MessagePack/README.md

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Simple MessagePack
==================
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This is a simple Java library for handling MessagePack data. It doesn't do any object mapping, but maps to special
objects representing MessagePack types. To build, use command `./gradlew build`.
For most cases you might be better off using `org.msgpack:msgpack`, but I found that I needed something that generically
represents the internal structure of the data.
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_Simple MessagePack_ uses Semantic Versioning, meaning as long as the major version doesn't change, nothing should break if you
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update. Be aware though that this doesn't necessarily applies for SNAPSHOT builds and the development branch.
#### Master
[![Build Status](https://travis-ci.org/Dissem/MsgPack.svg?branch=master)](https://travis-ci.org/Dissem/MsgPack)
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#### Develop
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Limitations
--------------
* There is no fallback to BigInteger for large integer type numbers, so there might be an integer overflow when reading
too large numbers
* `MPFloat` uses the data type you're using to decide on precision (float 32 or 64) - not the actual value. E.g. 0.5
could be saved perfectly as a float 42, but if you provide a double value, it will be stored as float 64, wasting
4 bytes.
* If you want to use the 'ext format family', you'll need to implement and register your own `MPType` and
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`MPType.Unpacker`.
* Be aware that custom `MPType.Unpacker` take precedence over the default unpackers, i.e. if you accidentally define
your unpacker to handle strings, for example, you won't be able to unpack any regular strings anymore.
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Setup
-----
Add msgpack as Gradle dependency:
```Gradle
compile "ch.dissem.msgpack:msgpack:1.0.0"
```
Usage
-----
### Serialize Data
First, you'll need to create some msgpack objects to serialize:
```Java
MPMap<MPString, MPType<?>> object = new MPMap<>();
object.put(new MPString("compact"), new MPBoolean(true));
object.put(new MPString("schema"), new MPInteger(0));
```
or the shorthand version for simple types:
```Java
import static ch.dissem.msgpack.types.Utils.mp;
MPMap<MPString, MPType<?>> object = new MPMap<>();
object.put(mp("compact"), mp(true));
object.put(mp("schema"), mp(0));
```
then just use `pack(OutputStream)`:
```Java
OutputStream out = ...;
object.pack(out);
```
### Deserialize Data
For deserializing data there is the reader object:
```Java
Reader reader = Reader.getInstance()
```
just use `reader.read(InputStream)`. Unfortunately you'll need to make sure you got what you expected, the following
example might result in `ClassCastException` at weird places:
```Java
InputStream in = ...;
MPType read = reader.read(in);
MPMap<MPString, MPString> map = (MPMap<MPString, MPString>) read;
String value = map.get(mp("key")).getValue();
```