FileReader 上的 FileNotFoundException
FileNotFoundException on FileReader
我的应用程序需要 select 一个 .txt 文档,打开它并逐行阅读。我可以毫无问题地获取文件路径,但 FileReader 无法打开文件,抛出 FileNotFoundException。
我的代码:
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
switch(requestCode) {
case ACTIVITY_CHOOSE_FILE: {
if (resultCode == RESULT_OK){
Uri uri = data.getData();
filePath = uri.getPath();
if (filePath != ""){
txtvFileSelected.setText(filePath);
try {
// FileReader reads text files in the default encoding.
FileReader fileReader = new FileReader(filePath);
// Always wrap FileReader in BufferedReader.
BufferedReader bufferedReader = null;
new BufferedReader(fileReader);
int currentLine = 0;
while((line = bufferedReader.readLine()) != null) {
System.out.println(line);
//TODO: add string separation into floats here.
currentLine++;
}
// Always close files.
bufferedReader.close();
}
catch(FileNotFoundException ex) {
System.out.println("File not found '" + filePath + "'");
} catch (IOException e) {
e.printStackTrace();
}
}
else
txtvFileSelected.setText("No file selected");
}
}
}
}
错误日志:
05-14 09:14:51.409 24212-24279/com.examens.gilian.robotapplication OpenGLRenderer: Initialized EGL, version 1.4
05-14 09:14:53.428 24212-24279/com.examens.gilian.robotapplication D/OpenGLRenderer: endAllActiveAnimators on 0xb8ad5368 (RippleDrawable) with handle 0xb8988670
05-14 09:14:59.046 24212-24212/com.examens.gilian.robotapplication I/System.out: File not found '/document/primary:media/Data.txt'
filePath = uri.getPath();
这不是一个文件系统路径,难怪找不到任何东西。
改为打开输入流并从流中读取。
InputStream is = getContentResolver().openInputStream(data.getData());
我的应用程序需要 select 一个 .txt 文档,打开它并逐行阅读。我可以毫无问题地获取文件路径,但 FileReader 无法打开文件,抛出 FileNotFoundException。
我的代码:
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
switch(requestCode) {
case ACTIVITY_CHOOSE_FILE: {
if (resultCode == RESULT_OK){
Uri uri = data.getData();
filePath = uri.getPath();
if (filePath != ""){
txtvFileSelected.setText(filePath);
try {
// FileReader reads text files in the default encoding.
FileReader fileReader = new FileReader(filePath);
// Always wrap FileReader in BufferedReader.
BufferedReader bufferedReader = null;
new BufferedReader(fileReader);
int currentLine = 0;
while((line = bufferedReader.readLine()) != null) {
System.out.println(line);
//TODO: add string separation into floats here.
currentLine++;
}
// Always close files.
bufferedReader.close();
}
catch(FileNotFoundException ex) {
System.out.println("File not found '" + filePath + "'");
} catch (IOException e) {
e.printStackTrace();
}
}
else
txtvFileSelected.setText("No file selected");
}
}
}
}
错误日志:
05-14 09:14:51.409 24212-24279/com.examens.gilian.robotapplication OpenGLRenderer: Initialized EGL, version 1.4
05-14 09:14:53.428 24212-24279/com.examens.gilian.robotapplication D/OpenGLRenderer: endAllActiveAnimators on 0xb8ad5368 (RippleDrawable) with handle 0xb8988670
05-14 09:14:59.046 24212-24212/com.examens.gilian.robotapplication I/System.out: File not found '/document/primary:media/Data.txt'
filePath = uri.getPath();
这不是一个文件系统路径,难怪找不到任何东西。
改为打开输入流并从流中读取。
InputStream is = getContentResolver().openInputStream(data.getData());