1. apk端的代码

 //获取wifi mac　地址
public static String getMacAddr() {
    try {
        return loadFileAsString("/sys/class/net/wlan0/address")
                .toUpperCase().substring(0, 17);
    } catch (IOException e) {
        e.printStackTrace();
        return "";
    }
}
private static String loadFileAsString(String filePath)
        throws java.io.IOException {
    StringBuffer fileData = new StringBuffer(1000);
    BufferedReader reader = new BufferedReader(new FileReader(filePath));
    char[] buf = new char[1024];
    int numRead = 0;
    while ((numRead = reader.read(buf)) != -1) {
        String readData = String.valueOf(buf, 0, numRead);
        fileData.append(readData);
    }
    reader.close();
    return fileData.toString();
}
//end 获取wifi mac 地址

2. 系统端需要给权限

sepolicy/vendor/untrusted_app.te
+allow untrusted_app  sysfs_net:dir {search getattr};
+allow untrusted_app  sysfs:file {read write open getattr};