DataOutput interface provides
- * for converting data from any of the Java
- * primitive types to a series of bytes and
- * writing these bytes to a binary stream.
- * There is also a facility for converting
- * a String into
- * modified UTF-8
- * format and writing the resulting series
- * of bytes.
- *
- * For all the methods in this interface that
- * write bytes, it is generally true that if
- * a byte cannot be written for any reason,
- * an IOException is thrown.
- *
- * @author Frank Yellin
- * @see java.io.DataInput
- * @see java.io.DataOutputStream
- * @since JDK1.0
- */
-public
-interface DataOutput {
- /**
- * Writes to the output stream the eight
- * low-order bits of the argument b.
- * The 24 high-order bits of b
- * are ignored.
- *
- * @param b the byte to be written.
- * @throws IOException if an I/O error occurs.
- */
- void write(int b) throws IOException;
-
- /**
- * Writes to the output stream all the bytes in array b.
- * If b is null,
- * a NullPointerException is thrown.
- * If b.length is zero, then
- * no bytes are written. Otherwise, the byte
- * b[0] is written first, then
- * b[1], and so on; the last byte
- * written is b[b.length-1].
- *
- * @param b the data.
- * @throws IOException if an I/O error occurs.
- */
- void write(byte b[]) throws IOException;
-
- /**
- * Writes len bytes from array
- * b, in order, to
- * the output stream. If b
- * is null, a NullPointerException
- * is thrown. If off is negative,
- * or len is negative, or off+len
- * is greater than the length of the array
- * b, then an IndexOutOfBoundsException
- * is thrown. If len is zero,
- * then no bytes are written. Otherwise, the
- * byte b[off] is written first,
- * then b[off+1], and so on; the
- * last byte written is b[off+len-1].
- *
- * @param b the data.
- * @param off the start offset in the data.
- * @param len the number of bytes to write.
- * @throws IOException if an I/O error occurs.
- */
- void write(byte b[], int off, int len) throws IOException;
-
- /**
- * Writes a boolean value to this output stream.
- * If the argument v
- * is true, the value (byte)1
- * is written; if v is false,
- * the value (byte)0 is written.
- * The byte written by this method may
- * be read by the readBoolean
- * method of interface DataInput,
- * which will then return a boolean
- * equal to v.
- *
- * @param v the boolean to be written.
- * @throws IOException if an I/O error occurs.
- */
- void writeBoolean(boolean v) throws IOException;
-
- /**
- * Writes to the output stream the eight low-
- * order bits of the argument v.
- * The 24 high-order bits of v
- * are ignored. (This means that writeByte
- * does exactly the same thing as write
- * for an integer argument.) The byte written
- * by this method may be read by the readByte
- * method of interface DataInput,
- * which will then return a byte
- * equal to (byte)v.
- *
- * @param v the byte value to be written.
- * @throws IOException if an I/O error occurs.
- */
- void writeByte(int v) throws IOException;
-
- /**
- * Writes two bytes to the output
- * stream to represent the value of the argument.
- * The byte values to be written, in the order
- * shown, are:
- *
- * (byte)(0xff & (v >> 8))
- * (byte)(0xff & v)
- *
- * The bytes written by this method may be
- * read by the readShort method
- * of interface DataInput , which
- * will then return a short equal
- * to (short)v.
- *
- * @param v the short value to be written.
- * @throws IOException if an I/O error occurs.
- */
- void writeShort(int v) throws IOException;
-
- /**
- * Writes a char value, which
- * is comprised of two bytes, to the
- * output stream.
- * The byte values to be written, in the order
- * shown, are:
- *
- * (byte)(0xff & (v >> 8))
- * (byte)(0xff & v)
- *
- * The bytes written by this method may be
- * read by the readChar method
- * of interface DataInput , which
- * will then return a char equal
- * to (char)v.
- *
- * @param v the char value to be written.
- * @throws IOException if an I/O error occurs.
- */
- void writeChar(int v) throws IOException;
-
- /**
- * Writes an int value, which is
- * comprised of four bytes, to the output stream.
- * The byte values to be written, in the order
- * shown, are:
- *
- * (byte)(0xff & (v >> 24))
- * (byte)(0xff & (v >> 16))
- * (byte)(0xff & (v >> 8))
- * (byte)(0xff & v)
- *
- * The bytes written by this method may be read
- * by the readInt method of interface
- * DataInput , which will then
- * return an int equal to v.
- *
- * @param v the int value to be written.
- * @throws IOException if an I/O error occurs.
- */
- void writeInt(int v) throws IOException;
-
- /**
- * Writes a long value, which is
- * comprised of eight bytes, to the output stream.
- * The byte values to be written, in the order
- * shown, are:
- *
- * (byte)(0xff & (v >> 56))
- * (byte)(0xff & (v >> 48))
- * (byte)(0xff & (v >> 40))
- * (byte)(0xff & (v >> 32))
- * (byte)(0xff & (v >> 24))
- * (byte)(0xff & (v >> 16))
- * (byte)(0xff & (v >> 8))
- * (byte)(0xff & v)
- *
- * The bytes written by this method may be
- * read by the readLong method
- * of interface DataInput , which
- * will then return a long equal
- * to v.
- *
- * @param v the long value to be written.
- * @throws IOException if an I/O error occurs.
- */
- void writeLong(long v) throws IOException;
-
- /**
- * Writes a float value,
- * which is comprised of four bytes, to the output stream.
- * It does this as if it first converts this
- * float value to an int
- * in exactly the manner of the Float.floatToIntBits
- * method and then writes the int
- * value in exactly the manner of the writeInt
- * method. The bytes written by this method
- * may be read by the readFloat
- * method of interface DataInput,
- * which will then return a float
- * equal to v.
- *
- * @param v the float value to be written.
- * @throws IOException if an I/O error occurs.
- */
- void writeFloat(float v) throws IOException;
-
- /**
- * Writes a double value,
- * which is comprised of eight bytes, to the output stream.
- * It does this as if it first converts this
- * double value to a long
- * in exactly the manner of the Double.doubleToLongBits
- * method and then writes the long
- * value in exactly the manner of the writeLong
- * method. The bytes written by this method
- * may be read by the readDouble
- * method of interface DataInput,
- * which will then return a double
- * equal to v.
- *
- * @param v the double value to be written.
- * @throws IOException if an I/O error occurs.
- */
- void writeDouble(double v) throws IOException;
-
- /**
- * Writes a string to the output stream.
- * For every character in the string
- * s, taken in order, one byte
- * is written to the output stream. If
- * s is null, a NullPointerException
- * is thrown.
If s.length
- * is zero, then no bytes are written. Otherwise,
- * the character s[0] is written
- * first, then s[1], and so on;
- * the last character written is s[s.length-1].
- * For each character, one byte is written,
- * the low-order byte, in exactly the manner
- * of the writeByte method . The
- * high-order eight bits of each character
- * in the string are ignored.
- *
- * @param s the string of bytes to be written.
- * @throws IOException if an I/O error occurs.
- */
- void writeBytes(String s) throws IOException;
-
- /**
- * Writes every character in the string s,
- * to the output stream, in order,
- * two bytes per character. If s
- * is null, a NullPointerException
- * is thrown. If s.length
- * is zero, then no characters are written.
- * Otherwise, the character s[0]
- * is written first, then s[1],
- * and so on; the last character written is
- * s[s.length-1]. For each character,
- * two bytes are actually written, high-order
- * byte first, in exactly the manner of the
- * writeChar method.
- *
- * @param s the string value to be written.
- * @throws IOException if an I/O error occurs.
- */
- void writeChars(String s) throws IOException;
-
- /**
- * Writes two bytes of length information
- * to the output stream, followed
- * by the
- * modified UTF-8
- * representation
- * of every character in the string s.
- * If s is null,
- * a NullPointerException is thrown.
- * Each character in the string s
- * is converted to a group of one, two, or
- * three bytes, depending on the value of the
- * character.
- * If a character c
- * is in the range \u0001 through
- * \u007f, it is represented
- * by one byte:
- *
(byte)c
- * If a character c is \u0000
- * or is in the range \u0080
- * through \u07ff, then it is
- * represented by two bytes, to be written
- * in the order shown:
- * (byte)(0xc0 | (0x1f & (c >> 6)))
- * (byte)(0x80 | (0x3f & c))
- * If a character
- * c is in the range \u0800
- * through uffff, then it is
- * represented by three bytes, to be written
- * in the order shown:
- * (byte)(0xe0 | (0x0f & (c >> 12)))
- * (byte)(0x80 | (0x3f & (c >> 6)))
- * (byte)(0x80 | (0x3f & c))
- * First,
- * the total number of bytes needed to represent
- * all the characters of s is
- * calculated. If this number is larger than
- * 65535, then a UTFDataFormatException
- * is thrown. Otherwise, this length is written
- * to the output stream in exactly the manner
- * of the writeShort method;
- * after this, the one-, two-, or three-byte
- * representation of each character in the
- * string s is written.
The
- * bytes written by this method may be read
- * by the readUTF method of interface
- * DataInput , which will then
- * return a String equal to s.
- *
- * @param s the string value to be written.
- * @throws IOException if an I/O error occurs.
- */
- void writeUTF(String s) throws IOException;
-}