android，在文件中找一个String

private String getVersion(String key) {
if (new File("/etc/version.conf").exists()) {
try {
BufferedReader reader = new BufferedReader(new FileReader(
"/etc/version.conf"), 1024);
String a = "";
try {
while ((a = reader.readLine()) != null) {
if (a.indexOf(key) != -1) {// || a.indexOf(key2) != -1
return a.substring(a.indexOf(',') + 1, a.length());
}
}
} finally {
reader.close();
}
} catch (IOException e) {
Log.e("SDAC",
"IO Exception when getting kernel version for Device Info screen",
e);
}
}
return "";
}