Example usage for java.nio.channels FileChannel map

List of usage examples for java.nio.channels FileChannel map

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Introduction

In this page you can find the example usage for java.nio.channels FileChannel map.

Prototype

public abstract MappedByteBuffer map(MapMode mode, long position, long size) throws IOException;

Source Link

Document

Maps a region of this channel's file directly into memory.

Usage

From source file:com.alibaba.otter.shared.common.utils.NioUtilsPerformance.java

public static void mappedTest(File source, File target) throws Exception {
    FileInputStream fis = null;/*from  ww w . j  av  a  2s .co m*/
    FileOutputStream fos = null;
    MappedByteBuffer mapbuffer = null;

    try {
        long fileSize = source.length();
        final byte[] outputData = new byte[(int) fileSize];
        fis = new FileInputStream(source);
        fos = new FileOutputStream(target);
        FileChannel sChannel = fis.getChannel();

        target.createNewFile();

        mapbuffer = sChannel.map(FileChannel.MapMode.READ_ONLY, 0, fileSize);
        for (int i = 0; i < fileSize; i++) {
            outputData[i] = mapbuffer.get();
        }

        mapbuffer.clear();
        fos.write(outputData);
        fos.flush();
    } finally {
        IOUtils.closeQuietly(fis);
        IOUtils.closeQuietly(fos);

        if (mapbuffer == null) {
            return;
        }

        final Object buffer = mapbuffer;

        AccessController.doPrivileged(new PrivilegedAction() {

            public Object run() {
                try {
                    Method clean = buffer.getClass().getMethod("cleaner", new Class[0]);

                    if (clean == null) {
                        return null;
                    }
                    clean.setAccessible(true);
                    sun.misc.Cleaner cleaner = (sun.misc.Cleaner) clean.invoke(buffer, new Object[0]);
                    cleaner.clean();
                } catch (Throwable ex) {
                }

                return null;
            }
        });
    }
}

From source file:edu.umich.flowfence.common.ParceledPayload.java

public static ParceledPayload fromParcel(Parcel p) {
    byte[] data = p.createByteArray();
    if (data == null) {
        // Null data = data's stored in an ashmem region.
        try (ParcelFileDescriptor pfd = p.readFileDescriptor()) {
            FileDescriptor fd = pfd.getFileDescriptor();
            int size = MemoryFile.getSize(fd);
            if (size == -1) {
                throw new ParcelFormatException("ParceledPayload blob is not ashmem");
            }/*  w w w.j  ava 2  s.  co  m*/
            data = new byte[size];
            FileInputStream fis = new FileInputStream(fd);
            FileChannel chan = fis.getChannel();
            MappedByteBuffer mapping = chan.map(FileChannel.MapMode.READ_ONLY, 0, size);
            mapping.get(data);
        } catch (IOException e) {
            Log.e(TAG, "Couldn't unparcel - not an ashmem region?", e);
            ParcelFormatException pfe = new ParcelFormatException("Exception reading blob for ParceledPayload");
            pfe.initCause(e);
            throw pfe;
        }
    }
    return new ParceledPayload(data);
}

From source file:nl.b3p.applet.local.Shapefiles.java

/** Returns a JSON object with shapefile and DBF metadata.
 * //from www.ja  v  a 2  s.  c  o  m
 * @param file the shapefile to read
 * @return a JSON object, read the code to find out which properties
 */
public static String getMetadata(String file) throws IOException, JSONException {

    if (!file.toLowerCase().endsWith(".shp")) {
        throw new IllegalArgumentException("File does not end with .shp: " + file);
    }

    FileChannel channel = new FileInputStream(file).getChannel();
    ShapefileHeader header = new ShapefileHeader();
    ByteBuffer bb = channel.map(FileChannel.MapMode.READ_ONLY, 0, channel.size());
    header.read(bb, true);
    channel.close();
    channel = null;
    file = file.substring(0, file.length() - 4) + ".dbf";

    JSONObject j = new JSONObject();
    j.put("type", header.getShapeType().name);
    j.put("version", header.getVersion());
    j.put("minX", header.minX());
    j.put("minY", header.minY());
    j.put("maxX", header.maxX());
    j.put("maxY", header.maxY());

    JSONObject dbf = new JSONObject();
    j.put("dbf", dbf);
    try {
        channel = new FileInputStream(file).getChannel();
        DbaseFileHeader dheader = new DbaseFileHeader();
        bb = channel.map(FileChannel.MapMode.READ_ONLY, 0, channel.size());
        dheader.readHeader(bb);
        dbf.put("numRecords", dheader.getNumRecords());
        JSONArray fields = new JSONArray();
        dbf.put("fields", fields);
        for (int i = 0; i < dheader.getNumFields(); i++) {
            JSONObject field = new JSONObject();
            fields.put(field);
            field.put("name", dheader.getFieldName(i));
            field.put("length", dheader.getFieldLength(i));
            field.put("decimalCount", dheader.getFieldDecimalCount(i));
            field.put("class", dheader.getFieldClass(i).getName().toString());
            field.put("type", dheader.getFieldType(i) + "");
        }
    } catch (Exception e) {
        dbf.put("error", e.toString());
    } finally {
        if (channel != null) {
            channel.close();
        }
    }

    file = file.substring(0, file.length() - 4) + ".prj";
    File f = new File(file);
    String prj = null;
    if (f.exists()) {
        Scanner s = new Scanner(f);
        prj = "";
        try {
            while (s.hasNextLine()) {
                if (prj.length() > 0) {
                    prj += "\n";
                }
                prj += s.nextLine();
            }
        } finally {
            s.close();
        }
    }
    j.put("prj", prj);

    return j.toString();
}

From source file:org.sleuthkit.autopsy.recentactivity.Util.java

public static String readFile(String path) throws IOException {
    FileInputStream stream = new FileInputStream(new File(path));
    try {/*from w w  w  .  ja va  2  s.c  om*/
        FileChannel fc = stream.getChannel();
        MappedByteBuffer bb = fc.map(FileChannel.MapMode.READ_ONLY, 0, fc.size());
        /*
         * Instead of using default, pass in a decoder.
         */
        return Charset.defaultCharset().decode(bb).toString();
    } finally {
        stream.close();
    }
}

From source file:com.project.utilities.Utilities.java

public static ArrayList<ViolationDataModel> readViolationJSONFileToArray() {
    ArrayList<ViolationDataModel> violation = new ArrayList<ViolationDataModel>();
    Gson gson = new Gson();
    String jsonStr = "";
    try {//from  ww  w  .  ja v a 2  s .  c  o  m
        File jsonFile = new File(Constants.EXTERNAL_DIRECTORY + "/" + Constants.FILENAME_VIOLATION_JSON);

        if (!jsonFile.exists()) {
            Log.e("VIOLATION_JSON_LIST", "Error reading file");
        } else {
            Log.e("readJsonFile", "File Found");
        }

        FileInputStream stream = new FileInputStream(jsonFile);
        try {
            FileChannel fc = stream.getChannel();
            MappedByteBuffer byteBuffer = fc.map(FileChannel.MapMode.READ_ONLY, 0, fc.size());
            jsonStr = Charset.defaultCharset().decode(byteBuffer).toString();
        } finally {
            stream.close();
        }
    } catch (Exception e) {
        Log.e("readJsonFile", e.getMessage());
    }

    try {
        JSONObject jsonContent = new JSONObject(jsonStr);
        violation = gson.fromJson(jsonContent.getString("data"),
                new TypeToken<ArrayList<ViolationDataModel>>() {
                }.getType());
    } catch (JSONException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
        Log.e("Error GSON", e.getMessage().toString());
    }
    return violation;
}

From source file:com.bazaarvoice.seo.sdk.util.BVUtility.java

public static String readFile(String path) throws IOException {
    FileInputStream stream = new FileInputStream(new File(path));
    try {//  w  w  w . j av a 2 s . c o  m
        FileChannel fc = stream.getChannel();
        MappedByteBuffer bb = fc.map(FileChannel.MapMode.READ_ONLY, 0, fc.size());
        return Charset.forName("UTF-8").decode(bb).toString();
    } finally {
        stream.close();
    }
}

From source file:nl.b3p.catalog.arcgis.Shapefiles.java

/** Returns a JSON object with shapefile and DBF metadata.
 *
 * @param file the shapefile to read//from  ww w .  j ava2 s .c om
 * @return a JSON object, read the code to find out which properties
 */
public static String getMetadata(String file) throws IOException, JSONException {

    if (!file.toLowerCase().endsWith(".shp")) {
        throw new IllegalArgumentException("File does not end with .shp: " + file);
    }

    JSONObject j = new JSONObject();

    String localFilename = new File(file).getName();
    String title = "";
    int dotIndex = localFilename.lastIndexOf(".");
    if (dotIndex > 0) {
        title = localFilename.substring(0, dotIndex);
    } else if (dotIndex == 0) {
        title = localFilename.substring(1);
    }
    j.put("title", title);

    FileChannel channel = new FileInputStream(file).getChannel();
    ShapefileHeader header = new ShapefileHeader();
    ByteBuffer bb = channel.map(FileChannel.MapMode.READ_ONLY, 0, channel.size());
    header.read(bb, true);
    channel.close();
    channel = null;
    file = file.substring(0, file.length() - 4) + ".dbf";

    j.put("type", header.getShapeType().name);
    j.put("version", header.getVersion());
    j.put("minX", header.minX());
    j.put("minY", header.minY());
    j.put("maxX", header.maxX());
    j.put("maxY", header.maxY());

    JSONObject dbf = new JSONObject();
    j.put("dbf", dbf);
    try {
        channel = new FileInputStream(file).getChannel();
        DbaseFileHeader dheader = new DbaseFileHeader();
        bb = channel.map(FileChannel.MapMode.READ_ONLY, 0, channel.size());
        dheader.readHeader(bb);
        dbf.put("numRecords", dheader.getNumRecords());
        JSONArray fields = new JSONArray();
        dbf.put("fields", fields);
        for (int i = 0; i < dheader.getNumFields(); i++) {
            JSONObject field = new JSONObject();
            fields.put(field);
            field.put("name", dheader.getFieldName(i));
            field.put("length", dheader.getFieldLength(i));
            field.put("decimalCount", dheader.getFieldDecimalCount(i));
            field.put("class", dheader.getFieldClass(i).getName().toString());
            field.put("type", dheader.getFieldType(i) + "");
        }
    } catch (Exception e) {
        dbf.put("error", e.toString());
    } finally {
        if (channel != null) {
            channel.close();
        }
    }

    file = file.substring(0, file.length() - 4) + ".prj";
    File f = new File(file);
    String prj = null;
    if (f.exists()) {
        Scanner s = new Scanner(f);
        prj = "";
        try {
            while (s.hasNextLine()) {
                if (prj.length() > 0) {
                    prj += "\n";
                }
                prj += s.nextLine();
            }
        } finally {
            s.close();
        }
    }
    j.put("prj", prj);

    return j.toString();
}

From source file:Grep.java

public static void setFile(File f) throws IOException {
    FileInputStream fis = new FileInputStream(f);
    FileChannel fc = fis.getChannel();

    // Get the file's size and then map it into memory
    int sz = (int) fc.size();
    MappedByteBuffer bb = fc.map(FileChannel.MapMode.READ_ONLY, 0, sz);
    // Decode the file into a char buffer
    indexFile = decoder.decode(bb);//from   w ww  . j ava 2 s  .c  om

    fc.close();
}

From source file:org.uva.itast.blended.omr.pages.PDFPageImage.java

/**
 * @param filePath2/* ww  w  .  j a v a 2s.  c  om*/
 * @throws IOException 
 */
public static PDFFile loadPDFFile(File inputpath) throws IOException {
    RandomAccessFile raf = new RandomAccessFile(inputpath, "r"); //se carga la imagen pdf para leerla
    FileChannel channel = raf.getChannel();
    ByteBuffer buf = channel.map(FileChannel.MapMode.READ_ONLY, 0, channel.size());
    PDFFile pdffile = new PDFFile(buf);
    return pdffile;
}

From source file:yui.classes.utils.IOUtils.java

public static void fastCopy(File source, File dest) throws IOException {
    FileInputStream fi = new FileInputStream(source);
    FileChannel fic = fi.getChannel();
    MappedByteBuffer mbuf = fic.map(FileChannel.MapMode.READ_ONLY, 0, source.length());
    fic.close();/*from  w  w w  .  j  a  v  a  2 s  .c  om*/
    fi.close();

    FileOutputStream fo = new FileOutputStream(dest);
    FileChannel foc = fo.getChannel();
    foc.write(mbuf);
    foc.close();
    fo.close();

}