package hudson.plugins.global_build_stats.model;
import java.security.SecureRandom;
import java.util.Collections;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Map;
import java.util.Random;
import java.util.Set;
public class ModelIdGenerator {
public static final ModelIdGenerator INSTANCE = new ModelIdGenerator();
private static final int KEY_DEPTH = 32;
// Don't put here special URL characters ! (%, ?, &, =, # etc..)
private static final char[] AVAILABLE_CHARS = new char[]{
'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm',
'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z',
'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M',
'N', 'O', 'P', 'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z',
'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '@', '$', '*', '!'
};
private Map<Class, Set<String>> registeredIds = Collections.synchronizedMap(new HashMap<Class, Set<String>>());
private ModelIdGenerator(){
}
public void registerIdForClass(Class clazz, String id){
if(!registeredIds.containsKey(clazz)){
// Set should be synchronized
registeredIds.put(clazz, Collections.synchronizedSet(new HashSet<String>()));
}
registeredIds.get(clazz).add(id);
}
public String generateIdForClass(Class clazz){
String id = null;
do{
StringBuilder b = new StringBuilder();
Random r = new SecureRandom();
for(int i=0; i<KEY_DEPTH; i++){
b.append(AVAILABLE_CHARS[r.nextInt(AVAILABLE_CHARS.length)]);
}
id = b.toString();
// Re-generating id if it already exists
}while(registeredIds.containsKey(clazz) && registeredIds.get(clazz).contains(id));
registerIdForClass(clazz, id);
return id;
}
}