Added in API level 1

Summary: Fields | Inherited Fields | Ctors | Methods | Inherited Methods

DataOutputStream

public class DataOutputStream
extends FilterOutputStream implements DataOutput

java.lang.Object
↳	java.io.OutputStream
	↳	java.io.FilterOutputStream
		↳	java.io.DataOutputStream

A data output stream lets an application write primitive Java data types to an output stream in a portable way. An application can then use a data input stream to read the data back in.

See also:

DataInputStream

Summary

Fields
`protected int`	`written` The number of bytes written to the data output stream so far.

Inherited fields

From class java.io.FilterOutputStream


    protected
    
    
    OutputStream

out

The underlying output stream to be filtered.

Public constructors
`DataOutputStream(OutputStream out)` Creates a new data output stream to write data to the specified underlying output stream.

Public methods
`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.

Inherited methods

From class


        
          java.io.FilterOutputStream

`void`	`close()` Closes this output stream and releases any system resources associated with the stream.
`void`	`flush()` Flushes this output stream and forces any buffered output bytes to be written out to the stream.
`void`	`write(byte[] b)` Writes `b.length` bytes to this output stream.
`void`	`write(byte[] b, int off, int len)` Writes `len` bytes from the specified `byte` array starting at offset `off` to this output stream.
`void`	`write(int b)` Writes the specified `byte` to this output stream.

From class


        
          java.io.OutputStream

`void`	`close()` Closes this output stream and releases any system resources associated with this stream.
`void`	`flush()` Flushes this output stream and forces any buffered output bytes to be written out.
`static OutputStream`	`nullOutputStream()` Returns a new `OutputStream` which discards all bytes.
`void`	`write(byte[] b)` Writes `b.length` bytes from the specified byte array to this output stream.
`void`	`write(byte[] b, int off, int len)` Writes `len` bytes from the specified byte array starting at offset `off` to this output stream.
`abstract void`	`write(int b)` Writes the specified byte to this output stream.

From class


        
          java.lang.Object

`Object`	`clone()` Creates and returns a copy of this object.
`boolean`	`equals(Object obj)` Indicates whether some other object is "equal to" this one.
`void`	`finalize()` Called by the garbage collector on an object when garbage collection determines that there are no more references to the object.
`final Class<?>`	`getClass()` Returns the runtime class of this `Object`.
`int`	`hashCode()` Returns a hash code value for the 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(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.
`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()` Causes the current thread to wait until it is awakened, typically by being notified or interrupted.

From interface


        
          java.io.Closeable


      close()

Closes this stream and releases any system resources associated with it.

From interface


        
          java.io.Flushable


      flush()

Flushes this stream by writing any buffered output to the underlying stream.

From interface


        
          java.io.DataOutput

`abstract void`	`write(byte[] b)` Writes to the output stream all the bytes in array `b`.
`abstract void`	`write(byte[] b, int off, int len)` Writes `len` bytes from array `b`, in order, to the output stream.
`abstract void`	`write(int b)` Writes to the output stream the eight low-order bits of the argument `b`.
`abstract void`	`writeBoolean(boolean v)` Writes a `boolean` value to this output stream.
`abstract void`	`writeByte(int v)` Writes to the output stream the eight low- order bits of the argument `v`.
`abstract void`	`writeBytes(String s)` Writes a string to the output stream.
`abstract void`	`writeChar(int v)` Writes a `char` value, which is comprised of two bytes, to the output stream.
`abstract void`	`writeChars(String s)` Writes every character in the string `s`, to the output stream, in order, two bytes per character.
`abstract void`	`writeDouble(double v)` Writes a `double` value, which is comprised of eight bytes, to the output stream.
`abstract void`	`writeFloat(float v)` Writes a `float` value, which is comprised of four bytes, to the output stream.
`abstract void`	`writeInt(int v)` Writes an `int` value, which is comprised of four bytes, to the output stream.
`abstract void`	`writeLong(long v)` Writes a `long` value, which is comprised of eight bytes, to the output stream.
`abstract void`	`writeShort(int v)` Writes two bytes to the output stream to represent the value of the argument.
`abstract void`	`writeUTF(String s)` Writes two bytes of length information to the output stream, followed by the modified UTF-8 representation of every character in the string `s`.

From interface


        
          java.lang.AutoCloseable


      close()

Closes this resource, relinquishing any underlying resources.

Fields

written

Added in API level 1

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.

Public constructors

DataOutputStream

Added in API level 1

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`	`OutputStream`: the underlying output stream, to be saved for later use.

See also:

FilterOutputStream.out

Public methods

flush

Added in API level 1

public void flush ()

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.

Throws
`IOException`	if an I/O error occurs.

See also:

size

Added in API level 1

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
`int`	the value of the `written` field.

See also:

written

write

Added in API level 1

public 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. If no exception is thrown, the counter written is incremented by len.

Parameters
`b`	`byte`: the data.
`off`	`int`: the start offset in the data.
`len`	`int`: the number of bytes to write.

Throws
`IOException`	if an I/O error occurs.

See also:

FilterOutputStream.out

write

Added in API level 1

public void write (int b)

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.

Parameters
`b`	`int`: the `byte` to be written.

Throws
`IOException`	if an I/O error occurs.

See also:

FilterOutputStream.out

writeBoolean

Added in API level 1

public final void writeBoolean (boolean v)

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.

Parameters
`v`	`boolean`: a `boolean` value to be written.

Throws
`IOException`	if an I/O error occurs.

See also:

FilterOutputStream.out

writeByte

Added in API level 1

public final void writeByte (int v)

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.

Parameters
`v`	`int`: a `byte` value to be written.

Throws
`IOException`	if an I/O error occurs.

See also:

FilterOutputStream.out

writeBytes

Added in API level 1

public final void writeBytes (String s)

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.

Parameters
`s`	`String`: a string of bytes to be written.

Throws
`IOException`	if an I/O error occurs.

See also:

FilterOutputStream.out

writeChar

Added in API level 1

public final void writeChar (int v)

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.

Parameters
`v`	`int`: a `char` value to be written.

Throws
`IOException`	if an I/O error occurs.

See also:

FilterOutputStream.out

writeChars

Added in API level 1

public final void writeChars (String s)

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.

Parameters
`s`	`String`: a `String` value to be written.

Throws
`IOException`	if an I/O error occurs.

See also:

writeDouble

Added in API level 1

public 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. If no exception is thrown, the counter written is incremented by 8.

Parameters
`v`	`double`: a `double` value to be written.

Throws
`IOException`	if an I/O error occurs.

See also:

writeFloat

Added in API level 1

public 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. If no exception is thrown, the counter written is incremented by 4.

Parameters
`v`	`float`: a `float` value to be written.

Throws
`IOException`	if an I/O error occurs.

See also:

writeInt

Added in API level 1

public final void writeInt (int v)

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.

Parameters
`v`	`int`: an `int` to be written.

Throws
`IOException`	if an I/O error occurs.

See also:

FilterOutputStream.out

writeLong

Added in API level 1

public final void writeLong (long v)

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.

Parameters
`v`	`long`: a `long` to be written.

Throws
`IOException`	if an I/O error occurs.

See also:

FilterOutputStream.out

writeShort

Added in API level 1

public final void writeShort (int v)

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.

Parameters
`v`	`int`: a `short` to be written.

Throws
`IOException`	if an I/O error occurs.

See also:

FilterOutputStream.out

writeUTF

Added in API level 1

public final void writeUTF (String str)

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.

Parameters
`str`	`String`: a string to be written.

Throws
`IOException`	if an I/O error occurs.