Java tutorial
/* * Copyright 2012 The Netty Project * * The Netty Project licenses this file to you under the Apache License, * version 2.0 (the "License"); you may not use this file except in compliance * with the License. You may obtain a copy of the License at: * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the * License for the specific language governing permissions and limitations * under the License. */ package io.netty.handler.codec.socks; import io.netty.buffer.ByteBuf; import io.netty.util.CharsetUtil; import io.netty.util.NetUtil; import io.netty.util.internal.ObjectUtil; import java.net.IDN; /** * An socks cmd request. * * @see SocksCmdResponse * @see SocksCmdRequestDecoder */ public final class SocksCmdRequest extends SocksRequest { private final SocksCmdType cmdType; private final SocksAddressType addressType; private final String host; private final int port; public SocksCmdRequest(SocksCmdType cmdType, SocksAddressType addressType, String host, int port) { super(SocksRequestType.CMD); ObjectUtil.checkNotNull(cmdType, "cmdType"); ObjectUtil.checkNotNull(addressType, "addressType"); ObjectUtil.checkNotNull(host, "host"); switch (addressType) { case IPv4: if (!NetUtil.isValidIpV4Address(host)) { throw new IllegalArgumentException(host + " is not a valid IPv4 address"); } break; case DOMAIN: String asciiHost = IDN.toASCII(host); if (asciiHost.length() > 255) { throw new IllegalArgumentException(host + " IDN: " + asciiHost + " exceeds 255 char limit"); } host = asciiHost; break; case IPv6: if (!NetUtil.isValidIpV6Address(host)) { throw new IllegalArgumentException(host + " is not a valid IPv6 address"); } break; case UNKNOWN: break; } if (port <= 0 || port >= 65536) { throw new IllegalArgumentException(port + " is not in bounds 0 < x < 65536"); } this.cmdType = cmdType; this.addressType = addressType; this.host = host; this.port = port; } /** * Returns the {@link SocksCmdType} of this {@link SocksCmdRequest} * * @return The {@link SocksCmdType} of this {@link SocksCmdRequest} */ public SocksCmdType cmdType() { return cmdType; } /** * Returns the {@link SocksAddressType} of this {@link SocksCmdRequest} * * @return The {@link SocksAddressType} of this {@link SocksCmdRequest} */ public SocksAddressType addressType() { return addressType; } /** * Returns host that is used as a parameter in {@link SocksCmdType} * * @return host that is used as a parameter in {@link SocksCmdType} */ public String host() { return addressType == SocksAddressType.DOMAIN ? IDN.toUnicode(host) : host; } /** * Returns port that is used as a parameter in {@link SocksCmdType} * * @return port that is used as a parameter in {@link SocksCmdType} */ public int port() { return port; } @Override public void encodeAsByteBuf(ByteBuf byteBuf) { byteBuf.writeByte(protocolVersion().byteValue()); byteBuf.writeByte(cmdType.byteValue()); byteBuf.writeByte(0x00); byteBuf.writeByte(addressType.byteValue()); switch (addressType) { case IPv4: { byteBuf.writeBytes(NetUtil.createByteArrayFromIpAddressString(host)); byteBuf.writeShort(port); break; } case DOMAIN: { byteBuf.writeByte(host.length()); byteBuf.writeCharSequence(host, CharsetUtil.US_ASCII); byteBuf.writeShort(port); break; } case IPv6: { byteBuf.writeBytes(NetUtil.createByteArrayFromIpAddressString(host)); byteBuf.writeShort(port); break; } } } }