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	/*
	* Copyright (c) 1994, 2021, 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;

	/**
	* A data output stream lets an application write primitive Java data
	* types to an output stream in a portable way. An application can
	* then use a data input stream to read the data back in.
	* <p>
	* A DataOutputStream is not safe for use by multiple concurrent
	* threads. If a DataOutputStream is to be used by more than one
	* thread then access to the data output stream should be controlled
	* by appropriate synchronization.
	*
	* @see java.io.DataInputStream
	* @since 1.0
	*/
	public class DataOutputStream extends FilterOutputStream implements DataOutput {
	/**
	* The number of bytes written to the data output stream so far.
	* If this counter overflows, it will be wrapped to Integer.MAX_VALUE.
	*/
	protected int written;

	/**
	* bytearr is initialized on demand by writeUTF
	*/
	private byte[] bytearr = null;

	private final byte[] writeBuffer = new byte[8];

	/**
	* Creates a new data output stream to write data to the specified
	* underlying output stream. The counter {@code written} is
	* set to zero.
	*
	* @param out the underlying output stream, to be saved for later
	* use.
	* @see java.io.FilterOutputStream#out
	*/
	public DataOutputStream(OutputStream out) {
	super(out);
	}

	/**
	* Increases the written counter by the specified value
	* until it reaches Integer.MAX_VALUE.
	*/
	private void incCount(int value) {
	int temp = written + value;
	if (temp < 0) {
	temp = Integer.MAX_VALUE;
	}
	written = temp;
	}

	/**
	* Writes the specified byte (the low eight bits of the argument
	* {@code b}) to the underlying output stream. If no exception
	* is thrown, the counter {@code written} is incremented by
	* {@code 1}.
	* <p>
	* Implements the {@code write} method of {@code OutputStream}.
	*
	* @param b the {@code byte} to be written.
	* @throws IOException if an I/O error occurs.
	* @see java.io.FilterOutputStream#out
	*/
	public synchronized void write(int b) throws IOException {
	out.write(b);
	incCount(1);
	}

	/**
	* Writes {@code len} bytes from the specified byte array
	* starting at offset {@code off} to the underlying output stream.
	* If no exception is thrown, the counter {@code written} is
	* incremented by {@code len}.
	*
	* @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.
	* @see java.io.FilterOutputStream#out
	*/
	public synchronized void write(byte b[], int off, int len)
	throws IOException
	{
	out.write(b, off, len);
	incCount(len);
	}

	/**
	* Flushes this data output stream. This forces any buffered output
	* bytes to be written out to the stream.
	* <p>
	* The {@code flush} method of {@code DataOutputStream}
	* calls the {@code flush} method of its underlying output stream.
	*
	* @throws IOException if an I/O error occurs.
	* @see java.io.FilterOutputStream#out
	* @see java.io.OutputStream#flush()
	*/
	public void flush() throws IOException {
	out.flush();
	}

	/**
	* Writes a {@code boolean} to the underlying output stream as
	* a 1-byte value. The value {@code true} is written out as the
	* value {@code (byte)1}; the value {@code false} is
	* written out as the value {@code (byte)0}. If no exception is
	* thrown, the counter {@code written} is incremented by
	* {@code 1}.
	*
	* @param v a {@code boolean} value to be written.
	* @throws IOException if an I/O error occurs.
	* @see java.io.FilterOutputStream#out
	*/
	public final void writeBoolean(boolean v) throws IOException {
	out.write(v ? 1 : 0);
	incCount(1);
	}

	/**
	* Writes out a {@code byte} to the underlying output stream as
	* a 1-byte value. If no exception is thrown, the counter
	* {@code written} is incremented by {@code 1}.
	*
	* @param v a {@code byte} value to be written.
	* @throws IOException if an I/O error occurs.
	* @see java.io.FilterOutputStream#out
	*/
	public final void writeByte(int v) throws IOException {
	out.write(v);
	incCount(1);
	}

	/**
	* Writes a {@code short} to the underlying output stream as two
	* bytes, high byte first. If no exception is thrown, the counter
	* {@code written} is incremented by {@code 2}.
	*
	* @param v a {@code short} to be written.
	* @throws IOException if an I/O error occurs.
	* @see java.io.FilterOutputStream#out
	*/
	public final void writeShort(int v) throws IOException {
	writeBuffer[0] = (byte)(v >>> 8);
	writeBuffer[1] = (byte)(v >>> 0);
	out.write(writeBuffer, 0, 2);
	incCount(2);
	}

	/**
	* Writes a {@code char} to the underlying output stream as a
	* 2-byte value, high byte first. If no exception is thrown, the
	* counter {@code written} is incremented by {@code 2}.
	*
	* @param v a {@code char} value to be written.
	* @throws IOException if an I/O error occurs.
	* @see java.io.FilterOutputStream#out
	*/
	public final void writeChar(int v) throws IOException {
	writeBuffer[0] = (byte)(v >>> 8);
	writeBuffer[1] = (byte)(v >>> 0);
	out.write(writeBuffer, 0, 2);
	incCount(2);
	}

	/**
	* Writes an {@code int} to the underlying output stream as four
	* bytes, high byte first. If no exception is thrown, the counter
	* {@code written} is incremented by {@code 4}.
	*
	* @param v an {@code int} to be written.
	* @throws IOException if an I/O error occurs.
	* @see java.io.FilterOutputStream#out
	*/
	public final void writeInt(int v) throws IOException {
	writeBuffer[0] = (byte)(v >>> 24);
	writeBuffer[1] = (byte)(v >>> 16);
	writeBuffer[2] = (byte)(v >>> 8);
	writeBuffer[3] = (byte)(v >>> 0);
	out.write(writeBuffer, 0, 4);
	incCount(4);
	}

	/**
	* Writes a {@code long} to the underlying output stream as eight
	* bytes, high byte first. In no exception is thrown, the counter
	* {@code written} is incremented by {@code 8}.
	*
	* @param v a {@code long} to be written.
	* @throws IOException if an I/O error occurs.
	* @see java.io.FilterOutputStream#out
	*/
	public final void writeLong(long v) throws IOException {
	writeBuffer[0] = (byte)(v >>> 56);
	writeBuffer[1] = (byte)(v >>> 48);
	writeBuffer[2] = (byte)(v >>> 40);
	writeBuffer[3] = (byte)(v >>> 32);
	writeBuffer[4] = (byte)(v >>> 24);
	writeBuffer[5] = (byte)(v >>> 16);
	writeBuffer[6] = (byte)(v >>> 8);
	writeBuffer[7] = (byte)(v >>> 0);
	out.write(writeBuffer, 0, 8);
	incCount(8);
	}

	/**
	* Converts the float argument to an {@code int} using the
	* {@code floatToIntBits} method in class {@code Float},
	* and then writes that {@code int} value to the underlying
	* output stream as a 4-byte quantity, high byte first. If no
	* exception is thrown, the counter {@code written} is
	* incremented by {@code 4}.
	*
	* @param v a {@code float} value to be written.
	* @throws IOException if an I/O error occurs.
	* @see java.io.FilterOutputStream#out
	* @see java.lang.Float#floatToIntBits(float)
	*/
	public final void writeFloat(float v) throws IOException {
	writeInt(Float.floatToIntBits(v));
	}

	/**
	* Converts the double argument to a {@code long} using the
	* {@code doubleToLongBits} method in class {@code Double},
	* and then writes that {@code long} value to the underlying
	* output stream as an 8-byte quantity, high byte first. If no
	* exception is thrown, the counter {@code written} is
	* incremented by {@code 8}.
	*
	* @param v a {@code double} value to be written.
	* @throws IOException if an I/O error occurs.
	* @see java.io.FilterOutputStream#out
	* @see java.lang.Double#doubleToLongBits(double)
	*/
	public final void writeDouble(double v) throws IOException {
	writeLong(Double.doubleToLongBits(v));
	}

	/**
	* Writes out the string to the underlying output stream as a
	* sequence of bytes. Each character in the string is written out, in
	* sequence, by discarding its high eight bits. If no exception is
	* thrown, the counter {@code written} is incremented by the
	* length of {@code s}.
	*
	* @param s a string of bytes to be written.
	* @throws IOException if an I/O error occurs.
	* @see java.io.FilterOutputStream#out
	*/
	public final void writeBytes(String s) throws IOException {
	int len = s.length();
	for (int i = 0 ; i < len ; i++) {
	out.write((byte)s.charAt(i));
	}
	incCount(len);
	}

	/**
	* Writes a string to the underlying output stream as a sequence of
	* characters. Each character is written to the data output stream as
	* if by the {@code writeChar} method. If no exception is
	* thrown, the counter {@code written} is incremented by twice
	* the length of {@code s}.
	*
	* @param s a {@code String} value to be written.
	* @throws IOException if an I/O error occurs.
	* @see java.io.DataOutputStream#writeChar(int)
	* @see java.io.FilterOutputStream#out
	*/
	public final void writeChars(String s) throws IOException {
	int len = s.length();
	for (int i = 0 ; i < len ; i++) {
	int v = s.charAt(i);
	writeBuffer[0] = (byte)(v >>> 8);
	writeBuffer[1] = (byte)(v >>> 0);
	out.write(writeBuffer, 0, 2);
	}
	incCount(len * 2);
	}

	/**
	* Writes a string to the underlying output stream using
	* <a href="DataInput.html#modified-utf-8">modified UTF-8</a>
	* encoding in a machine-independent manner.
	* <p>
	* First, two bytes are written to the output stream as if by the
	* {@code writeShort} method giving the number of bytes to
	* follow. This value is the number of bytes actually written out,
	* not the length of the string. Following the length, each character
	* of the string is output, in sequence, using the modified UTF-8 encoding
	* for the character. If no exception is thrown, the counter
	* {@code written} is incremented by the total number of
	* bytes written to the output stream. This will be at least two
	* plus the length of {@code str}, and at most two plus
	* thrice the length of {@code str}.
	*
	* @param str a string to be written.
	* @throws UTFDataFormatException if the modified UTF-8 encoding of
	* {@code str} would exceed 65535 bytes in length
	* @throws IOException if some other I/O error occurs.
	* @see #writeChars(String)
	*/
	public final void writeUTF(String str) throws IOException {
	writeUTF(str, this);
	}

	/**
	* Writes a string to the specified DataOutput using
	* <a href="DataInput.html#modified-utf-8">modified UTF-8</a>
	* encoding in a machine-independent manner.
	* <p>
	* First, two bytes are written to out as if by the {@code writeShort}
	* method giving the number of bytes to follow. This value is the number of
	* bytes actually written out, not the length of the string. Following the
	* length, each character of the string is output, in sequence, using the
	* modified UTF-8 encoding for the character. If no exception is thrown, the
	* counter {@code written} is incremented by the total number of
	* bytes written to the output stream. This will be at least two
	* plus the length of {@code str}, and at most two plus
	* thrice the length of {@code str}.
	*
	* @param str a string to be written.
	* @param out destination to write to
	* @return The number of bytes written out.
	* @throws UTFDataFormatException if the modified UTF-8 encoding of
	* {@code str} would exceed 65535 bytes in length
	* @throws IOException if some other I/O error occurs.
	*/
	static int writeUTF(String str, DataOutput out) throws IOException {
	final int strlen = str.length();
	int utflen = strlen; // optimized for ASCII

	for (int i = 0; i < strlen; i++) {
	int c = str.charAt(i);
	if (c >= 0x80 \|\| c == 0)
	utflen += (c >= 0x800) ? 2 : 1;
	}

	if (utflen > 65535 \|\| /* overflow */ utflen < strlen)
	throw new UTFDataFormatException(tooLongMsg(str, utflen));

	final byte[] bytearr;
	if (out instanceof DataOutputStream dos) {
	if (dos.bytearr == null \|\| (dos.bytearr.length < (utflen + 2)))
	dos.bytearr = new byte[(utflen*2) + 2];
	bytearr = dos.bytearr;
	} else {
	bytearr = new byte[utflen + 2];
	}

	int count = 0;
	bytearr[count++] = (byte) ((utflen >>> 8) & 0xFF);
	bytearr[count++] = (byte) ((utflen >>> 0) & 0xFF);

	int i = 0;
	for (i = 0; i < strlen; i++) { // optimized for initial run of ASCII
	int c = str.charAt(i);
	if (c >= 0x80 \|\| c == 0) break;
	bytearr[count++] = (byte) c;
	}

	for (; i < strlen; i++) {
	int c = str.charAt(i);
	if (c < 0x80 && c != 0) {
	bytearr[count++] = (byte) c;
	} else if (c >= 0x800) {
	bytearr[count++] = (byte) (0xE0 \| ((c >> 12) & 0x0F));
	bytearr[count++] = (byte) (0x80 \| ((c >> 6) & 0x3F));
	bytearr[count++] = (byte) (0x80 \| ((c >> 0) & 0x3F));
	} else {
	bytearr[count++] = (byte) (0xC0 \| ((c >> 6) & 0x1F));
	bytearr[count++] = (byte) (0x80 \| ((c >> 0) & 0x3F));
	}
	}
	out.write(bytearr, 0, utflen + 2);
	return utflen + 2;
	}

	private static String tooLongMsg(String s, int bits32) {
	int slen = s.length();
	String head = s.substring(0, 8);
	String tail = s.substring(slen - 8, slen);
	// handle int overflow with max 3x expansion
	long actualLength = (long)slen + Integer.toUnsignedLong(bits32 - slen);
	return "encoded string (" + head + "..." + tail + ") too long: "
	+ actualLength + " bytes";
	}

	/**
	* Returns the current value of the counter {@code written},
	* the number of bytes written to this data output stream so far.
	* If the counter overflows, it will be wrapped to Integer.MAX_VALUE.
	*
	* @return the value of the {@code written} field.
	* @see java.io.DataOutputStream#written
	*/
	public final int size() {
	return written;
	}
	}

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