下面列出了java.io.DataInputStream#readChar ( ) 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。
public static boolean initialize(Alite alite, final DataInputStream dis) {
InventoryScreen is = new InventoryScreen(alite);
try {
byte selectionLength = dis.readByte();
if (selectionLength > 0) {
is.pendingSelection = "";
while (selectionLength > 0) {
is.pendingSelection += dis.readChar();
selectionLength--;
}
}
} catch (Exception e) {
AliteLog.e("Inventory Screen Initialize", "Error in initializer.", e);
return false;
}
alite.setScreen(is);
return true;
}
/**
* Loads parameter NDArrays from InputStream.
*
* <p>Currently, we cannot deserialize into the exact subclass of NDArray. The SparseNDArray
* will be loaded as NDArray only.
*
* @param manager the NDManager
* @param dis the InputStream
* @throws IOException if failed to read
* @throws MalformedModelException Exception thrown when model is not in expected format
* (parameters).
*/
public void load(NDManager manager, DataInputStream dis)
throws IOException, MalformedModelException {
char magic = dis.readChar();
if (magic == 'N') {
return;
} else if (magic != 'P') {
throw new MalformedModelException("Invalid input data.");
}
// Version
byte version = dis.readByte();
if (version != VERSION) {
throw new MalformedModelException("Unsupported encoding version: " + version);
}
String parameterName = dis.readUTF();
if (!parameterName.equals(getName())) {
throw new MalformedModelException(
"Unexpected parameter name: " + parameterName + ", expected: " + name);
}
array = manager.decode(dis);
}
public static boolean initialize(Alite alite, DataInputStream dis) {
try {
FlightScreen fs = FlightScreen.createScreen(alite, dis);
TutHud th = new TutHud(alite, fs);
th.currentLineIndex = dis.readInt();
th.savedGalaxySeed = new char[3];
th.savedGalaxySeed[0] = dis.readChar();
th.savedGalaxySeed[1] = dis.readChar();
th.savedGalaxySeed[2] = dis.readChar();
alite.getGenerator().buildGalaxy(th.savedGalaxySeed[0], th.savedGalaxySeed[1], th.savedGalaxySeed[2]);
int systemIndex = dis.readInt();
int hyperspaceIndex = dis.readInt();
th.savedPresentSystem = systemIndex == -1 ? null : alite.getGenerator().getSystem(systemIndex);
th.savedHyperspaceSystem = hyperspaceIndex == -1 ? null : alite.getGenerator().getSystem(hyperspaceIndex);
th.savedInstalledEquipment = new ArrayList<Equipment>();
int numEquip = dis.readInt();
for (int i = 0; i < numEquip; i++) {
th.savedInstalledEquipment.add(EquipmentStore.fromInt(dis.readByte()));
}
th.savedFuel = dis.readInt();
for (int i = 0; i < 4; i++) {
int laser = dis.readInt();
th.savedLasers[i] = laser < 0 ? null : (Laser) EquipmentStore.fromInt(laser);
}
for (int i = 0; i < Settings.buttonPosition.length; i++) {
th.savedButtonConfiguration[i] = dis.readInt();
}
th.savedMarketFluct = dis.readInt();
th.savedLegalStatus = LegalStatus.values()[dis.readInt()];
th.savedLegalValue = dis.readInt();
alite.setScreen(th);
} catch (Exception e) {
AliteLog.e("Tutorial HUD Screen Initialize", "Error in initializer.", e);
return false;
}
return true;
}
/**
* <p>Parses the inputstream and creates the trie index with it.</p>
* <p>This is overwritten by the child classes.
* @param inputStream input stream containing the trie information
* @exception IOException thrown when data reading fails.
*/
protected void unserialize(InputStream inputStream) throws IOException
{
//indexLength is a multiple of 1024 >> INDEX_STAGE_2_SHIFT_
m_index_ = new char[m_dataOffset_];
DataInputStream input = new DataInputStream(inputStream);
for (int i = 0; i < m_dataOffset_; i ++) {
m_index_[i] = input.readChar();
}
}
/**
* <p>Parses the input stream and stores its trie content into a index and
* data array</p>
* @param inputStream data input stream containing trie data
* @exception IOException thrown when data reading fails
*/
protected final void unserialize(InputStream inputStream)
throws IOException
{
DataInputStream input = new DataInputStream(inputStream);
int indexDataLength = m_dataOffset_ + m_dataLength_;
m_index_ = new char[indexDataLength];
for (int i = 0; i < indexDataLength; i ++) {
m_index_[i] = input.readChar();
}
m_data_ = m_index_;
m_initialValue_ = m_data_[m_dataOffset_];
}
/**
* <p>Parses the inputstream and creates the trie index with it.</p>
* <p>This is overwritten by the child classes.
* @param inputStream input stream containing the trie information
* @exception IOException thrown when data reading fails.
*/
protected void unserialize(InputStream inputStream) throws IOException
{
//indexLength is a multiple of 1024 >> INDEX_STAGE_2_SHIFT_
m_index_ = new char[m_dataOffset_];
DataInputStream input = new DataInputStream(inputStream);
for (int i = 0; i < m_dataOffset_; i ++) {
m_index_[i] = input.readChar();
}
}
/**
* <p>Parses the input stream and stores its trie content into a index and
* data array</p>
* @param inputStream data input stream containing trie data
* @exception IOException thrown when data reading fails
*/
protected final void unserialize(InputStream inputStream)
throws IOException
{
DataInputStream input = new DataInputStream(inputStream);
int indexDataLength = m_dataOffset_ + m_dataLength_;
m_index_ = new char[indexDataLength];
for (int i = 0; i < indexDataLength; i ++) {
m_index_[i] = input.readChar();
}
m_data_ = m_index_;
m_initialValue_ = m_data_[m_dataOffset_];
}
/**
* <p>Parses the inputstream and creates the trie index with it.</p>
* <p>This is overwritten by the child classes.
* @param inputStream input stream containing the trie information
* @exception IOException thrown when data reading fails.
*/
protected void unserialize(InputStream inputStream) throws IOException
{
//indexLength is a multiple of 1024 >> INDEX_STAGE_2_SHIFT_
m_index_ = new char[m_dataOffset_];
DataInputStream input = new DataInputStream(inputStream);
for (int i = 0; i < m_dataOffset_; i ++) {
m_index_[i] = input.readChar();
}
}
@Override
public void load(DataInputStream dis) throws IOException {
galaxySeed = new char[3];
galaxySeed[0] = dis.readChar();
galaxySeed[1] = dis.readChar();
galaxySeed[2] = dis.readChar();
targetIndex = dis.readInt();
state = dis.readInt();
active = true;
started = true;
}
@Override
public void load(DataInputStream dis) throws IOException {
galaxySeed = new char[3];
galaxySeed[0] = dis.readChar();
galaxySeed[1] = dis.readChar();
galaxySeed[2] = dis.readChar();
supernovaSystemIndex = dis.readInt();
state = dis.readInt();
active = true;
started = true;
}
@Override
public void load(DataInputStream dis) throws IOException {
galaxySeed = new char[3];
galaxySeed[0] = dis.readChar();
galaxySeed[1] = dis.readChar();
galaxySeed[2] = dis.readChar();
targetIndex = dis.readInt();
state = dis.readInt();
resetTargetName();
active = true;
started = true;
}
/**
* <p>Parses the inputstream and creates the trie index with it.</p>
* <p>This is overwritten by the child classes.
* @param inputStream input stream containing the trie information
* @exception IOException thrown when data reading fails.
*/
protected void unserialize(InputStream inputStream) throws IOException
{
//indexLength is a multiple of 1024 >> INDEX_STAGE_2_SHIFT_
m_index_ = new char[m_dataOffset_];
DataInputStream input = new DataInputStream(inputStream);
for (int i = 0; i < m_dataOffset_; i ++) {
m_index_[i] = input.readChar();
}
}
@Override
public void load(DataInputStream dis) throws IOException {
galaxySeed = new char[3];
galaxySeed[0] = dis.readChar();
galaxySeed[1] = dis.readChar();
galaxySeed[2] = dis.readChar();
targetIndex = dis.readInt();
state = dis.readInt();
resetTargetName();
active = true;
started = true;
}
public static final byte[] readHeader(InputStream inputStream,
byte dataFormatIDExpected[],
Authenticate authenticate)
throws IOException
{
DataInputStream input = new DataInputStream(inputStream);
char headersize = input.readChar();
int readcount = 2;
//reading the header format
byte magic1 = input.readByte();
readcount ++;
byte magic2 = input.readByte();
readcount ++;
if (magic1 != MAGIC1 || magic2 != MAGIC2) {
throw new IOException(MAGIC_NUMBER_AUTHENTICATION_FAILED_);
}
input.readChar(); // reading size
readcount += 2;
input.readChar(); // reading reserved word
readcount += 2;
byte bigendian = input.readByte();
readcount ++;
byte charset = input.readByte();
readcount ++;
byte charsize = input.readByte();
readcount ++;
input.readByte(); // reading reserved byte
readcount ++;
byte dataFormatID[] = new byte[4];
input.readFully(dataFormatID);
readcount += 4;
byte dataVersion[] = new byte[4];
input.readFully(dataVersion);
readcount += 4;
byte unicodeVersion[] = new byte[4];
input.readFully(unicodeVersion);
readcount += 4;
if (headersize < readcount) {
throw new IOException("Internal Error: Header size error");
}
input.skipBytes(headersize - readcount);
if (bigendian != BIG_ENDIAN_ || charset != CHAR_SET_
|| charsize != CHAR_SIZE_
|| !Arrays.equals(dataFormatIDExpected, dataFormatID)
|| (authenticate != null
&& !authenticate.isDataVersionAcceptable(dataVersion))) {
throw new IOException(HEADER_AUTHENTICATION_FAILED_);
}
return unicodeVersion;
}
/**
* <p>ICU data header reader method.
* Takes a ICU generated big-endian input stream, parse the ICU standard
* file header and authenticates them.</p>
* <p>Header format:
* <ul>
* <li> Header size (char)
* <li> Magic number 1 (byte)
* <li> Magic number 2 (byte)
* <li> Rest of the header size (char)
* <li> Reserved word (char)
* <li> Big endian indicator (byte)
* <li> Character set family indicator (byte)
* <li> Size of a char (byte) for c++ and c use
* <li> Reserved byte (byte)
* <li> Data format identifier (4 bytes), each ICU data has its own
* identifier to distinguish them. [0] major [1] minor
* [2] milli [3] micro
* <li> Data version (4 bytes), the change version of the ICU data
* [0] major [1] minor [2] milli [3] micro
* <li> Unicode version (4 bytes) this ICU is based on.
* </ul>
* </p>
* <p>
* Example of use:<br>
* <pre>
* try {
* FileInputStream input = new FileInputStream(filename);
* If (Utility.readICUDataHeader(input, dataformat, dataversion,
* unicode) {
* System.out.println("Verified file header, this is a ICU data file");
* }
* } catch (IOException e) {
* System.out.println("This is not a ICU data file");
* }
* </pre>
* </p>
* @param inputStream input stream that contains the ICU data header
* @param dataFormatIDExpected Data format expected. An array of 4 bytes
* information about the data format.
* E.g. data format ID 1.2.3.4. will became an array of
* {1, 2, 3, 4}
* @param authenticate user defined extra data authentication. This value
* can be null, if no extra authentication is needed.
* @exception IOException thrown if there is a read error or
* when header authentication fails.
* @draft 2.1
*/
public static final byte[] readHeader(InputStream inputStream,
byte dataFormatIDExpected[],
Authenticate authenticate)
throws IOException
{
DataInputStream input = new DataInputStream(inputStream);
char headersize = input.readChar();
int readcount = 2;
//reading the header format
byte magic1 = input.readByte();
readcount ++;
byte magic2 = input.readByte();
readcount ++;
if (magic1 != MAGIC1 || magic2 != MAGIC2) {
throw new IOException(MAGIC_NUMBER_AUTHENTICATION_FAILED_);
}
input.readChar(); // reading size
readcount += 2;
input.readChar(); // reading reserved word
readcount += 2;
byte bigendian = input.readByte();
readcount ++;
byte charset = input.readByte();
readcount ++;
byte charsize = input.readByte();
readcount ++;
input.readByte(); // reading reserved byte
readcount ++;
byte dataFormatID[] = new byte[4];
input.readFully(dataFormatID);
readcount += 4;
byte dataVersion[] = new byte[4];
input.readFully(dataVersion);
readcount += 4;
byte unicodeVersion[] = new byte[4];
input.readFully(unicodeVersion);
readcount += 4;
if (headersize < readcount) {
throw new IOException("Internal Error: Header size error");
}
input.skipBytes(headersize - readcount);
if (bigendian != BIG_ENDIAN_ || charset != CHAR_SET_
|| charsize != CHAR_SIZE_
|| !Arrays.equals(dataFormatIDExpected, dataFormatID)
|| (authenticate != null
&& !authenticate.isDataVersionAcceptable(dataVersion))) {
throw new IOException(HEADER_AUTHENTICATION_FAILED_);
}
return unicodeVersion;
}
public static final byte[] readHeader(InputStream inputStream,
byte dataFormatIDExpected[],
Authenticate authenticate)
throws IOException
{
DataInputStream input = new DataInputStream(inputStream);
char headersize = input.readChar();
int readcount = 2;
//reading the header format
byte magic1 = input.readByte();
readcount ++;
byte magic2 = input.readByte();
readcount ++;
if (magic1 != MAGIC1 || magic2 != MAGIC2) {
throw new IOException(MAGIC_NUMBER_AUTHENTICATION_FAILED_);
}
input.readChar(); // reading size
readcount += 2;
input.readChar(); // reading reserved word
readcount += 2;
byte bigendian = input.readByte();
readcount ++;
byte charset = input.readByte();
readcount ++;
byte charsize = input.readByte();
readcount ++;
input.readByte(); // reading reserved byte
readcount ++;
byte dataFormatID[] = new byte[4];
input.readFully(dataFormatID);
readcount += 4;
byte dataVersion[] = new byte[4];
input.readFully(dataVersion);
readcount += 4;
byte unicodeVersion[] = new byte[4];
input.readFully(unicodeVersion);
readcount += 4;
if (headersize < readcount) {
throw new IOException("Internal Error: Header size error");
}
input.skipBytes(headersize - readcount);
if (bigendian != BIG_ENDIAN_ || charset != CHAR_SET_
|| charsize != CHAR_SIZE_
|| !Arrays.equals(dataFormatIDExpected, dataFormatID)
|| (authenticate != null
&& !authenticate.isDataVersionAcceptable(dataVersion))) {
throw new IOException(HEADER_AUTHENTICATION_FAILED_);
}
return unicodeVersion;
}
/**
* <p>ICU data header reader method.
* Takes a ICU generated big-endian input stream, parse the ICU standard
* file header and authenticates them.</p>
* <p>Header format:
* <ul>
* <li> Header size (char)
* <li> Magic number 1 (byte)
* <li> Magic number 2 (byte)
* <li> Rest of the header size (char)
* <li> Reserved word (char)
* <li> Big endian indicator (byte)
* <li> Character set family indicator (byte)
* <li> Size of a char (byte) for c++ and c use
* <li> Reserved byte (byte)
* <li> Data format identifier (4 bytes), each ICU data has its own
* identifier to distinguish them. [0] major [1] minor
* [2] milli [3] micro
* <li> Data version (4 bytes), the change version of the ICU data
* [0] major [1] minor [2] milli [3] micro
* <li> Unicode version (4 bytes) this ICU is based on.
* </ul>
* </p>
* <p>
* Example of use:<br>
* <pre>
* try {
* FileInputStream input = new FileInputStream(filename);
* If (Utility.readICUDataHeader(input, dataformat, dataversion,
* unicode) {
* System.out.println("Verified file header, this is a ICU data file");
* }
* } catch (IOException e) {
* System.out.println("This is not a ICU data file");
* }
* </pre>
* </p>
* @param inputStream input stream that contains the ICU data header
* @param dataFormatIDExpected Data format expected. An array of 4 bytes
* information about the data format.
* E.g. data format ID 1.2.3.4. will became an array of
* {1, 2, 3, 4}
* @param authenticate user defined extra data authentication. This value
* can be null, if no extra authentication is needed.
* @exception IOException thrown if there is a read error or
* when header authentication fails.
* @draft 2.1
*/
public static final byte[] readHeader(InputStream inputStream,
byte dataFormatIDExpected[],
Authenticate authenticate)
throws IOException
{
DataInputStream input = new DataInputStream(inputStream);
char headersize = input.readChar();
int readcount = 2;
//reading the header format
byte magic1 = input.readByte();
readcount ++;
byte magic2 = input.readByte();
readcount ++;
if (magic1 != MAGIC1 || magic2 != MAGIC2) {
throw new IOException(MAGIC_NUMBER_AUTHENTICATION_FAILED_);
}
input.readChar(); // reading size
readcount += 2;
input.readChar(); // reading reserved word
readcount += 2;
byte bigendian = input.readByte();
readcount ++;
byte charset = input.readByte();
readcount ++;
byte charsize = input.readByte();
readcount ++;
input.readByte(); // reading reserved byte
readcount ++;
byte dataFormatID[] = new byte[4];
input.readFully(dataFormatID);
readcount += 4;
byte dataVersion[] = new byte[4];
input.readFully(dataVersion);
readcount += 4;
byte unicodeVersion[] = new byte[4];
input.readFully(unicodeVersion);
readcount += 4;
if (headersize < readcount) {
throw new IOException("Internal Error: Header size error");
}
input.skipBytes(headersize - readcount);
if (bigendian != BIG_ENDIAN_ || charset != CHAR_SET_
|| charsize != CHAR_SIZE_
|| !Arrays.equals(dataFormatIDExpected, dataFormatID)
|| (authenticate != null
&& !authenticate.isDataVersionAcceptable(dataVersion))) {
throw new IOException(HEADER_AUTHENTICATION_FAILED_);
}
return unicodeVersion;
}
/**
* <p>ICU data header reader method.
* Takes a ICU generated big-endian input stream, parse the ICU standard
* file header and authenticates them.</p>
* <p>Header format:
* <ul>
* <li> Header size (char)
* <li> Magic number 1 (byte)
* <li> Magic number 2 (byte)
* <li> Rest of the header size (char)
* <li> Reserved word (char)
* <li> Big endian indicator (byte)
* <li> Character set family indicator (byte)
* <li> Size of a char (byte) for c++ and c use
* <li> Reserved byte (byte)
* <li> Data format identifier (4 bytes), each ICU data has its own
* identifier to distinguish them. [0] major [1] minor
* [2] milli [3] micro
* <li> Data version (4 bytes), the change version of the ICU data
* [0] major [1] minor [2] milli [3] micro
* <li> Unicode version (4 bytes) this ICU is based on.
* </ul>
* </p>
* <p>
* Example of use:<br>
* <pre>
* try {
* FileInputStream input = new FileInputStream(filename);
* If (Utility.readICUDataHeader(input, dataformat, dataversion,
* unicode) {
* System.out.println("Verified file header, this is a ICU data file");
* }
* } catch (IOException e) {
* System.out.println("This is not a ICU data file");
* }
* </pre>
* </p>
* @param inputStream input stream that contains the ICU data header
* @param dataFormatIDExpected Data format expected. An array of 4 bytes
* information about the data format.
* E.g. data format ID 1.2.3.4. will became an array of
* {1, 2, 3, 4}
* @param authenticate user defined extra data authentication. This value
* can be null, if no extra authentication is needed.
* @exception IOException thrown if there is a read error or
* when header authentication fails.
* @draft 2.1
*/
public static final byte[] readHeader(InputStream inputStream,
byte dataFormatIDExpected[],
Authenticate authenticate)
throws IOException
{
DataInputStream input = new DataInputStream(inputStream);
char headersize = input.readChar();
int readcount = 2;
//reading the header format
byte magic1 = input.readByte();
readcount ++;
byte magic2 = input.readByte();
readcount ++;
if (magic1 != MAGIC1 || magic2 != MAGIC2) {
throw new IOException(MAGIC_NUMBER_AUTHENTICATION_FAILED_);
}
input.readChar(); // reading size
readcount += 2;
input.readChar(); // reading reserved word
readcount += 2;
byte bigendian = input.readByte();
readcount ++;
byte charset = input.readByte();
readcount ++;
byte charsize = input.readByte();
readcount ++;
input.readByte(); // reading reserved byte
readcount ++;
byte dataFormatID[] = new byte[4];
input.readFully(dataFormatID);
readcount += 4;
byte dataVersion[] = new byte[4];
input.readFully(dataVersion);
readcount += 4;
byte unicodeVersion[] = new byte[4];
input.readFully(unicodeVersion);
readcount += 4;
if (headersize < readcount) {
throw new IOException("Internal Error: Header size error");
}
input.skipBytes(headersize - readcount);
if (bigendian != BIG_ENDIAN_ || charset != CHAR_SET_
|| charsize != CHAR_SIZE_
|| !Arrays.equals(dataFormatIDExpected, dataFormatID)
|| (authenticate != null
&& !authenticate.isDataVersionAcceptable(dataVersion))) {
throw new IOException(HEADER_AUTHENTICATION_FAILED_);
}
return unicodeVersion;
}
/**
* <p>ICU data header reader method.
* Takes a ICU generated big-endian input stream, parse the ICU standard
* file header and authenticates them.</p>
* <p>Header format:
* <ul>
* <li> Header size (char)
* <li> Magic number 1 (byte)
* <li> Magic number 2 (byte)
* <li> Rest of the header size (char)
* <li> Reserved word (char)
* <li> Big endian indicator (byte)
* <li> Character set family indicator (byte)
* <li> Size of a char (byte) for c++ and c use
* <li> Reserved byte (byte)
* <li> Data format identifier (4 bytes), each ICU data has its own
* identifier to distinguish them. [0] major [1] minor
* [2] milli [3] micro
* <li> Data version (4 bytes), the change version of the ICU data
* [0] major [1] minor [2] milli [3] micro
* <li> Unicode version (4 bytes) this ICU is based on.
* </ul>
* </p>
* <p>
* Example of use:<br>
* <pre>
* try {
* FileInputStream input = new FileInputStream(filename);
* If (Utility.readICUDataHeader(input, dataformat, dataversion,
* unicode) {
* System.out.println("Verified file header, this is a ICU data file");
* }
* } catch (IOException e) {
* System.out.println("This is not a ICU data file");
* }
* </pre>
* </p>
* @param inputStream input stream that contains the ICU data header
* @param dataFormatIDExpected Data format expected. An array of 4 bytes
* information about the data format.
* E.g. data format ID 1.2.3.4. will became an array of
* {1, 2, 3, 4}
* @param authenticate user defined extra data authentication. This value
* can be null, if no extra authentication is needed.
* @exception IOException thrown if there is a read error or
* when header authentication fails.
* @draft 2.1
*/
public static final byte[] readHeader(InputStream inputStream,
byte dataFormatIDExpected[],
Authenticate authenticate)
throws IOException
{
DataInputStream input = new DataInputStream(inputStream);
char headersize = input.readChar();
int readcount = 2;
//reading the header format
byte magic1 = input.readByte();
readcount ++;
byte magic2 = input.readByte();
readcount ++;
if (magic1 != MAGIC1 || magic2 != MAGIC2) {
throw new IOException(MAGIC_NUMBER_AUTHENTICATION_FAILED_);
}
input.readChar(); // reading size
readcount += 2;
input.readChar(); // reading reserved word
readcount += 2;
byte bigendian = input.readByte();
readcount ++;
byte charset = input.readByte();
readcount ++;
byte charsize = input.readByte();
readcount ++;
input.readByte(); // reading reserved byte
readcount ++;
byte dataFormatID[] = new byte[4];
input.readFully(dataFormatID);
readcount += 4;
byte dataVersion[] = new byte[4];
input.readFully(dataVersion);
readcount += 4;
byte unicodeVersion[] = new byte[4];
input.readFully(unicodeVersion);
readcount += 4;
if (headersize < readcount) {
throw new IOException("Internal Error: Header size error");
}
input.skipBytes(headersize - readcount);
if (bigendian != BIG_ENDIAN_ || charset != CHAR_SET_
|| charsize != CHAR_SIZE_
|| !Arrays.equals(dataFormatIDExpected, dataFormatID)
|| (authenticate != null
&& !authenticate.isDataVersionAcceptable(dataVersion))) {
throw new IOException(HEADER_AUTHENTICATION_FAILED_);
}
return unicodeVersion;
}
/**
* <p>ICU data header reader method.
* Takes a ICU generated big-endian input stream, parse the ICU standard
* file header and authenticates them.</p>
* <p>Header format:
* <ul>
* <li> Header size (char)
* <li> Magic number 1 (byte)
* <li> Magic number 2 (byte)
* <li> Rest of the header size (char)
* <li> Reserved word (char)
* <li> Big endian indicator (byte)
* <li> Character set family indicator (byte)
* <li> Size of a char (byte) for c++ and c use
* <li> Reserved byte (byte)
* <li> Data format identifier (4 bytes), each ICU data has its own
* identifier to distinguish them. [0] major [1] minor
* [2] milli [3] micro
* <li> Data version (4 bytes), the change version of the ICU data
* [0] major [1] minor [2] milli [3] micro
* <li> Unicode version (4 bytes) this ICU is based on.
* </ul>
* </p>
* <p>
* Example of use:<br>
* <pre>
* try {
* FileInputStream input = new FileInputStream(filename);
* If (Utility.readICUDataHeader(input, dataformat, dataversion,
* unicode) {
* System.out.println("Verified file header, this is a ICU data file");
* }
* } catch (IOException e) {
* System.out.println("This is not a ICU data file");
* }
* </pre>
* </p>
* @param inputStream input stream that contains the ICU data header
* @param dataFormatIDExpected Data format expected. An array of 4 bytes
* information about the data format.
* E.g. data format ID 1.2.3.4. will became an array of
* {1, 2, 3, 4}
* @param authenticate user defined extra data authentication. This value
* can be null, if no extra authentication is needed.
* @exception IOException thrown if there is a read error or
* when header authentication fails.
* @draft 2.1
*/
public static final byte[] readHeader(InputStream inputStream,
byte dataFormatIDExpected[],
Authenticate authenticate)
throws IOException
{
DataInputStream input = new DataInputStream(inputStream);
char headersize = input.readChar();
int readcount = 2;
//reading the header format
byte magic1 = input.readByte();
readcount ++;
byte magic2 = input.readByte();
readcount ++;
if (magic1 != MAGIC1 || magic2 != MAGIC2) {
throw new IOException(MAGIC_NUMBER_AUTHENTICATION_FAILED_);
}
input.readChar(); // reading size
readcount += 2;
input.readChar(); // reading reserved word
readcount += 2;
byte bigendian = input.readByte();
readcount ++;
byte charset = input.readByte();
readcount ++;
byte charsize = input.readByte();
readcount ++;
input.readByte(); // reading reserved byte
readcount ++;
byte dataFormatID[] = new byte[4];
input.readFully(dataFormatID);
readcount += 4;
byte dataVersion[] = new byte[4];
input.readFully(dataVersion);
readcount += 4;
byte unicodeVersion[] = new byte[4];
input.readFully(unicodeVersion);
readcount += 4;
if (headersize < readcount) {
throw new IOException("Internal Error: Header size error");
}
input.skipBytes(headersize - readcount);
if (bigendian != BIG_ENDIAN_ || charset != CHAR_SET_
|| charsize != CHAR_SIZE_
|| !Arrays.equals(dataFormatIDExpected, dataFormatID)
|| (authenticate != null
&& !authenticate.isDataVersionAcceptable(dataVersion))) {
throw new IOException(HEADER_AUTHENTICATION_FAILED_);
}
return unicodeVersion;
}