> For the complete documentation index, see [llms.txt](https://docs.apryse.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.apryse.com/android/get-started/samples/pdfdocmemorytest.md).

# PDFDocMemory

Sample Java code for using Apryse SDK to read/write a PDF document from/to memory buffer. This is useful for applications that work with dynamic PDFdocuments that don't need to be saved/read from a di

Sample Java code for using Apryse SDK to read/write a PDF document from/to memory buffer. This is useful for applications that work with dynamic PDFdocuments that don't need to be saved/read from a disk. Learn more about our [Android SDK](/core/get-started/languages/java.md).

{% tabs %}
{% tab title="Java" %}
{% code lineNumbers="true" %}

```java
//---------------------------------------------------------------------------------------
// Copyright (c) 2001-2019 by PDFTron Systems Inc. All Rights Reserved.
// Consult legal.txt regarding legal and license information.
//---------------------------------------------------------------------------------------

package com.pdftron.android.pdfnetsdksamples.samples;

import com.pdftron.android.pdfnetsdksamples.OutputListener;
import com.pdftron.android.pdfnetsdksamples.PDFNetSample;
import com.pdftron.android.pdfnetsdksamples.R;
import com.pdftron.android.pdfnetsdksamples.util.Utils;
import com.pdftron.common.PDFNetException;
import com.pdftron.filters.FilterReader;
import com.pdftron.filters.MappedFile;
import com.pdftron.pdf.Element;
import com.pdftron.pdf.ElementReader;
import com.pdftron.pdf.ElementWriter;
import com.pdftron.pdf.PDFDoc;
import com.pdftron.pdf.Page;
import com.pdftron.pdf.PageIterator;
import com.pdftron.sdf.SDFDoc;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.ArrayList;

public class PDFDocMemoryTest extends PDFNetSample {

	private static OutputListener mOutputListener;

	private static ArrayList<String> mFileList = new ArrayList<>();

    public PDFDocMemoryTest() {
        setTitle(R.string.sample_pdfdocmemory_title);
        setDescription(R.string.sample_pdfdocmemory_description);
    }

	@Override
	public void run(OutputListener outputListener) {
		super.run(outputListener);
		mOutputListener = outputListener;
		mFileList.clear();
		printHeader(outputListener);


        // The following sample illustrates how to read/write a PDF document from/to
        // a memory buffer.  This is useful for applications that work with dynamic PDF
        // documents that don't need to be saved/read from a disk.
        try {
            // Read a PDF document in a memory buffer.
            MappedFile file = new MappedFile((Utils.getAssetTempFile(INPUT_PATH + "tiger.pdf").getAbsolutePath()));
            long file_sz = file.fileSize();

            FilterReader file_reader = new FilterReader(file);

            byte[] mem = new byte[(int) file_sz];

            long bytes_read = file_reader.read(mem);
            try (PDFDoc doc = new PDFDoc(mem)) {

                doc.initSecurityHandler();
                int num_pages = doc.getPageCount();

                ElementWriter writer = new ElementWriter();
                ElementReader reader = new ElementReader();
                Element element;

                // Create a duplicate of every page but copy only path objects

                for (int i = 1; i <= num_pages; ++i) {
                    PageIterator itr = doc.getPageIterator(2 * i - 1);
                    Page current = itr.next();
                    reader.begin(current);
                    Page new_page = doc.pageCreate(current.getMediaBox());
                    doc.pageInsert(itr, new_page);

                    writer.begin(new_page);
                    while ((element = reader.next()) != null)    // Read page contents
                    {
                        //if (element.getType() == Element.e_path)
                        writer.writeElement(element);
                    }

                    writer.end();
                    reader.end();
                }

                doc.save(Utils.createExternalFile("doc_memory_edit.pdf", mFileList).getAbsolutePath(), SDFDoc.SaveMode.REMOVE_UNUSED, null);

                // Save the document to a memory buffer.

                byte[] buf = doc.save(SDFDoc.SaveMode.REMOVE_UNUSED, null);
                // doc.Save(buf, buf_sz, Doc::e_linearized, NULL);

                // Write the contents of the buffer to the disk
                {
                    File outfile = new File(Utils.createExternalFile("doc_memory_edit.txt", mFileList).getAbsolutePath());
                    // output "doc_memory_edit.txt"
                    FileOutputStream fop = new FileOutputStream(outfile);
                    if (!outfile.exists()) {
                        outfile.createNewFile();
                    }
                    fop.write(buf);
                    fop.flush();
                    fop.close();
                }

                // Read some data from the file stored in memory
                reader.begin(doc.getPage(1));
                while ((element = reader.next()) != null) {
                    if (element.getType() == Element.e_path) mOutputListener.print("Path, ");
                }
                reader.end();
                
                mOutputListener.println("\n\nDone. Result saved in doc_memory_edit.pdf and doc_memory_edit.txt ...");
            }
        }
        catch (PDFNetException e)
        {
            mOutputListener.printError(e.getStackTrace());
            mOutputListener.printError(e.getStackTrace());
        }
        catch (Exception e)
        {
            mOutputListener.printError(e.getStackTrace());
        }

		for (String file : mFileList) {
			addToFileList(file);
		}
		printFooter(outputListener);
	}

}
```

{% endcode %}
{% endtab %}

{% tab title="Kotlin" %}
{% code lineNumbers="true" %}

```kotlin
//---------------------------------------------------------------------------------------
// Copyright (c) 2001-2019 by PDFTron Systems Inc. All Rights Reserved.
// Consult legal.txt regarding legal and license information.
//---------------------------------------------------------------------------------------
package com.pdftron.android.pdfnetsdksamples.samples

import com.pdftron.android.pdfnetsdksamples.OutputListener
import com.pdftron.android.pdfnetsdksamples.PDFNetSample
import com.pdftron.android.pdfnetsdksamples.R
import com.pdftron.android.pdfnetsdksamples.util.Utils
import com.pdftron.common.PDFNetException
import com.pdftron.filters.MappedFile
import com.pdftron.pdf.ElementWriter
import com.pdftron.pdf.PDFDoc
import com.pdftron.pdf.PageIterator
import com.pdftron.sdf.SDFDoc

class PDFDocMemoryTest : PDFNetSample() {
    override fun run(outputListener: OutputListener?) {
        super.run(outputListener)
        mOutputListener = outputListener
        mFileList.clear()
        printHeader(outputListener!!)

        // The following sample illustrates how to read/write a PDF document from/to
        // a memory buffer.  This is useful for applications that work with dynamic PDF
        // documents that don't need to be saved/read from a disk.
        try {
            // Read a PDF document in a memory buffer.
            val file = MappedFile(Utils.getAssetTempFile(INPUT_PATH.toString() + "tiger.pdf")!!.getAbsolutePath())
            val file_sz: Long = file.fileSize()
            val file_reader: com.pdftron.filters.FilterReader = com.pdftron.filters.FilterReader(file)
            val mem = ByteArray(file_sz.toInt())
            val bytes_read: Long = file_reader.read(mem)
            PDFDoc(mem).use { doc ->
                doc.initSecurityHandler()
                val num_pages: Int = doc.getPageCount()
                val writer = ElementWriter()
                val reader: com.pdftron.pdf.ElementReader = com.pdftron.pdf.ElementReader()
                var element: com.pdftron.pdf.Element?

                // Create a duplicate of every page but copy only path objects
                for (i in 1..num_pages) {
                    val itr: PageIterator = doc.getPageIterator(2 * i - 1)
                    val current: com.pdftron.pdf.Page? = itr.next()
                    reader.begin(current)
                    val new_page: com.pdftron.pdf.Page = doc.pageCreate(current!!.getMediaBox())
                    doc.pageInsert(itr, new_page)
                    writer.begin(new_page)
                    // Read page contents
                    while (true) {
                        element = reader.next()
                        if (element == null) {
                            break
                        }
                        //if (element.getType() == Element.e_path)
                        writer.writeElement(element)
                    }
                    writer.end()
                    reader.end()
                }
                doc.save(Utils.createExternalFile("doc_memory_edit.pdf", mFileList).getAbsolutePath(), SDFDoc.SaveMode.REMOVE_UNUSED, null)

                // Save the document to a memory buffer.
                val buf: ByteArray = doc.save(SDFDoc.SaveMode.REMOVE_UNUSED, null)
                // doc.Save(buf, buf_sz, Doc::e_linearized, NULL);

                // Write the contents of the buffer to the disk
                run({
                    val outfile: java.io.File = java.io.File(Utils.createExternalFile("doc_memory_edit.txt", mFileList).getAbsolutePath())
                    val fop: java.io.FileOutputStream = java.io.FileOutputStream(outfile)
                    if (!outfile.exists()) {
                        outfile.createNewFile()
                    }
                    fop.write(buf)
                    fop.flush()
                    fop.close()
                })

                // Read some data from the file stored in memory
                reader.begin(doc.getPage(1))
                while (true) {
                    element = reader.next()
                    if (element == null) {
                        break
                    }
                    if (element.getType() == com.pdftron.pdf.Element.e_path) mOutputListener!!.print("Path, ")
                }
                reader.end()
                mOutputListener!!.println("\n\nDone. Result saved in doc_memory_edit.pdf and doc_memory_edit.txt ...")
            }
        } catch (e: PDFNetException) {
            mOutputListener!!.printError(e.getStackTrace())
            mOutputListener!!.printError(e.getStackTrace())
        } catch (e: java.lang.Exception) {
            mOutputListener!!.printError(e.getStackTrace())
        }
        for (file in mFileList) {
            addToFileList(file)
        }
        printFooter(outputListener)
    }

    companion object {
        private var mOutputListener: OutputListener? = null
        private val mFileList: java.util.ArrayList<String> = java.util.ArrayList<String>()
    }

    init {
        setTitle(R.string.sample_pdfdocmemory_title)
        setDescription(R.string.sample_pdfdocmemory_description)
    }
}
```

{% endcode %}
{% endtab %}
{% endtabs %}


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