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Java compact1, compact2, compact3 java.io Class DataOutputStream（JDK8）

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Java™ Platform
Standard Ed. 8
compact1, compact2, compact3
java.io

Class DataOutputStream

    • Field Summary

      Fields 
      Modifier and Type Field and Description
      protected int written
      The number of bytes written to the data output stream so far.

    • Constructor Summary

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

    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method and Description
      void flush()
      Flushes this data output stream.
      int size()
      Returns the current value of the counter written, the number of bytes written to this data output stream so far.
      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.
      void writeBoolean(boolean v)
      Writes a boolean to the underlying output stream as a 1-byte value.
      void writeByte(int v)
      Writes out a byte to the underlying output stream as a 1-byte value.
      void writeBytes(String s)
      Writes out the string to the underlying output stream as a sequence of bytes.
      void writeChar(int v)
      Writes a char to the underlying output stream as a 2-byte value, high byte first.
      void writeChars(String s)
      Writes a string to the underlying output stream as a sequence of characters.
      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.
      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.
      void writeInt(int v)
      Writes an int to the underlying output stream as four bytes, high byte first.
      void writeLong(long v)
      Writes a long to the underlying output stream as eight bytes, high byte first.
      void writeShort(int v)
      Writes a short to the underlying output stream as two bytes, high byte first.
      void writeUTF(String str)
      Writes a string to the underlying output stream using modified UTF-8 encoding in a machine-independent manner.

    • Field Detail

      • written

        protected int written
        The number of bytes written to the data output stream so far. If this counter overflows, it will be wrapped to Integer.MAX_VALUE.

    • Constructor Detail

      • DataOutputStream

        public DataOutputStream(OutputStream out)
        Creates a new data output stream to write data to the specified underlying output stream. The counter written is set to zero.
        Parameters:
        out - the underlying output stream, to be saved for later use.
        See Also:
        FilterOutputStream.out

    • Method Detail

      • 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. If no exception is thrown, the counter written is incremented by 1.

        Implements the write method of OutputStream.

        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 occurs.
        See Also:
        FilterOutputStream.out

      • 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. If no exception is thrown, the counter written is incremented by len.
        Specified by:
        write in interface DataOutput
        Overrides:
        write in class FilterOutputStream
        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.
        See Also:
        FilterOutputStream.out

      • 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. If no exception is thrown, the counter written is incremented by 1.
        Specified by:
        writeBoolean in interface DataOutput
        Parameters:
        v - a boolean value to be written.
        Throws:
        IOException - if an I/O error occurs.
        See Also:
        FilterOutputStream.out

      • writeByte

        public final void writeByte(int v)
                     throws IOException
        Writes out a byte to the underlying output stream as a 1-byte value. If no exception is thrown, the counter written is incremented by 1.
        Specified by:
        writeByte in interface DataOutput
        Parameters:
        v - a byte value to be written.
        Throws:
        IOException - if an I/O error occurs.
        See Also:
        FilterOutputStream.out

      • writeShort

        public final void writeShort(int v)
                      throws IOException
        Writes a short to the underlying output stream as two bytes, high byte first. If no exception is thrown, the counter written is incremented by 2.
        Specified by:
        writeShort in interface DataOutput
        Parameters:
        v - a short to be written.
        Throws:
        IOException - if an I/O error occurs.
        See Also:
        FilterOutputStream.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. If no exception is thrown, the counter written is incremented by 2.
        Specified by:
        writeChar in interface DataOutput
        Parameters:
        v - a char value to be written.
        Throws:
        IOException - if an I/O error occurs.
        See Also:
        FilterOutputStream.out

      • writeInt

        public final void writeInt(int v)
                    throws IOException
        Writes an int to the underlying output stream as four bytes, high byte first. If no exception is thrown, the counter written is incremented by 4.
        Specified by:
        writeInt in interface DataOutput
        Parameters:
        v - an int to be written.
        Throws:
        IOException - if an I/O error occurs.
        See Also:
        FilterOutputStream.out

      • writeLong

        public final void writeLong(long v)
                     throws IOException
        Writes a long to the underlying output stream as eight bytes, high byte first. In no exception is thrown, the counter written is incremented by 8.
        Specified by:
        writeLong in interface DataOutput
        Parameters:
        v - a long to be written.
        Throws:
        IOException - if an I/O error occurs.
        See Also:
        FilterOutputStream.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. If no exception is thrown, the counter written is incremented by 4.
        Specified by:
        writeFloat in interface DataOutput
        Parameters:
        v - a float value to be written.
        Throws:
        IOException - if an I/O error occurs.
        See Also:
        FilterOutputStream.out, Float.floatToIntBits(float)

      • 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. If no exception is thrown, the counter written is incremented by 8.
        Specified by:
        writeDouble in interface DataOutput
        Parameters:
        v - a double value to be written.
        Throws:
        IOException - if an I/O error occurs.
        See Also:
        FilterOutputStream.out, Double.doubleToLongBits(double)

      • 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. If no exception is thrown, the counter written is incremented by the length of s.
        Specified by:
        writeBytes in interface DataOutput
        Parameters:
        s - a string of bytes to be written.
        Throws:
        IOException - if an I/O error occurs.
        See Also:
        FilterOutputStream.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. If no exception is thrown, the counter written is incremented by twice the length of s.
        Specified by:
        writeChars in interface DataOutput
        Parameters:
        s - a String value to be written.
        Throws:
        IOException - if an I/O error occurs.
        See Also:
        writeChar(int), FilterOutputStream.out

      • writeUTF

        public final void writeUTF(String str)
                    throws IOException
        Writes a string to the underlying output stream using modified 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 modified UTF-8 encoding for the character. If no exception is thrown, the counter written is incremented by the total number of bytes written to the output stream. This will be at least two plus the length of str, and at most two plus thrice the length of str.

        Specified by:
        writeUTF in interface DataOutput
        Parameters:
        str - a string to be written.
        Throws:
        IOException - if an I/O error occurs.

      • size

        public final int size()
        Returns the current value of the counter written, the number of bytes written to this data output stream so far. If the counter overflows, it will be wrapped to Integer.MAX_VALUE.
        Returns:
        the value of the written field.
        See Also:
        written
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Java™ Platform
Standard Ed. 8

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