public class ByteWiseFileAccessor extends Object
| Constructor and Description |
|---|
ByteWiseFileAccessor(File file,
long offset,
int length,
int records)
Constructs a
ByteWiseFileAccessor object
which maps a region of a data file into memory. |
ByteWiseFileAccessor(URL url,
long offset,
int length)
Constructor.
|
ByteWiseFileAccessor(URL url,
long offset,
int length,
int records)
Constructs a
ByteWiseFileAccessor object
which maps a region of a data file into memory. |
ByteWiseFileAccessor(URL url,
long offset,
int length,
int records,
boolean checkSize)
Constructs a
ByteWiseFileAccessor object
which maps a region of a data file into memory. |
| Modifier and Type | Method and Description |
|---|---|
boolean |
hasRemaining()
Checks to see if the buffer can still be read.
|
void |
mark()
Marks the buffer.
|
byte |
readByte()
Reads a byte from the buffer.
|
byte[] |
readRecordBytes(int recordNum,
int offset,
int length)
Reads
length bytes of data from a specified record at the given offset. |
void |
reset()
Resets the buffer.
|
public ByteWiseFileAccessor(File file, long offset, int length, int records) throws FileNotFoundException, IOException
ByteWiseFileAccessor object
which maps a region of a data file into memory.file - the data fileoffset - the offset within the data filelength - the record length in bytesrecords - the number of recordsFileNotFoundException - If file does not exist, is a directory
rather than a regular file, or for some other reason cannot be opened for readingIOException - If an I/O error occurspublic ByteWiseFileAccessor(URL url, long offset, int length, int records) throws FileNotFoundException, IOException
ByteWiseFileAccessor object
which maps a region of a data file into memory.url - the data fileoffset - the offset within the data filelength - the record length in bytesrecords - the number of recordsFileNotFoundException - If file does not exist, is a directory
rather than a regular file, or for some other reason cannot be opened for readingIOException - If an I/O error occurspublic ByteWiseFileAccessor(URL url, long offset, int length, int records, boolean checkSize) throws FileNotFoundException, IOException
ByteWiseFileAccessor object
which maps a region of a data file into memory.url - the data fileoffset - the offset within the data filelength - the record length in bytesrecords - the number of recordscheckSize - check that the size of the data file is equal to the
size of the table (length * records) + offset.FileNotFoundException - If file does not exist, is a directory
rather than a regular file, or for some other reason cannot be opened for readingIOException - If an I/O error occurspublic ByteWiseFileAccessor(URL url, long offset, int length) throws IOException
url - The data file.offset - The offset within the data file.IOException - If an I/O error occurs.public byte[] readRecordBytes(int recordNum,
int offset,
int length)
length bytes of data from a specified record at the given offset.recordNum - the record number to read bytes from (1-relative)offset - an offset within the recordlength - the number of bytes to read from the recordpublic byte readByte()
public void mark()
public void reset()
public boolean hasRemaining()
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