Java Socket应答与HTTP服务器的瓜葛

Java Socket应答与HTTP服务器的瓜葛

Java Socket应答一直伴随着我们的编程生活，在不断的发展中有很多知识需要我们学习。下面我们就先来看看有关JavaSocket应答的代码，有点长，但是看下去就会让你豁然开朗。

HTTP/1.1表示这个HTTP服务器是1.1版，200是服务器对客户请求的应答状态码，OK是对应答状态码的解释，之后是这个文档的元信息和文档正文。(相关应答状态码和元信息的解释请参阅Inetrnet标准草案:RFC2616)。

1. Http.java
2. importjava.net.*;
3. importjava.io.*;
4. importjava.util.Properties;
5. importjava.util.Enumeration;
6. publicclassHttp{
7. protectedSocketclient;
8. protectedBufferedOutputStreamsender;
9. protectedBufferedInputStreamreceiver;
10. protectedByteArrayInputStreambyteStream;
11. protectedURLtarget;
12. privateintresponseCode=-1;
13. privateStringresponseMessage="";
14. privateStringserverVersion="";
15. privatePropertiesheader=newProperties();
16. publicHttp(){}
17. publicHttp(Stringurl){
18. GET(url);
19. }
20. /*GET方法根据URL，会请求文件、数据库查询结果、程序运行结果等多种内容*/
21. publicvoidGET(Stringurl){
22. try{
23. checkHTTP(url);
24. openServer(target.getHost(),target.getPort());
25. Stringcmd="GET"+getURLFormat(target)+"HTTP/1.0\r\n"
26. +getBaseHeads()+"\r\n";
27. sendMessage(cmd);
28. receiveMessage();
29. }catch(ProtocolExceptionp){
30. p.printStackTrace();
31. return;
32. }catch(UnknownHostExceptione){
33. e.printStackTrace();
34. return;
35. }catch(IOExceptioni){
36. i.printStackTrace();
37. return;
38. }
39. }
40. /*
41. *HEAD方法只请求URL的元信息，不包括URL本身。若怀疑本机和服务器上的
42. *文件相同，用这个方法检查最快捷有效。
43. */
44. publicvoidHEAD(Stringurl){
45. try{
46. checkHTTP(url);
47. openServer(target.getHost(),target.getPort());
48. Stringcmd="HEAD"+getURLFormat(target)+"HTTP/1.0\r\n"
49. +getBaseHeads()+"\r\n";
50. sendMessage(cmd);
51. receiveMessage();
52. }catch(ProtocolExceptionp){
53. p.printStackTrace();
54. return;
55. }catch(UnknownHostExceptione){
56. e.printStackTrace();
57. return;
58. }catch(IOExceptioni){
59. i.printStackTrace();
60. return;
61. }
62. }
63. /*
64. *POST方法是向服务器传送数据，以便服务器做出相应的处理。例如网页上常用的
65. *提交表格。
66. */
67. publicvoidPOST(Stringurl,Stringcontent){
68. try{
69. checkHTTP(url);
70. openServer(target.getHost(),target.getPort());
71. Stringcmd="POST"+getURLFormat(target)+"HTTP/1.0\r\n"+getBaseHeads();
72. cmd+="Content-type:application/x-www-form-urlencoded\r\n";
73. cmd+="Content-length:"+content.length()+"\r\n\r\n";
74. cmd+=content+"\r\n";
75. sendMessage(cmd);
76. receiveMessage();
77. }catch(ProtocolExceptionp){
78. p.printStackTrace();
79. return;
80. }catch(UnknownHostExceptione){
81. e.printStackTrace();
82. return;
83. }catch(IOExceptioni){
84. i.printStackTrace();
85. return;
86. }
87. }
88. protectedvoidcheckHTTP(Stringurl)throwsProtocolException{
89. try{
90. URLtarget=newURL(url);
91. if(target==null||!target.getProtocol().toUpperCase().equals("HTTP"))
92. thrownewProtocolException("这不是HTTP协议");
93. this.target=target;
94. }catch(MalformedURLExceptionm){
95. thrownewProtocolException("协议格式错误");
96. }
97. }
98. /*
99. *与Web服务器连接。若找不到Web服务器，InetAddress会引发UnknownHostException
100. *异常。若Socket连接失败，会引发IOException异常。
101. */
102. protectedvoidopenServer(Stringhost,intport)throws
103. UnknownHostException,IOException{
104. header.clear();
105. responseMessage="";responseCode=-1;
106. try{
107. if(client!=null)closeServer();
108. if(byteStream!=null){
109. byteStream.close();byteStream=null;
110. }
111. InetAddressaddress=InetAddress.getByName(host);
112. client=newSocket(address,port==-1?80:port);
113. sender=newBufferedOutputStream(client.getOutputStream());
114. receiver=newBufferedInputStream(client.getInputStream());
115. }catch(UnknownHostExceptionu){
116. throwu;
117. }catch(IOExceptioni){
118. throwi;
119. }
120. }
121. /*关闭与Web服务器的连接*/
122. protectedvoidcloseServer()throwsIOException{
123. if(client==null)return;
124. try{
125. client.close();sender.close();receiver.close();
126. }catch(IOExceptioni){
127. throwi;
128. }
129. client=null;sender=null;receiver=null;
130. }
131. protectedStringgetURLFormat(URLtarget){
132. Stringspec="http://
133. +target.getHost();
134. if(target.getPort()!=-1)
135. spec+=":"+target.getPort();
136. returnspec+=target.getFile();
137. }
138. /*向Web服务器传送数据*/
139. protectedvoidsendMessage(Stringdata)throwsIOException{
140. sender.write(data.getBytes(),0,data.length());
141. sender.flush();
142. }
143. /*接收来自Web服务器的数据*/
144. protectedvoidreceiveMessage()throwsIOException{
145. bytedata[]=newbyte[1024];
146. intcount=0;
147. intword=-1;
148. //解析第一行
149. while((word=receiver.read())!=-1){
150. if(word=='\r'||word=='\n'){
151. word=receiver.read();
152. if(word=='\n')word=receiver.read();
153. break;
154. }
155. if(count==data.length)data=addCapacity(data);
156. data[count++]=(byte)word;
157. }
158. Stringmessage=newString(data,0,count);
159. intmark=message.indexOf(32);
160. serverVersion=message.substring(0,mark);
161. while(mark<message.length()&&message.charAt(mark+1)==32)mark++;
162. responseCode=Integer.parseInt(message.substring(mark+1,mark+=4));
163. responseMessage=message.substring(mark,message.length()).trim();
164. //应答状态码和处理请读者添加
165. switch(responseCode){
166. case400:
167. thrownewIOException("错误请求");
168. case404:
169. thrownewFileNotFoundException(getURLFormat(target));
170. case503:
171. thrownewIOException("服务器不可用");
172. }
173. if(word==-1)thrownewProtocolException("信息接收异常终止");
174. intsymbol=-1;
175. count=0;
176. //解析元信息
177. while(word!='\r'&&word!='\n'&&word>-1){
178. if(word=='\t')word=32;
179. if(count==data.length)data=addCapacity(data);
180. data[count++]=(byte)word;
181. parseLine:{
182. while((symbol=receiver.read())>-1){
183. switch(symbol){
184. case'\t':
185. symbol=32;break;
186. case'\r':
187. case'\n':
188. word=receiver.read();
189. if(symbol=='\r'&&word=='\n'){
190. word=receiver.read();
191. if(word=='\r')word=receiver.read();
192. }
193. if(word=='\r'||word=='\n'||word>32)breakparseLine;
194. symbol=32;break;
195. }
196. if(count==data.length)data=addCapacity(data);
197. data[count++]=(byte)symbol;
198. }
199. word=-1;
200. }
201. message=newString(data,0,count);
202. mark=message.indexOf(':');
203. Stringkey=null;
204. if(mark>0)key=message.substring(0,mark);
205. mark++;
206. while(mark<message.length()&&message.charAt(mark)<=32)mark++;
207. Stringvalue=message.substring(mark,message.length());
208. header.put(key,value);
209. count=0;
210. }
211. //获得正文数据
212. while((word=receiver.read())!=-1){
213. if(count==data.length)data=addCapacity(data);
214. data[count++]=(byte)word;
215. }
216. if(count>0)byteStream=newByteArrayInputStream(data,0,count);
217. data=null;
218. closeServer();
219. }
220. publicStringgetResponseMessage(){
221. returnresponseMessage;
222. }
223. publicintgetResponseCode(){
224. returnresponseCode;
225. }
226. publicStringgetServerVersion(){
227. returnserverVersion;
228. }
229. publicInputStreamgetInputStream(){
230. returnbyteStream;
231. }
232. publicsynchronizedStringgetHeaderKey(inti){
233. if(i>=header.size())returnnull;
234. Enumerationenum=header.propertyNames();
235. Stringkey=null;
236. for(intj=0;j<=i;j++)
237. key=(String)enum.nextElement();
238. returnkey;
239. }
240. publicsynchronizedStringgetHeaderValue(inti){
241. if(i>=header.size())returnnull;
242. returnheader.getProperty(getHeaderKey(i));
243. }
244. publicsynchronizedStringgetHeaderValue(Stringkey){
245. returnheader.getProperty(key);
246. }
247. protectedStringgetBaseHeads(){
248. Stringinf="User-Agent:myselfHttp/1.0\r\n"+
249. "Accept:www/source;text/html;image/gif;*/*\r\n";
250. returninf;
251. }
252. privatebyte[]addCapacity(byterece[]){
253. bytetemp[]=newbyte[rece.length+1024];
254. System.arraycopy(rece,0,temp,0,rece.length);
255. returntemp;
256. }
257. publicstaticvoidmain(String[]args){
258. Httphttp=newHttp();
259. //http.GET("http://192.168.1.5
260. );
261. inti;
262. for(i=0;i<50000;i++){
263. http.GET("http://www.model-dl.com/modelinfo.asp?modelid=101);
264. http.POST("http://www.model-dl.com/modelinfo.asp?modelid=101,"ratecontd=101&MM_insert=form1");
265. }
266. }
267. }

以上就是对Java Socket应答的相关介绍，希望大家有所发现。