如何使用iText读写pdf呢?

实现思路:
    1.引入iText依赖
	2.生成pdf实例
	3.借助 PdfWriter和PdfReader
	  编写相应的代码

pom.xml

<dependency>
            <groupId>com.itextpdf</groupId>
            <artifactId>itextpdf</artifactId>
            <version>5.5.10</version>
        </dependency>

iText编写PDF
  使用iText PdfWriter将内容写入PDF文件

package com.java265;
 
import com.itextpdf.text.*;
import com.itextpdf.text.pdf.PdfWriter;
 
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
 
public class PdfWriteExample {
 
    private static final String FILE_NAME = "/tmp/itext.pdf";
 
    public static void main(String[] args) {
        writeUsingIText();
    }
 
    private static void writeUsingIText() {
 
        Document document = new Document();
 
        try {
 
            PdfWriter.getInstance(document, new FileOutputStream(new File(FILE_NAME)));
 
            //open
            document.open();
 
            Paragraph p = new Paragraph();
            p.add("This is my paragraph 1");
            p.setAlignment(Element.ALIGN_CENTER);
 
            document.add(p);
 
            Paragraph p2 = new Paragraph();
            p2.add("Java265是我最喜欢的学习网站"); //no alignment
 
            document.add(p2);
 
            Font f = new Font();
            f.setStyle(Font.BOLD);
            f.setSize(8);
 
            document.add(new Paragraph("我爱java", f));
 
            //close
            document.close();
 
            System.out.println("Done");
         
        } catch (FileNotFoundException | DocumentException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
 
    }
}

iText框架阅读PDF

package com.java265;
 
import com.itextpdf.text.pdf.PdfReader;
import com.itextpdf.text.pdf.parser.PdfTextExtractor;
 
import java.io.IOException;
 
public class PdfReadExample {
 
    private static final String FILE_NAME = "/tmp/itext.pdf";
 
    public static void main(String[] args) {
 
        PdfReader reader;
 
        try {
 
            reader = new PdfReader("f:/itext.pdf");
 
            // pageNumber = 1
            String textFromPage = PdfTextExtractor.getTextFromPage(reader, 1);
 
            System.out.println(textFromPage);
 
            reader.close();
 
        } catch (IOException e) {
            e.printStackTrace();
        }
 
    }
 
}