# Miscellaneous

### Convert bean to map

Sometimes you may want to convert an object into a map, using the `JsonSerializer` exclude/include rules. This can be done with `BeanSerializer`, in few steps like this:

```java
final Map<String, Object> map = new HashMap<String, Object>();

JsonContext jsonContext = new JsonSerializer().createJsonContext(null);

BeanSerializer beanSerializer = new BeanSerializer(jsonContext, bean) {
    @Override
    protected void onSerializableProperty(
            String propertyName, Class propertyType, Object value) {
        map.put(propertyName, value);
    }
};

beanSerializer.serialize();
```

`BeanSerializer` parse beans and match properties to all include/exclude rules. Resulting map will contain all *included* properties of a bean. Serializing this map or the bean should give exactly the same results!

This may be handy if you have some further filtering options on some bean.

### Use JsonWriter

`JsonWriter` is a simple class that writes JSON to the output. You can use it to construct JSON directly, without serialization:

```java
StringBuilder sb = new StringBuilder();
JsonWriter jsonWriter = new JsonWriter(sb);

jsonWriter.writeOpenObject();
jsonWriter.writeName("one");
jsonWriter.writeNumber(Long.valueOf(123));
jsonWriter.writeComma();
jsonWriter.writeName("two");
jsonWriter.writeString("UberLight");
jsonWriter.writeCloseObject();
```

This can be handy when e.g. you need to wrap your serialized JSON into another simple map. Instead of creating a new `Map` object you can simply use the writer with the JSON result to create the same thing, but faster.


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