Characterization of objects of a computer program while running same

A computer readable medium including computer instructions executable on a computer for carrying out a method of characterizing objects generated during at least a partial run of a program, each object being characterized by a plurality of alternative properties which can be selected, said method comprising:

• a) instrumenting said at least partial run of said program to determine characterization information about each of said objects;
• b) determining a desirable property for each of said objects;
• c) determining a correlation between said desirable property and said characterization information for each of said objects;
• d) using said correlation to select an property for an object subsequently created during an at least partial run of said program based upon characterization information about the subsequently created object.