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* 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
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package java.io;
/**
* The <code>DataOutput</code> 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</code> 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</code> 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 <code>b</code>.
* The 24 high-order bits of <code>b</code>
* 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</code>.
* If <code>b</code> is <code>null</code>,
* a <code>NullPointerException</code> is thrown.
* If <code>b.length</code> is zero, then
* no bytes are written. Otherwise, the byte
* <code>b[0]</code> is written first, then
* <code>b[1]</code>, and so on; the last byte
* written is <code>b[b.length-1]</code>.
*
* @param b the data.
* @throws IOException if an I/O error occurs.
*/
void write(byte b[]) throws IOException;
/**
* Writes <code>len</code> bytes from array
* <code>b</code>, in order, to
* the output stream. If <code>b</code>
* is <code>null</code>, a <code>NullPointerException</code>
* is thrown. If <code>off</code> is negative,
* or <code>len</code> is negative, or <code>off+len</code>
* is greater than the length of the array
* <code>b</code>, then an <code>IndexOutOfBoundsException</code>
* is thrown. If <code>len</code> is zero,
* then no bytes are written. Otherwise, the
* byte <code>b[off]</code> is written first,
* then <code>b[off+1]</code>, and so on; the
* last byte written is <code>b[off+len-1]</code>.
*
* @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</code> value to this output stream.
* If the argument <code>v</code>
* is <code>true</code>, the value <code>(byte)1</code>
* is written; if <code>v</code> is <code>false</code>,
* the value <code>(byte)0</code> is written.
* The byte written by this method may
* be read by the <code>readBoolean</code>
* method of interface <code>DataInput</code>,
* which will then return a <code>boolean</code>
* equal to <code>v</code>.
*
* @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</code>.
* The 24 high-order bits of <code>v</code>
* are ignored. (This means that <code>writeByte</code>
* does exactly the same thing as <code>write</code>
* for an integer argument.) The byte written
* by this method may be read by the <code>readByte</code>
* method of interface <code>DataInput</code>,
* which will then return a <code>byte</code>
* equal to <code>(byte)v</code>.
*
* @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: <p>
* <pre><code>
* (byte)(0xff & (v >> 8))
* (byte)(0xff & v)
* </code> </pre> <p>
* The bytes written by this method may be
* read by the <code>readShort</code> method
* of interface <code>DataInput</code> , which
* will then return a <code>short</code> equal
* to <code>(short)v</code>.
*
* @param v the <code>short</code> value to be written.
* @throws IOException if an I/O error occurs.
*/
void writeShort(int v) throws IOException;
/**
* Writes a <code>char</code> value, which
* is comprised of two bytes, to the
* output stream.
* The byte values to be written, in the order
* shown, are:
* <p><pre><code>
* (byte)(0xff & (v >> 8))
* (byte)(0xff & v)
* </code></pre><p>
* The bytes written by this method may be
* read by the <code>readChar</code> method
* of interface <code>DataInput</code> , which
* will then return a <code>char</code> equal
* to <code>(char)v</code>.
*
* @param v the <code>char</code> value to be written.
* @throws IOException if an I/O error occurs.
*/
void writeChar(int v) throws IOException;
/**
* Writes an <code>int</code> value, which is
* comprised of four bytes, to the output stream.
* The byte values to be written, in the order
* shown, are:
* <p><pre><code>
* (byte)(0xff & (v >> 24))
* (byte)(0xff & (v >> 16))
* (byte)(0xff & (v >> 8))
* (byte)(0xff & v)
* </code></pre><p>
* The bytes written by this method may be read
* by the <code>readInt</code> method of interface
* <code>DataInput</code> , which will then
* return an <code>int</code> equal to <code>v</code>.
*
* @param v the <code>int</code> value to be written.
* @throws IOException if an I/O error occurs.
*/
void writeInt(int v) throws IOException;
/**
* Writes a <code>long</code> value, which is
* comprised of eight bytes, to the output stream.
* The byte values to be written, in the order
* shown, are:
* <p><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)
* </code></pre><p>
* The bytes written by this method may be
* read by the <code>readLong</code> method
* of interface <code>DataInput</code> , which
* will then return a <code>long</code> equal
* to <code>v</code>.
*
* @param v the <code>long</code> value to be written.
* @throws IOException if an I/O error occurs.
*/
void writeLong(long v) throws IOException;
/**
* Writes a <code>float</code> value,
* which is comprised of four bytes, to the output stream.
* It does this as if it first converts this
* <code>float</code> value to an <code>int</code>
* in exactly the manner of the <code>Float.floatToIntBits</code>
* method and then writes the <code>int</code>
* value in exactly the manner of the <code>writeInt</code>
* method. The bytes written by this method
* may be read by the <code>readFloat</code>
* method of interface <code>DataInput</code>,
* which will then return a <code>float</code>
* equal to <code>v</code>.
*
* @param v the <code>float</code> value to be written.
* @throws IOException if an I/O error occurs.
*/
void writeFloat(float v) throws IOException;
/**
* Writes a <code>double</code> value,
* which is comprised of eight bytes, to the output stream.
* It does this as if it first converts this
* <code>double</code> value to a <code>long</code>
* in exactly the manner of the <code>Double.doubleToLongBits</code>
* method and then writes the <code>long</code>
* value in exactly the manner of the <code>writeLong</code>
* method. The bytes written by this method
* may be read by the <code>readDouble</code>
* method of interface <code>DataInput</code>,
* which will then return a <code>double</code>
* equal to <code>v</code>.
*
* @param v the <code>double</code> 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</code>, taken in order, one byte
* is written to the output stream. If
* <code>s</code> is <code>null</code>, a <code>NullPointerException</code>
* is thrown.<p> If <code>s.length</code>
* is zero, then no bytes are written. Otherwise,
* the character <code>s[0]</code> is written
* first, then <code>s[1]</code>, and so on;
* the last character written is <code>s[s.length-1]</code>.
* For each character, one byte is written,
* the low-order byte, in exactly the manner
* of the <code>writeByte</code> 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</code>,
* to the output stream, in order,
* two bytes per character. If <code>s</code>
* is <code>null</code>, a <code>NullPointerException</code>
* is thrown. If <code>s.length</code>
* is zero, then no characters are written.
* Otherwise, the character <code>s[0]</code>
* is written first, then <code>s[1]</code>,
* and so on; the last character written is
* <code>s[s.length-1]</code>. For each character,
* two bytes are actually written, high-order
* byte first, in exactly the manner of the
* <code>writeChar</code> 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</code>.
* If <code>s</code> is <code>null</code>,
* a <code>NullPointerException</code> is thrown.
* Each character in the string <code>s</code>
* is converted to a group of one, two, or
* three bytes, depending on the value of the
* character.<p>
* If a character <code>c</code>
* is in the range <code>\u0001</code> through
* <code>\u007f</code>, it is represented
* by one byte:<p>
* <pre>(byte)c </pre> <p>
* If a character <code>c</code> 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:<p> <pre><code>
* (byte)(0xc0 | (0x1f & (c >> 6)))
* (byte)(0x80 | (0x3f & c))
* </code></pre> <p> If a character
* <code>c</code> is in the range <code>\u0800</code>
* through <code>uffff</code>, then it is
* represented by three bytes, to be written
* in the order shown:<p> <pre><code>
* (byte)(0xe0 | (0x0f & (c >> 12)))
* (byte)(0x80 | (0x3f & (c >> 6)))
* (byte)(0x80 | (0x3f & c))
* </code></pre> <p> First,
* the total number of bytes needed to represent
* all the characters of <code>s</code> is
* calculated. If this number is larger than
* <code>65535</code>, then a <code>UTFDataFormatException</code>
* is thrown. Otherwise, this length is written
* to the output stream in exactly the manner
* of the <code>writeShort</code> method;
* after this, the one-, two-, or three-byte
* representation of each character in the
* string <code>s</code> is written.<p> The
* bytes written by this method may be read
* by the <code>readUTF</code> method of interface
* <code>DataInput</code> , which will then
* return a <code>String</code> equal to <code>s</code>.
*
* @param s the string value to be written.
* @throws IOException if an I/O error occurs.
*/
void writeUTF(String s) throws IOException;
}