream.setData(new String(data).replace("Hello", "Hi").getBytes("UTF-8"));
        }
    }
    pdfDoc.close();
}

还使用apache pdfbox实现了相同的功能，但是没有运气.以下是供参考的代码段.

Also used apache pdfbox to achieve the same thing but no luck in that. Below is the code snippet for the reference.

    public static PDDocument replaceText(PDDocument document, String searchString, String replacement)
        throws IOException {        
    for (PDPage page : document.getPages()) {
        PDFStreamParser parser = new PDFStreamParser(page);
        parser.parse();
        List tokens = parser.getTokens();
        for (int j = 0; j < tokens.size(); j++) {
            Object next = tokens.get(j);
            if (next instanceof Operator) {
                Operator op = (Operator) next;
                // Tj and TJ are the two operators that display strings in a PDF
                if (op.getName().equals("Tj")) {
                    // Tj takes one operator and that is the string to display
                    // so lets update that operator
                    COSString previous = (COSString) tokens.get(j - 1);
                    String string = previous.getString();
                    //System.out.println(new String(string.getBytes(StandardCharsets.UTF_8), StandardCharsets.UTF_8));
                    string = string.replaceFirst(searchString, replacement);
                    previous.setValue(string.getBytes());

                } else if (op.getName().equals("TJ")) {
                    COSArray previous = (COSArray) tokens.get(j - 1);
                    for (int k = 0; k < previous.size(); k++) {
                        Object arrElement = previous.getObject(k);
                        if (arrElement instanceof COSString) {
                            COSString cosString = (COSString) arrElement;
                            String string = cosString.getString();
                            //System.out.println("22::"+new String(string.getBytes(StandardCharsets.UTF_8), StandardCharsets.UTF_8));
                            string = StringUtils.replaceOnce(string, searchString, replacement);
                            cosString.setValue(string.getBytes());
                        }
                    }
                }
            }
        }

        PDStream updatedStream = new PDStream(document);
        OutputStream out = updatedStream.createOutputStream(COSName.FLATE_DECODE);
        ContentStreamWriter tokenWriter = new ContentStreamWriter(out);
        tokenWriter.writeTokens(tokens);
         // save content
        page.setContents(updatedStream);
        out.close();
    }

高度赞赏任何解决方案/建议.

Any solution/suggestion is highly appreciated.

推荐答案

这是一个有效的版本，使用PDFBox

This is a working version, uses PDFBox

import java.io.File;
import java.io.IOException;
import java.io.OutputStream;
import java.util.List;

import org.apache.commons.lang3.StringUtils;
import org.apache.pdfbox.contentstream.operator.Operator;
import org.apache.pdfbox.cos.COSArray;
import org.apache.pdfbox.cos.COSName;
import org.apache.pdfbox.cos.COSString;
import org.apache.pdfbox.pdfparser.PDFStreamParser;
import org.apache.pdfbox.pdfwriter.ContentStreamWriter;
import org.apache.pdfbox.pdmodel.PDDocument;
import org.apache.pdfbox.pdmodel.PDPage;
import org.apache.pdfbox.pdmodel.common.PDStream;

public final class PDFEditor {

    private PDFEditor() {
    }

    public static void main(String[] args) throws IOException {
        PDDocument document = null;
        document = PDDocument.load(new File("src path"));
        document = replaceText(document, "Hello", "Hi");
        document.save("target Path");
        document.close();
    }

    private static PDDocument replaceText(PDDocument document, String searchString, String replacement) throws IOException {
        if (StringUtils.isEmpty(searchString) || StringUtils.isEmpty(replacement)) {
            return document;
        }

        for (PDPage page : document.getPages()) {
            PDFStreamParser parser = new PDFStreamParser(page);
            parser.parse();
            List<?> tokens = parser.getTokens();

            for (int j = 0; j < tokens.size(); j++) {
                Object next = tokens.get(j);
                if (next instanceof Operator) {
                    Operator op = (Operator) next;

                    String pstring = "";
                    int prej = 0;

                    if (op.getName().equals("Tj")) {
                        COSString previous = (COSString) tokens.get(j - 1);
                        String string = previous.getString();
                        string = string.replaceFirst(searchString, replacement);
                        previous.setValue(string.getBytes());
                    } else if (op.getName().equals("TJ")) {
                        COSArray previous = (COSArray) tokens.get(j - 1);
                        for (int k = 0; k < previous.size(); k++) {
                            Object arrElement = previous.getObject(k);
                            if (arrElement instanceof COSString) {
                                COSString cosString = (COSString) arrElement;
                                String string = cosString.getString();

                                if (j == prej) {
                                    pstring += string;
                                } else {
                                    prej = j;
                                    pstring = string;
                                }
                            }
                        }

                        if (searchString.equals(pstring.trim())) {
                            COSString cosString2 = (COSString) previous.getObject(0);
                            cosString2.setValue(replacement.getBytes());

                            int total = previous.size() - 1;
                            for (int k = total; k > 0; k--) {
                                previous.remove(k);
                            }
                        }
                    }
                }
            }
            PDStream updatedStream = new PDStream(document);
            OutputStream out = updatedStream.createOutputStream(COSName.FLATE_DECODE);
            ContentStreamWriter tokenWriter = new ContentStreamWriter(out);
            tokenWriter.writeTokens(tokens);
            out.close();
            page.setContents(updatedStream);
        }

        return document;
    }

}

依赖项:

<dependency>
    <groupId>com.itextpdf</groupId>
    <artifactId>itextpdf</artifactId>
    <version>5.0.6</version>
</dependency>
        <!-- https://mvnrepository.com/artifact/org.apache.pdfbox/pdfbox -->
<dependency>
    <groupId>org.apache.pdfbox</groupId>
    <artifactId>pdfbox</artifactId>
    <version>2.0.11</version>
</dependency>
<!-- https://mvnrepository.com/artifact/org.apache.commons/commons-lang3 -->
<dependency>
    <groupId>org.apache.commons</groupId>
    <artifactId>commons-lang3</artifactId>
    <version>3.0</version>
</dependency>

这篇关于使用JAVA搜索和替换PDF中的文本的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！