org.oscim.tiling.source.mapfile

Class ReadBuffer

java.lang.Object

org.oscim.tiling.source.mapfile.ReadBuffer

public class ReadBuffer
extends java.lang.Object

Reads from a RandomAccessFile into a buffer and decodes the data.

Method Summary

Modifier and Type	Method and Description
int	getPositionAndSkip()
byte	readByte() Returns one signed byte from the read buffer.
float	readFloat() Converts four bytes from the read buffer to a float.
boolean	readFromFile(int length) Reads the given amount of bytes from the file into the read buffer and resets the internal buffer position.
int	readInt() Converts four bytes from the read buffer to a signed int.
long	readLong() Converts eight bytes from the read buffer to a signed long.
int	readShort() Converts two bytes from the read buffer to a signed int.
int	readSignedInt() Converts a variable amount of bytes from the read buffer to a signed int.
void	readSignedInt(int[] values, int length) Converts a variable amount of bytes from the read buffer to a signed int array.
int	readUnsignedInt() Converts a variable amount of bytes from the read buffer to an unsigned int.
java.lang.String	readUTF8EncodedString() Decodes a variable amount of bytes from the read buffer to a string.
java.lang.String	readUTF8EncodedString(int stringLength) Decodes the given amount of bytes from the read buffer to a string.
java.lang.String	readUTF8EncodedStringAt(int position) Decodes a variable amount of bytes from the read buffer to a string.

Methods inherited from class java.lang.Object

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

Method Detail

readByte

public byte readByte()

Returns one signed byte from the read buffer.

Returns:

the byte value.

readFloat

public float readFloat()

Converts four bytes from the read buffer to a float.

The byte order is big-endian.

Returns:

the float value.

readFromFile

public boolean readFromFile(int length)
                     throws java.io.IOException

Reads the given amount of bytes from the file into the read buffer and resets the internal buffer position. If the capacity of the read buffer is too small, a larger one is created automatically.

Parameters:

length - the amount of bytes to read from the file.

Returns:

true if the whole data was read successfully, false otherwise.

Throws:

java.io.IOException - if an error occurs while reading the file.

readInt

public int readInt()

Converts four bytes from the read buffer to a signed int.

The byte order is big-endian.

Returns:

the int value.

readLong

public long readLong()

Converts eight bytes from the read buffer to a signed long.

The byte order is big-endian.

Returns:

the long value.

readShort

public int readShort()

Converts two bytes from the read buffer to a signed int.

The byte order is big-endian.

Returns:

the int value.

readSignedInt

public int readSignedInt()

Converts a variable amount of bytes from the read buffer to a signed int.

The first bit is for continuation info, the other six (last byte) or seven (all other bytes) bits are for data. The second bit in the last byte indicates the sign of the number.

Returns:

the value.

readSignedInt

public void readSignedInt(int[] values,
                          int length)

Converts a variable amount of bytes from the read buffer to a signed int array.

The first bit is for continuation info, the other six (last byte) or seven (all other bytes) bits are for data. The second bit in the last byte indicates the sign of the number.

Parameters:

values - result values

length - number of values to read

readUnsignedInt

public int readUnsignedInt()

Converts a variable amount of bytes from the read buffer to an unsigned int.

The first bit is for continuation info, the other seven bits are for data.

Returns:

the int value.

readUTF8EncodedString

public java.lang.String readUTF8EncodedString()

Decodes a variable amount of bytes from the read buffer to a string.

Returns:

the UTF-8 decoded string (may be null).

getPositionAndSkip

public int getPositionAndSkip()

Returns:

...

readUTF8EncodedString

public java.lang.String readUTF8EncodedString(int stringLength)

Decodes the given amount of bytes from the read buffer to a string.

Parameters:

stringLength - the length of the string in bytes.

Returns:

the UTF-8 decoded string (may be null).

readUTF8EncodedStringAt

public java.lang.String readUTF8EncodedStringAt(int position)

Decodes a variable amount of bytes from the read buffer to a string.

Parameters:

position - buffer offset position of string

Returns:

the UTF-8 decoded string (may be null).