Convert InputStream to BufferedReader

Question

I'm trying to read a text file line by line using InputStream from the assets directory in Android.

I want to convert the InputStream to a BufferedReader to be able to use the readLine().

I have the following code:

InputStream is;
is = myContext.getAssets().open ("file.txt");
BufferedReader br = new BufferedReader (is);

The third line drops the following error:

Multiple markers at this line
The constructor BufferedReader (InputStream) is undefinded.

What I'm trying to do in C++ would be something like:

StreamReader file;
file = File.OpenText ("file.txt");

line = file.ReadLine();
line = file.ReadLine();
...

What am I doing wrong or how should I do that? Thanks!

score 308 · Accepted Answer · answered Mar 04 '11 at 23:00

308

BufferedReader can't wrap an InputStream directly. It wraps another Reader. In this case you'd want to do something like:

BufferedReader br = new BufferedReader(new InputStreamReader(is, "UTF-8"));

answered Mar 04 '11 at 23:00

ColinD

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Yes, wrapping an InputStream with an InputStreamReader, which is wrapped by a BufferedReader is a common "trick" to use the readLine() function. – Setup Sep 29 '14 at 11:09
18

I recommend: `BufferedReader br = new BufferedReader(new InputStreamReader(is, StandardCharsets.UTF_8));` added in Java 7 – brcolow Mar 19 '15 at 21:51
StandardCharsets don't work on API Level >19. @brcolow – Florida Aug 15 '15 at 21:21
2

I think you mean to say doesn't work unless API Level >= 19? – brcolow Aug 15 '15 at 22:23
@brcolow StandardCharsets was added in API level 19. He means <19. – somega Apr 18 '22 at 11:29

G_H · Answer 2 · 2011-03-04T23:13:02.910

A BufferedReader constructor takes a reader as argument, not an InputStream. You should first create a Reader from your stream, like so:

Reader reader = new InputStreamReader(is);
BufferedReader br = new BufferedReader(reader);

Preferrably, you also provide a Charset or character encoding name to the StreamReader constructor. Since a stream just provides bytes, converting these to text means the encoding must be known. If you don't specify it, the system default is assumed.

score 21 · Answer 3 · answered Mar 04 '11 at 23:02

21

InputStream is;
InputStreamReader r = new InputStreamReader(is);
BufferedReader br = new BufferedReader(r);

answered Mar 04 '11 at 23:02

Hans

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Convert InputStream to BufferedReader

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