jaroslav@601: /*
jaroslav@601:  * Copyright (c) 1995, 2006, Oracle and/or its affiliates. All rights reserved.
jaroslav@601:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
jaroslav@601:  *
jaroslav@601:  * This code is free software; you can redistribute it and/or modify it
jaroslav@601:  * under the terms of the GNU General Public License version 2 only, as
jaroslav@601:  * published by the Free Software Foundation.  Oracle designates this
jaroslav@601:  * particular file as subject to the "Classpath" exception as provided
jaroslav@601:  * by Oracle in the LICENSE file that accompanied this code.
jaroslav@601:  *
jaroslav@601:  * This code is distributed in the hope that it will be useful, but WITHOUT
jaroslav@601:  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
jaroslav@601:  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
jaroslav@601:  * version 2 for more details (a copy is included in the LICENSE file that
jaroslav@601:  * accompanied this code).
jaroslav@601:  *
jaroslav@601:  * You should have received a copy of the GNU General Public License version
jaroslav@601:  * 2 along with this work; if not, write to the Free Software Foundation,
jaroslav@601:  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
jaroslav@601:  *
jaroslav@601:  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
jaroslav@601:  * or visit www.oracle.com if you need additional information or have any
jaroslav@601:  * questions.
jaroslav@601:  */
jaroslav@601: 
jaroslav@601: package java.io;
jaroslav@601: 
jaroslav@601: /**
jaroslav@601:  * The <code>DataOutput</code> interface provides
jaroslav@601:  * for converting data from any of the Java
jaroslav@601:  * primitive types to a series of bytes and
jaroslav@601:  * writing these bytes to a binary stream.
jaroslav@601:  * There is  also a facility for converting
jaroslav@601:  * a <code>String</code> into
jaroslav@601:  * <a href="DataInput.html#modified-utf-8">modified UTF-8</a>
jaroslav@601:  * format and writing the resulting series
jaroslav@601:  * of bytes.
jaroslav@601:  * <p>
jaroslav@601:  * For all the methods in this interface that
jaroslav@601:  * write bytes, it is generally true that if
jaroslav@601:  * a byte cannot be written for any reason,
jaroslav@601:  * an <code>IOException</code> is thrown.
jaroslav@601:  *
jaroslav@601:  * @author  Frank Yellin
jaroslav@601:  * @see     java.io.DataInput
jaroslav@601:  * @see     java.io.DataOutputStream
jaroslav@601:  * @since   JDK1.0
jaroslav@601:  */
jaroslav@601: public
jaroslav@601: interface DataOutput {
jaroslav@601:     /**
jaroslav@601:      * Writes to the output stream the eight
jaroslav@601:      * low-order bits of the argument <code>b</code>.
jaroslav@601:      * The 24 high-order  bits of <code>b</code>
jaroslav@601:      * are ignored.
jaroslav@601:      *
jaroslav@601:      * @param      b   the byte to be written.
jaroslav@601:      * @throws     IOException  if an I/O error occurs.
jaroslav@601:      */
jaroslav@601:     void write(int b) throws IOException;
jaroslav@601: 
jaroslav@601:     /**
jaroslav@601:      * Writes to the output stream all the bytes in array <code>b</code>.
jaroslav@601:      * If <code>b</code> is <code>null</code>,
jaroslav@601:      * a <code>NullPointerException</code> is thrown.
jaroslav@601:      * If <code>b.length</code> is zero, then
jaroslav@601:      * no bytes are written. Otherwise, the byte
jaroslav@601:      * <code>b[0]</code> is written first, then
jaroslav@601:      * <code>b[1]</code>, and so on; the last byte
jaroslav@601:      * written is <code>b[b.length-1]</code>.
jaroslav@601:      *
jaroslav@601:      * @param      b   the data.
jaroslav@601:      * @throws     IOException  if an I/O error occurs.
jaroslav@601:      */
jaroslav@601:     void write(byte b[]) throws IOException;
jaroslav@601: 
jaroslav@601:     /**
jaroslav@601:      * Writes <code>len</code> bytes from array
jaroslav@601:      * <code>b</code>, in order,  to
jaroslav@601:      * the output stream.  If <code>b</code>
jaroslav@601:      * is <code>null</code>, a <code>NullPointerException</code>
jaroslav@601:      * is thrown.  If <code>off</code> is negative,
jaroslav@601:      * or <code>len</code> is negative, or <code>off+len</code>
jaroslav@601:      * is greater than the length of the array
jaroslav@601:      * <code>b</code>, then an <code>IndexOutOfBoundsException</code>
jaroslav@601:      * is thrown.  If <code>len</code> is zero,
jaroslav@601:      * then no bytes are written. Otherwise, the
jaroslav@601:      * byte <code>b[off]</code> is written first,
jaroslav@601:      * then <code>b[off+1]</code>, and so on; the
jaroslav@601:      * last byte written is <code>b[off+len-1]</code>.
jaroslav@601:      *
jaroslav@601:      * @param      b     the data.
jaroslav@601:      * @param      off   the start offset in the data.
jaroslav@601:      * @param      len   the number of bytes to write.
jaroslav@601:      * @throws     IOException  if an I/O error occurs.
jaroslav@601:      */
jaroslav@601:     void write(byte b[], int off, int len) throws IOException;
jaroslav@601: 
jaroslav@601:     /**
jaroslav@601:      * Writes a <code>boolean</code> value to this output stream.
jaroslav@601:      * If the argument <code>v</code>
jaroslav@601:      * is <code>true</code>, the value <code>(byte)1</code>
jaroslav@601:      * is written; if <code>v</code> is <code>false</code>,
jaroslav@601:      * the  value <code>(byte)0</code> is written.
jaroslav@601:      * The byte written by this method may
jaroslav@601:      * be read by the <code>readBoolean</code>
jaroslav@601:      * method of interface <code>DataInput</code>,
jaroslav@601:      * which will then return a <code>boolean</code>
jaroslav@601:      * equal to <code>v</code>.
jaroslav@601:      *
jaroslav@601:      * @param      v   the boolean to be written.
jaroslav@601:      * @throws     IOException  if an I/O error occurs.
jaroslav@601:      */
jaroslav@601:     void writeBoolean(boolean v) throws IOException;
jaroslav@601: 
jaroslav@601:     /**
jaroslav@601:      * Writes to the output stream the eight low-
jaroslav@601:      * order bits of the argument <code>v</code>.
jaroslav@601:      * The 24 high-order bits of <code>v</code>
jaroslav@601:      * are ignored. (This means  that <code>writeByte</code>
jaroslav@601:      * does exactly the same thing as <code>write</code>
jaroslav@601:      * for an integer argument.) The byte written
jaroslav@601:      * by this method may be read by the <code>readByte</code>
jaroslav@601:      * method of interface <code>DataInput</code>,
jaroslav@601:      * which will then return a <code>byte</code>
jaroslav@601:      * equal to <code>(byte)v</code>.
jaroslav@601:      *
jaroslav@601:      * @param      v   the byte value to be written.
jaroslav@601:      * @throws     IOException  if an I/O error occurs.
jaroslav@601:      */
jaroslav@601:     void writeByte(int v) throws IOException;
jaroslav@601: 
jaroslav@601:     /**
jaroslav@601:      * Writes two bytes to the output
jaroslav@601:      * stream to represent the value of the argument.
jaroslav@601:      * The byte values to be written, in the  order
jaroslav@601:      * shown, are: <p>
jaroslav@601:      * <pre><code>
jaroslav@601:      * (byte)(0xff &amp; (v &gt;&gt; 8))
jaroslav@601:      * (byte)(0xff &amp; v)
jaroslav@601:      * </code> </pre> <p>
jaroslav@601:      * The bytes written by this method may be
jaroslav@601:      * read by the <code>readShort</code> method
jaroslav@601:      * of interface <code>DataInput</code> , which
jaroslav@601:      * will then return a <code>short</code> equal
jaroslav@601:      * to <code>(short)v</code>.
jaroslav@601:      *
jaroslav@601:      * @param      v   the <code>short</code> value to be written.
jaroslav@601:      * @throws     IOException  if an I/O error occurs.
jaroslav@601:      */
jaroslav@601:     void writeShort(int v) throws IOException;
jaroslav@601: 
jaroslav@601:     /**
jaroslav@601:      * Writes a <code>char</code> value, which
jaroslav@601:      * is comprised of two bytes, to the
jaroslav@601:      * output stream.
jaroslav@601:      * The byte values to be written, in the  order
jaroslav@601:      * shown, are:
jaroslav@601:      * <p><pre><code>
jaroslav@601:      * (byte)(0xff &amp; (v &gt;&gt; 8))
jaroslav@601:      * (byte)(0xff &amp; v)
jaroslav@601:      * </code></pre><p>
jaroslav@601:      * The bytes written by this method may be
jaroslav@601:      * read by the <code>readChar</code> method
jaroslav@601:      * of interface <code>DataInput</code> , which
jaroslav@601:      * will then return a <code>char</code> equal
jaroslav@601:      * to <code>(char)v</code>.
jaroslav@601:      *
jaroslav@601:      * @param      v   the <code>char</code> value to be written.
jaroslav@601:      * @throws     IOException  if an I/O error occurs.
jaroslav@601:      */
jaroslav@601:     void writeChar(int v) throws IOException;
jaroslav@601: 
jaroslav@601:     /**
jaroslav@601:      * Writes an <code>int</code> value, which is
jaroslav@601:      * comprised of four bytes, to the output stream.
jaroslav@601:      * The byte values to be written, in the  order
jaroslav@601:      * shown, are:
jaroslav@601:      * <p><pre><code>
jaroslav@601:      * (byte)(0xff &amp; (v &gt;&gt; 24))
jaroslav@601:      * (byte)(0xff &amp; (v &gt;&gt; 16))
jaroslav@601:      * (byte)(0xff &amp; (v &gt;&gt; &#32; &#32;8))
jaroslav@601:      * (byte)(0xff &amp; v)
jaroslav@601:      * </code></pre><p>
jaroslav@601:      * The bytes written by this method may be read
jaroslav@601:      * by the <code>readInt</code> method of interface
jaroslav@601:      * <code>DataInput</code> , which will then
jaroslav@601:      * return an <code>int</code> equal to <code>v</code>.
jaroslav@601:      *
jaroslav@601:      * @param      v   the <code>int</code> value to be written.
jaroslav@601:      * @throws     IOException  if an I/O error occurs.
jaroslav@601:      */
jaroslav@601:     void writeInt(int v) throws IOException;
jaroslav@601: 
jaroslav@601:     /**
jaroslav@601:      * Writes a <code>long</code> value, which is
jaroslav@601:      * comprised of eight bytes, to the output stream.
jaroslav@601:      * The byte values to be written, in the  order
jaroslav@601:      * shown, are:
jaroslav@601:      * <p><pre><code>
jaroslav@601:      * (byte)(0xff &amp; (v &gt;&gt; 56))
jaroslav@601:      * (byte)(0xff &amp; (v &gt;&gt; 48))
jaroslav@601:      * (byte)(0xff &amp; (v &gt;&gt; 40))
jaroslav@601:      * (byte)(0xff &amp; (v &gt;&gt; 32))
jaroslav@601:      * (byte)(0xff &amp; (v &gt;&gt; 24))
jaroslav@601:      * (byte)(0xff &amp; (v &gt;&gt; 16))
jaroslav@601:      * (byte)(0xff &amp; (v &gt;&gt;  8))
jaroslav@601:      * (byte)(0xff &amp; v)
jaroslav@601:      * </code></pre><p>
jaroslav@601:      * The bytes written by this method may be
jaroslav@601:      * read by the <code>readLong</code> method
jaroslav@601:      * of interface <code>DataInput</code> , which
jaroslav@601:      * will then return a <code>long</code> equal
jaroslav@601:      * to <code>v</code>.
jaroslav@601:      *
jaroslav@601:      * @param      v   the <code>long</code> value to be written.
jaroslav@601:      * @throws     IOException  if an I/O error occurs.
jaroslav@601:      */
jaroslav@601:     void writeLong(long v) throws IOException;
jaroslav@601: 
jaroslav@601:     /**
jaroslav@601:      * Writes a <code>float</code> value,
jaroslav@601:      * which is comprised of four bytes, to the output stream.
jaroslav@601:      * It does this as if it first converts this
jaroslav@601:      * <code>float</code> value to an <code>int</code>
jaroslav@601:      * in exactly the manner of the <code>Float.floatToIntBits</code>
jaroslav@601:      * method  and then writes the <code>int</code>
jaroslav@601:      * value in exactly the manner of the  <code>writeInt</code>
jaroslav@601:      * method.  The bytes written by this method
jaroslav@601:      * may be read by the <code>readFloat</code>
jaroslav@601:      * method of interface <code>DataInput</code>,
jaroslav@601:      * which will then return a <code>float</code>
jaroslav@601:      * equal to <code>v</code>.
jaroslav@601:      *
jaroslav@601:      * @param      v   the <code>float</code> value to be written.
jaroslav@601:      * @throws     IOException  if an I/O error occurs.
jaroslav@601:      */
jaroslav@601:     void writeFloat(float v) throws IOException;
jaroslav@601: 
jaroslav@601:     /**
jaroslav@601:      * Writes a <code>double</code> value,
jaroslav@601:      * which is comprised of eight bytes, to the output stream.
jaroslav@601:      * It does this as if it first converts this
jaroslav@601:      * <code>double</code> value to a <code>long</code>
jaroslav@601:      * in exactly the manner of the <code>Double.doubleToLongBits</code>
jaroslav@601:      * method  and then writes the <code>long</code>
jaroslav@601:      * value in exactly the manner of the  <code>writeLong</code>
jaroslav@601:      * method. The bytes written by this method
jaroslav@601:      * may be read by the <code>readDouble</code>
jaroslav@601:      * method of interface <code>DataInput</code>,
jaroslav@601:      * which will then return a <code>double</code>
jaroslav@601:      * equal to <code>v</code>.
jaroslav@601:      *
jaroslav@601:      * @param      v   the <code>double</code> value to be written.
jaroslav@601:      * @throws     IOException  if an I/O error occurs.
jaroslav@601:      */
jaroslav@601:     void writeDouble(double v) throws IOException;
jaroslav@601: 
jaroslav@601:     /**
jaroslav@601:      * Writes a string to the output stream.
jaroslav@601:      * For every character in the string
jaroslav@601:      * <code>s</code>,  taken in order, one byte
jaroslav@601:      * is written to the output stream.  If
jaroslav@601:      * <code>s</code> is <code>null</code>, a <code>NullPointerException</code>
jaroslav@601:      * is thrown.<p>  If <code>s.length</code>
jaroslav@601:      * is zero, then no bytes are written. Otherwise,
jaroslav@601:      * the character <code>s[0]</code> is written
jaroslav@601:      * first, then <code>s[1]</code>, and so on;
jaroslav@601:      * the last character written is <code>s[s.length-1]</code>.
jaroslav@601:      * For each character, one byte is written,
jaroslav@601:      * the low-order byte, in exactly the manner
jaroslav@601:      * of the <code>writeByte</code> method . The
jaroslav@601:      * high-order eight bits of each character
jaroslav@601:      * in the string are ignored.
jaroslav@601:      *
jaroslav@601:      * @param      s   the string of bytes to be written.
jaroslav@601:      * @throws     IOException  if an I/O error occurs.
jaroslav@601:      */
jaroslav@601:     void writeBytes(String s) throws IOException;
jaroslav@601: 
jaroslav@601:     /**
jaroslav@601:      * Writes every character in the string <code>s</code>,
jaroslav@601:      * to the output stream, in order,
jaroslav@601:      * two bytes per character. If <code>s</code>
jaroslav@601:      * is <code>null</code>, a <code>NullPointerException</code>
jaroslav@601:      * is thrown.  If <code>s.length</code>
jaroslav@601:      * is zero, then no characters are written.
jaroslav@601:      * Otherwise, the character <code>s[0]</code>
jaroslav@601:      * is written first, then <code>s[1]</code>,
jaroslav@601:      * and so on; the last character written is
jaroslav@601:      * <code>s[s.length-1]</code>. For each character,
jaroslav@601:      * two bytes are actually written, high-order
jaroslav@601:      * byte first, in exactly the manner of the
jaroslav@601:      * <code>writeChar</code> method.
jaroslav@601:      *
jaroslav@601:      * @param      s   the string value to be written.
jaroslav@601:      * @throws     IOException  if an I/O error occurs.
jaroslav@601:      */
jaroslav@601:     void writeChars(String s) throws IOException;
jaroslav@601: 
jaroslav@601:     /**
jaroslav@601:      * Writes two bytes of length information
jaroslav@601:      * to the output stream, followed
jaroslav@601:      * by the
jaroslav@601:      * <a href="DataInput.html#modified-utf-8">modified UTF-8</a>
jaroslav@601:      * representation
jaroslav@601:      * of  every character in the string <code>s</code>.
jaroslav@601:      * If <code>s</code> is <code>null</code>,
jaroslav@601:      * a <code>NullPointerException</code> is thrown.
jaroslav@601:      * Each character in the string <code>s</code>
jaroslav@601:      * is converted to a group of one, two, or
jaroslav@601:      * three bytes, depending on the value of the
jaroslav@601:      * character.<p>
jaroslav@601:      * If a character <code>c</code>
jaroslav@601:      * is in the range <code>&#92;u0001</code> through
jaroslav@601:      * <code>&#92;u007f</code>, it is represented
jaroslav@601:      * by one byte:<p>
jaroslav@601:      * <pre>(byte)c </pre>  <p>
jaroslav@601:      * If a character <code>c</code> is <code>&#92;u0000</code>
jaroslav@601:      * or is in the range <code>&#92;u0080</code>
jaroslav@601:      * through <code>&#92;u07ff</code>, then it is
jaroslav@601:      * represented by two bytes, to be written
jaroslav@601:      * in the order shown:<p> <pre><code>
jaroslav@601:      * (byte)(0xc0 | (0x1f &amp; (c &gt;&gt; 6)))
jaroslav@601:      * (byte)(0x80 | (0x3f &amp; c))
jaroslav@601:      *  </code></pre>  <p> If a character
jaroslav@601:      * <code>c</code> is in the range <code>&#92;u0800</code>
jaroslav@601:      * through <code>uffff</code>, then it is
jaroslav@601:      * represented by three bytes, to be written
jaroslav@601:      * in the order shown:<p> <pre><code>
jaroslav@601:      * (byte)(0xe0 | (0x0f &amp; (c &gt;&gt; 12)))
jaroslav@601:      * (byte)(0x80 | (0x3f &amp; (c &gt;&gt;  6)))
jaroslav@601:      * (byte)(0x80 | (0x3f &amp; c))
jaroslav@601:      *  </code></pre>  <p> First,
jaroslav@601:      * the total number of bytes needed to represent
jaroslav@601:      * all the characters of <code>s</code> is
jaroslav@601:      * calculated. If this number is larger than
jaroslav@601:      * <code>65535</code>, then a <code>UTFDataFormatException</code>
jaroslav@601:      * is thrown. Otherwise, this length is written
jaroslav@601:      * to the output stream in exactly the manner
jaroslav@601:      * of the <code>writeShort</code> method;
jaroslav@601:      * after this, the one-, two-, or three-byte
jaroslav@601:      * representation of each character in the
jaroslav@601:      * string <code>s</code> is written.<p>  The
jaroslav@601:      * bytes written by this method may be read
jaroslav@601:      * by the <code>readUTF</code> method of interface
jaroslav@601:      * <code>DataInput</code> , which will then
jaroslav@601:      * return a <code>String</code> equal to <code>s</code>.
jaroslav@601:      *
jaroslav@601:      * @param      s   the string value to be written.
jaroslav@601:      * @throws     IOException  if an I/O error occurs.
jaroslav@601:      */
jaroslav@601:     void writeUTF(String s) throws IOException;
jaroslav@601: }