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	/*
	* Copyright (c) 2003, 2017, 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 javax.net.ssl;

	/**
	* An encapsulation of the result state produced by
	* {@code SSLEngine} I/O calls.
	*
	* <p> A {@code SSLEngine} provides a means for establishing
	* secure communication sessions between two peers. {@code SSLEngine}
	* operations typically consume bytes from an input buffer and produce
	* bytes in an output buffer. This class provides operational result
	* values describing the state of the {@code SSLEngine}, including
	* indications of what operations are needed to finish an
	* ongoing handshake. Lastly, it reports the number of bytes consumed
	* and produced as a result of this operation.
	*
	* @see SSLEngine
	* @see SSLEngine#wrap(ByteBuffer, ByteBuffer)
	* @see SSLEngine#unwrap(ByteBuffer, ByteBuffer)
	*
	* @author Brad R. Wetmore
	* @since 1.5
	*/

	public class SSLEngineResult {

	/**
	* An {@code SSLEngineResult} enum describing the overall result
	* of the {@code SSLEngine} operation.
	*
	* The {@code Status} value does not reflect the
	* state of a {@code SSLEngine} handshake currently
	* in progress. The {@code SSLEngineResult's HandshakeStatus}
	* should be consulted for that information.
	*
	* @author Brad R. Wetmore
	* @since 1.5
	*/
	public static enum Status {

	/**
	* The {@code SSLEngine} was not able to unwrap the
	* incoming data because there were not enough source bytes
	* available to make a complete packet.
	*
	* <P>
	* Repeat the call once more bytes are available.
	*/
	BUFFER_UNDERFLOW,

	/**
	* The {@code SSLEngine} was not able to process the
	* operation because there are not enough bytes available in the
	* destination buffer to hold the result.
	* <P>
	* Repeat the call once more bytes are available.
	*
	* @see SSLSession#getPacketBufferSize()
	* @see SSLSession#getApplicationBufferSize()
	*/
	BUFFER_OVERFLOW,

	/**
	* The {@code SSLEngine} completed the operation, and
	* is available to process similar calls.
	*/
	OK,

	/**
	* The operation just closed this side of the
	* {@code SSLEngine}, or the operation
	* could not be completed because it was already closed.
	*/
	CLOSED;
	}

	/**
	* An {@code SSLEngineResult} enum describing the current
	* handshaking state of this {@code SSLEngine}.
	*
	* @author Brad R. Wetmore
	* @since 1.5
	*/
	public static enum HandshakeStatus {

	/**
	* The {@code SSLEngine} is not currently handshaking.
	*/
	NOT_HANDSHAKING,

	/**
	* The {@code SSLEngine} has just finished handshaking.
	* <P>
	* This value is only generated by a call to
	* {@code SSLEngine.wrap()/unwrap()} when that call
	* finishes a handshake. It is never generated by
	* {@code SSLEngine.getHandshakeStatus()}.
	*
	* @see SSLEngine#wrap(ByteBuffer, ByteBuffer)
	* @see SSLEngine#unwrap(ByteBuffer, ByteBuffer)
	* @see SSLEngine#getHandshakeStatus()
	*/
	FINISHED,

	/**
	* The {@code SSLEngine} needs the results of one (or more)
	* delegated tasks before handshaking can continue.
	*
	* @see SSLEngine#getDelegatedTask()
	*/
	NEED_TASK,

	/**
	* The {@code SSLEngine} must send data to the remote side
	* before handshaking can continue, so {@code SSLEngine.wrap()}
	* should be called.
	*
	* @see SSLEngine#wrap(ByteBuffer, ByteBuffer)
	*/
	NEED_WRAP,

	/**
	* The {@code SSLEngine} needs to receive data from the
	* remote side before handshaking can continue.
	*/
	NEED_UNWRAP,

	/**
	* The {@code SSLEngine} needs to unwrap before handshaking can
	* continue.
	* <P>
	* This value is used to indicate that not-yet-interpreted data
	* has been previously received from the remote side, and does
	* not need to be received again.
	* <P>
	* This handshake status only applies to DTLS.
	*
	* @since 9
	*/
	NEED_UNWRAP_AGAIN;
	}


	private final Status status;
	private final HandshakeStatus handshakeStatus;
	private final int bytesConsumed;
	private final int bytesProduced;
	private final long sequenceNumber;

	/**
	* Initializes a new instance of this class.
	*
	* @param status
	* the return value of the operation.
	*
	* @param handshakeStatus
	* the current handshaking status.
	*
	* @param bytesConsumed
	* the number of bytes consumed from the source ByteBuffer
	*
	* @param bytesProduced
	* the number of bytes placed into the destination ByteBuffer
	*
	* @throws IllegalArgumentException
	* if the {@code status} or {@code handshakeStatus}
	* arguments are null, or if {@code bytesConsumed} or
	* {@code bytesProduced} is negative.
	*/
	public SSLEngineResult(Status status, HandshakeStatus handshakeStatus,
	int bytesConsumed, int bytesProduced) {
	this(status, handshakeStatus, bytesConsumed, bytesProduced, -1);
	}

	/**
	* Initializes a new instance of this class.
	*
	* @param status
	* the return value of the operation.
	*
	* @param handshakeStatus
	* the current handshaking status.
	*
	* @param bytesConsumed
	* the number of bytes consumed from the source ByteBuffer
	*
	* @param bytesProduced
	* the number of bytes placed into the destination ByteBuffer
	*
	* @param sequenceNumber
	* the sequence number (unsigned long) of the produced or
	* consumed SSL/TLS/DTLS record, or {@code -1L} if no record
	* produced or consumed
	*
	* @throws IllegalArgumentException
	* if the {@code status} or {@code handshakeStatus}
	* arguments are null, or if {@code bytesConsumed} or
	* {@code bytesProduced} is negative
	*
	* @since 9
	*/
	public SSLEngineResult(Status status, HandshakeStatus handshakeStatus,
	int bytesConsumed, int bytesProduced, long sequenceNumber) {

	if ((status == null) \|\| (handshakeStatus == null) \|\|
	(bytesConsumed < 0) \|\| (bytesProduced < 0)) {
	throw new IllegalArgumentException("Invalid Parameter(s)");
	}

	this.status = status;
	this.handshakeStatus = handshakeStatus;
	this.bytesConsumed = bytesConsumed;
	this.bytesProduced = bytesProduced;
	this.sequenceNumber = sequenceNumber;
	}

	/**
	* Gets the return value of this {@code SSLEngine} operation.
	*
	* @return the return value
	*/
	public final Status getStatus() {
	return status;
	}

	/**
	* Gets the handshake status of this {@code SSLEngine}
	* operation.
	*
	* @return the handshake status
	*/
	public final HandshakeStatus getHandshakeStatus() {
	return handshakeStatus;
	}

	/**
	* Returns the number of bytes consumed from the input buffer.
	*
	* @return the number of bytes consumed.
	*/
	public final int bytesConsumed() {
	return bytesConsumed;
	}

	/**
	* Returns the number of bytes written to the output buffer.
	*
	* @return the number of bytes produced
	*/
	public final int bytesProduced() {
	return bytesProduced;
	}

	/**
	* Returns the sequence number of the produced or consumed SSL/TLS/DTLS
	* record (optional operation).
	*
	* @apiNote Note that sequence number is an unsigned long and cannot
	* exceed {@code -1L}. It is desired to use the unsigned
	* long comparing mode for comparison of unsigned long values
	* (see also {@link java.lang.Long#compareUnsigned(long, long)
	* Long.compareUnsigned()}).
	* <P>
	* For DTLS protocols, the first 16 bits of the sequence
	* number is a counter value (epoch) that is incremented on
	* every cipher state change. The remaining 48 bits on the
	* right side of the sequence number represents the sequence
	* of the record, which is maintained separately for each epoch.
	*
	* @implNote It is recommended that providers should never allow the
	* sequence number incremented to {@code -1L}. If the sequence
	* number is close to wrapping, renegotiate should be requested,
	* otherwise the connection should be closed immediately.
	* This should be carried on automatically by the underlying
	* implementation.
	*
	* @return the sequence number of the produced or consumed SSL/TLS/DTLS
	* record; or {@code -1L} if no record is produced or consumed,
	* or this operation is not supported by the underlying provider
	*
	* @see java.lang.Long#compareUnsigned(long, long)
	*
	* @since 9
	*/
	public final long sequenceNumber() {
	return sequenceNumber;
	}

	/**
	* Returns a String representation of this object.
	*/
	@Override
	public String toString() {
	return ("Status = " + status +
	" HandshakeStatus = " + handshakeStatus +
	"\nbytesConsumed = " + bytesConsumed +
	" bytesProduced = " + bytesProduced +
	(sequenceNumber == -1 ? "" :
	" sequenceNumber = " + Long.toUnsignedString(sequenceNumber)));
	}
	}

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