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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * 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 1.0
 */
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:
 * <pre>{@code
 * (byte)(0xff & (v >> 8))
 * (byte)(0xff & v)
 * }</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:
 * <pre>{@code
 * (byte)(0xff & (v >> 8))
 * (byte)(0xff & v)
 * }</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:
 * <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</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:
 * <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</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>&#92;u0001</code> through
 * <code>&#92;u007f</code>, it is represented
 * by one byte:
 * <pre>(byte)c </pre> <p>
 * If a character <code>c</code> is <code>&#92;u0000</code>
 * or is in the range <code>&#92;u0080</code>
 * through <code>&#92;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</code> is in the range <code>&#92;u0800</code>
 * through <code>uffff</code>, 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</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;
}