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

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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

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

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

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

written

 protected int written

The number of bytes written to the data output stream.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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.

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

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