javadapters

Adapter framework for converting between different Java types

Usage

javadapters can be useful for converting between two different types, especially if the type being converted to is not explicitly known at runtime. A good example of this is parsing some set of arbitrary data from an external source and marshaling it into some known type using reflection.

...
private Map methodMap = new HashMap();
static {
  methodMap.put("foo", SomeType.class.getMethod("setFoo", Integer.class));
  methodMap.put("bar", SomeType.class.getMethod("setBar", Boolean.class));
  methodMap.put("baz", SomeType.class.getMethod("setBaz", MyCoolType.class));
}

public SomeType parseData(Map dataMap) {
  //Assume dataMap is a mapping from "foo"/"bar"/"baz" to 
  //the string representation of the data to set for that field
  SomeType st = new SomeType();
  for(Entry entry : dataMap.entrySet()) {
    Method m = methodMap.get(entry.getKey());
    Class parmType = m.getParameterTypes()[0];  
    Adapter adapter = AdapterFactory.getAdapter(String.class, parmType);
    
    //Invokes the correct setter method and convert the string parm
    //into the appropriate type for that method
    m.invoke(st, adapter.convert(entry.getValue(), parmType));
  }
}

In addition you can add your own adapter types using:

AdapterFactory.addAdapter(String.class, SpecialClass.class, 
  new SpecialClassAdapter());