androidGLUESigner.pdf.PDFSigExtractor.java Source code

Introduction

Here is the source code for androidGLUESigner.pdf.PDFSigExtractor.java

Source

/**
 * 
 */
/*
* This program is free software; you can redistribute it and/or modify it under the terms of the 
* GNU Affero General Public License version 3 as published by the Free Software Foundation 
* with the addition of the following permission added to Section 15 as permitted in Section 7(a): 
* FOR ANY PART OF THE COVERED WORK IN WHICH THE COPYRIGHT IS OWNED BY Glue Software Engineering AG, 
* Glue Software Engineering AG DISCLAIMS THE WARRANTY OF NON INFRINGEMENT OF THIRD PARTY RIGHTS.
* 
* This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; 
* without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. 
* See the GNU Affero General Public License for more details. You should have received a copy 
* of the GNU Affero General Public License along with this program; if not, 
* see http://www.gnu.org/licenses or write to the Free Software Foundation, 
* Inc., 51 Franklin Street, Fifth Floor, Boston, MA, 02110-1301 USA.
    
* The interactive user interfaces in modified source and object code versions of this program 
* must display Appropriate Legal Notices, as required under Section 5 of the GNU Affero General Public License.
* 
* In accordance with Section 7(b) of the GNU Affero General Public License, 
* a covered work must retain the producer line in every PDF that is created or manipulated using GlueSigner.
* 
* For more information, please contact Glue Software Engineering AG at this address: info@glue.ch
*/

package androidGLUESigner.pdf;

import java.io.IOException;
import java.util.ArrayList;

import android.graphics.Rect;
import androidGLUESigner.models.SignatureInfo;
import androidGLUESigner.models.SignatureInfo.SignatureType;

import com.lowagie.text.Rectangle;
import com.lowagie.text.pdf.AcroFields;
import com.lowagie.text.pdf.PdfDictionary;
import com.lowagie.text.pdf.PdfName;
import com.lowagie.text.pdf.PdfReader;

/**
 * Extracts the signature field from a PDF file
 * @author roland
 *
 */
public class PDFSigExtractor {

    /**
     * extracts the signature field for previewing.
     * @throws IOException 
     */
    public static ArrayList<SignatureInfo> getSignatureInfo(String inputPath) {
        PdfReader reader;
        try {
            reader = new PdfReader(inputPath);
        } catch (IOException e) {
            return new ArrayList<SignatureInfo>();
        }
        AcroFields af = reader.getAcroFields();
        ArrayList names = af.getSignatureNames();
        ArrayList<SignatureInfo> signatures = new ArrayList<SignatureInfo>();
        // For every signature :
        for (int k = 0; k < names.size(); ++k) {
            String name = (String) names.get(k);
            SignatureInfo sigInfo = new SignatureInfo();
            // get coordinates
            float[] position = af.getFieldPositions(name);
            // page number
            float page = position[0];
            // left
            float llx = position[1];
            // bottom
            float lly = position[2];
            // right
            float urx = position[3];
            // top
            float ury = position[4];

            // get size of pdf page
            Rectangle size = reader.getPageSize((int) page);
            float height = size.getHeight();
            // subtract height to translate to Android canvas coordinate system
            lly = height - lly;
            ury = height - ury;
            float ulx = llx;

            // create a Rectangle from obtained signature field coordinates
            Rect sigRect = new Rect((int) ulx, (int) ury, (int) urx, (int) lly);
            sigInfo.setGraphicRect(sigRect, 1.0f);
            // obtain additional information like reason, location, ...
            PdfDictionary sig = af.getSignatureDictionary(name);
            sigInfo.setSignatureName(sig.getAsString(PdfName.NAME).toString());
            sigInfo.setSignatureLocation(sig.getAsString(PdfName.LOCATION).toString());
            sigInfo.setSignatureReason(sig.getAsString(PdfName.REASON).toString());
            sigInfo.setSignatureType(SignatureType.NORMAL);
            sigInfo.setPageNumber((int) page);
            // add new signature information to signatures
            signatures.add(sigInfo);
        }
        return signatures;
    }
}