通过使用Field对象设置原始数据类型

Question

Is there any way to set the value of a primitive through the use of fields? I've tried to play around with the following, but can't seem to get it to work.

temp[i].setInt(new Object(), new Integer(data[0]));

In this case temp would be an array of declared fields. The current index i holds a field that holds a primitive int value. Is this sort of thing even possible?

Answer 1

Assuming you have a Map of field names and values called fieldValues , and you want to set the values on an instance called myObject , this code would check the respective primitive type, then set its value appropriately.

for (String fieldName : fieldValues.keySet())
{
    Field field = myObject.getClass().getField(fieldName);

    if (field.getType().equals(Integer.TYPE))
    {
        field.setInt(myObject, Integer.parseInt(fieldValues.get(field.getName());
    }
    else if (field.getType().equals(Long.TYPE))
    {
        field.setLong(myObject, Long.parseLong(fieldValues.get(field.getName());
    }
    else if (field.getType().equals(Boolean.TYPE))
    {
        field.setBoolean(myObject, Boolean.parseBoolean(fieldValues.get(field.getName());
    }
    // more else branches for each needed primitive type
}