Java 中HttpURLConnection附件上传的实例详解
整合了一个自己写的采用Http做附件上传的工具，分享一下！
示例代码：
|
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
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
91
92
93
94
95
96
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
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
|
/**
* 以Http协议传输文件
*
* @author mingxue.zhang@163.com
*
*/
public class HttpPostUtil {
private final static char[] MULTIPART_CHARS = "-_1234567890abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ"
.toCharArray();
private URL url;
private HttpURLConnection conn;
private String boundary = null;
private Map<String, String> textParams = new HashMap<String, String>();
private Map<String, File> fileparams = new HashMap<String, File>();
public HttpPostUtil(String url) throws Exception {
this.url = new URL(url);
}
// 重新设置要请求的服务器地址，即上传文件的地址。
public void setUrl(String url) throws Exception {
this.url = new URL(url);
}
// 增加一个普通字符串数据到form表单数据中
public void addTextParameter(String name, String value) {
textParams.put(name, value);
}
// 增加一个文件到form表单数据中
public void addFileParameter(String name, File value) {
fileparams.put(name, value);
}
// 清空所有已添加的form表单数据
public void clearAllParameters() {
textParams.clear();
fileparams.clear();
}
/**
* 发送数据到服务器
*
* @return 一个字节包含服务器的返回结果的数组
* @throws Exception
*/
public byte[] send() throws Exception {
initConnection();
try {
conn.connect();
} catch (SocketTimeoutException e) {
throw new Exception(e);
}
OutputStream connOutStream = new DataOutputStream(
conn.getOutputStream());
writeFileParams(connOutStream);
writeStringParams(connOutStream);
writesEnd(connOutStream);
InputStream responseInStream = conn.getInputStream();
ByteArrayOutputStream responseOutStream = new ByteArrayOutputStream();
int len;
byte[] bufferByte = new byte[1024];
while ((len = responseInStream.read(bufferByte)) != -1) {
responseOutStream.write(bufferByte, 0, len);
}
responseInStream.close();
connOutStream.close();
conn.disconnect();
byte[] resultByte = responseOutStream.toByteArray();
responseOutStream.close();
return resultByte;
}
// 文件上传的connection的一些必须设置
private void initConnection() throws Exception {
StringBuffer buf = new StringBuffer("----");
Random rand = new Random();
for (int i = 0; i < 15; i++) {
buf.append(MULTIPART_CHARS[rand.nextInt(MULTIPART_CHARS.length)]);
}
this.boundary = buf.toString();
conn = (HttpURLConnection) this.url.openConnection();
conn.setDoOutput(true);
conn.setUseCaches(false);
conn.setConnectTimeout(3 * 60 * 1000); // 连接超时为10秒
conn.setRequestMethod("POST");
conn.setRequestProperty("Content-Type",
"multipart/form-data; boundary=" + boundary);
}
// 普通字符串数据
private void writeStringParams(OutputStream out) throws Exception {
Set<String> keySet = textParams.keySet();
for (Iterator<String> it = keySet.iterator(); it.hasNext();) {
String name = it.next();
String value = textParams.get(name);
out.write(("--" + boundary + "\r\n").getBytes());
out.write(("Content-Disposition: form-data; name=\"" + name + "\"\r\n")
.getBytes());
out.write(("\r\n").getBytes());
out.write((encode(value) + "\r\n").getBytes());
}
}
// 文件数据
private void writeFileParams(OutputStream out) throws Exception {
Set<String> keySet = fileparams.keySet();
for (Iterator<String> it = keySet.iterator(); it.hasNext();) {
String name = it.next();
File value = fileparams.get(name);
out.write(("--" + boundary + "\r\n").getBytes());
out.write(("Content-Disposition: form-data; name=\"" + name
+ "\"; filename=\"" + encode(value.getName()) + "\"\r\n")
.getBytes());
out.write(("Content-Type: " + getContentType(value) + "\r\n")
.getBytes());
out.write(("Content-Transfer-Encoding: " + "binary" + "\r\n")
.getBytes());
out.write(("\r\n").getBytes());
FileInputStream inStream = new FileInputStream(value);
int bytes = 0;
byte[] bufferByte = new byte[1024];
while ((bytes = inStream.read(bufferByte)) != -1) {
out.write(bufferByte, 0, bytes);
}
inStream.close();
out.write(("\r\n").getBytes());
}
}
// 添加结尾数据
private void writesEnd(OutputStream out) throws Exception {
out.write(("--" + boundary + "--" + "\r\n").getBytes());
out.write(("\r\n").getBytes());
}
// 获取文件的上传类型，图片格式为image/png,image/jpg等。非图片为application/octet-stream
private String getContentType(File f) throws Exception {
String fileName = f.getName();
if (fileName.endsWith(".jpg")) {
return "image/jpeg";
} else if (fileName.endsWith(".png")) {
return "image/png";
}
return "application/octet-stream";
}
// 对包含中文的字符串进行转码，此为UTF-8。服务器那边要进行一次解码
private String encode(String value) throws Exception {
return URLEncoder.encode(value, "UTF-8");
}
}
|
如有疑问请留言或者到本站社区交流讨论，感谢阅读，希望能帮助到大家，谢谢大家对本站的支持！
原文链接：http://zmx.iteye.com/blog/2211633