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	/*
	* Copyright (c) 1994, 2016, 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 sun.net;

	import java.io.*;
	import java.net.Socket;
	import java.net.InetAddress;
	import java.net.InetSocketAddress;
	import java.net.UnknownHostException;
	import java.net.Proxy;
	import java.util.Arrays;
	import java.security.AccessController;
	import java.security.PrivilegedAction;

	/**
	* This is the base class for network clients.
	*
	* @author Jonathan Payne
	*/
	public class NetworkClient {
	/* Default value of read timeout, if not specified (infinity) */
	public static final int DEFAULT_READ_TIMEOUT = -1;

	/* Default value of connect timeout, if not specified (infinity) */
	public static final int DEFAULT_CONNECT_TIMEOUT = -1;

	protected Proxy proxy = Proxy.NO_PROXY;
	/** Socket for communicating with server. */
	protected Socket serverSocket = null;

	/** Stream for printing to the server. */
	public PrintStream serverOutput;

	/** Buffered stream for reading replies from server. */
	public InputStream serverInput;

	protected static int defaultSoTimeout;
	protected static int defaultConnectTimeout;

	protected int readTimeout = DEFAULT_READ_TIMEOUT;
	protected int connectTimeout = DEFAULT_CONNECT_TIMEOUT;
	/* Name of encoding to use for output */
	protected static String encoding;

	static {
	final int vals[] = {0, 0};
	final String encs[] = { null };

	AccessController.doPrivileged(
	new PrivilegedAction<>() {
	public Void run() {
	vals[0] = Integer.getInteger("sun.net.client.defaultReadTimeout", 0).intValue();
	vals[1] = Integer.getInteger("sun.net.client.defaultConnectTimeout", 0).intValue();
	encs[0] = System.getProperty("file.encoding", "ISO8859_1");
	return null;
	}
	});
	if (vals[0] != 0) {
	defaultSoTimeout = vals[0];
	}
	if (vals[1] != 0) {
	defaultConnectTimeout = vals[1];
	}

	encoding = encs[0];
	try {
	if (!isASCIISuperset (encoding)) {
	encoding = "ISO8859_1";
	}
	} catch (Exception e) {
	encoding = "ISO8859_1";
	}
	}


	/**
	* Test the named character encoding to verify that it converts ASCII
	* characters correctly. We have to use an ASCII based encoding, or else
	* the NetworkClients will not work correctly in EBCDIC based systems.
	* However, we cannot just use ASCII or ISO8859_1 universally, because in
	* Asian locales, non-ASCII characters may be embedded in otherwise
	* ASCII based protocols (eg. HTTP). The specifications (RFC2616, 2398)
	* are a little ambiguous in this matter. For instance, RFC2398 [part 2.1]
	* says that the HTTP request URI should be escaped using a defined
	* mechanism, but there is no way to specify in the escaped string what
	* the original character set is. It is not correct to assume that
	* UTF-8 is always used (as in URLs in HTML 4.0). For this reason,
	* until the specifications are updated to deal with this issue more
	* comprehensively, and more importantly, HTTP servers are known to
	* support these mechanisms, we will maintain the current behavior
	* where it is possible to send non-ASCII characters in their original
	* unescaped form.
	*/
	private static boolean isASCIISuperset (String encoding) throws Exception {
	String chkS = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ"+
	"abcdefghijklmnopqrstuvwxyz-_.!~*'();/?:@&=+$,";

	// Expected byte sequence for string above
	byte[] chkB = { 48,49,50,51,52,53,54,55,56,57,65,66,67,68,69,70,71,72,
	73,74,75,76,77,78,79,80,81,82,83,84,85,86,87,88,89,90,97,98,99,
	100,101,102,103,104,105,106,107,108,109,110,111,112,113,114,
	115,116,117,118,119,120,121,122,45,95,46,33,126,42,39,40,41,59,
	47,63,58,64,38,61,43,36,44};

	byte[] b = chkS.getBytes (encoding);
	return Arrays.equals (b, chkB);
	}

	/** Open a connection to the server. */
	public void openServer(String server, int port)
	throws IOException, UnknownHostException {
	if (serverSocket != null)
	closeServer();
	serverSocket = doConnect (server, port);
	try {
	serverOutput = new PrintStream(new BufferedOutputStream(
	serverSocket.getOutputStream()),
	true, encoding);
	} catch (UnsupportedEncodingException e) {
	throw new InternalError(encoding +"encoding not found", e);
	}
	serverInput = new BufferedInputStream(serverSocket.getInputStream());
	}

	/**
	* Return a socket connected to the server, with any
	* appropriate options pre-established
	*/
	protected Socket doConnect (String server, int port)
	throws IOException, UnknownHostException {
	Socket s;
	if (proxy != null) {
	if (proxy.type() == Proxy.Type.SOCKS) {
	s = AccessController.doPrivileged(
	new PrivilegedAction<>() {
	public Socket run() {
	return new Socket(proxy);
	}});
	} else if (proxy.type() == Proxy.Type.DIRECT) {
	s = createSocket();
	} else {
	// Still connecting through a proxy
	// server & port will be the proxy address and port
	s = new Socket(Proxy.NO_PROXY);
	}
	} else {
	s = createSocket();
	}

	// Instance specific timeouts do have priority, that means
	// connectTimeout & readTimeout (-1 means not set)
	// Then global default timeouts
	// Then no timeout.
	if (connectTimeout >= 0) {
	s.connect(new InetSocketAddress(server, port), connectTimeout);
	} else {
	if (defaultConnectTimeout > 0) {
	s.connect(new InetSocketAddress(server, port), defaultConnectTimeout);
	} else {
	s.connect(new InetSocketAddress(server, port));
	}
	}
	if (readTimeout >= 0)
	s.setSoTimeout(readTimeout);
	else if (defaultSoTimeout > 0) {
	s.setSoTimeout(defaultSoTimeout);
	}
	return s;
	}

	/**
	* The following method, createSocket, is provided to allow the
	* https client to override it so that it may use its socket factory
	* to create the socket.
	*/
	protected Socket createSocket() throws IOException {
	return new java.net.Socket(Proxy.NO_PROXY); // direct connection
	}

	protected InetAddress getLocalAddress() throws IOException {
	if (serverSocket == null)
	throw new IOException("not connected");
	return AccessController.doPrivileged(
	new PrivilegedAction<>() {
	public InetAddress run() {
	return serverSocket.getLocalAddress();

	}
	});
	}

	/** Close an open connection to the server. */
	public void closeServer() throws IOException {
	if (! serverIsOpen()) {
	return;
	}
	serverSocket.close();
	serverSocket = null;
	serverInput = null;
	serverOutput = null;
	}

	/** Return server connection status */
	public boolean serverIsOpen() {
	return serverSocket != null;
	}

	/** Create connection with host <i>host</i> on port <i>port</i> */
	public NetworkClient(String host, int port) throws IOException {
	openServer(host, port);
	}

	public NetworkClient() {}

	public void setConnectTimeout(int timeout) {
	connectTimeout = timeout;
	}

	public int getConnectTimeout() {
	return connectTimeout;
	}

	/**
	* Sets the read timeout.
	*
	* Note: Public URLConnection (and protocol specific implementations)
	* protect against negative timeout values being set. This implementation,
	* and protocol specific implementations, use -1 to represent the default
	* read timeout.
	*
	* This method may be invoked with the default timeout value when the
	* protocol handler is trying to reset the timeout after doing a
	* potentially blocking internal operation, e.g. cleaning up unread
	* response data, buffering error stream response data, etc
	*/
	public void setReadTimeout(int timeout) {
	if (timeout == DEFAULT_READ_TIMEOUT)
	timeout = defaultSoTimeout;

	if (serverSocket != null && timeout >= 0) {
	try {
	serverSocket.setSoTimeout(timeout);
	} catch(IOException e) {
	// We tried...
	}
	}
	readTimeout = timeout;
	}

	public int getReadTimeout() {
	return readTimeout;
	}
	}

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