站内搜索: 请输入搜索关键词
当前页面: 在线文档首页 > JDK 5 Documentation v1.1.8, Java 2 SDK 英文文档

Class java.io.DataOutputStream - JDK 5 Documentation v1.1.8, Java 2 SDK 英文文档

All Packages  Class Hierarchy  This Package  Previous  Next  Index

Class java.io.DataOutputStream

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

public class DataOutputStream
extends FilterOutputStream
implements DataOutput
A data input 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

Variable Index

 o written
The number of bytes written to the data output stream.

Constructor Index

 o DataOutputStream(OutputStream)
Creates a new data output stream to write data to the specified underlying output stream.

Method Index

 o flush()
Flushes this data output stream.
 o size()
Returns the number of bytes written to this data output stream.
 o write(byte[], int, int)
Writes len bytes from the specified byte array starting at offset off to the underlying output stream.
 o write(int)
Writes the specified byte to the underlying output stream.
 o writeBoolean(boolean)
Writes a boolean to the underlying output stream as a 1-byte value.
 o writeByte(int)
Writes out a byte to the underlying output stream as a 1-byte value.
 o writeBytes(String)
Writes out the string to the underlying output stream as a sequence of bytes.
 o writeChar(int)
Writes a char to the underlying output stream as a 2-byte value, high byte first.
 o writeChars(String)
Writes a string to the underlying output stream as a sequence of characters.
 o writeDouble(double)
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.
 o writeFloat(float)
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.
 o writeInt(int)
Writes an int to the underlying output stream as four bytes, high byte first.
 o writeLong(long)
Writes a long to the underlying output stream as eight bytes, high byte first.
 o writeShort(int)
Writes a short to the underlying output stream as two bytes, high byte first.
 o writeUTF(String)
Writes a string to the underlying output stream using UTF-8 encoding in a machine-independent manner.

Variables

 o written
 protected int written
The number of bytes written to the data output stream.

Constructors

 o DataOutputStream
 public DataOutputStream(OutputStream out)
Creates a new data output stream to write data to the specified underlying output stream.

Parameters:
out - the underlying output stream.
See Also:
out

Methods

 o write
 public synchronized void write(int b) throws IOException
Writes the specified byte to the underlying output stream.

Parameters:
b - the byte to be written.
Throws: IOException
if an I/O error occurs.
Overrides:
write in class FilterOutputStream
See Also:
out
 o write
 public synchronized 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.

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.
Overrides:
write in class FilterOutputStream
See Also:
out
 o 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 DataOuputStream calls the flush method of its underlying output stream.

Throws: IOException
if an I/O error occurs.
Overrides:
flush in class FilterOutputStream
See Also:
out, flush
 o 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.

Parameters:
v - a boolean value to be written.
Throws: IOException
if an I/O error occurs.
See Also:
out
 o writeByte
 public final void writeByte(int v) throws IOException
Writes out a byte to the underlying output stream as a 1-byte value.

Parameters:
v - a byte value to be written.
Throws: IOException
if an I/O error occurs.
See Also:
out
 o writeShort
 public final void writeShort(int v) throws IOException
Writes a short to the underlying output stream as two bytes, high byte first.

Parameters:
v - a short to be written.
Throws: IOException
if an I/O error occurs.
See Also:
out
 o 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.

Parameters:
v - a char value to be written.
Throws: IOException
if an I/O error occurs.
See Also:
out
 o writeInt
 public final void writeInt(int v) throws IOException
Writes an int to the underlying output stream as four bytes, high byte first.

Parameters:
v - an int to be written.
Throws: IOException
if an I/O error occurs.
See Also:
out
 o writeLong
 public final void writeLong(long v) throws IOException
Writes a long to the underlying output stream as eight bytes, high byte first.

Parameters:
v - a long to be written.
Throws: IOException
if an I/O error occurs.
See Also:
out
 o 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.

Parameters:
v - a float value to be written.
Throws: IOException
if an I/O error occurs.
See Also:
out, floatToIntBits
 o 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.

Parameters:
v - a double value to be written.
Throws: IOException
if an I/O error occurs.
See Also:
out, doubleToLongBits
 o 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.

Parameters:
s - a string of bytes to be written.
Throws: IOException
if an I/O error occurs.
See Also:
out
 o 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.

Parameters:
s - a String value to be written.
Throws: IOException
if an I/O error occurs.
See Also:
writeChar, out
 o writeUTF
 public final void writeUTF(String str) throws IOException
Writes a string to the underlying output stream using 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 UTF-8 encoding for the character.

Parameters:
str - a string to be written.
Throws: IOException
if an I/O error occurs.
 o size
 public final int size()
Returns the number of bytes written to this data output stream.

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

All Packages  Class Hierarchy  This Package  Previous  Next  Index

Submit a bug or feature - Version 1.1.8 of Java Platform API Specification
Java is a trademark or registered trademark of Sun Microsystems, Inc. in the US and other countries.
Copyright 1995-1999 Sun Microsystems, Inc. 901 San Antonio Road,
Palo Alto, California, 94303, U.S.A. All Rights Reserved.