Android中发送Http请求实例（包括文件上传、servlet接收）

前天开始要准备实现手机端往服务器传参数，还要能传附件，找了不少文章和资料，现在总结一下分享分享：代码中的catch什么的就省略了，尝试了图片、txt、xml是没问题的.. 各位 尽情拍砖吧。

发完发现代码部分的格式……这个编辑器不太会用，怎么感觉把换行都去掉了,处理好换行缩进也……

首先我是写了个java工程测试发送post请求：可以包含文本参数和文件参数****************************************************

1 /**

2 * 通过http协议提交数据到服务端，实现表单提交功能，包括上传文件

3 * @param actionUrl 上传路径

4 * @param params 请求参数 key为参数名,value为参数值

5 * @param file 上传文件

6 */

7 public static void postMultiParams(String actionUrl, Map<String, String> params, FormBean[] files) {

8 try {

9 PostMethod post = new PostMethod(actionUrl);

10 List<art> formParams = new ArrayList<art>();

11 for(Map.Entry<String, String> entry : params.entrySet()){

12 formParams.add(new StringPart(entry.getKey(), entry.getValue()));

13 }

14

15 if(files!=null)

16 for(FormBean file : files){

17 //filename为在服务端接收时希望保存成的文件名，filepath是本地文件路径(包括了源文件名)，filebean中就包含了这俩属性

18 formParams.add(new FilePart("file", file.getFilename(), new File(file.getFilepath())));

19 }

20

21 Part[] parts = new Part[formParams.size()];

22 Iterator<art> pit = formParams.iterator();

23 int i=0;

24

25 while(pit.hasNext()){

26 parts[i++] = pit.next();

27 }

28 //如果出现乱码可以尝试一下方式

29 //StringPart sp = new StringPart("TEXT", "testValue", "GB2312");

30 //FilePart fp = new FilePart("file", "test.txt", new File("./temp/test.txt"), null, "GB2312"

31 //postMethod.getParams().setContentCharset("GB2312");

32

33 MultipartRequestEntity mrp = new MultipartRequestEntity(parts, post.getParams());

34 post.setRequestEntity(mrp);

35

36 //execute post method

37 HttpClient client = new HttpClient();

38 int code = client.executeMethod(post);

39 System.out.println(code);

40 } catch ...

41 }

复制代码

通过以上代码可以成功的模拟java客户端发送post请求，服务端也能接收并保存文件

java端测试的main方法：

42 public static void main(String[] args){

43 String actionUrl = "http://192.168.0.123:8080/WSserver/androidUploadServlet";

44 Map<String, String> strParams = new HashMap<String, String>();

45 strParams.put("paramOne", "valueOne");

46 strParams.put("paramTwo", "valueTwo");

47 FormBean[] files = new FormBean[]{new FormBean("dest1.xml", "F:/testpostsrc/main.xml")};

48 HttpTool.postMultiParams(actionUrl,strParams,files);

49 }

复制代码

本以为大功告成了，结果一移植到android工程中，编译是没有问题的。

但是运行时抛了异常 先是说找不到PostMethod类，org.apache.commons.httpclient.methods.PostMethod这个类绝对是有包含的；

还有个异常就是VerifyError。 开发中有几次碰到这个异常都束手无策，觉得是SDK不兼容还是怎么地，哪位知道可得跟我说说～～

于是看网上有直接分析http request的内容构建post请求的，也有找到带上传文件的，拿下来运行老是有些问题，便直接通过运行上面的java工程发送的post请求，在servlet中打印出请求内容，然后对照着拼接字符串和流终于给实现了！代码如下：

***********************************************************

50 /**

51 * 通过拼接的方式构造请求内容，实现参数传输以及文件传输

52 * @param actionUrl

53 * @param params

54 * @param files

55 * @return

56 * @throws IOException

57 */

58 public static String post(String actionUrl, Map<String, String> params,

59 Map<String, File> files) throws IOException {

60

61 String BOUNDARY = java.util.UUID.randomUUID().toString();

62 String PREFIX = "--" , LINEND = "\r\n";

63 String MULTIPART_FROM_DATA = "multipart/form-data";

64 String CHARSET = "UTF-8";

65

66 URL uri = new URL(actionUrl);

67 HttpURLConnection conn = (HttpURLConnection) uri.openConnection();

68 conn.setReadTimeout(5 * 1000); // 缓存的最长时间

69 conn.setDoInput(true);// 允许输入

70 conn.setDoOutput(true);// 允许输出

71 conn.setUseCaches(false); // 不允许使用缓存

72 conn.setRequestMethod("POST");

73 conn.setRequestProperty("connection", "keep-alive");

74 conn.setRequestProperty("Charsert", "UTF-8");

75 conn.setRequestProperty("Content-Type", MULTIPART_FROM_DATA + ";boundary=" + BOUNDARY);

76

77 // 首先组拼文本类型的参数

78 StringBuilder sb = new StringBuilder();

79 for (Map.Entry<String, String> entry : params.entrySet()) {

80 sb.append(PREFIX);

81 sb.append(BOUNDARY);

82 sb.append(LINEND);

83 sb.append("Content-Disposition: form-data; name=\"" + entry.getKey() + "\"" + LINEND);

84 sb.append("Content-Type: text/plain; charset=" + CHARSET+LINEND);

85 sb.append("Content-Transfer-Encoding: 8bit" + LINEND);

86 sb.append(LINEND);

87 sb.append(entry.getValue());

88 sb.append(LINEND);

89 }

90

91 DataOutputStream outStream = new DataOutputStream(conn.getOutputStream());

92 outStream.write(sb.toString().getBytes());

93 // 发送文件数据

94 if(files!=null)

95 for (Map.Entry<String, File> file: files.entrySet()) {

96 StringBuilder sb1 = new StringBuilder();

97 sb1.append(PREFIX);

98 sb1.append(BOUNDARY);

99 sb1.append(LINEND);

100 sb1.append("Content-Disposition: form-data; name=\"file\"; filename=\""+file.getKey()+"\""+LINEND);

101 sb1.append("Content-Type: application/octet-stream; charset="+CHARSET+LINEND);

102 sb1.append(LINEND);

103 outStream.write(sb1.toString().getBytes());

104

105 InputStream is = new FileInputStream(file.getValue());

106 byte[] buffer = new byte[1024];

107 int len = 0;

108 while ((len = is.read(buffer)) != -1) {

109 outStream.write(buffer, 0, len);

110 }

111

112 is.close();

113 outStream.write(LINEND.getBytes());

114 }

115

116 //请求结束标志

117 byte[] end_data = (PREFIX + BOUNDARY + PREFIX + LINEND).getBytes();

118 outStream.write(end_data);

119 outStream.flush();

120 // 得到响应码

121 int res = conn.getResponseCode();

122 if (res == 200) {

123 InputStream in = conn.getInputStream();

124 int ch;

125 StringBuilder sb2 = new StringBuilder();

126 while ((ch = in.read()) != -1) {

127 sb2.append((char) ch);

128 }

129 }

130 outStream.close();

131 conn.disconnect();

132 return in.toString();

133 }

复制代码

**********************

button响应中的代码：

**********************

134 public void onClick(View v){

135 String actionUrl = getApplicationContext().getString(R.string.wtsb_req_upload);

136 Map<String, String> params = new HashMap<String, String>();

137 params.put("strParamName", "strParamValue");

138 Map<String, File> files = new HashMap<String, File>();

139 files.put("tempAndroid.txt", new File("/sdcard/temp.txt"));

140 try {

141 HttpTool.postMultiParams(actionUrl, params, files);

142 } catch ...

复制代码

***************************

服务器端servlet代码：

***************************

143 public void doPost(HttpServletRequest request, HttpServletResponse response)

144 throws ServletException, IOException {

145

146 //print request.getInputStream to check request content

147 //HttpTool.printStreamContent(request.getInputStream());

148

149 RequestContext req = new ServletRequestContext(request);

150 if(FileUpload.isMultipartContent(req)){

151 DiskFileItemFactory factory = new DiskFileItemFactory();

152 ServletFileUpload fileUpload = new ServletFileUpload(factory);

153 fileUpload.setFileSizeMax(FILE_MAX_SIZE);

154

155 List items = new ArrayList();

156 try {

157 items = fileUpload.parseRequest(request);

158 } catch ...

159

160 Iterator it = items.iterator();

161 while(it.hasNext()){

162 FileItem fileItem = (FileItem)it.next();

163 if(fileItem.isFormField()){

164 System.out.println(fileItem.getFieldName()+" "+fileItem.getName()+" "+new String(fileItem.getString().getBytes("ISO-8859-1"),"GBK"));

165 } else {

166 System.out.println(fileItem.getFieldName()+" "+fileItem.getName()+" "+

167 fileItem.isInMemory()+" "+fileItem.getContentType()+" "+fileItem.getSize());

168 if(fileItem.getName()!=null && fileItem.getSize()!=0){

169 File fullFile = new File(fileItem.getName());

170 File newFile = new File(FILE_SAVE_PATH+fullFile.getName());

171 try {

172 fileItem.write(newFile);

173 } catch ...

174 } else {

175 System.out.println("no file choosen or empty file");

176 }

177 }

178 }

179 }

180 }

181

182 public void init() throws ServletException {

183 //读取在web.xml中配置的init-param

184 FILE_MAX_SIZE = Long.parseLong(this.getInitParameter("file_max_size"));//上传文件大小限制

185 FILE_SAVE_PATH = this.getInitParameter("file_save_path");//文件保存位置

186 }