下面列出了java.io.RandomAccessFile#close ( ) 实例代码，或者点击链接到github查看源代码，也可以在右侧发表评论。
private void saveDataFileHead(MockDataFile mockDataFile, File file) throws Exception {
RandomAccessFile raf = new RandomAccessFile(file, "rw");
//将写文件指针移到文件尾。
raf.seek(raf.length());
raf.writeBytes("\r\n");
raf.writeBytes(Constants.RESPONSE_DATA_DELIMITER);
raf.writeBytes("\r\n");
for (MockData mockData : mockDataFile.getAllMockData()) {
raf.writeBytes(mockData.getDataId()+Constants.RESPONSE_METHOD_DELIMITER);
raf.writeBytes(mockData.getStart()+","+mockData.getEnd());
raf.writeBytes("\r\n");
}
raf.close();
}
public static void printJdpPacket(JdpJmxPacket p) {
if (getVerbose()) {
try {
RandomAccessFile f = new RandomAccessFile("out.dmp", "rw");
f.write(p.getPacketData());
f.close();
} catch (IOException e) {
System.out.println("Can't write a dump file: " + e);
}
System.out.println("Id: " + p.getId());
System.out.println("Jmx: " + p.getJmxServiceUrl());
System.out.println("Main: " + p.getMainClass());
System.out.println("InstanceName: " + p.getInstanceName());
System.out.println("ProccessId: " + p.getProcessId());
System.out.println("BroadcastInterval: " + p.getBroadcastInterval());
System.out.println("Rmi Hostname: " + p.getRmiHostname());
System.out.flush();
}
}
private static void write() throws IOException {
// ��������
RandomAccessFile raf = new RandomAccessFile("raf.txt", "rw");
// ���
raf.writeInt(100);
raf.writeChar('a');
// raf.writeUTF("hello");
raf.writeUTF("����ϼ");
raf.seek(1000);
raf.writeUTF("����");
// �ͷ���Դ
raf.close();
}
@Test
public void testChunkAggregatedUpload() throws IOException {
//create a random file to be uploaded.
int size = 69 * 1024;
File fname = new File(tmpFolder, "testChunkAggregatedUpload.txt");
fname.createNewFile();
RandomAccessFile randf = new RandomAccessFile(fname, "rw");
randf.setLength(size);
randf.close();
//test chunked upload
HttpURLConnection urlConn = request("/test/v1/aggregate/upload", HttpMethod.PUT);
urlConn.setChunkedStreamingMode(1024);
Files.copy(Paths.get(fname.toURI()), urlConn.getOutputStream());
assertEquals(200, urlConn.getResponseCode());
assertEquals(size, Integer.parseInt(getContent(urlConn).split(":")[1].trim()));
urlConn.disconnect();
fname.delete();
}
FileNioMapped(String fileName, String mode) throws IOException {
if ("r".equals(mode)) {
this.mode = MapMode.READ_ONLY;
} else {
this.mode = MapMode.READ_WRITE;
}
this.name = fileName;
logger.debug("create FileNioMapped :" + fileName);
file = new RandomAccessFile(fileName, mode);
try {
reMap();
} catch (IOException e) {
file.close();
file = null;
throw e;
}
}
public FileChange(File file) throws IOException {
if(!file.exists())
{
System.out.println("File not found");
throw new IOException();
}
this.file = file;
RandomAccessFile rsf = new RandomAccessFile(this.file, "rw");
this.data = new byte[(int) rsf.length()];
rsf.read(data);
int pos = 0;
while (pos < data.length) {
instBuf.add(data[pos++]);
}
rsf.close();
getLength();
}
public static void printJdpPacket(JdpJmxPacket p) {
if (getVerbose()) {
try {
RandomAccessFile f = new RandomAccessFile("out.dmp", "rw");
f.write(p.getPacketData());
f.close();
} catch (IOException e) {
System.out.println("Can't write a dump file: " + e);
}
System.out.println("Id: " + p.getId());
System.out.println("Jmx: " + p.getJmxServiceUrl());
System.out.println("Main: " + p.getMainClass());
System.out.println("InstanceName: " + p.getInstanceName());
System.out.println("ProccessId: " + p.getProcessId());
System.out.println("BroadcastInterval: " + p.getBroadcastInterval());
System.out.println("Rmi Hostname: " + p.getRmiHostname());
System.out.flush();
}
}
public TrueTypeCollection( final File filename ) throws IOException {
this.filename = filename;
final RandomAccessFile raf = new RandomAccessFile( filename, "r" );
final byte[] headerBuffer = new byte[ 12 ];
raf.readFully( headerBuffer );
if ( ByteAccessUtilities.readULong( headerBuffer, 0 ) != MAGIC_NUMBER ) {
raf.close();
throw new IOException();
}
numFonts = ByteAccessUtilities.readLong( headerBuffer, 8 );
final byte[] offsetBuffer = new byte[ (int) ( 4 * numFonts ) ];
raf.readFully( offsetBuffer );
final int size = (int) numFonts;
offsets = new long[ size ];
fonts = new TrueTypeFont[ size ];
for ( int i = 0; i < size; i++ ) {
offsets[ i ] = ByteAccessUtilities.readULong( offsetBuffer, i * 4 );
}
}
static LogFile.RandomReader getRandomReader(File file,
@Nullable KeyProvider encryptionKeyProvider)
throws IOException {
RandomAccessFile logFile = new RandomAccessFile(file, "r");
try {
File metaDataFile = Serialization.getMetaDataFile(file);
// either this is a rr for a just created file or
// the metadata file exists and as such it's V3
if(logFile.length() == 0L || metaDataFile.exists()) {
return new LogFileV3.RandomReader(file, encryptionKeyProvider);
}
int version = logFile.readInt();
if(Serialization.VERSION_2 == version) {
return new LogFileV2.RandomReader(file);
}
throw new IOException("File " + file + " has bad version " +
Integer.toHexString(version));
} finally {
if(logFile != null) {
try {
logFile.close();
} catch(IOException e) {
LOGGER.warn("Unable to close " + file, e);
}
}
}
}
public void setLength(long length) throws PersistException {
try {
RandomAccessFile raf = new RandomAccessFile(mFile, "rw");
raf.setLength(length);
raf.close();
} catch (IOException e) {
throw new PersistException(e);
}
}
public int write(AudioInputStream stream, AudioFileFormat.Type fileType, File out) throws IOException {
// throws IllegalArgumentException if not supported
AuFileFormat auFileFormat = (AuFileFormat)getAudioFileFormat(fileType, stream);
// first write the file without worrying about length fields
FileOutputStream fos = new FileOutputStream( out ); // throws IOException
BufferedOutputStream bos = new BufferedOutputStream( fos, bisBufferSize );
int bytesWritten = writeAuFile(stream, auFileFormat, bos );
bos.close();
// now, if length fields were not specified, calculate them,
// open as a random access file, write the appropriate fields,
// close again....
if( auFileFormat.getByteLength()== AudioSystem.NOT_SPECIFIED ) {
// $$kk: 10.22.99: jan: please either implement this or throw an exception!
// $$fb: 2001-07-13: done. Fixes Bug 4479981
RandomAccessFile raf=new RandomAccessFile(out, "rw");
if (raf.length()<=0x7FFFFFFFl) {
// skip AU magic and data offset field
raf.skipBytes(8);
raf.writeInt(bytesWritten-AuFileFormat.AU_HEADERSIZE);
// that's all
}
raf.close();
}
return bytesWritten;
}
@Override
public long open(DataSpec dataSpec) throws EncryptedFileDataSourceException {
try {
uri = dataSpec.uri;
File path = new File(dataSpec.uri.getPath());
String name = path.getName();
File keyPath = new File(FileLoader.getInternalCacheDir(), name + ".key");
RandomAccessFile keyFile = new RandomAccessFile(keyPath, "r");
keyFile.read(key);
keyFile.read(iv);
keyFile.close();
file = new RandomAccessFile(path, "r");
file.seek(dataSpec.position);
fileOffset = (int) dataSpec.position;
bytesRemaining = dataSpec.length == C.LENGTH_UNSET ? file.length() - dataSpec.position : dataSpec.length;
if (bytesRemaining < 0) {
throw new EOFException();
}
} catch (IOException e) {
throw new EncryptedFileDataSourceException(e);
}
opened = true;
transferStarted(dataSpec);
return bytesRemaining;
}
public static void main(String[] args) throws Exception {
RandomAccessFile f = new RandomAccessFile("/Users/zhuam/git/feeyo/feeyoredis/test.txt", "rw");
FileChannel fc = f.getChannel();
MappedByteBuffer buf = fc.map(FileChannel.MapMode.READ_WRITE, 0, fc.size());
while (buf.hasRemaining()) {
System.out.print((char)buf.get());
}
System.out.println();
fc.close();
f.close();
}
/**
* java.io.RandomAccessFile#readInt()
*/
public void test_readInt() throws IOException {
// Test for method int java.io.RandomAccessFile.readInt()
RandomAccessFile raf = new java.io.RandomAccessFile(fileName, "rw");
raf.writeInt(Integer.MIN_VALUE);
raf.seek(0);
assertEquals("Incorrect int read/written", Integer.MIN_VALUE, raf
.readInt());
raf.close();
}
@Override
public int write(AudioInputStream stream, AudioFileFormat.Type fileType, File out) throws IOException {
Objects.requireNonNull(stream);
Objects.requireNonNull(fileType);
Objects.requireNonNull(out);
// throws IllegalArgumentException if not supported
WaveFileFormat waveFileFormat = (WaveFileFormat)getAudioFileFormat(fileType, stream);
// first write the file without worrying about length fields
FileOutputStream fos = new FileOutputStream( out ); // throws IOException
BufferedOutputStream bos = new BufferedOutputStream( fos, bisBufferSize );
int bytesWritten = writeWaveFile(stream, waveFileFormat, bos );
bos.close();
// now, if length fields were not specified, calculate them,
// open as a random access file, write the appropriate fields,
// close again....
if( waveFileFormat.getByteLength()== AudioSystem.NOT_SPECIFIED ) {
int dataLength=bytesWritten-waveFileFormat.getHeaderSize();
int riffLength=dataLength + waveFileFormat.getHeaderSize() - 8;
RandomAccessFile raf=new RandomAccessFile(out, "rw");
// skip RIFF magic
raf.skipBytes(4);
raf.writeInt(big2little( riffLength ));
// skip WAVE magic, fmt_ magic, fmt_ length, fmt_ chunk, data magic
raf.skipBytes(4+4+4+WaveFileFormat.getFmtChunkSize(waveFileFormat.getWaveType())+4);
raf.writeInt(big2little( dataLength ));
// that's all
raf.close();
}
return bytesWritten;
}
@TargetApi(Build.VERSION_CODES.JELLY_BEAN)
private long getSizeTotalRAM(boolean isTotal) {
long sizeInBytes = 1000;
MemoryInfo mi = new MemoryInfo();
activityManager.getMemoryInfo(mi);
if(isTotal) {
try {
if(Utils.hasJellyBean()){
long totalMegs = mi.totalMem;
sizeInBytes = totalMegs;
}
else{
RandomAccessFile reader = new RandomAccessFile("/proc/meminfo", "r");
String load = reader.readLine();
String[] totrm = load.split(" kB");
String[] trm = totrm[0].split(" ");
sizeInBytes=Long.parseLong(trm[trm.length-1]);
sizeInBytes=sizeInBytes*1024;
reader.close();
}
}
catch (Exception e) { }
}
else{
long availableMegs = mi.availMem;
sizeInBytes = availableMegs;
}
return sizeInBytes;
}
public static void main(String[] args) throws Exception {
show(nonExistantFile);
if (nonExistantFile.exists()) fail(nonExistantFile, "exists");
show(rwFile);
testFile(rwFile, true, 6);
rwFile.delete();
if (rwFile.exists())
fail(rwFile, "could not delete");
show(roFile);
testFile(roFile, false, 0);
show(thisDir);
if (!thisDir.exists()) fail(thisDir, "does not exist");
if (thisDir.isFile()) fail(thisDir, "is a file");
if (!thisDir.isDirectory()) fail(thisDir, "is not a directory");
if (!thisDir.canRead()) fail(thisDir, "is readable");
if (!thisDir.canWrite()) fail(thisDir, "is writeable");
String[] fs = thisDir.list();
if (fs == null) fail(thisDir, "list() returned null");
out.print(" [" + fs.length + "]");
for (int i = 0; i < fs.length; i++)
out.print(" " + fs[i]);
out.println();
if (fs.length == 0) fail(thisDir, "is empty");
if (!nonExistantFile.createNewFile())
fail(nonExistantFile, "could not create");
nonExistantFile.deleteOnExit();
if (!nonDir.mkdir())
fail(nonDir, "could not create");
if (!dir.renameTo(new File("x.Basic.dir2")))
fail(dir, "failed to rename");
if (System.getProperty("os.name").equals("SunOS")
&& System.getProperty("os.version").compareTo("5.6") >= 0) {
if (bigFile.exists()) {
bigFile.delete();
if (bigFile.exists())
fail(bigFile, "could not delete");
}
RandomAccessFile raf = new RandomAccessFile(bigFile, "rw");
long big = ((long)Integer.MAX_VALUE) * 2;
try {
raf.seek(big);
raf.write('x');
show(bigFile);
testFile(bigFile, true, big + 1);
} finally {
raf.close();
}
bigFile.delete();
if (bigFile.exists())
fail(bigFile, "could not delete");
} else {
System.err.println("NOTE: Large files not supported on this system");
}
}
@Override
public GridData getGridData_LonLat(int timeIdx, String varName, int levelIdx) {
try {
int xNum, yNum;
xNum = dataHead.NX;
yNum = dataHead.NY;
double[][] theData;
RandomAccessFile br = new RandomAccessFile(this.getFileName(), "r");
byte[] dataBytes;
DataLabel aDL;
//Update level and variable index
Variable aVar = this.getVariable(varName);
if (aVar.getLevelNum() > 1) {
levelIdx += 1;
}
int varIdx = LevelVarList.get(levelIdx).indexOf(aVar.getName());
br.seek(timeIdx * recsPerTime * recLen);
br.seek(br.getFilePointer() + indexLen);
for (int i = 0; i < levelIdx; i++) {
br.seek(br.getFilePointer() + LevelVarList.get(i).size() * recLen);
}
br.seek(br.getFilePointer() + varIdx * recLen);
//Read label
aDL = ARLDataInfo.readDataLabel(br);
//Read Data
dataBytes = new byte[(int)recLen - 50];
br.read(dataBytes);
br.close();
theData = unpackARLGridData(dataBytes, xNum, yNum, aDL);
GridData gridData = new GridData();
gridData.data = theData;
gridData.missingValue = missingValue;
gridData.xArray = X;
gridData.yArray = Y;
return gridData;
} catch (IOException ex) {
Logger.getLogger(ARLDataInfo.class.getName()).log(Level.SEVERE, null, ex);
return null;
}
}
@Override
public GridData getGridData_TimeLat(int lonIdx, String varName, int levelIdx) {
try {
int xNum, yNum, tNum, t;
xNum = dataHead.NX;
yNum = dataHead.NY;
tNum = this.getTimeNum();
double[][] theData;
RandomAccessFile br = new RandomAccessFile(this.getFileName(), "r");
byte[] dataBytes;
DataLabel aDL;
double[][] newGridData = new double[tNum][yNum];
//Update level and variable index
Variable aVar = this.getVariable(varName);
if (aVar.getLevelNum() > 1) {
levelIdx += 1;
}
int varIdx = LevelVarList.get(levelIdx).indexOf(aVar.getName());
for (t = 0; t < tNum; t++) {
br.seek(t * recsPerTime * recLen);
br.seek(br.getFilePointer() + indexLen);
for (int i = 0; i < levelIdx; i++) {
br.seek(br.getFilePointer() + LevelVarList.get(i).size() * recLen);
}
br.seek(br.getFilePointer() + varIdx * recLen);
//Read label
aDL = ARLDataInfo.readDataLabel(br);
//Read Data
dataBytes = new byte[(int)recLen - 50];
br.read(dataBytes);
theData = unpackARLGridData(dataBytes, xNum, yNum, aDL);
for (int i = 0; i < yNum; i++) {
newGridData[t][i] = theData[i][lonIdx];
}
}
br.close();
GridData gridData = new GridData();
gridData.data = newGridData;
gridData.missingValue = missingValue;
gridData.xArray = Y;
gridData.yArray = new double[tNum];
for (int i = 0; i < tNum; i++) {
gridData.yArray[i] = JDateUtil.toOADate(this.getTimes().get(i));
}
return gridData;
} catch (IOException ex) {
Logger.getLogger(ARLDataInfo.class.getName()).log(Level.SEVERE, null, ex);
return null;
}
}
/**
* @param args
*/
public static void main(String[] args) {
// (1). �����ͷ�������Դ�ļ�һ����С�Ŀ��ļ�
try {
// 1. ��ʼ��Url
URL url = new URL(path);
// 2. ͨ��Url��ȡHttp����
HttpURLConnection conn = (HttpURLConnection) url.openConnection();
// 3. �����������������ʽ
conn.setRequestMethod("GET");
// 4. ��ȡ������ 200:�ɹ� 3xxx���� 4xxx�ͻ��˴��� 500����������
int code = conn.getResponseCode();
// 5. �õ��ӷ������˷��ص���Դ�ļ��Ĵ�С
int fileLength = conn.getContentLength();
if (code == 200) {
System.out.println("��������Դ�ļ��Ĵ�С��" + fileLength);
RandomAccessFile raf = new RandomAccessFile(getFileName(), "rw");
// ��Ҫ�����ļ��Ĵ�С
raf.setLength(fileLength);
raf.close();
}
// (2).��������߳�����
// ÿ������Ĵ�С
int blockSize = fileLength / threadCount;
for (int threadId = 0; threadId < threadCount; threadId++) {
int startIndex = threadId * blockSize;
int endIndex = (threadId + 1) * blockSize;
// ���һ���߳�
if (threadId == threadCount - 1) {
// �����ļ�������λ��
endIndex = fileLength - 1;
}
// ��ʼ�߳�
new DownLoadThread(startIndex, endIndex, threadId).start();
}
} catch (Exception e) {
e.printStackTrace();
}
}