1. Description
2. Field Summary
3. Constructor Summary
4. Method Summary
   1. Methods declared in class FilterOutputStream
   2. Methods declared in class OutputStream
   3. Methods declared in class Object
   4. Methods declared in interface DataOutput
5. Field Details
   1. written
6. Constructor Details
   1. DataOutputStream(OutputStream)
7. Method Details
   1. write(int)
   2. write(byte[], int, int)
   3. flush()
   4. writeBoolean(boolean)
   5. writeByte(int)
   6. writeShort(int)
   7. writeChar(int)
   8. writeInt(int)
   9. writeLong(long)
   10. writeFloat(float)
   11. writeDouble(double)
   12. writeBytes(String)
   13. writeChars(String)
   14. writeUTF(String)
   15. size()

• Field Summary

  Fields
  Modifier and Type

  Field

  Description

  protected int

  written

  The number of bytes written to the data output stream so far.

  Fields declared in class FilterOutputStream

  out

  Modifier and Type

  Field

  Description

  protected OutputStream

  out

  The underlying output stream to be filtered.

• Constructor Summary

  Constructors
  Constructor

  Description

  DataOutputStream(OutputStream out)

  Creates a new data output stream to write data to the specified underlying output stream.

• Method Summary

  All MethodsInstance MethodsConcrete Methods

  Modifier and Type

  Method

  Description

  void

  flush()

  Flushes this data output stream.

  final int

  size()

  Returns the current value of the counter written, the number of bytes written to this data output stream so far.

  void

  write(byte[] b, int off, int len)

  Writes len bytes from the specified byte array starting at offset off to the underlying output stream.

  void

  write(int b)

  Writes the specified byte (the low eight bits of the argument b) to the underlying output stream.

  final void

  writeBoolean(boolean v)

  Writes a boolean to the underlying output stream as a 1-byte value.

  final void

  writeByte(int v)

  Writes out a byte to the underlying output stream as a 1-byte value.

  final void

  writeBytes(String s)

  Writes out the string to the underlying output stream as a sequence of bytes.

  final void

  writeChar(int v)

  Writes a char to the underlying output stream as a 2-byte value, high byte first.

  final void

  writeChars(String s)

  Writes a string to the underlying output stream as a sequence of characters.

  final void

  writeDouble(double v)

  Converts the double argument to a long using the doubleToLongBits method in class Double, and then writes that long value to the underlying output stream as an 8-byte quantity, high byte first.

  final void

  writeFloat(float v)

  Converts the float argument to an int using the floatToIntBits method in class Float, and then writes that int value to the underlying output stream as a 4-byte quantity, high byte first.

  final void

  writeInt(int v)

  Writes an int to the underlying output stream as four bytes, high byte first.

  final void

  writeLong(long v)

  Writes a long to the underlying output stream as eight bytes, high byte first.

  final void

  writeShort(int v)

  Writes a short to the underlying output stream as two bytes, high byte first.

  final void

  writeUTF(String str)

  Writes a string to the underlying output stream using modified UTF-8 encoding in a machine-independent manner.

  Methods declared in class FilterOutputStream

  close, write

  Modifier and Type

  Method

  Description

  void

  close()

  Closes this output stream and releases any system resources associated with the stream.

  void

  write(byte[] b)

  Writes b.length bytes to this output stream.

  Methods declared in class OutputStream

  nullOutputStream

  Modifier and Type

  Method

  Description

  static OutputStream

  nullOutputStream()

  Returns a new OutputStream which discards all bytes.

  Methods declared in class Object

  clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

  Modifier and Type

  Method

  Description

  protected Object

  clone()

  Creates and returns a copy of this object.

  boolean

  equals(Object obj)

  Indicates whether some other object is "equal to" this one.

  protected void

  finalize()

  Deprecated, for removal: This API element is subject to removal in a future version.

  Finalization is deprecated and subject to removal in a future release.

  final Class<?>

  getClass()

  Returns the runtime class of this Object.

  int

  hashCode()

  Returns a hash code value for this object.

  final void

  notify()

  Wakes up a single thread that is waiting on this object's monitor.

  final void

  notifyAll()

  Wakes up all threads that are waiting on this object's monitor.

  String

  toString()

  Returns a string representation of the object.

  final void

  wait()

  Causes the current thread to wait until it is awakened, typically by being notified or interrupted.

  final void

  wait(long timeoutMillis)

  Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.

  final void

  wait(long timeoutMillis, int nanos)

  Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.

  Methods declared in interface DataOutput

  write

  Modifier and Type

  Method

  Description

  void

  write(byte[] b)

  Writes to the output stream all the bytes in array b.

• Field Details

  • written

    protected int written

    The number of bytes written to the data output stream so far. If this counter overflows, it will be wrapped to Integer.MAX_VALUE.

• Constructor Details

  • DataOutputStream

    public DataOutputStream(OutputStream out)

    Creates a new data output stream to write data to the specified underlying output stream. The counter written is set to zero.

    Parameters: out - the underlying output stream, to be saved for later use. See Also:

    • FilterOutputStream.out

• Method Details

  • write

    public void write(int b) throws IOException

    Writes the specified byte (the low eight bits of the argument b) to the underlying output stream. If no exception is thrown, the counter written is incremented by 1.

    Implements the write method of OutputStream.

    Specified by: write in interface DataOutput Overrides: write in class FilterOutputStream Parameters: b - the byte to be written. Throws: IOException - if an I/O error occurs. See Also:

    • FilterOutputStream.out

  • write

    public void write(byte[] b, int off, int len) throws IOException

    Writes len bytes from the specified byte array starting at offset off to the underlying output stream. If no exception is thrown, the counter written is incremented by len.

    Specified by: write in interface DataOutput Overrides: write in class FilterOutputStream Parameters: b - the data. off - the start offset in the data. len - the number of bytes to write. Throws: IOException - if an I/O error occurs. IndexOutOfBoundsException - If off is negative, len is negative, or len is greater than b.length - off See Also:

    • FilterOutputStream.out

  • flush

    public void flush() throws IOException

    Flushes this data output stream. This forces any buffered output bytes to be written out to the stream.

    The flush method of DataOutputStream calls the flush method of its underlying output stream.

    Specified by: flush in interface Flushable Overrides: flush in class FilterOutputStream Throws: IOException - if an I/O error occurs. See Also:

    • FilterOutputStream.out
    • OutputStream.flush()

  • writeBoolean

    public final void writeBoolean(boolean v) throws IOException

    Writes a boolean to the underlying output stream as a 1-byte value. The value true is written out as the value (byte)1; the value false is written out as the value (byte)0. If no exception is thrown, the counter written is incremented by 1.

    Specified by: writeBoolean in interface DataOutput Parameters: v - a boolean value to be written. Throws: IOException - if an I/O error occurs. See Also:

    • FilterOutputStream.out

  • writeByte

    public final void writeByte(int v) throws IOException

    Writes out a byte to the underlying output stream as a 1-byte value. If no exception is thrown, the counter written is incremented by 1.

    Specified by: writeByte in interface DataOutput Parameters: v - a byte value to be written. Throws: IOException - if an I/O error occurs. See Also:

    • FilterOutputStream.out

  • writeShort

    public final void writeShort(int v) throws IOException

    Writes a short to the underlying output stream as two bytes, high byte first. If no exception is thrown, the counter written is incremented by 2.

    Specified by: writeShort in interface DataOutput Parameters: v - a short to be written. Throws: IOException - if an I/O error occurs. See Also:

    • FilterOutputStream.out

  • writeChar

    public final void writeChar(int v) throws IOException

    Writes a char to the underlying output stream as a 2-byte value, high byte first. If no exception is thrown, the counter written is incremented by 2.

    Specified by: writeChar in interface DataOutput Parameters: v - a char value to be written. Throws: IOException - if an I/O error occurs. See Also:

    • FilterOutputStream.out

  • writeInt

    public final void writeInt(int v) throws IOException

    Writes an int to the underlying output stream as four bytes, high byte first. If no exception is thrown, the counter written is incremented by 4.

    Specified by: writeInt in interface DataOutput Parameters: v - an int to be written. Throws: IOException - if an I/O error occurs. See Also:

    • FilterOutputStream.out

  • writeLong

    public final void writeLong(long v) throws IOException

    Writes a long to the underlying output stream as eight bytes, high byte first. In no exception is thrown, the counter written is incremented by 8.

    Specified by: writeLong in interface DataOutput Parameters: v - a long to be written. Throws: IOException - if an I/O error occurs. See Also:

    • FilterOutputStream.out

  • writeFloat

    public final void writeFloat(float v) throws IOException

    Converts the float argument to an int using the floatToIntBits method in class Float, and then writes that int value to the underlying output stream as a 4-byte quantity, high byte first. If no exception is thrown, the counter written is incremented by 4.

    Specified by: writeFloat in interface DataOutput Parameters: v - a float value to be written. Throws: IOException - if an I/O error occurs. See Also:

    • FilterOutputStream.out
    • Float.floatToIntBits(float)

  • writeDouble

    public final void writeDouble(double v) throws IOException

    Converts the double argument to a long using the doubleToLongBits method in class Double, and then writes that long value to the underlying output stream as an 8-byte quantity, high byte first. If no exception is thrown, the counter written is incremented by 8.

    Specified by: writeDouble in interface DataOutput Parameters: v - a double value to be written. Throws: IOException - if an I/O error occurs. See Also:

    • FilterOutputStream.out
    • Double.doubleToLongBits(double)

  • writeBytes

    public final void writeBytes(String s) throws IOException

    Writes out the string to the underlying output stream as a sequence of bytes. Each character in the string is written out, in sequence, by discarding its high eight bits. If no exception is thrown, the counter written is incremented by the length of s.

    Specified by: writeBytes in interface DataOutput Parameters: s - a string of bytes to be written. Throws: IOException - if an I/O error occurs. See Also:

    • FilterOutputStream.out

  • writeChars

    public final void writeChars(String s) throws IOException

    Writes a string to the underlying output stream as a sequence of characters. Each character is written to the data output stream as if by the writeChar method. If no exception is thrown, the counter written is incremented by twice the length of s.

    Specified by: writeChars in interface DataOutput Parameters: s - a String value to be written. Throws: IOException - if an I/O error occurs. See Also:

    • writeChar(int)
    • FilterOutputStream.out

  • writeUTF

    public final void writeUTF(String str) throws IOException

    Writes a string to the underlying output stream using modified UTF-8 encoding in a machine-independent manner.

    First, two bytes are written to the output stream as if by the writeShort method giving the number of bytes to follow. This value is the number of bytes actually written out, not the length of the string. Following the length, each character of the string is output, in sequence, using the modified UTF-8 encoding for the character. If no exception is thrown, the counter written is incremented by the total number of bytes written to the output stream. This will be at least two plus the length of str, and at most two plus thrice the length of str.

    Specified by: writeUTF in interface DataOutput Parameters: str - a string to be written. Throws: UTFDataFormatException - if the modified UTF-8 encoding of str would exceed 65535 bytes in length IOException - if some other I/O error occurs. See Also:

    • writeChars(String)

  • size

    public final int size()

    Returns the current value of the counter written, the number of bytes written to this data output stream so far. If the counter overflows, it will be wrapped to Integer.MAX_VALUE.

    Returns: the value of the written field. See Also:

    • written

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