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	/*
	* Copyright (c) 1995, 2020, Oracle and/or its affiliates. All rights reserved.
	* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
	*
	* This code is free software; you can redistribute it and/or modify it
	* under the terms of the GNU General Public License version 2 only, as
	* published by the Free Software Foundation. Oracle designates this
	* particular file as subject to the "Classpath" exception as provided
	* by Oracle in the LICENSE file that accompanied this code.
	*
	* This code is distributed in the hope that it will be useful, but WITHOUT
	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
	* version 2 for more details (a copy is included in the LICENSE file that
	* accompanied this code).
	*
	* You should have received a copy of the GNU General Public License version
	* 2 along with this work; if not, write to the Free Software Foundation,
	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
	*
	* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
	* or visit www.oracle.com if you need additional information or have any
	* questions.
	*/

	package java.io;

	/**
	* The {@code 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 {@code String} into
	* <a href="DataInput.html#modified-utf-8">modified UTF-8</a>
	* format and writing the resulting series
	* of bytes.
	* <p>
	* 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 {@code IOException} is thrown.
	*
	* @author Frank Yellin
	* @see java.io.DataInput
	* @see java.io.DataOutputStream
	* @since 1.0
	*/
	public interface DataOutput {
	/**
	* Writes to the output stream the eight
	* low-order bits of the argument {@code b}.
	* The 24 high-order bits of {@code 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 {@code b}.
	* If {@code b} is {@code null},
	* a {@code NullPointerException} is thrown.
	* If {@code b.length} is zero, then
	* no bytes are written. Otherwise, the byte
	* {@code b[0]} is written first, then
	* {@code b[1]}, and so on; the last byte
	* written is {@code b[b.length-1]}.
	*
	* @param b the data.
	* @throws IOException if an I/O error occurs.
	*/
	void write(byte b[]) throws IOException;

	/**
	* Writes {@code len} bytes from array
	* {@code b}, in order, to
	* the output stream. If {@code b}
	* is {@code null}, a {@code NullPointerException}
	* is thrown. If {@code off} is negative,
	* or {@code len} is negative, or {@code off+len}
	* is greater than the length of the array
	* {@code b}, then an {@code IndexOutOfBoundsException}
	* is thrown. If {@code len} is zero,
	* then no bytes are written. Otherwise, the
	* byte {@code b[off]} is written first,
	* then {@code b[off+1]}, and so on; the
	* last byte written is {@code 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 {@code boolean} value to this output stream.
	* If the argument {@code v}
	* is {@code true}, the value {@code (byte)1}
	* is written; if {@code v} is {@code false},
	* the value {@code (byte)0} is written.
	* The byte written by this method may
	* be read by the {@code readBoolean}
	* method of interface {@code DataInput},
	* which will then return a {@code boolean}
	* equal to {@code 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 {@code v}.
	* The 24 high-order bits of {@code v}
	* are ignored. (This means that {@code writeByte}
	* does exactly the same thing as {@code write}
	* for an integer argument.) The byte written
	* by this method may be read by the {@code readByte}
	* method of interface {@code DataInput},
	* which will then return a {@code byte}
	* equal to {@code (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:
	* <pre>{@code
	* (byte)(0xff & (v >> 8))
	* (byte)(0xff & v)
	* }</pre> <p>
	* The bytes written by this method may be
	* read by the {@code readShort} method
	* of interface {@code DataInput}, which
	* will then return a {@code short} equal
	* to {@code (short)v}.
	*
	* @param v the {@code short} value to be written.
	* @throws IOException if an I/O error occurs.
	*/
	void writeShort(int v) throws IOException;

	/**
	* Writes a {@code char} value, which
	* is comprised of two bytes, to the
	* output stream.
	* The byte values to be written, in the order
	* shown, are:
	* <pre>{@code
	* (byte)(0xff & (v >> 8))
	* (byte)(0xff & v)
	* }</pre><p>
	* The bytes written by this method may be
	* read by the {@code readChar} method
	* of interface {@code DataInput}, which
	* will then return a {@code char} equal
	* to {@code (char)v}.
	*
	* @param v the {@code char} value to be written.
	* @throws IOException if an I/O error occurs.
	*/
	void writeChar(int v) throws IOException;

	/**
	* Writes an {@code int} value, which is
	* comprised of four bytes, to the output stream.
	* The byte values to be written, in the order
	* shown, are:
	* <pre>{@code
	* (byte)(0xff & (v >> 24))
	* (byte)(0xff & (v >> 16))
	* (byte)(0xff & (v >> 8))
	* (byte)(0xff & v)
	* }</pre><p>
	* The bytes written by this method may be read
	* by the {@code readInt} method of interface
	* {@code DataInput}, which will then
	* return an {@code int} equal to {@code v}.
	*
	* @param v the {@code int} value to be written.
	* @throws IOException if an I/O error occurs.
	*/
	void writeInt(int v) throws IOException;

	/**
	* Writes a {@code long} value, which is
	* comprised of eight bytes, to the output stream.
	* The byte values to be written, in the order
	* shown, are:
	* <pre>{@code
	* (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)
	* }</pre><p>
	* The bytes written by this method may be
	* read by the {@code readLong} method
	* of interface {@code DataInput}, which
	* will then return a {@code long} equal
	* to {@code v}.
	*
	* @param v the {@code long} value to be written.
	* @throws IOException if an I/O error occurs.
	*/
	void writeLong(long v) throws IOException;

	/**
	* Writes a {@code float} value,
	* which is comprised of four bytes, to the output stream.
	* It does this as if it first converts this
	* {@code float} value to an {@code int}
	* in exactly the manner of the {@code Float.floatToIntBits}
	* method and then writes the {@code int}
	* value in exactly the manner of the {@code writeInt}
	* method. The bytes written by this method
	* may be read by the {@code readFloat}
	* method of interface {@code DataInput},
	* which will then return a {@code float}
	* equal to {@code v}.
	*
	* @param v the {@code float} value to be written.
	* @throws IOException if an I/O error occurs.
	*/
	void writeFloat(float v) throws IOException;

	/**
	* Writes a {@code double} value,
	* which is comprised of eight bytes, to the output stream.
	* It does this as if it first converts this
	* {@code double} value to a {@code long}
	* in exactly the manner of the {@code Double.doubleToLongBits}
	* method and then writes the {@code long}
	* value in exactly the manner of the {@code writeLong}
	* method. The bytes written by this method
	* may be read by the {@code readDouble}
	* method of interface {@code DataInput},
	* which will then return a {@code double}
	* equal to {@code v}.
	*
	* @param v the {@code 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
	* {@code s}, taken in order, one byte
	* is written to the output stream. If
	* {@code s} is {@code null}, a {@code NullPointerException}
	* is thrown.<p> If {@code s.length}
	* is zero, then no bytes are written. Otherwise,
	* the character {@code s[0]} is written
	* first, then {@code s[1]}, and so on;
	* the last character written is {@code s[s.length-1]}.
	* For each character, one byte is written,
	* the low-order byte, in exactly the manner
	* of the {@code 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 {@code s},
	* to the output stream, in order,
	* two bytes per character. If {@code s}
	* is {@code null}, a {@code NullPointerException}
	* is thrown. If {@code s.length}
	* is zero, then no characters are written.
	* Otherwise, the character {@code s[0]}
	* is written first, then {@code s[1]},
	* and so on; the last character written is
	* {@code s[s.length-1]}. For each character,
	* two bytes are actually written, high-order
	* byte first, in exactly the manner of the
	* {@code 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
	* <a href="DataInput.html#modified-utf-8">modified UTF-8</a>
	* representation
	* of every character in the string {@code s}.
	* If {@code s} is {@code null},
	* a {@code NullPointerException} is thrown.
	* Each character in the string {@code s}
	* is converted to a group of one, two, or
	* three bytes, depending on the value of the
	* character.<p>
	* If a character {@code c}
	* is in the range <code>\u0001</code> through
	* <code>\u007f</code>, it is represented
	* by one byte:
	* <pre>(byte)c </pre> <p>
	* If a character {@code c} is <code>\u0000</code>
	* or is in the range <code>\u0080</code>
	* through <code>\u07ff</code>, then it is
	* represented by two bytes, to be written
	* in the order shown: <pre>{@code
	* (byte)(0xc0 \| (0x1f & (c >> 6)))
	* (byte)(0x80 \| (0x3f & c))
	* }</pre> <p> If a character
	* {@code c} is in the range <code>\u0800</code>
	* through {@code uffff}, then it is
	* represented by three bytes, to be written
	* in the order shown: <pre>{@code
	* (byte)(0xe0 \| (0x0f & (c >> 12)))
	* (byte)(0x80 \| (0x3f & (c >> 6)))
	* (byte)(0x80 \| (0x3f & c))
	* }</pre> <p> First,
	* the total number of bytes needed to represent
	* all the characters of {@code s} is
	* calculated. If this number is larger than
	* {@code 65535}, then a {@code UTFDataFormatException}
	* is thrown. Otherwise, this length is written
	* to the output stream in exactly the manner
	* of the {@code writeShort} method;
	* after this, the one-, two-, or three-byte
	* representation of each character in the
	* string {@code s} is written.<p> The
	* bytes written by this method may be read
	* by the {@code readUTF} method of interface
	* {@code DataInput}, which will then
	* return a {@code String} equal to {@code s}.
	*
	* @param s the string value to be written.
	* @throws IOException if an I/O error occurs.
	*/
	void writeUTF(String s) throws IOException;
	}

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