Read from FileChannel with java nio
0
Can you show me a simple example to read from a file named example.txt and put all contents into a string in my java program using java NIO?
Following is what I'm using for the moment:
FileChannel inChannel = FileChannel.open(Paths.get(file),StandardOpenOption.READ);
CharBuffer buf=ByteBuffer.allocate(1024).asCharBuffer();
while(inChannel.read(buf)!=-1)
buf.flip();
while(buf.hasRemaining())
//append to a String
buf.clear();
java string io nio java-io
edited Nov 11 '18 at 15:45
Bsquare
3,63851434
asked Nov 11 '18 at 13:09
jamesjames
227
add a comment |
0
Can you show me a simple example to read from a file named example.txt and put all contents into a string in my java program using java NIO?
Following is what I'm using for the moment:
FileChannel inChannel = FileChannel.open(Paths.get(file),StandardOpenOption.READ);
CharBuffer buf=ByteBuffer.allocate(1024).asCharBuffer();
while(inChannel.read(buf)!=-1)
buf.flip();
while(buf.hasRemaining())
//append to a String
buf.clear();
java string io nio java-io
edited Nov 11 '18 at 15:45
Bsquare
3,63851434
asked Nov 11 '18 at 13:09
jamesjames
227
Is there a particular reason to use straight java-nio? Because being this a common operation, in most cases you better using a utility class.
– AR1
Nov 11 '18 at 13:32
it is just an exercise to understand how java nio works
– james
Nov 11 '18 at 14:01
add a comment |
0
0
0
Can you show me a simple example to read from a file named example.txt and put all contents into a string in my java program using java NIO?
Following is what I'm using for the moment:
FileChannel inChannel = FileChannel.open(Paths.get(file),StandardOpenOption.READ);
CharBuffer buf=ByteBuffer.allocate(1024).asCharBuffer();
while(inChannel.read(buf)!=-1)
buf.flip();
while(buf.hasRemaining())
//append to a String
buf.clear();
java string io nio java-io
edited Nov 11 '18 at 15:45
Bsquare
3,63851434
asked Nov 11 '18 at 13:09
jamesjames
227
Can you show me a simple example to read from a file named example.txt and put all contents into a string in my java program using java NIO?
Following is what I'm using for the moment:
FileChannel inChannel = FileChannel.open(Paths.get(file),StandardOpenOption.READ);
CharBuffer buf=ByteBuffer.allocate(1024).asCharBuffer();
while(inChannel.read(buf)!=-1)
buf.flip();
while(buf.hasRemaining())
//append to a String
buf.clear();
java string io nio java-io
java string io nio java-io
edited Nov 11 '18 at 15:45
Bsquare
3,63851434
asked Nov 11 '18 at 13:09
jamesjames
227
edited Nov 11 '18 at 15:45
Bsquare
3,63851434
asked Nov 11 '18 at 13:09
jamesjames
227
edited Nov 11 '18 at 15:45
Bsquare
3,63851434
edited Nov 11 '18 at 15:45
Bsquare
3,63851434
edited Nov 11 '18 at 15:45
Bsquare
3,63851434
3,63851434
asked Nov 11 '18 at 13:09
jamesjames
227
asked Nov 11 '18 at 13:09
jamesjames
227
asked Nov 11 '18 at 13:09
jamesjames
227
227
Is there a particular reason to use straight java-nio? Because being this a common operation, in most cases you better using a utility class.
– AR1
Nov 11 '18 at 13:32
it is just an exercise to understand how java nio works
– james
Nov 11 '18 at 14:01
add a comment |
Is there a particular reason to use straight java-nio? Because being this a common operation, in most cases you better using a utility class.
– AR1
Nov 11 '18 at 13:32
it is just an exercise to understand how java nio works
– james
Nov 11 '18 at 14:01
Is there a particular reason to use straight java-nio? Because being this a common operation, in most cases you better using a utility class.
– AR1
Nov 11 '18 at 13:32
Is there a particular reason to use straight java-nio? Because being this a common operation, in most cases you better using a utility class.
– AR1
Nov 11 '18 at 13:32
it is just an exercise to understand how java nio works
– james
Nov 11 '18 at 14:01
it is just an exercise to understand how java nio works
– james
Nov 11 '18 at 14:01
add a comment |
1 Answer
1
active
oldest
votes
0
Try this:
public static String readFile(File f, int bufSize)
ReadableByteChannel rbc = FileChannel.open(Paths.get(f),StandardOpenOption.READ);
char ca = new char[bufSize];
ByteBuffer bb = ByteBuffer.allocate(bufSize);
StringBuilder sb = new StringBuilder();
while(rbc.read(bb) > -1)
CharBuffer cb = bb.asCharBuffer();
cb.flip();
cb.get(ca);
sb.append(ca);
cb.clear();
return sb.toString();
You could do without the middle man buffer ca if writing char by char is acceptable performance wise. In which case you could simply sb.append(cb.get()).
answered Nov 11 '18 at 13:27
MeetTitanMeetTitan
2,5091618
accordind to eclipseThe method read(ByteBuffer) in the type ReadableByteChannel is not applicable for the arguments (CharBuffer)
– james
Nov 11 '18 at 14:33
@James check my edit
– MeetTitan
Nov 11 '18 at 16:19
add a comment |
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1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
0
Try this:
public static String readFile(File f, int bufSize)
ReadableByteChannel rbc = FileChannel.open(Paths.get(f),StandardOpenOption.READ);
char ca = new char[bufSize];
ByteBuffer bb = ByteBuffer.allocate(bufSize);
StringBuilder sb = new StringBuilder();
while(rbc.read(bb) > -1)
CharBuffer cb = bb.asCharBuffer();
cb.flip();
cb.get(ca);
sb.append(ca);
cb.clear();
return sb.toString();
You could do without the middle man buffer ca if writing char by char is acceptable performance wise. In which case you could simply sb.append(cb.get()).
answered Nov 11 '18 at 13:27
MeetTitanMeetTitan
2,5091618
accordind to eclipseThe method read(ByteBuffer) in the type ReadableByteChannel is not applicable for the arguments (CharBuffer)
– james
Nov 11 '18 at 14:33
@James check my edit
– MeetTitan
Nov 11 '18 at 16:19
add a comment |
0
Try this:
public static String readFile(File f, int bufSize)
ReadableByteChannel rbc = FileChannel.open(Paths.get(f),StandardOpenOption.READ);
char ca = new char[bufSize];
ByteBuffer bb = ByteBuffer.allocate(bufSize);
StringBuilder sb = new StringBuilder();
while(rbc.read(bb) > -1)
CharBuffer cb = bb.asCharBuffer();
cb.flip();
cb.get(ca);
sb.append(ca);
cb.clear();
return sb.toString();
You could do without the middle man buffer ca if writing char by char is acceptable performance wise. In which case you could simply sb.append(cb.get()).
answered Nov 11 '18 at 13:27
MeetTitanMeetTitan
2,5091618
accordind to eclipseThe method read(ByteBuffer) in the type ReadableByteChannel is not applicable for the arguments (CharBuffer)
– james
Nov 11 '18 at 14:33
@James check my edit
– MeetTitan
Nov 11 '18 at 16:19
add a comment |
0
0
0
Try this:
public static String readFile(File f, int bufSize)
ReadableByteChannel rbc = FileChannel.open(Paths.get(f),StandardOpenOption.READ);
char ca = new char[bufSize];
ByteBuffer bb = ByteBuffer.allocate(bufSize);
StringBuilder sb = new StringBuilder();
while(rbc.read(bb) > -1)
CharBuffer cb = bb.asCharBuffer();
cb.flip();
cb.get(ca);
sb.append(ca);
cb.clear();
return sb.toString();
You could do without the middle man buffer ca if writing char by char is acceptable performance wise. In which case you could simply sb.append(cb.get()).
answered Nov 11 '18 at 13:27
MeetTitanMeetTitan
2,5091618
Try this:
public static String readFile(File f, int bufSize)
ReadableByteChannel rbc = FileChannel.open(Paths.get(f),StandardOpenOption.READ);
char ca = new char[bufSize];
ByteBuffer bb = ByteBuffer.allocate(bufSize);
StringBuilder sb = new StringBuilder();
while(rbc.read(bb) > -1)
CharBuffer cb = bb.asCharBuffer();
cb.flip();
cb.get(ca);
sb.append(ca);
cb.clear();
return sb.toString();
You could do without the middle man buffer ca if writing char by char is acceptable performance wise. In which case you could simply sb.append(cb.get()).
answered Nov 11 '18 at 13:27
MeetTitanMeetTitan
2,5091618
edited Nov 11 '18 at 19:38
answered Nov 11 '18 at 13:27
MeetTitanMeetTitan
2,5091618
answered Nov 11 '18 at 13:27
MeetTitanMeetTitan
2,5091618
answered Nov 11 '18 at 13:27
MeetTitanMeetTitan
2,5091618
2,5091618
accordind to eclipseThe method read(ByteBuffer) in the type ReadableByteChannel is not applicable for the arguments (CharBuffer)
– james
Nov 11 '18 at 14:33
@James check my edit
– MeetTitan
Nov 11 '18 at 16:19
add a comment |
accordind to eclipseThe method read(ByteBuffer) in the type ReadableByteChannel is not applicable for the arguments (CharBuffer)
– james
Nov 11 '18 at 14:33
@James check my edit
– MeetTitan
Nov 11 '18 at 16:19
accordind to eclipse
The method read(ByteBuffer) in the type ReadableByteChannel is not applicable for the arguments (CharBuffer)– james
Nov 11 '18 at 14:33
accordind to eclipse
The method read(ByteBuffer) in the type ReadableByteChannel is not applicable for the arguments (CharBuffer)– james
Nov 11 '18 at 14:33
@James check my edit
– MeetTitan
Nov 11 '18 at 16:19
@James check my edit
– MeetTitan
Nov 11 '18 at 16:19
add a comment |
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Is there a particular reason to use straight java-nio? Because being this a common operation, in most cases you better using a utility class.
– AR1
Nov 11 '18 at 13:32
it is just an exercise to understand how java nio works
– james
Nov 11 '18 at 14:01