读取asset目录下面文件, 返回byte[] , fileName: key/hello.der
public byte[] readStream(String fileName) {
try{
InputStream inStream = getResources().getAssets().open(fileName);
ByteArrayOutputStream outStream = new ByteArrayOutputStream();
byte[] buffer = new byte[1024];
int len = -1;
while((len = inStream.read(buffer)) != -1){
outStream.write(buffer, 0, len);
}
outStream.close();
inStream.close();
return outStream.toByteArray();
} catch (Exception e) {
e.printStackTrace();
return null;
}
}
读取asset目录下面文件, 返回string
public String getFromAssets(String fileName) {
String content = null; //结果字符串
try {
InputStreamReader inputReader = new InputStreamReader(getResources().getAssets().open(fileName), "ISO_8859_1" );
BufferedReader bufReader = new BufferedReader(inputReader);
String line="";
StringBuilder builder = new StringBuilder();
while((line = bufReader.readLine()) != null){
builder.append(line);
}
inputReader.close();
bufReader.close();
return builder.toString();
} catch (Exception e) {
e.printStackTrace();
}
return content;
}
将文件保存到外部
writeFile(key.getBytes(StandardCharsets.ISO_8859_1), "demo/", "hello" + ".der");
public static boolean writeFile(byte[] buffer, String folder,
String fileName) {
boolean writeSucc = false;
boolean sdCardExist = Environment.getExternalStorageState().equals(
Environment.MEDIA_MOUNTED);
String folderPath = "";
if (sdCardExist) {
folderPath = Environment.getExternalStorageDirectory()
+ File.separator + folder + File.separator;
} else {
writeSucc = false;
}
File fileDir = new File(folderPath);
if (!fileDir.exists()) {
fileDir.mkdirs();
}
File file = new File(folderPath + fileName);
FileOutputStream out = null;
try {
out = new FileOutputStream(file, true);
out.write(buffer);
writeSucc = true;
} catch (Exception e) {
e.printStackTrace();
} finally {
try {
out.close();
} catch (Exception e) {
e.printStackTrace();
}
}
return writeSucc;
}
