Java Code Examples for java.nio.MappedByteBuffer#hasRemaining()
The following examples show how to use
java.nio.MappedByteBuffer#hasRemaining() .
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Example 1
| Source File: YoloVisionTest.java From SoftwarePilot with MIT License | 6 votes |
|
byte[] read4k(){
try {
File file = new File(Environment.getExternalStorageDirectory().getPath()+"/AUAVtmp/fullPic.JPG");
//File file = new File("../tmp/pictmp.jpg");
FileChannel fileChannel = new RandomAccessFile(file, "r").getChannel();
MappedByteBuffer buffer = fileChannel.map(FileChannel.MapMode.READ_ONLY, 0, fileChannel.size());
pic = new byte[buffer.capacity()];
while(buffer.hasRemaining()){
int remaining = pic.length;
if(buffer.remaining() < remaining){
remaining = buffer.remaining();
}
buffer.get(pic, 0, remaining);
}
return pic;
} catch(Exception e){
e.printStackTrace();
}
return new byte[0];
}
Example 2
| Source File: Bug1169.java From spotbugs with GNU Lesser General Public License v2.1 | 6 votes |
|
@NoWarning("RCN,NP")
@Nonnull
public <R> R execute2(@Nonnull final Engine<R> engine, @Nonnull final Path path, @Nonnull final byte[] buffer)
throws UnsupportedOperationException, IOException {
try (FileChannel c = open(path, StandardOpenOption.READ)) {
engine.reset();
final long size = c.size();
long i = 0;
while (i < size) {
final MappedByteBuffer mb = c.map(MapMode.READ_ONLY, i, Math.min(size - i, Integer.MAX_VALUE));
final int bl = buffer.length;
while (mb.hasRemaining()) {
final int get = Math.min(mb.remaining(), bl);
mb.get(buffer, 0, get);
engine.update(buffer, 0, get);
i += get;
}
}
return engine.digest();
}
}
Example 3
| Source File: Bug1169.java From spotbugs with GNU Lesser General Public License v2.1 | 6 votes |
|
@NoWarning("RCN,NP")
@Nonnull
protected <R> R executeEngine(@Nonnull final Engine<R> engine, @Nonnull final Path path) throws IOException {
try (final FileChannel c = open(path, StandardOpenOption.READ)) {
engine.reset();
final MappedByteBuffer mb = c.map(MapMode.READ_ONLY, 0L, c.size());
final int bufferLength = 8*1024;
final byte[] buffer = new byte[bufferLength];
while (mb.hasRemaining()) {
final int get = Math.min(mb.remaining(), bufferLength);
mb.get(buffer, 0, get);
engine.update(buffer, 0, get);
}
return engine.digest();
}
}
Example 4
| Source File: VisionTest.java From SoftwarePilot with MIT License | 6 votes |
|
byte[] readImg(){
try {
//BufferedImage origImage = ImageIO.read(imgPath);
//ByteArrayOutputStream baos = new ByteArrayOutputStream();
//ImageIO.write(origImage, "jpg", baos);
//return baos.toByteArray();
File file = new File(Environment.getExternalStorageDirectory().getPath()+"/AUAVtmp/fullPic.JPG");
//File file = new File("../tmp/pictmp.jpg");
FileChannel fileChannel = new RandomAccessFile(file, "r").getChannel();
MappedByteBuffer buffer = fileChannel.map(FileChannel.MapMode.READ_ONLY, 0, fileChannel.size());
byte[] pic = new byte[buffer.capacity()];
while(buffer.hasRemaining()){
int remaining = pic.length;
if(buffer.remaining() < remaining){
remaining = buffer.remaining();
}
buffer.get(pic, 0, remaining);
}
return pic;
} catch(Exception e){
e.printStackTrace();
}
return new byte[0];
}
Example 5
| Source File: FileChannelUnitTest.java From tutorials with MIT License | 6 votes |
|
@Test
public void givenFile_whenReadAFileSectionIntoMemoryWithFileChannel_thenCorrect() throws IOException {
try (RandomAccessFile reader = new RandomAccessFile("src/test/resources/test_read.in", "r");
FileChannel channel = reader.getChannel();
ByteArrayOutputStream out = new ByteArrayOutputStream()) {
MappedByteBuffer buff = channel.map(FileChannel.MapMode.READ_ONLY, 6, 5);
if (buff.hasRemaining()) {
byte[] data = new byte[buff.remaining()];
buff.get(data);
assertEquals("world", new String(data, StandardCharsets.UTF_8));
}
}
}
Example 6
| Source File: BasicVision.java From SoftwarePilot with MIT License | 6 votes |
|
byte[] read4k(){
try {
File file = new File(Environment.getExternalStorageDirectory().getPath()+"/AUAVtmp/fullPic.JPG");
//File file = new File("../tmp/pictmp.jpg");
FileChannel fileChannel = new RandomAccessFile(file, "r").getChannel();
MappedByteBuffer buffer = fileChannel.map(FileChannel.MapMode.READ_ONLY, 0, fileChannel.size());
pic = new byte[buffer.capacity()];
while(buffer.hasRemaining()){
int remaining = pic.length;
if(buffer.remaining() < remaining){
remaining = buffer.remaining();
}
buffer.get(pic, 0, remaining);
}
return pic;
} catch(Exception e){
e.printStackTrace();
}
return new byte[0];
}
Example 7
| Source File: RoutineTemplate.java From SoftwarePilot with MIT License | 6 votes |
|
byte[] read4k(){
try {
File file = new File(Environment.getExternalStorageDirectory().getPath()+"/AUAVtmp/fullPic.JPG");
//File file = new File("../tmp/pictmp.jpg");
FileChannel fileChannel = new RandomAccessFile(file, "r").getChannel();
MappedByteBuffer buffer = fileChannel.map(FileChannel.MapMode.READ_ONLY, 0, fileChannel.size());
pic = new byte[buffer.capacity()];
while(buffer.hasRemaining()){
int remaining = pic.length;
if(buffer.remaining() < remaining){
remaining = buffer.remaining();
}
buffer.get(pic, 0, remaining);
}
return pic;
} catch(Exception e){
e.printStackTrace();
}
return new byte[0];
}
Example 8
| Source File: WaypointMissionTestBackup.java From SoftwarePilot with MIT License | 6 votes |
|
byte[] read4k(){
try {
File file = new File(Environment.getExternalStorageDirectory().getPath()+"/AUAVtmp/fullPic.JPG");
//File file = new File("../tmp/pictmp.jpg");
FileChannel fileChannel = new RandomAccessFile(file, "r").getChannel();
MappedByteBuffer buffer = fileChannel.map(FileChannel.MapMode.READ_ONLY, 0, fileChannel.size());
pic = new byte[buffer.capacity()];
while(buffer.hasRemaining()){
int remaining = pic.length;
if(buffer.remaining() < remaining){
remaining = buffer.remaining();
}
buffer.get(pic, 0, remaining);
}
return pic;
} catch(Exception e){
e.printStackTrace();
}
return new byte[0];
}
Example 9
| Source File: WaypointMissionTest.java From SoftwarePilot with MIT License | 6 votes |
|
byte[] read4k(){
try {
File file = new File(Environment.getExternalStorageDirectory().getPath()+"/AUAVtmp/fullPic.JPG");
//File file = new File("../tmp/pictmp.jpg");
FileChannel fileChannel = new RandomAccessFile(file, "r").getChannel();
MappedByteBuffer buffer = fileChannel.map(FileChannel.MapMode.READ_ONLY, 0, fileChannel.size());
pic = new byte[buffer.capacity()];
while(buffer.hasRemaining()){
int remaining = pic.length;
if(buffer.remaining() < remaining){
remaining = buffer.remaining();
}
buffer.get(pic, 0, remaining);
}
return pic;
} catch(Exception e){
e.printStackTrace();
}
return new byte[0];
}
Example 10
| Source File: WaypointMissionTest.java From SoftwarePilot with MIT License | 6 votes |
|
byte[] readWaypoint(String fname){
//read in the file
try{
File f = new File(Environment.getExternalStorageDirectory().getPath()+fname);
FileChannel fileChannel = new RandomAccessFile(f,"r").getChannel();
MappedByteBuffer buffer = fileChannel.map(FileChannel.MapMode.READ_ONLY,0,fileChannel.size());
data = new byte[buffer.capacity()];
while(buffer.hasRemaining()){
int remaining = data.length;
if (buffer.remaining()<remaining){
remaining = buffer.remaining();
}
buffer.get(data,0,remaining);
}
return data;
}catch (IOException e) {
e.printStackTrace();
}
return new byte[0];
}
Example 11
| Source File: AutoSelfie.java From SoftwarePilot with MIT License | 6 votes |
|
byte[] readImg(){
try {
//BufferedImage origImage = ImageIO.read(imgPath);
//ByteArrayOutputStream baos = new ByteArrayOutputStream();
//ImageIO.write(origImage, "jpg", baos);
//return baos.toByteArray();
File file = new File(Environment.getExternalStorageDirectory().getPath()+"/AUAVtmp/fullPic.JPG");
//File file = new File("../tmp/pictmp.jpg");
FileChannel fileChannel = new RandomAccessFile(file, "r").getChannel();
MappedByteBuffer buffer = fileChannel.map(FileChannel.MapMode.READ_ONLY, 0, fileChannel.size());
pic = new byte[buffer.capacity()];
while(buffer.hasRemaining()){
int remaining = pic.length;
if(buffer.remaining() < remaining){
remaining = buffer.remaining();
}
buffer.get(pic, 0, remaining);
}
return pic;
} catch(Exception e){
e.printStackTrace();
}
return new byte[0];
}
Example 12
| Source File: BasicRoutine.java From SoftwarePilot with MIT License | 6 votes |
|
byte[] read4k(){
try {
File file = new File(Environment.getExternalStorageDirectory().getPath()+"/AUAVtmp/fullPic.JPG");
//File file = new File("../tmp/pictmp.jpg");
FileChannel fileChannel = new RandomAccessFile(file, "r").getChannel();
MappedByteBuffer buffer = fileChannel.map(FileChannel.MapMode.READ_ONLY, 0, fileChannel.size());
pic = new byte[buffer.capacity()];
while(buffer.hasRemaining()){
int remaining = pic.length;
if(buffer.remaining() < remaining){
remaining = buffer.remaining();
}
buffer.get(pic, 0, remaining);
}
return pic;
} catch(Exception e){
e.printStackTrace();
}
return new byte[0];
}
Example 13
| Source File: GenericCopyUtil.java From PowerFileExplorer with GNU General Public License v3.0 | 5 votes |
|
private boolean copyFile(final FileChannel inChannel, final BufferedOutputStream bufferedOutputStream)
throws IOException {
final MappedByteBuffer inBuffer = inChannel.map(FileChannel.MapMode.READ_ONLY, 0, mSourceFile.size);
int count = -1;
final byte[] buffer = new byte[DEFAULT_BUFFER_SIZE];
while (inBuffer.hasRemaining() && count != 0) {
if (progressHandler.isCancelled) {
bufferedOutputStream.close();
return false;
}
final int tempPosition = inBuffer.position();
try {
// try normal way of getting bytes
final ByteBuffer tempByteBuffer = inBuffer.get(buffer);
count = tempByteBuffer.position() - tempPosition;
} catch (BufferUnderflowException exception) {
exception.printStackTrace();
// not enough bytes left in the channel to read, iterate over each byte and store
// in the buffer
// reset the counter bytes
count = 0;
final int length = buffer.length;
for (int i=0; i < length && inBuffer.hasRemaining(); i++) {
buffer[i] = inBuffer.get();
count++;
}
}
if (count != -1) {
bufferedOutputStream.write(buffer, 0, count);
ServiceWatcherUtil.POSITION = inBuffer.position();
}
}
bufferedOutputStream.flush();
return true;
}
Example 14
| Source File: MappedPageSourceIT.java From offheap-store with Apache License 2.0 | 5 votes |
|
@Test
public void testCreateLotsOfMappedBuffers() throws IOException {
final int size = 1024 * 1024;
final int count = 16;
MappedPageSource source = new MappedPageSource(dataFile);
try {
byte[] data = new byte[1024];
Arrays.fill(data, (byte) 0xff);
List<MappedPage> pages = new ArrayList<>();
for (int i = 0; i < count; i++) {
pages.add(source.allocate(size, false, false, null));
}
for (MappedPage p : pages) {
MappedByteBuffer b = p.asByteBuffer();
while (b.hasRemaining()) {
b.put(data);
}
b.force();
}
} finally {
source.close();
}
try (RandomAccessFile raf = new RandomAccessFile(source.getFile(), "r")) {
Assert.assertEquals(size * count, raf.length());
}
}
Example 15
| Source File: FileUtil.java From cc-dbp with Apache License 2.0 | 5 votes |
|
/**
* get an input stream for the file that is fast, trading memory for speed
*
* @param file
* @return InputStream
*/
public static InputStream fastStream(File file) {
FileInputStream fis = null;
FileChannel ch = null;
byte[] byteArray = null;
try {
fis = new FileInputStream(file);
if (fis != null) {
ch = fis.getChannel();
if (ch.size() > 1000000000) {
return new BufferedInputStream(fis, BUFFER_SIZE);
}
MappedByteBuffer mb = ch.map(FileChannel.MapMode.READ_ONLY, 0L, ch.size());
byteArray = new byte[mb.capacity()];
int got;
while (mb.hasRemaining()) {
got = Math.min(mb.remaining(), byteArray.length);
mb.get(byteArray, 0, got);
}
}
} catch (FileNotFoundException fnfe) {
throw new IOError(fnfe);
} catch (IOException ioe) {
throw new IOError(ioe);
} finally {
if (ch != null) {
try {
ch.close();
fis.close();
} catch (IOException ioe2) {
}
}
}
return new ByteArrayInputStream(byteArray);
}
Example 16
| Source File: FileChannelDemo03.java From javacore with Creative Commons Attribution Share Alike 4.0 International | 5 votes |
|
public static void main(String[] args) throws Exception {
File file = new File("d:" + File.separator + "out.txt");
FileInputStream input = new FileInputStream(file);
FileChannel fin = input.getChannel(); // 得到输入的通道
MappedByteBuffer mbb = fin.map(FileChannel.MapMode.READ_ONLY, 0, file.length());
byte[] data = new byte[(int) file.length()]; // 开辟空间接收内容
int foot = 0;
while (mbb.hasRemaining()) {
data[foot++] = mbb.get(); // 读取数据
}
System.out.println(new String(data)); // 输出内容
fin.close();
input.close();
}
Example 17
| Source File: CharReadingBenchmark.java From SimpleFlatMapper with MIT License | 5 votes |
|
@Benchmark
public void memoryMappedFile(Blackhole blackhole) throws IOException {
char[] buffer = new char[bufferSize];
try (FileChannel channel = FileChannel.open(file.toPath())) {
MappedByteBuffer byteBuffer = channel.map(FileChannel.MapMode.READ_ONLY, 0, channel.size());
CharsetDecoder charsetDecoder = charset.newDecoder();
while(byteBuffer.hasRemaining()) {
CoderResult coderResult = charsetDecoder.decode(byteBuffer, CharBuffer.wrap(buffer), true);
blackhole.consume(buffer);
}
}
}
Example 18
| Source File: FileUtil.java From Inspeckage with Apache License 2.0 | 5 votes |
|
public static Map<String, String> readMultiFile(SharedPreferences prefs, String folderName) {
Map<String, String> files = new HashMap<>();
try {
String absolutePath;
if (prefs.getBoolean(Config.SP_HAS_W_PERMISSION, false)) {
absolutePath = Environment.getExternalStorageDirectory().getAbsolutePath()+Config.P_ROOT+"/"+prefs.getString(Config.SP_PACKAGE,"")+"/"+ folderName;
} else {
absolutePath = prefs.getString(Config.SP_DATA_DIR, null)+Config.P_ROOT+"/"+folderName;
}
File folder = new File(absolutePath);
if (folder.listFiles() != null && folder.length() > 0) {
for (final File fileEntry : folder.listFiles()) {
if (fileEntry.exists() && fileEntry.isFile()) {
FileInputStream f = new FileInputStream(fileEntry.getAbsolutePath());
FileChannel ch = f.getChannel();
MappedByteBuffer mbb = ch.map(FileChannel.MapMode.READ_ONLY, 0L, ch.size());
String text = "";
while (mbb.hasRemaining()) {
String charsetName = "UTF-8";
CharBuffer cb = Charset.forName(charsetName).decode(mbb);
text = cb.toString();
}
files.put(fileEntry.getName(), text);
}
}
}
} catch (Exception e) {
e.printStackTrace();
}
return files;
}
Example 19
| Source File: TextFiles.java From Java-Coding-Problems with MIT License | 4 votes |
|
public static long countOccurrencesV5(Path path, String text) throws IOException {
if (path == null || text == null) {
throw new IllegalArgumentException("Path/text cannot be null");
}
if (text.isBlank()) {
return 0;
}
final byte[] texttofind = text.getBytes(StandardCharsets.UTF_8);
long count = 0;
try (FileChannel fileChannel = FileChannel.open(path, StandardOpenOption.READ)) {
long position = 0;
long length = fileChannel.size();
while (position < length) {
long remaining = length - position;
long bytestomap = (long) Math.min(MAP_SIZE, remaining);
MappedByteBuffer mbBuffer = fileChannel.map(MapMode.READ_ONLY, position, bytestomap);
long limit = mbBuffer.limit();
long lastSpace = -1;
long firstChar = -1;
while (mbBuffer.hasRemaining()) {
boolean isFirstChar = false;
while (firstChar != 0 && mbBuffer.hasRemaining()) {
byte currentByte = mbBuffer.get();
if (Character.isWhitespace((char) currentByte)) {
lastSpace = mbBuffer.position();
}
if (texttofind[0] == currentByte) {
isFirstChar = true;
break;
}
}
if (isFirstChar) {
boolean isRestOfChars = true;
int j;
for (j = 1; j < texttofind.length; j++) {
if (!mbBuffer.hasRemaining() || texttofind[j] != mbBuffer.get()) {
isRestOfChars = false;
break;
}
}
if (isRestOfChars) {
count++;
lastSpace = -1;
}
firstChar = -1;
}
}
if (lastSpace > -1) {
position = position - (limit - lastSpace);
}
position += bytestomap;
}
}
return count;
}
Example 20
| Source File: Mismatches.java From Java-Coding-Problems with MIT License | 4 votes |
|
public static boolean haveMismatches(Path p1, Path p2) throws IOException {
if (p1 == null || p2 == null) {
throw new IllegalArgumentException("The given paths cannot be null");
}
try ( FileChannel channel1 = (FileChannel.open(p1,
EnumSet.of(StandardOpenOption.READ)))) {
try ( FileChannel channel2 = (FileChannel.open(p2,
EnumSet.of(StandardOpenOption.READ)))) {
long length1 = channel1.size();
long length2 = channel2.size();
if (length1 != length2) {
return true;
}
int position = 0;
while (position < length1) {
long remaining = length1 - position;
int bytestomap = (int) Math.min(MAP_SIZE, remaining);
MappedByteBuffer mbBuffer1 = channel1.map(
MapMode.READ_ONLY, position, bytestomap);
MappedByteBuffer mbBuffer2 = channel2.map(
MapMode.READ_ONLY, position, bytestomap);
while (mbBuffer1.hasRemaining()) {
if (mbBuffer1.get() != mbBuffer2.get()) {
return true;
}
}
position += bytestomap;
}
}
}
return false;
}
