Package com.sleepycat.util

## Class PackedInteger

- java.lang.Object
- - com.sleepycat.util.PackedInteger

    public class PackedInteger
    extends java.lang.Object

Static methods for reading and writing packed integers.

Most applications should use the classes in the `com.sleepycat.bind.tuple` package rather than using this class directly.

See Also:
  Integer Formats

### Field Summary

Fields
`static int` `MAX_LENGTH` The maximum number of bytes needed to store an int value (5).
`static int` `MAX_LONG_LENGTH` The maximum number of bytes needed to store a long value (9).

### Constructor Summary

Constructors
`PackedInteger()`

### Method Summary

All Methods Static Methods Concrete Methods
`static int` `getReadIntLength​(byte[] buf, int off)` Returns the number of bytes that would be read by `readInt(byte[], int)`.
`static int` `getReadLongLength​(byte[] buf, int off)` Returns the number of bytes that would be read by `readLong(byte[], int)`.
`static int` `getReadSortedIntLength​(byte[] buf, int off)` Returns the number of bytes that would be read by `readSortedInt(byte[], int)`.
`static int` `getReadSortedLongLength​(byte[] buf, int off)` Returns the number of bytes that would be read by `readSortedLong(byte[], int)`.
`static int` `getWriteIntLength​(int value)` Returns the number of bytes that would be written by `writeInt(byte[], int, int)`.
`static int` `getWriteLongLength​(long value)` Returns the number of bytes that would be written by `writeLong(byte[], int, long)`.
`static int` `getWriteSortedIntLength​(int value)` Returns the number of bytes that would be written by `writeSortedInt(byte[], int, int)`.
`static int` `getWriteSortedLongLength​(long value)` Returns the number of bytes that would be written by `writeSortedLong(byte[], int, long)`.
`static int` `readInt​(byte[] buf, int off)` Reads a packed integer at the given buffer offset and returns it.
`static long` `readLong​(byte[] buf, int off)` Reads a packed long integer at the given buffer offset and returns it.
`static int` `readSortedInt​(byte[] buf, int off)` Reads a sorted packed integer at the given buffer offset and returns it.
`static long` `readSortedLong​(byte[] buf, int off)` Reads a sorted packed long integer at the given buffer offset and returns it.
`static int` `writeInt​(byte[] buf, int offset, int value)` Writes a packed integer starting at the given buffer offset and returns the next offset to be written.
`static int` `writeLong​(byte[] buf, int offset, long value)` Writes a packed long integer starting at the given buffer offset and returns the next offset to be written.
`static int` `writeSortedInt​(byte[] buf, int offset, int value)` Writes a packed sorted integer starting at the given buffer offset and returns the next offset to be written.
`static int` `writeSortedLong​(byte[] buf, int offset, long value)` Writes a packed sorted long integer starting at the given buffer offset and returns the next offset to be written.

### Methods inherited from class java.lang.Object

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

### Field Detail

#### MAX_LENGTH

    public static final int MAX_LENGTH

The maximum number of bytes needed to store an int value (5).

See Also:
  Constant Field Values

#### MAX_LONG_LENGTH

    public static final int MAX_LONG_LENGTH

The maximum number of bytes needed to store a long value (9).

See Also:
  Constant Field Values

### Constructor Detail

#### PackedInteger

    public PackedInteger()

### Method Detail

#### readInt

    public static int readInt​(byte[] buf,
                              int off)

Reads a packed integer at the given buffer offset and returns it.

Parameters:
  `buf` - the buffer to read from.
  `off` - the offset in the buffer at which to start reading.
Returns:
  the integer that was read.

#### readLong

    public static long readLong​(byte[] buf,
                                int off)

Reads a packed long integer at the given buffer offset and returns it.

Parameters:
  `buf` - the buffer to read from.
  `off` - the offset in the buffer at which to start reading.
Returns:
  the long integer that was read.

#### getReadIntLength

    public static int getReadIntLength​(byte[] buf,
                                       int off)

Returns the number of bytes that would be read by `readInt(byte[], int)`.

Because the length is stored in the first byte, this method may be called with only the first byte of the packed integer in the given buffer. This method only accesses one byte at the given offset.

Parameters:
  `buf` - the buffer to read from.
  `off` - the offset in the buffer at which to start reading.
Returns:
  the number of bytes that would be read.

#### getReadLongLength

    public static int getReadLongLength​(byte[] buf,
                                        int off)

Returns the number of bytes that would be read by `readLong(byte[], int)`.

Because the length is stored in the first byte, this method may be called with only the first byte of the packed integer in the given buffer. This method only accesses one byte at the given offset.

Parameters:
  `buf` - the buffer to read from.
  `off` - the offset in the buffer at which to start reading.
Returns:
  the number of bytes that would be read.

#### writeInt

    public static int writeInt​(byte[] buf,
                               int offset,
                               int value)

Writes a packed integer starting at the given buffer offset and returns the next offset to be written.

Parameters:
  `buf` - the buffer to write to.
  `offset` - the offset in the buffer at which to start writing.
  `value` - the integer to be written.
Returns:
  the offset past the bytes written.

#### writeLong

    public static int writeLong​(byte[] buf,
                                int offset,
                                long value)

Writes a packed long integer starting at the given buffer offset and returns the next offset to be written.

Parameters:
  `buf` - the buffer to write to.
  `offset` - the offset in the buffer at which to start writing.
  `value` - the long integer to be written.
Returns:
  the offset past the bytes written.

#### getWriteIntLength

    public static int getWriteIntLength​(int value)

Returns the number of bytes that would be written by `writeInt(byte[], int, int)`.

Parameters:
  `value` - the integer to be written.
Returns:
  the number of bytes that would be used to write the given integer.

#### getWriteLongLength

    public static int getWriteLongLength​(long value)

Returns the number of bytes that would be written by `writeLong(byte[], int, long)`.

Parameters:
  `value` - the long integer to be written.
Returns:
  the number of bytes that would be used to write the given long integer.

#### readSortedInt

    public static int readSortedInt​(byte[] buf,
                                    int off)

Reads a sorted packed integer at the given buffer offset and returns it.

Parameters:
  `buf` - the buffer to read from.
  `off` - the offset in the buffer at which to start reading.
Returns:
  the integer that was read.

#### readSortedLong

    public static long readSortedLong​(byte[] buf,
                                      int off)

Reads a sorted packed long integer at the given buffer offset and returns it.

Parameters:
  `buf` - the buffer to read from.
  `off` - the offset in the buffer at which to start reading.
Returns:
  the long integer that was read.

#### getReadSortedIntLength

    public static int getReadSortedIntLength​(byte[] buf,
                                             int off)

Returns the number of bytes that would be read by `readSortedInt(byte[], int)`.

Because the length is stored in the first byte, this method may be called with only the first byte of the packed integer in the given buffer. This method only accesses one byte at the given offset.

Parameters:
  `buf` - the buffer to read from.
  `off` - the offset in the buffer at which to start reading.
Returns:
  the number of bytes that would be read.

#### getReadSortedLongLength

    public static int getReadSortedLongLength​(byte[] buf,
                                              int off)

Returns the number of bytes that would be read by `readSortedLong(byte[], int)`.

Because the length is stored in the first byte, this method may be called with only the first byte of the packed integer in the given buffer. This method only accesses one byte at the given offset.

Parameters:
  `buf` - the buffer to read from.
  `off` - the offset in the buffer at which to start reading.
Returns:
  the number of bytes that would be read.

#### writeSortedInt

    public static int writeSortedInt​(byte[] buf,
                                     int offset,
                                     int value)

Writes a packed sorted integer starting at the given buffer offset and returns the next offset to be written.

Parameters:
  `buf` - the buffer to write to.
  `offset` - the offset in the buffer at which to start writing.
  `value` - the integer to be written.
Returns:
  the offset past the bytes written.

#### writeSortedLong

    public static int writeSortedLong​(byte[] buf,
                                      int offset,
                                      long value)

Writes a packed sorted long integer starting at the given buffer offset and returns the next offset to be written.

Parameters:
  `buf` - the buffer to write to.
  `offset` - the offset in the buffer at which to start writing.
  `value` - the long integer to be written.
Returns:
  the offset past the bytes written.

#### getWriteSortedIntLength

    public static int getWriteSortedIntLength​(int value)

Returns the number of bytes that would be written by `writeSortedInt(byte[], int, int)`.

Parameters:
  `value` - the integer to be written.
Returns:
  the number of bytes that would be used to write the given integer.

#### getWriteSortedLongLength

    public static int getWriteSortedLongLength​(long value)

Returns the number of bytes that would be written by `writeSortedLong(byte[], int, long)`.

Parameters:
  `value` - the long integer to be written.
Returns:
  the number of bytes that would be used to write the given long integer.