Class DataOutputStream

java.lang.Object
java.io.OutputStream
java.io.DataOutputStream
All Implemented Interfaces:
DataOutput, AutoCloseable
public class DataOutputStream extends OutputStream implements DataOutput
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. Since: JDK1.0, CLDC 1.0 See Also:DataInputStream

  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    protected OutputStream
    out
    The output stream.

  • Constructor Summary

    Constructors
    Constructor
    Description
    DataOutputStream(OutputStream out)
    Creates a new data output stream to write data to the specified underlying output stream.

  • Method Summary

    Modifier and Type
    Method
    Description
    void
    close()
    Closes this output stream and releases any system resources associated with the stream.
    void
    flush()
    Flushes this data output stream.
    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
    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 UTF-8 encoding in a machine-independent manner.

    Methods inherited from class OutputStream

    write
    Modifier and Type
    Method
    Description
    void
    write(byte[] b)
    Writes b.length bytes from the specified byte array to this output stream.

    Methods inherited from class Object

    clone, equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
    Modifier and Type
    Method
    Description
    protected Object
    clone()
     
    boolean
    equals(Object obj)
    Indicates whether some other object is "equal to" this one.
    final Class
    getClass()
    Returns the runtime class of an 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()
    Causes current thread to wait until another thread invokes the method or the method for this object.
    final void
    wait(long timeout)
    Causes current thread to wait until either another thread invokes the method or the method for this object, or a specified amount of time has elapsed.
    final void
    wait(long timeout, int nanos)
    Causes current thread to wait until another thread invokes the method or the method for this object, or some other thread interrupts the current thread, or a certain amount of real time has elapsed.

    Methods inherited from interface DataOutput

    write
    Modifier and Type
    Method
    Description
    void
    write(byte[] b)
    Writes to the output stream all the bytes in array b.

  • Field Details

  • Constructor Details

    • DataOutputStream

      public DataOutputStream(OutputStream out)
      Creates a new data output stream to write data to the specified underlying output stream. out - the underlying output stream, to be saved for later use.

  • Method Details

    • close

      public void close() throws IOException
      Closes this output stream and releases any system resources associated with the stream. The close method calls its flush method, and then calls the close method of its underlying output stream.
      Specified by:
      close in interface AutoCloseable
      Overrides:
      close in class OutputStream
      Throws:
      IOException

    • 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 DataOutputStream calls the flush method of its underlying output stream.
      Overrides:
      flush in class OutputStream
      Throws:
      IOException

    • write

      public 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.
      Specified by:
      write in interface DataOutput
      Overrides:
      write in class OutputStream
      Throws:
      IOException

    • write

      public void write(int b) throws IOException
      Writes the specified byte (the low eight bits of the argument b) to the underlying output stream. Implements the write method of OutputStream.
      Specified by:
      write in interface DataOutput
      Specified by:
      write in class OutputStream
      Throws:
      IOException

    • 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.
      Specified by:
      writeBoolean in interface DataOutput
      Throws:
      IOException

    • writeByte

      public final void writeByte(int v) throws IOException
      Writes out a byte to the underlying output stream as a 1-byte value.
      Specified by:
      writeByte in interface DataOutput
      Throws:
      IOException

    • 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.
      Specified by:
      writeChar in interface DataOutput
      Throws:
      IOException

    • 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.
      Specified by:
      writeChars in interface DataOutput
      Throws:
      IOException

    • 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.
      Specified by:
      writeDouble in interface DataOutput
      Throws:
      IOException

    • 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.
      Specified by:
      writeFloat in interface DataOutput
      Throws:
      IOException

    • writeInt

      public final void writeInt(int v) throws IOException
      Writes an int to the underlying output stream as four bytes, high byte first.
      Specified by:
      writeInt in interface DataOutput
      Throws:
      IOException

    • writeLong

      public final void writeLong(long v) throws IOException
      Writes a long to the underlying output stream as eight bytes, high byte first.
      Specified by:
      writeLong in interface DataOutput
      Throws:
      IOException

    • writeShort

      public final void writeShort(int v) throws IOException
      Writes a short to the underlying output stream as two bytes, high byte first.
      Specified by:
      writeShort in interface DataOutput
      Throws:
      IOException

    • 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.
      Specified by:
      writeUTF in interface DataOutput
      Throws:
      IOException