Set Zoom Factor and Viewer Preference for PDF Documents in Java

Zoom Factor lets you zoom the display by a scale factor, and the Viewer Preference allows you to control the way the document shall be presented. This article will introduce how to set Zoom Factor and Viewer Preference for PDF documents using Java codes.

TOOL: Free Spire.PDF for Java (you can get it from the link, or directly add it to your project by using the following Maven configurations)

<repositories>
<repository>
<id>com.e-iceblue</id>
<name>e-iceblue</name>
<url>https://repo.e-iceblue.com/nexus/content/groups/public/</url>
</repository>
</repositories>
<dependencies>
<dependency>
<groupId>e-iceblue</groupId>
<artifactId>spire.pdf.free</artifactId>
<version>4.4.1</version>
</dependency>
</dependencies>

USING THE CODE
Set Zoom Factor
You can find the following steps to set zoom factor for a PDF document using Java codes.
l  Load a PDF sample document using PdfDocument.loadFromFile() method
l  Get the specified page of PDF using PdfDocument.getPages().get() method
l  Set PDF destination mode and action
l  Set zoom factor using PdfDocument.setZoom() method
l  Save the resulting document to a specified path using PdfDocument.saveToFile() method
Full code sample are shown as below.
import com.spire.pdf.*;
import com.spire.pdf.actions.*;
import com.spire.pdf.general.*;
import java.awt.geom.*;

public class ZoomFactor {
    public static void main(String[] args) {
        //Load the sample document
        PdfDocument doc = new PdfDocument();
        doc.loadFromFile("C:\\Users\\Test1\\Desktop\\sample.pdf");

        //Get the first page of PDF
        PdfPageBase page = doc.getPages().get(0);

        //Set pdf destination
        PdfDestination dest = new PdfDestination(page);
        dest.setMode(PdfDestinationMode.Location);
        dest.setLocation(new Point2D.Float(-40f, -40f));

        //Set zoom factor
        dest.setZoom(0.8f);

        //Set action
        PdfGoToAction gotoAction = new PdfGoToAction(dest);
        doc.setAfterOpenAction(gotoAction);

        //Save pdf document
        String output = "output/setZoomFactor.pdf";
        doc.saveToFile(output);
    }
}
Output



Set Viewer Preference 
Free Spire.PDF for Java supports setting viewer preference for a PDF document, for example, you can 
specify whether to position the document’s window in the center of the screen using PdfDocument
.getViewerPreferences().setCenterWindow() method and whether the title of the document should be 
displayed in the window’s title bar using PdfDocument.getViewerPreferences().setDisplayTitle()
method. The code snippets below will give you detailed information.
import com.spire.pdf.*;

public class ViewerPreference {
    public static void main(String[] args) {
        //Load the sample document
        PdfDocument doc = new PdfDocument();
        doc.loadFromFile("C:\\Users\\Test1\\Desktop\\sample.pdf");

        //Set viewer reference
        doc.getViewerPreferences().setCenterWindow(true);
        doc.getViewerPreferences().setDisplayTitle(false);
        doc.getViewerPreferences().setFitWindow(false);
        doc.getViewerPreferences().setHideMenubar(true);
        doc.getViewerPreferences().setHideToolbar(true);
        doc.getViewerPreferences().setPageLayout(PdfPageLayout.Two_Column_Left);

        //Save pdf document
        String output = "output/viewerPreference.pdf";
        doc.saveToFile(output);
    }
}
Output