java.io
Class DataOutputStream

java.lang.Object
  |
  +--java.io.OutputStream
        |
        +--java.io.FilterOutputStream
              |
              +--java.io.DataOutputStream

All Implemented Interfaces:

DataOutput

public class DataOutputStream

extends FilterOutputStream

implements DataOutput

This class lets you write primitive Java data types to a stream in a portable way. Primitive data types are well understood types with associated operations. For example, an Integer is considered to be a good primitive data type. The data can be converted back using a DataInputStream.

Field Summary

protected int

written The number of bytes written so far.

Fields inherited from class java.io.FilterOutputStream

out

Constructor Summary

DataOutputStream(OutputStream out)
Creates a new DataOutputStream.

Method Summary

void	flush() Flushes the stream.
int	size() Returns the number of bytes written.
void	write(byte[] b, int off, int len) Writes a sub array of bytes.
void	write(int b) Writes a byte.
void	writeBoolean(boolean v) Writes a boolean.
void	writeByte(int v) Writes an 8 bit byte.
void	writeBytes(String s) Writes a String as a sequence of bytes.
void	writeChar(int v) Writes a 16 bit char.
void	writeChars(String s) Writes a String as a sequence of chars.
void	writeDouble(double v) Writes a 64 bit double.
void	writeFloat(float v) Writes a 32 bit float.
void	writeInt(int v) Writes a 32 bit int.
void	writeLong(long v) Writes a 64 bit long.
void	writeShort(int v) Writes a 16 bit short.
void	writeUTF(String str) Writes a String in UTF format.

Methods inherited from class java.io.FilterOutputStream

close, write

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.io.DataOutput

write

Field Detail

written

protected int written

The number of bytes written so far.

Constructor Detail

DataOutputStream

public DataOutputStream(OutputStream out)

Creates a new DataOutputStream.

Parameters:

out - the output stream

Method Detail

write

public void write(int b)
           throws IOException

Writes a byte. Will block until the byte is actually written.

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 has occurred.

write

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

Writes a sub array of bytes.

Specified by:

write in interface DataOutput

Overrides:

write in class FilterOutputStream

Parameters:

b - the data to be written

off - the start offset in the data

len - the number of bytes that are written

Throws:

IOException - If an I/O error has occurred.

flush

public void flush()
           throws IOException

Flushes the stream. This will write any buffered output bytes.

Overrides:

flush in class FilterOutputStream

Throws:

IOException - If an I/O error has occurred.

writeBoolean

public final void writeBoolean(boolean v)
                        throws IOException

Writes a boolean.

Specified by:

writeBoolean in interface DataOutput

Parameters:

v - the boolean to be written

IOException

writeByte

public final void writeByte(int v)
                     throws IOException

Writes an 8 bit byte.

Specified by:

writeByte in interface DataOutput

Parameters:

v - the byte value to be written

IOException

writeShort

public final void writeShort(int v)
                      throws IOException

Writes a 16 bit short.

Specified by:

writeShort in interface DataOutput

Parameters:

v - the short value to be written

IOException

writeChar

public final void writeChar(int v)
                     throws IOException

Writes a 16 bit char.

Specified by:

writeChar in interface DataOutput

Parameters:

v - the char value to be written

IOException

writeInt

public final void writeInt(int v)
                    throws IOException

Writes a 32 bit int.

Specified by:

writeInt in interface DataOutput

Parameters:

v - the integer value to be written

IOException

writeLong

public final void writeLong(long v)
                     throws IOException

Writes a 64 bit long.

Specified by:

writeLong in interface DataOutput

Parameters:

v - the long value to be written

IOException

writeFloat

public final void writeFloat(float v)
                      throws IOException

Writes a 32 bit float.

Specified by:

writeFloat in interface DataOutput

Parameters:

v - the float value to be written

IOException

writeDouble

public final void writeDouble(double v)
                       throws IOException

Writes a 64 bit double.

Specified by:

writeDouble in interface DataOutput

Parameters:

v - the double value to be written

IOException

writeBytes

public final void writeBytes(String s)
                      throws IOException

Writes a String as a sequence of bytes.

Specified by:

writeBytes in interface DataOutput

Parameters:

s - the String of bytes to be written

IOException

writeChars

public final void writeChars(String s)
                      throws IOException

Writes a String as a sequence of chars.

Specified by:

writeChars in interface DataOutput

Parameters:

s - the String of chars to be written

IOException

writeUTF

public final void writeUTF(String str)
                    throws IOException

Writes a String in UTF format.

Specified by:

writeUTF in interface DataOutput

Parameters:

str - the String in UTF format

IOException

size

public final int size()

Returns the number of bytes written.

Returns:

the number of bytes written thus far.