 |
Chapter 24 The java.io Package |
 |
|
Chapter 24 The java.io Package |
|
This class is a subclass of FilterOutputStream that allows you to write Java primitive data types in a portable binary format. Create a DataOutputStream by specifying the OutputStream that is to be filtered in the call to the constructor.
Many of this class's methods write a single Java primitive type, in binary format to the output stream. write() writes a single byte, an array, or a subarray of bytes. flush() forces any buffered data to be output. size() returns the number of bytes written so far.
writeUTF() outputs a Java string of Unicode characters using a slightly modified version of the UTF-8 "transformation format." UTF-8 is an ASCII-compatible encoding of Unicode characters that is often used for the transmission and storage of Unicode text. Except for the writeUTF() method, this class is used for binary output of data. Textual output should be done with PrintWriter, or PrintStream in Java 1.0.
DataOutputStream only has methods to output primitive types. Use ObjectOutputStream to output object values.
public class DataOutputStream extends FilterOutputStream implements DataOutput {
// Public Constructor
public DataOutputStream(OutputStream out);
// Protected Instance Variables
protected int written;
// Public Instance Methods
public void flush() throws IOException; // Overrides FilterOutputStream
public final int size();
public synchronized void write(int b) throws IOException; // Overrides FilterOutputStream
public synchronized void write(byte[] b, int off, int len) throws IOException; // Overrides FilterOutputStream
public final void writeBoolean(boolean v) throws IOException; // From DataOutput
public final void writeByte(int v) throws IOException; // From DataOutput
public final void writeBytes(String s) throws IOException; // From DataOutput
public final void writeChar(int v) throws IOException; // From DataOutput
public final void writeChars(String s) throws IOException; // From DataOutput
public final void writeDouble(double v) throws IOException; // From DataOutput
public final void writeFloat(float v) throws IOException; // From DataOutput
public final void writeInt(int v) throws IOException; // From DataOutput
public final void writeLong(long v) throws IOException; // From DataOutput
public final void writeShort(int v) throws IOException; // From DataOutput
public final void writeUTF(String str) throws IOException; // From DataOutput
}
Object->OutputStream->FilterOutputStream->DataOutputStream(DataOutput)
|
 |
|
| java.io.DataOutput (JDK 1.0) |  |
java.io.EOFException (JDK 1.0) |
