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
166
167
168
169
170
171
|
/*
* Copyright (C) 2008 The Android Open Source Project
*
* Licensed 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 com.android.server.location;
import android.content.Context;
import android.net.Proxy;
import android.net.http.AndroidHttpClient;
import android.util.Log;
import org.apache.http.HttpEntity;
import org.apache.http.HttpHost;
import org.apache.http.HttpResponse;
import org.apache.http.StatusLine;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.client.methods.HttpUriRequest;
import org.apache.http.conn.params.ConnRouteParams;
import java.io.DataInputStream;
import java.io.IOException;
import java.util.Properties;
import java.util.Random;
/**
* A class for downloading GPS XTRA data.
*
* {@hide}
*/
public class GpsXtraDownloader {
private static final String TAG = "GpsXtraDownloader";
static final boolean DEBUG = false;
private Context mContext;
private String[] mXtraServers;
// to load balance our server requests
private int mNextServerIndex;
GpsXtraDownloader(Context context, Properties properties) {
mContext = context;
// read XTRA servers from the Properties object
int count = 0;
String server1 = properties.getProperty("XTRA_SERVER_1");
String server2 = properties.getProperty("XTRA_SERVER_2");
String server3 = properties.getProperty("XTRA_SERVER_3");
if (server1 != null) count++;
if (server2 != null) count++;
if (server3 != null) count++;
if (count == 0) {
Log.e(TAG, "No XTRA servers were specified in the GPS configuration");
return;
} else {
mXtraServers = new String[count];
count = 0;
if (server1 != null) mXtraServers[count++] = server1;
if (server2 != null) mXtraServers[count++] = server2;
if (server3 != null) mXtraServers[count++] = server3;
// randomize first server
Random random = new Random();
mNextServerIndex = random.nextInt(count);
}
}
byte[] downloadXtraData() {
String proxyHost = Proxy.getHost(mContext);
int proxyPort = Proxy.getPort(mContext);
boolean useProxy = (proxyHost != null && proxyPort != -1);
byte[] result = null;
int startIndex = mNextServerIndex;
if (mXtraServers == null) {
return null;
}
// load balance our requests among the available servers
while (result == null) {
result = doDownload(mXtraServers[mNextServerIndex], useProxy, proxyHost, proxyPort);
// increment mNextServerIndex and wrap around if necessary
mNextServerIndex++;
if (mNextServerIndex == mXtraServers.length) {
mNextServerIndex = 0;
}
// break if we have tried all the servers
if (mNextServerIndex == startIndex) break;
}
return result;
}
protected static byte[] doDownload(String url, boolean isProxySet,
String proxyHost, int proxyPort) {
if (DEBUG) Log.d(TAG, "Downloading XTRA data from " + url);
AndroidHttpClient client = null;
try {
client = AndroidHttpClient.newInstance("Android");
HttpUriRequest req = new HttpGet(url);
if (isProxySet) {
HttpHost proxy = new HttpHost(proxyHost, proxyPort);
ConnRouteParams.setDefaultProxy(req.getParams(), proxy);
}
req.addHeader(
"Accept",
"*/*, application/vnd.wap.mms-message, application/vnd.wap.sic");
req.addHeader(
"x-wap-profile",
"http://www.openmobilealliance.org/tech/profiles/UAPROF/ccppschema-20021212#");
HttpResponse response = client.execute(req);
StatusLine status = response.getStatusLine();
if (status.getStatusCode() != 200) { // HTTP 200 is success.
if (DEBUG) Log.d(TAG, "HTTP error: " + status.getReasonPhrase());
return null;
}
HttpEntity entity = response.getEntity();
byte[] body = null;
if (entity != null) {
try {
if (entity.getContentLength() > 0) {
body = new byte[(int) entity.getContentLength()];
DataInputStream dis = new DataInputStream(entity.getContent());
try {
dis.readFully(body);
} finally {
try {
dis.close();
} catch (IOException e) {
Log.e(TAG, "Unexpected IOException.", e);
}
}
}
} finally {
if (entity != null) {
entity.consumeContent();
}
}
}
return body;
} catch (Exception e) {
if (DEBUG) Log.d(TAG, "error " + e);
} finally {
if (client != null) {
client.close();
}
}
return null;
}
}
|
