1 files changed, 131 insertions, 0 deletions
diff --git a/src/pdf2book/FileConverter.java b/src/pdf2book/FileConverter.java
new file mode 100644
index 0000000..a4ca54a
--- /dev/null
+++ b/src/pdf2book/FileConverter.java
@@ -0,0 +1,131 @@
+package pdf2book;
+
+import org.apache.pdfbox.pdmodel.PDDocument;
+import org.apache.pdfbox.pdmodel.PDPage;
+
+import java.io.File; 
+import java.io.IOException; 
+
+import java.util.ArrayList;
+
+public class FileConverter {
+	
+	private File inputFile;
+	private File outputFile;
+	
+	FileConverter(File inputFile, File outputFile) throws IOException {
+			this.inputFile = inputFile;
+			this.outputFile = outputFile;
+	}
+
+	boolean convert(boolean isQuarters) throws IOException {
+		
+		//Loading an existing PDF document
+		PDDocument original = PDDocument.load(inputFile); //Input file name goes here
+
+		//Rearrange pages to make the division
+		while (original.getNumberOfPages() % 4 != 0) {
+			original.addPage(new PDPage());
+		}
+		ArrayList<PDDocument> originalDivisions = new ArrayList<PDDocument>();
+		originalDivisions.add(new PDDocument());
+		int size = original.getNumberOfPages() / 4;
+		int divisionNumber = 0;
+
+		for (int i = 0; i < size; i++) {
+			originalDivisions.get(divisionNumber).addPage(original.getPage(4 * i));
+			originalDivisions.get(divisionNumber).addPage(original.getPage(4 * i + 1));
+			originalDivisions.get(divisionNumber).addPage(original.getPage(4 * i + 2));
+			originalDivisions.get(divisionNumber).addPage(original.getPage(4 * i + 3));
+			if ((i + 1) * Math.ceil(size / 8.0) / size >= divisionNumber + 1) {
+				if(i + 1 < size) {
+					originalDivisions.add(new PDDocument());
+				}
+				divisionNumber++;
+			}
+		}
+
+		//Add pages to correct count
+		ArrayList<PDDocument> arrangedDivisions = new ArrayList<PDDocument>();
+		for (PDDocument doc : originalDivisions) {
+			PDDocument temp = new PDDocument();
+			for (int i = 0; i < (32 - doc.getNumberOfPages()) / 2; i++) {
+				temp.addPage(new PDPage());
+			}
+			for (int i = 0; i < doc.getNumberOfPages(); i++) {
+				temp.addPage(doc.getPage(i));
+			}
+			for (int i = 0; i < (32 - doc.getNumberOfPages()) / 2; i++) {
+				temp.addPage(new PDPage());
+			}
+			arrangedDivisions.add(temp);
+		}
+
+		//Rearrange Pages
+		ArrayList<PDDocument> rearrangedDivisions = isQuarters ? 
+				rearrangeQuarters(arrangedDivisions) :
+				rearrangeSixteenths(arrangedDivisions);
+
+		//Combine Pages
+		PDDocument rearranged = new PDDocument();
+		for (PDDocument doc : rearrangedDivisions) {
+			for (int i = 0; i < doc.getNumberOfPages(); i++) {
+				rearranged.addPage(doc.getPage(i));
+			}
+		}
+
+		//Save PDF document and close
+		rearranged.save(outputFile); //Output file name goes here
+		
+		//Close all documents
+		for (PDDocument doc : rearrangedDivisions) {
+			doc.close();
+		}
+		for (PDDocument doc : arrangedDivisions) {
+			doc.close();
+		}
+		for (PDDocument doc : originalDivisions) {
+			doc.close();
+		}
+		rearranged.close();
+		original.close();
+		
+		return true;
+	} 
+	
+	ArrayList<PDDocument> rearrangeQuarters(ArrayList<PDDocument> arrangedDivisions) throws IOException {		
+		ArrayList<PDDocument> rearrangedDivisions = new ArrayList<PDDocument>();
+		  for (PDDocument doc : arrangedDivisions) {
+			  PDDocument temp = new PDDocument();
+	    	  for (int i = 0; i < 16; i+=4) {
+	    		  for (int j = 0; j < 4; j+=2) {
+	    			  temp.addPage(doc.getPage(i + j));
+	    			  temp.addPage(doc.getPage(31 - i - j));
+	    		  }
+	    		  for (int j = 1; j < 4; j+=2) {
+	    			  temp.addPage(doc.getPage(i + j));
+	    			  temp.addPage(doc.getPage(31 - i - j));
+	    		  }
+	      	  }
+	    	  rearrangedDivisions.add(temp);
+		}
+		return rearrangedDivisions;
+	}
+	
+	ArrayList<PDDocument> rearrangeSixteenths(ArrayList<PDDocument> arrangedDivisions) throws IOException {		
+		ArrayList<PDDocument> rearrangedDivisions = new ArrayList<PDDocument>();		
+		for (PDDocument doc : arrangedDivisions) {
+			PDDocument temp = new PDDocument();
+			for (int i = 0; i < 16; i+=2) {
+				temp.addPage(doc.getPage(i));
+				temp.addPage(doc.getPage(31 - i));
+			}
+			for (int i = 1; i < 16; i+=2) {
+				temp.addPage(doc.getPage(i));
+				temp.addPage(doc.getPage(31 - i));
+			}
+			rearrangedDivisions.add(temp);
+		}
+		return rearrangedDivisions;
+	}
+}