* @return the {@link ToolExperience} corresponding to the identifier.
* If there was no ToolExperience defined yet for this ID, a new one will
* be created and put into the map!
*/
public ToolExperience getToolExperience(String tool) {
ToolExperience b = toolExperience.get(tool);
if (b == null) {
b = new ToolExperience();
toolExperience.put(tool, b);
}
return b;
}