How to Read PDF File in Java

This article will explore how to create a PDF reader, to open a PDF file in your software application programmatically. To perform this task effectively, IronPDF for Java is one such system library which helps open and read PDF file using filename in Java program.

IronPDF

IronPDF - Java library is built on top of the already successful .NET Framework. This makes IronPDF a versatile tool for working with PDF documents compared to other class libraries such as Apache PDFBox. It provides the facility to extract/parse content, load text, and load images. It also provides options to customize the PDF pages such as page layout, margins, header and footer, page orientation and much more.

In addition to this, IronPDF also supports conversion from other file formats, protecting PDFs with a password, digital signing, merging, and splitting PDF documents.

How to Read PDF Files in Java

Prerequisites

To use IronPDF to make a Java PDF reader, it is necessary to ensure that the following components are installed on the computer:

1. JDK - Java Development Kit is required for building and running Java programs. If it is not installed, download it from the Oracle Website.
2. IDE - Integrated Development Environment is software that helps write, edit, and debug a program. Download any IDE for Java. E.g. Eclipse, NetBeans, IntelliJ.
3. Maven - Maven is an automation tool that helps download libraries from the Central Repository. Download it from the Apache Maven website.
4. IronPDF - Finally, IronPDF is required to read the PDF file in Java. This needs to be added as a dependency in your Java Maven Project. Include the IronPDF artifact along with the slf4j dependency in the pom.xml file as shown in the example below:

<dependency>
   <groupId>com.ironsoftware</groupId>
   <artifactId>com.ironsoftware</artifactId>
   <version>2024.9.1</version>
</dependency>

Adding Necessary Imports

Firstly, add the following code on top of the Java source file to reference all the required methods from IronPDF. Import org is optional in this example.

import com.ironsoftware.ironpdf.*;

import com.ironsoftware.ironpdf.*;

Next, configure IronPDF with a valid license key to use its method. Invoke the setLicenseKey method in the main method.

License.setLicenseKey("Your license key");

License.setLicenseKey("Your license key");

Note: You can get a free trial license key to create, read, and print PDFs.

Read Existing PDF File in Java

To read PDF files, there must be PDF files or one can be created. This article will use an already created PDF file. The code is simple and a two-step process to extract text from the document.

PdfDocument pdf = PdfDocument.fromFile(Paths.get("assets/sample.pdf"));
String text = pdf.extractAllText();
System.out.println(text);

PdfDocument pdf = PdfDocument.fromFile(Paths.get("assets/sample.pdf"));
String text = pdf.extractAllText();
System.out.println(text);

In the above code, fromFile opens a PDF document. The Paths.get method gets the directory of the file and is ready to extract content from the file. Then, [extractAllText](/java/object-reference/api/com/ironsoftware/ironpdf/PdfDocument.html#extractAllText()) reads all the text in the document.

The output is below:

Reading PDF Text Output

Read Text from a Specific Page

IronPDF can also read content from a specific page in a PDF. The extractTextFromPage method uses a PageSelection object to accept a range of page(s) from which text will be read.

In the following example, the text is extracted from the second page of the PDF document. PageSelection.singlePage takes the index of the page which needs to be extracted.

PdfDocument pdf = PdfDocument.fromFile(Paths.get("assets/sample.pdf"));
String text = pdf.extractTextFromPage(PageSelection.singlePage(1));
System.out.println(text);

PdfDocument pdf = PdfDocument.fromFile(Paths.get("assets/sample.pdf"));
String text = pdf.extractTextFromPage(PageSelection.singlePage(1));
System.out.println(text);

Reading PDF Text Output

Other methods available in the PageSelection class which can be used to extract text from various pages include: [firstPage](/java/object-reference/api/com/ironsoftware/ironpdf/edit/PageSelection.html#lastPage()), [lastPage](/java/object-reference/api/com/ironsoftware/ironpdf/edit/PageSelection.html#firstPage()), pageRange, and [allPages](/java/object-reference/api/com/ironsoftware/ironpdf/edit/PageSelection.html#allPages()).

Read Text from a Newly-Generated PDF File

Search text can also be performed from a newly generated PDF file from either an HTML file or URL. The following sample code generates PDF from URL and extracts all text from the website.

PdfDocument pdf = PdfDocument.renderUrlAsPdf("https://unsplash.com/");
String text = pdf.extractAllText();
System.out.println("Text extracted from the website: " + text);

PdfDocument pdf = PdfDocument.renderUrlAsPdf("https://unsplash.com/");
String text = pdf.extractAllText();
System.out.println("Text extracted from the website: " + text);

Read from a New File

IronPDF can also be used to extract images from PDF files.

The complete code is as follows:

import com.ironsoftware.ironpdf.License;
import com.ironsoftware.ironpdf.PdfDocument;
import com.ironsoftware.ironpdf.edit.PageSelection;

import java.io.IOException;
import java.nio.file.Paths;

public class Main {
    public static void main(String[] args) throws IOException {

        License.setLicenseKey("YOUR LICENSE KEY HERE");

        PdfDocument pdf = PdfDocument.fromFile(Paths.get("assets/sample.pdf"));
        String text = pdf.extractTextFromPage(PageSelection.singlePage(1));
        System.out.println(text);

        pdf = PdfDocument.renderUrlAsPdf("https://unsplash.com/");
        text = pdf.extractAllText();
        System.out.println("Text extracted from the website: " + text);

    }
}

import com.ironsoftware.ironpdf.License;
import com.ironsoftware.ironpdf.PdfDocument;
import com.ironsoftware.ironpdf.edit.PageSelection;

import java.io.IOException;
import java.nio.file.Paths;

public class Main {
    public static void main(String[] args) throws IOException {

        License.setLicenseKey("YOUR LICENSE KEY HERE");

        PdfDocument pdf = PdfDocument.fromFile(Paths.get("assets/sample.pdf"));
        String text = pdf.extractTextFromPage(PageSelection.singlePage(1));
        System.out.println(text);

        pdf = PdfDocument.renderUrlAsPdf("https://unsplash.com/");
        text = pdf.extractAllText();
        System.out.println("Text extracted from the website: " + text);

    }
}

Summary

This article explained how to open and read PDFs in Java using IronPDF.

IronPDF helps easily create PDFs from HTML or URL and also convert from different file formats. It also helps in getting PDF tasks done quickly and easily.

Try IronPDF for 30-days and find out how well it works for you in production. Commercial licenses start only from $749.