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January 27, 2018 07:27
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| /* | |
| * Copyright 2018 Pamarin.com | |
| */ | |
| package com.pamarin.util; | |
| import com.lowagie.text.Document; | |
| import com.lowagie.text.DocumentException; | |
| import com.lowagie.text.PageSize; | |
| import com.lowagie.text.Rectangle; | |
| import com.lowagie.text.pdf.PdfContentByte; | |
| import com.lowagie.text.pdf.PdfImportedPage; | |
| import com.lowagie.text.pdf.PdfReader; | |
| import com.lowagie.text.pdf.PdfWriter; | |
| import java.io.File; | |
| import java.io.FileInputStream; | |
| import java.io.FileOutputStream; | |
| import java.io.IOException; | |
| import java.io.InputStream; | |
| import java.io.OutputStream; | |
| import java.io.UncheckedIOException; | |
| import org.slf4j.Logger; | |
| import org.slf4j.LoggerFactory; | |
| /** | |
| * @author jittagornp <http://jittagornp.me> create : 2018/01/26 | |
| */ | |
| public class PdfSizeUtils { | |
| private static final Logger LOG = LoggerFactory.getLogger(PdfSizeUtils.class); | |
| private static final float A4_WIDTH = PageSize.A4.getWidth(); | |
| private static final float A4_HEIGHT = PageSize.A4.getHeight(); | |
| private PdfSizeUtils() { | |
| } | |
| private static boolean isA4(float width, float height) { | |
| return (width == A4_WIDTH && height == A4_HEIGHT); | |
| } | |
| public static boolean isA4(File srcPdf) { | |
| PdfReader reader = null; | |
| try (InputStream intputStream = new FileInputStream(srcPdf)) { | |
| reader = new PdfReader(intputStream); | |
| Rectangle pageSize = reader.getPageSize(1);//first page | |
| boolean isA4 = isA4(pageSize.getWidth(), pageSize.getHeight()); | |
| LOG.debug("PDF \"{}\"", srcPdf.getAbsolutePath()); | |
| LOG.debug("Size {}x{} (A4 : {}x{}) is A4 => {}", | |
| pageSize.getWidth(), | |
| pageSize.getHeight(), | |
| A4_WIDTH, | |
| A4_HEIGHT, | |
| isA4 | |
| ); | |
| return isA4; | |
| } catch (IOException ex) { | |
| throw new UncheckedIOException(ex); | |
| } finally { | |
| if (reader != null) { | |
| reader.close(); | |
| } | |
| } | |
| } | |
| public static File convertToA4(File srcPdf, File destFile) { | |
| try (InputStream intputStream = new FileInputStream(srcPdf); | |
| OutputStream outputStream = new FileOutputStream(destFile)) { | |
| PdfReader reader = null; | |
| PdfWriter writer = null; | |
| Document document = null; | |
| try { | |
| reader = new PdfReader(intputStream); | |
| document = new Document(new Rectangle(A4_WIDTH, A4_HEIGHT)); | |
| writer = PdfWriter.getInstance(document, outputStream); | |
| document.open(); | |
| PdfContentByte content = writer.getDirectContent(); | |
| int numberOfPages = reader.getNumberOfPages(); | |
| for (int i = 1; i <= numberOfPages; i++) { | |
| PdfImportedPage page = writer.getImportedPage(reader, i); | |
| float scale = getA4Scale(page); | |
| content.addTemplate(page, scale, 0, 0, scale, 0, 0); | |
| document.newPage(); | |
| } | |
| } finally { | |
| if (document != null) { | |
| document.close(); | |
| } | |
| if (writer != null) { | |
| writer.close(); | |
| } | |
| if (reader != null) { | |
| reader.close(); | |
| } | |
| } | |
| return destFile; | |
| } catch (DocumentException | IOException ex) { | |
| throw new RuntimeException(ex); | |
| } | |
| } | |
| private static float getA4Scale(PdfImportedPage page) { | |
| float scaleX = A4_WIDTH / page.getWidth(); | |
| float scaleY = A4_HEIGHT / page.getHeight(); | |
| return Math.min(scaleX, scaleY); | |
| } | |
| } |
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