Package totalcross.io

Class BufferedStream

java.lang.Object

totalcross.io.Stream

totalcross.io.BufferedStream

All Implemented Interfaces:

java.io.Closeable, java.lang.AutoCloseable

public class BufferedStream
extends Stream

BufferedStream offers a faster way to read and write data from streams in a buffered manner. This is especially useful when reading or writing large amounts of data. It works like the CompressedByteArrayStream, however it does not compresses the data like that one. Here's a sample code:

   public void writeLargeFile(String path, byte[] largeData) throws IOException
   {
      File f = new File(path, File.CREATE_EMPTY);
      BufferedStream bs = new BufferedStream(f, BufferedStream.WRITE, 4096);
      bs.writeBytes(largeData, 0, largeData.length);
      bs.close(); // important!
      f.close();
   }
 

Since:

TotalCross 1.0

Field Summary

Fields

Modifier and Type	Field	Description
static int	READ	Used for opening this buffered stream for reading.
static int	WRITE	Used for opening this buffered stream for writing.

Fields inherited from class totalcross.io.Stream

skipBuffer

Constructor Summary

Constructors

Constructor	Description
BufferedStream(Stream stream, int mode)	Creates a new buffered stream given the underlying stream and the mode to use.
BufferedStream(Stream stream, int mode, int bufferSize)	Creates a new buffered stream given the underlying stream, the mode to use and the buffer size.

Method Summary

Modifier and Type	Method	Description
void	close()	This method closes this stream, flushing any pending WRITE data.
Stream	getStream()	Returns the Stream attached to this BufferedStream.
int	readBytes(byte[] buf, int start, int count)	Reads bytes from the stream.
java.lang.String	readLine()	Reads a line of text from this BufferedStream.
void	setStream(Stream f)	Changes the initial Stream to the attached one.
int	writeBytes(byte[] buf, int start, int count)	Writes bytes to the stream.

Methods inherited from class totalcross.io.Stream

asInputStream, asOutputStream, asStream, asStream, skipBytes, wrapInputStream, wrapInputStreamToStream, write, writeBytes, writeBytes, writeBytes

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

READ

public static final int READ

Used for opening this buffered stream for reading.

See Also:

Constant Field Values

WRITE

public static final int WRITE

Used for opening this buffered stream for writing.

See Also:

Constant Field Values

Constructor Detail

BufferedStream

public BufferedStream(Stream stream,
                      int mode)
               throws IllegalArgumentIOException

Creates a new buffered stream given the underlying stream and the mode to use. This constructor will use the default buffer size: 2048 bytes.

Parameters:

stream - The underlying stream.

mode - The mode to use - READ or WRITE.

Throws:

IllegalArgumentIOException - if the mode is invalid.

BufferedStream

public BufferedStream(Stream stream,
                      int mode,
                      int bufferSize)
               throws IllegalArgumentIOException,
                      java.lang.NullPointerException

Creates a new buffered stream given the underlying stream, the mode to use and the buffer size.

Parameters:

stream - The underlying stream.

mode - The mode to use - READ or WRITE.

bufferSize - The buffer size.

Throws:

IllegalArgumentIOException - if the mode is invalid or the bufferSize is not a positive number.

java.lang.NullPointerException - if stream is null.

Method Detail

readBytes

public final int readBytes(byte[] buf,
                           int start,
                           int count)
                    throws IllegalArgumentIOException,
                           IOException,
                           java.lang.NullPointerException

Description copied from class: Stream

Reads bytes from the stream. Returns the number of bytes actually read or -1 if the end of the stream was reached. (if applicable to the stream)

Specified by:

readBytes in class Stream

Parameters:

buf - the byte array to read data into

start - the start position in the array

count - the number of bytes to read

Throws:

IOException

IllegalArgumentIOException

java.lang.NullPointerException

writeBytes

public final int writeBytes(byte[] buf,
                            int start,
                            int count)
                     throws IllegalArgumentIOException,
                            IOException,
                            java.lang.NullPointerException

Description copied from class: Stream

Writes bytes to the stream. Returns the number of bytes actually written or throws an IOException if an error prevented the write operation from occurring.

Specified by:

writeBytes in class Stream

Parameters:

buf - the byte array to write data from

start - the start position in the byte array

count - the number of bytes to write

Returns:

the number of bytes actually written

Throws:

IOException

IllegalArgumentIOException

java.lang.NullPointerException

close

public final void close()
                 throws IOException

This method closes this stream, flushing any pending WRITE data. It does NOT close the underlying stream.

Specified by:

close in interface java.lang.AutoCloseable

Specified by:

close in interface java.io.Closeable

Throws:

IOException - If an I/O error occurs.

setStream

public void setStream(Stream f)
               throws IOException,
                      java.lang.NullPointerException

Changes the initial Stream to the attached one. Reusing a BufferedStream throught this method can preserve memory.

Throws:

IOException

java.lang.NullPointerException

Since:

TotalCross 1.23

getStream

public Stream getStream()

Returns the Stream attached to this BufferedStream.

Since:

TotalCross 1.23

readLine

public java.lang.String readLine()
                          throws IOException

Reads a line of text from this BufferedStream. Any char lower than space is considered a new line separator. This method correctly handles newlines with \\n or \\r\\n.

Note: this method is VERY slow since it reads a single character per time. Consider using LineReader instead.

Returns:

the read line or null if nothing was read.

Throws:

IOException

Since:

SuperWaba 5.61

See Also:

LineReader