Java FileReader上的FileNotFoundException
我的应用程序需要选择一个.txt文档,打开它,然后逐行阅读。我可以获取文件路径,没有问题,但是FileReader不会打开文件,引发FileNotFoundException 我的代码:Java FileReader上的FileNotFoundException,java,android,filereader,Java,Android,Filereader,我的应用程序需要选择一个.txt文档,打开它,然后逐行阅读。我可以获取文件路径,没有问题,但是FileReader不会打开文件,引发FileNotFoundException 我的代码: @Override protected void onActivityResult(int requestCode, int resultCode, Intent data) { switch(requestCode) { case ACTIVITY_CHOOSE_FILE: {
@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,所以难怪什么也找不到
而是打开一个输入流并从该流中读取
InputStream is = getContentResolver().openInputStream(data.getData());
filePath=uri.getPath()代码>。这不是文件系统路径。无法使用。而且它没有“和/或”,或者“无法理解”。FileReader
引发异常。BufferedReader
在该点上甚至不存在。注意,当你构造它时,你会把它扔掉,所以当你解决这个问题时,你会得到一个NPE试图调用readLine()
。