Field Summary

Constructor Summary

Method Summary

Constructor Details

• DataInputStream

  public DataInputStream(InputStream in)

  Creates a DataInputStream that uses the specified underlying InputStream.

  Parameters:

  in - the specified input stream

Method Details

• read

  public final int read(byte[] b) throwsIOException

  Reads some number of bytes from the contained input stream and stores them into the buffer arrayb. The number of bytes actually read is returned as an integer. This method blocks until input data is available, end of file is detected, or an exception is thrown.

  Ifb is null, aNullPointerException is thrown. If the length ofb is zero, then no bytes are read and0 is returned; otherwise, there is an attempt to read at least one byte. If no byte is available because the stream is at end of file, the value-1 is returned; otherwise, at least one byte is read and stored intob.

  The first byte read is stored into elementb[0], the next one intob[1], and so on. The number of bytes read is, at most, equal to the length ofb. Letk be the number of bytes actually read; these bytes will be stored in elementsb[0] throughb[k-1], leaving elementsb[k] throughb[b.length-1] unaffected.

  Theread(b) method has the same effect as:

   read(b, 0, b.length)

  Overrides:

  read in class FilterInputStream

  Parameters:

  b - the buffer into which the data is read.

  Returns:

  the total number of bytes read into the buffer, or-1 if there is no more data because the end of the stream has been reached.

  Throws:

  IOException - if the first byte cannot be read for any reason other than end of file, the stream has been closed and the underlying input stream does not support reading after close, or another I/O error occurs.

  See Also:

  • FilterInputStream.in
  • InputStream.read(byte[], int, int)

• read

  public final int read(byte[] b, int off, int len) throwsIOException

  Reads up tolen bytes of data from the contained input stream into an array of bytes. An attempt is made to read as many aslen bytes, but a smaller number may be read, possibly zero. The number of bytes actually read is returned as an integer.

  This method blocks until input data is available, end of file is detected, or an exception is thrown.

  Iflen is zero, then no bytes are read and0 is returned; otherwise, there is an attempt to read at least one byte. If no byte is available because the stream is at end of file, the value-1 is returned; otherwise, at least one byte is read and stored intob.

  The first byte read is stored into elementb[off], the next one intob[off+1], and so on. The number of bytes read is, at most, equal tolen. Letk be the number of bytes actually read; these bytes will be stored in elementsb[off] throughb[off+k-1], leaving elementsb[off+k] throughb[off+len-1] unaffected.

  In every case, elementsb[0] throughb[off] and elementsb[off+len] throughb[b.length-1] are unaffected.

  Overrides:

  read in class FilterInputStream

  Parameters:

  b - the buffer into which the data is read.

  off - the start offset in the destination arrayb

  len - the maximum number of bytes read.

  Returns:

  the total number of bytes read into the buffer, or-1 if there is no more data because the end of the stream has been reached.

  Throws:

  NullPointerException - Ifb isnull.

  IndexOutOfBoundsException - Ifoff is negative,len is negative, orlen is greater thanb.length - off

  IOException - if the first byte cannot be read for any reason other than end of file, the stream has been closed and the underlying input stream does not support reading after close, or another I/O error occurs.

  See Also:

  • FilterInputStream.in
  • InputStream.read(byte[], int, int)

• readFully

  public final void readFully(byte[] b) throwsIOException

  See the general contract of thereadFully method ofDataInput.

  Bytes for this operation are read from the contained input stream.

  Specified by:

  readFully in interface DataInput

  Parameters:

  b - the buffer into which the data is read.

  Throws:

  NullPointerException - ifb isnull.

  EOFException - if this input stream reaches the end before reading all the bytes.

  IOException - the stream has been closed and the contained input stream does not support reading after close, or another I/O error occurs.

  See Also:

  • FilterInputStream.in

• readFully

  public final void readFully(byte[] b, int off, int len) throwsIOException

  See the general contract of thereadFully method ofDataInput.

  Bytes for this operation are read from the contained input stream.

  Specified by:

  readFully in interface DataInput

  Parameters:

  b - the buffer into which the data is read.

  off - the start offset in the data arrayb.

  len - the number of bytes to read.

  Throws:

  NullPointerException - ifb isnull.

  IndexOutOfBoundsException - ifoff is negative,len is negative, orlen is greater thanb.length - off.

  EOFException - if this input stream reaches the end before reading all the bytes.

  IOException - the stream has been closed and the contained input stream does not support reading after close, or another I/O error occurs.

  See Also:

  • FilterInputStream.in

• skipBytes

  public final int skipBytes(int n) throwsIOException

  See the general contract of theskipBytes method ofDataInput.

  Bytes for this operation are read from the contained input stream.

  Specified by:

  skipBytes in interface DataInput

  Parameters:

  n - the number of bytes to be skipped.

  Returns:

  the actual number of bytes skipped.

  Throws:

  IOException - if the contained input stream does not support seek, or the stream has been closed and the contained input stream does not support reading after close, or another I/O error occurs.

• readBoolean

  public final boolean readBoolean() throwsIOException

  See the general contract of thereadBoolean method ofDataInput.

  Bytes for this operation are read from the contained input stream.

  Specified by:

  readBoolean in interface DataInput

  Returns:

  theboolean value read.

  Throws:

  EOFException - if this input stream has reached the end.

  IOException - the stream has been closed and the contained input stream does not support reading after close, or another I/O error occurs.

  See Also:

  • FilterInputStream.in

• readByte

  public final byte readByte() throwsIOException

  See the general contract of thereadByte method ofDataInput.

  Bytes for this operation are read from the contained input stream.

  Specified by:

  readByte in interface DataInput

  Returns:

  the next byte of this input stream as a signed 8-bitbyte.

  Throws:

  EOFException - if this input stream has reached the end.

  IOException - the stream has been closed and the contained input stream does not support reading after close, or another I/O error occurs.

  See Also:

  • FilterInputStream.in

• readUnsignedByte

  public final int readUnsignedByte() throwsIOException

  See the general contract of thereadUnsignedByte method ofDataInput.

  Bytes for this operation are read from the contained input stream.

  Specified by:

  readUnsignedByte in interface DataInput

  Returns:

  the next byte of this input stream, interpreted as an unsigned 8-bit number.

  Throws:

  EOFException - if this input stream has reached the end.

  IOException - the stream has been closed and the contained input stream does not support reading after close, or another I/O error occurs.

  See Also:

  • FilterInputStream.in

• readShort

  public final short readShort() throwsIOException

  See the general contract of thereadShort method ofDataInput.

  Bytes for this operation are read from the contained input stream.

  Specified by:

  readShort in interface DataInput

  Returns:

  the next two bytes of this input stream, interpreted as a signed 16-bit number.

  Throws:

  EOFException - if this input stream reaches the end before reading two bytes.

  IOException - the stream has been closed and the contained input stream does not support reading after close, or another I/O error occurs.

  See Also:

  • FilterInputStream.in

• readUnsignedShort

  public final int readUnsignedShort() throwsIOException

  See the general contract of thereadUnsignedShort method ofDataInput.

  Bytes for this operation are read from the contained input stream.

  Specified by:

  readUnsignedShort in interface DataInput

  Returns:

  the next two bytes of this input stream, interpreted as an unsigned 16-bit integer.

  Throws:

  EOFException - if this input stream reaches the end before reading two bytes.

  IOException - the stream has been closed and the contained input stream does not support reading after close, or another I/O error occurs.

  See Also:

  • FilterInputStream.in

• readChar

  public final char readChar() throwsIOException

  See the general contract of thereadChar method ofDataInput.

  Bytes for this operation are read from the contained input stream.

  Specified by:

  readChar in interface DataInput

  Returns:

  the next two bytes of this input stream, interpreted as achar.

  Throws:

  EOFException - if this input stream reaches the end before reading two bytes.

  IOException - the stream has been closed and the contained input stream does not support reading after close, or another I/O error occurs.

  See Also:

  • FilterInputStream.in

• readInt

  public final int readInt() throwsIOException

  See the general contract of thereadInt method ofDataInput.

  Bytes for this operation are read from the contained input stream.

  Specified by:

  readInt in interface DataInput

  Returns:

  the next four bytes of this input stream, interpreted as anint.

  Throws:

  EOFException - if this input stream reaches the end before reading four bytes.

  IOException - the stream has been closed and the contained input stream does not support reading after close, or another I/O error occurs.

  See Also:

  • FilterInputStream.in

• readLong

  public final long readLong() throwsIOException

  See the general contract of thereadLong method ofDataInput.

  Bytes for this operation are read from the contained input stream.

  Specified by:

  readLong in interface DataInput

  Returns:

  the next eight bytes of this input stream, interpreted as along.

  Throws:

  EOFException - if this input stream reaches the end before reading eight bytes.

  IOException - the stream has been closed and the contained input stream does not support reading after close, or another I/O error occurs.

  See Also:

  • FilterInputStream.in

• readFloat

  public final float readFloat() throwsIOException

  See the general contract of thereadFloat method ofDataInput.

  Bytes for this operation are read from the contained input stream.

  Specified by:

  readFloat in interface DataInput

  Returns:

  the next four bytes of this input stream, interpreted as afloat.

  Throws:

  EOFException - if this input stream reaches the end before reading four bytes.

  IOException - the stream has been closed and the contained input stream does not support reading after close, or another I/O error occurs.

  See Also:

  • readInt()
  • Float.intBitsToFloat(int)

• readDouble

  public final double readDouble() throwsIOException

  See the general contract of thereadDouble method ofDataInput.

  Bytes for this operation are read from the contained input stream.

  Specified by:

  readDouble in interface DataInput

  Returns:

  the next eight bytes of this input stream, interpreted as adouble.

  Throws:

  EOFException - if this input stream reaches the end before reading eight bytes.

  IOException - the stream has been closed and the contained input stream does not support reading after close, or another I/O error occurs.

  See Also:

  • readLong()
  • Double.longBitsToDouble(long)

• readLine

  @Deprecatedpublic final String readLine() throwsIOException

  Deprecated.

  This method does not properly convert bytes to characters. As of JDK 1.1, the preferred way to read lines of text is via theBufferedReader.readLine() method. Programs that use theDataInputStream class to read lines can be converted to use theBufferedReader class by replacing code of the form:

       DataInputStream d = new DataInputStream(in);

  with:

       BufferedReader d          = new BufferedReader(new InputStreamReader(in));

  See the general contract of thereadLine method ofDataInput.

  Bytes for this operation are read from the contained input stream.

  Specified by:

  readLine in interface DataInput

  Returns:

  the next line of text from this input stream.

  Throws:

  IOException - if an I/O error occurs.

  See Also:

  • BufferedReader.readLine()
  • FilterInputStream.in

• readUTF

  public final String readUTF() throwsIOException

  See the general contract of thereadUTF method ofDataInput.

  Bytes for this operation are read from the contained input stream.

  Specified by:

  readUTF in interface DataInput

  Returns:

  a Unicode string.

  Throws:

  EOFException - if this input stream reaches the end before reading all the bytes.

  IOException - the stream has been closed and the contained input stream does not support reading after close, or another I/O error occurs.

  UTFDataFormatException - if the bytes do not represent a valid modified UTF-8 encoding of a string.

  See Also:

  • readUTF(java.io.DataInput)

• readUTF

  public static final String readUTF(DataInput in) throwsIOException

  Reads from the streamin a representation of a Unicode character string encoded inmodified UTF-8 format; this string of characters is then returned as aString. The details of the modified UTF-8 representation are exactly the same as for thereadUTF method ofDataInput.

  Parameters:

  in - a data input stream.

  Returns:

  a Unicode string.

  Throws:

  EOFException - if the input stream reaches the end before all the bytes.

  IOException - the stream has been closed and the contained input stream does not support reading after close, or another I/O error occurs.

  UTFDataFormatException - if the bytes do not represent a valid modified UTF-8 encoding of a Unicode string.

  See Also:

  • readUnsignedShort()