将POJO转换为适用于GWT的地图

Question

The idea is to have a POJO like:

class MyBean {
  long id;
  int count;
  public void setCount(int count){
   this.count = count;
  }
}

Now, I need that the count be stored automatically as:

put("count", count);

or simply put, put("fieldname", fieldvalue);

Is there a library that can be used for this purpose that MyBean can exetnd to? I can easily do a copy constructor or something, however, the point here is automation and besides there are so many models in my app that will be having this Map stored POJO values...

Answer 1

You could create a simple PropertyMapGenerator using Apache Commons BeanUtils' PropertyUtils

public class PropertyMapGenerator {
    public static Map<String, Object> getPropertyMap(Object object) {
    HashMap<String, Object> propertyMap = new HashMap<>();

    // retrieve descriptors for all properties
    PropertyDescriptor[] descriptors = PropertyUtils.getPropertyDescriptors(object);

    for (PropertyDescriptor descriptor : descriptors) {
        // check if there is a reader method for this property i.e. if it can be accessed
        if (descriptor.getReadMethod() != null) {
            String name = descriptor.getName();
            try {
                propertyMap.put(name, PropertyUtils.getProperty(object, name));
            } catch (Exception e) {
                // handle this properly
                e.printStackTrace();
            }
        }
    }

    return propertyMap;
    }
}

Now you can simply pass your POJOs to this generator:

Map<String, Object> propertyMap = PropertyMapGenerator.getPropertyMap(myBean);