Lexical Decimal

Description

This library provides an implementation of a lexicographical encoding/decoding of BigDecimals. This allows you to store BigDecimal values as byte arrays in a key value store, or other similar storage engines. The ordering of the encoded value matches the ordering of the BigDecimal values.

This uses the encoding described in the Decimal Infinite paper.

Fourny, Ghislain. (2015). decimalInfinite: All Decimals In Bits, No Loss, Same Order, Simple.

Usage

1. Add a maven dependency.

 <dependency>
   <groupId>com.ebay.data.encoding</groupId>
   <artifactId>lexical-decimal</artifactId>
   <version>1.0</version>
 </dependency>

2. Encode a value

    BigDecimal val = new BigDecimal("1234.5678");
    byte []encoded = BigDecimalEncoding.encode(val).toByteArray();

3. Decode a previously encoded value

    byte []encoded ...
    BigDecimal val = BigDecimalEncoding.decode(encoded);

4. Accessing the encoded value

Encoding returns an instance of the Bits class that represents the encoded value. As above it can generate a byte array. In addition it can also write the bits to an existing array or Stream.

    OutputStream os = getOutputStream();
    BigDecimal val = new BigDecimal("1234.5678");
    BigDecimalEncoding.encode(val).writeTo(os);

See Also

• decimalgamma-cpp Is a c++ implementation from the paper's Author.
• decimalInfinite a JSONiq implementation.

License

Copyright 2019 eBay Inc. Author/Developer: Simon Fell

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

https://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.