LongEncoder (JSimpleDB Utility Classes 2.1.7 API)

java.lang.Object
- org.jsimpledb.util.LongEncoder

```
public final class LongEncoder
extends Object
```
Encodes long values to/from binary, preserving sort order, and such that the length of the encoding is optimized for values near zero.
Encoded values are guaranteed to not start with 0x00 or 0xff.

Field Summary

Fields
Modifier and Type	Field and Description
`static int`	`MAX_ENCODED_LENGTH` Maximum possible length of an encoded value.
`static int`	`MAX_SINGLE_BYTE_ENCODED` Maximum value for the first byte of a single byte encoded value.
`static int`	`MAX_SINGLE_BYTE_VALUE` Maximum value that can be encoded as a single byte.
`static int`	`MIN_SINGLE_BYTE_ENCODED` Minimum value for the first byte of a single byte encoded value.
`static int`	`MIN_SINGLE_BYTE_VALUE` Minimum value that can be encoded as a single byte.
`static int`	`NEGATIVE_ADJUST` Adjustment applied to multi-byte encoded negative values before encoding.
`static int`	`POSITIVE_ADJUST` Adjustment applied to multi-byte encoded positive values before encoding.
`static int`	`ZERO_ADJUST` Adjustment applied to single byte encoded values before encoding.

Method Summary

Methods
Modifier and Type	Method and Description
`static long`	`decode(byte[] data)` Decode the given value.
`static int`	`decodeLength(int first)` Determine the length (in bytes) of an encoded value based on the first byte.
`static byte[]`	`encode(long value)` Encode the given value.
`static int`	`encodeLength(long value)` Determine the length (in bytes) of the encoded value.
`static void`	`main(String[] args)` Test routine.
`static long`	`read(ByteBuffer buf)` Read and decode a value from the given `ByteBuffer`.
`static long`	`read(ByteReader reader)` Read and decode a value from the input.
`static long`	`read(InputStream input)` Read and decode a value from the given `InputStream`.
`static void`	`skip(ByteReader reader)` Skip a value from the input.
`static void`	`write(ByteBuffer buf, long value)` Encode the given value and write it to the given `ByteBuffer`.
`static void`	`write(ByteWriter writer, long value)` Encode the given value to the output.
`static void`	`write(OutputStream out, long value)` Encode the given value and write it to the given `OutputStream`.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - MAX_ENCODED_LENGTH
```
public static final int MAX_ENCODED_LENGTH
```
    Maximum possible length of an encoded value.
    
    See Also:
    Constant Field Values
  - MIN_SINGLE_BYTE_ENCODED
```
public static final int MIN_SINGLE_BYTE_ENCODED
```
    Minimum value for the first byte of a single byte encoded value. Lower values indicate a multiple byte encoded negative value.
    
    See Also:
    Constant Field Values
  - MAX_SINGLE_BYTE_ENCODED
```
public static final int MAX_SINGLE_BYTE_ENCODED
```
    Maximum value for the first byte of a single byte encoded value. Higher values indicate a multiple byte encoded positive value.
    
    See Also:
    Constant Field Values
  - ZERO_ADJUST
```
public static final int ZERO_ADJUST
```
    Adjustment applied to single byte encoded values before encoding.
    
    See Also:
    Constant Field Values
  - MIN_SINGLE_BYTE_VALUE
```
public static final int MIN_SINGLE_BYTE_VALUE
```
    Minimum value that can be encoded as a single byte.
    
    See Also:
    Constant Field Values
  - MAX_SINGLE_BYTE_VALUE
```
public static final int MAX_SINGLE_BYTE_VALUE
```
    Maximum value that can be encoded as a single byte.
    
    See Also:
    Constant Field Values
  - NEGATIVE_ADJUST
```
public static final int NEGATIVE_ADJUST
```
    Adjustment applied to multi-byte encoded negative values before encoding.
    
    See Also:
    Constant Field Values
  - POSITIVE_ADJUST
```
public static final int POSITIVE_ADJUST
```
    Adjustment applied to multi-byte encoded positive values before encoding.
    
    See Also:
    Constant Field Values
- Method Detail
  - encode
```
public static byte[] encode(long value)
```
    Encode the given value.
    
    Parameters:
    value - value to encode
    
    Returns:
    encoded bytes
  - decode
```
public static long decode(byte[] data)
```
    Decode the given value.
    
    Parameters:
    data - encoded value
    
    Returns:
    decoded value
    
    Throws:
    
    IllegalArgumentException - if bytes contains an invalid encoding, or extra trailing garbage
  - write
```
public static void write(ByteWriter writer,
         long value)
```
    Encode the given value to the output.
    
    Parameters:
    writer - destination for the encoded value
    value - value to encode
    
    Throws:
    
    NullPointerException - if writer is null
  - write
```
public static void write(OutputStream out,
         long value)
                  throws IOException
```
    Encode the given value and write it to the given OutputStream.
    
    Parameters:
    out - destination for the encoded value
    value - value to encode
    
    Throws:
    
    IOException - if an I/O error occurs
    
    NullPointerException - if out is null
  - write
```
public static void write(ByteBuffer buf,
         long value)
```
    Encode the given value and write it to the given ByteBuffer.
    
    Parameters:
    buf - destination for the encoded value
    value - value to encode
    
    Throws:
    
    BufferOverflowException - if buf overflows
    
    ReadOnlyBufferException - if buf is read-only
    
    NullPointerException - if buf is null
  - read
```
public static long read(ByteReader reader)
```
    Read and decode a value from the input.
    
    Parameters:
    reader - input holding an encoded value
    
    Returns:
    the decoded value
    
    Throws:
    
    IllegalArgumentException - if an invalid encoding is encountered
    
    IllegalArgumentException - if the encoded value is truncated
    
    NullPointerException - if reader is null
  - read
```
public static long read(InputStream input)
                 throws IOException
```
    Read and decode a value from the given InputStream.
    
    Parameters:
    input - input source for the encoded value
    
    Returns:
    the decoded value
    
    Throws:
    
    IOException - if an I/O error occurs
    
    EOFException - if an unexpected EOF is encountered
    
    IllegalArgumentException - if an invalid encoding is encountered
    
    NullPointerException - if input is null
  - read
```
public static long read(ByteBuffer buf)
```
    Read and decode a value from the given ByteBuffer.
    
    Parameters:
    buf - input source for the encoded value
    
    Returns:
    the decoded value
    
    Throws:
    
    BufferUnderflowException - if buf underflows
    
    IllegalArgumentException - if an invalid encoding is encountered
    
    NullPointerException - if buf is null
  - skip
```
public static void skip(ByteReader reader)
```
    Skip a value from the input.
    
    Parameters:
    reader - input holding an encoded value
    
    Throws:
    
    IllegalArgumentException - if the first byte is 0xff
  - decodeLength
```
public static int decodeLength(int first)
```
    Determine the length (in bytes) of an encoded value based on the first byte.
    
    Parameters:
    first - first byte of encoded value (in lower eight bits; other bits are ignored)
    
    Returns:
    the length of the encoded value (including first)
    
    Throws:
    
    IllegalArgumentException - if the first byte is 0xff
  - encodeLength
```
public static int encodeLength(long value)
```
    Determine the length (in bytes) of the encoded value.
    
    Parameters:
    value - value to encode
    
    Returns:
    the length of the encoded value, a value between one and MAX_ENCODED_LENGTH
  - main
```
public static void main(String[] args)
```
    Test routine.
    
    Parameters:
    args - command line arguments

Class LongEncoder

Field Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

MAX_ENCODED_LENGTH

MIN_SINGLE_BYTE_ENCODED

MAX_SINGLE_BYTE_ENCODED

ZERO_ADJUST

MIN_SINGLE_BYTE_VALUE

MAX_SINGLE_BYTE_VALUE

NEGATIVE_ADJUST

POSITIVE_ADJUST

Method Detail

encode

decode

write

write

write

read

read

read

skip

decodeLength

encodeLength

main