Decoding/Encoding Structured Data with Android

https://github.com/benwicks/structured-data-demo

Transcript

1. http://github.com/benwicks/structured-data-demo Decoding/Encoding Structured Data with Android
2. Agenda • Discuss Decoding/Encoding • Explain Structured Data Formats • Look at Android Libraries • Interactive Demonstration
3. Decoding/Encoding Text file 01011011 00110101 01010100 00100100 01001010 01101101 01010101 00101011 01010101 01101101 01010101 00101011 01101101 01010101 ... Byte stream <?xml version=”1.0”?> <person> <name> Some guy </name> <birthday> 1990-01-01 </birthday> </person> Object Person - name : String - birthday : Date + getName() : String + isBirthday() : boolean Deserialization / Decoding 01011011 00110101 01010100 00100100 01001010 01101101 01010101 00101011 01010101 01101101 01010101 00101011 01101101 01010101 ... Byte stream Text file <?xml version=”1.0”?> <person> <name> Some guy </name> <birthday> 1990-01-01 </birthday> </person> Serialization / Encoding
4. Structured Data Formats • XML • JSON • Protocol Buffers
5. XML Pros • Human- and machine-readable • (somewhat) Self-describing Cons • Each key is duplicated for each entry
6. JSON Pros • Human- and machine-readable • (again, somewhat) Self-describing Cons • Each key is spelled out for each entry • Each key has associated delimiters ( “{“, “}”, “,”, “:”, “[“, “]”, “””)
7. Protocol Buffers Pros • Compact definition • Forward- and backward-compatible • Language- and platform-neutral Cons • Not human-readable
8. Protobuf message definition • Define the message once ◦ Use it on client and server side to define your data
9. Android-specific Libraries • XML ◦ Pull ◦ SAX • JSON ◦ Google’s gson ◦ FasterXML’s Jackson ◦ Square’s Moshi
10. XML: Pull / SAX • Pull Parser is recommended by Android docs • You write pretty verbose implementations to decode/encode • My implementations: ◦ PullParser ◦ XmlSaxParser
11. JSON: gson • Released June 2008 • Still actively developed (https://github.com/google/gson) • My implementation: ◦ GsonParser ◦ SpeciesWrapper ◦ Species ▪ @SerializedName annotations
12. JSON: Jackson • Released March 2008 • Still actively developed (https://github.com/FasterXML/jackson) • My implementation: ◦ JacksonHelper ◦ JacksonParser ◦ Species ▪ @JsonCreator and @JsonProperty annotations
13. JSON: Moshi • Released August 2014 • My implementation: ◦ MoshiParser ◦ SpeciesDateAdapter ◦ SpeciesWrapper ◦ Species ▪ @Json annotation
14. Protobuf: Wire • Released December 2012 (https://github.com/square/wire) • Generated file added 623 lines • According to square’s blog post, they reduced their method count by nearly 10k by switching their protobuf implementation to wire • My implementation: ◦ SpeciesList.proto and fine-tune my package structure ▪ Wire generated SpeciesList.java
15. Protobuf: Google’s Protoc • Released July 2008 (https://github.com/google/protobuf) • Generated file added 444 lines • My implementation: ◦ SpeciesList.proto and fine-tune my package structure ▪ protoc (with nano option) generated OuterGoogleSpeciesList.java ◦ ProtobufParser ◦ Species#fromGoogleSpecies and #toGoogleSpecies
16. Interactive Demonstration
20. Thank you