// 缓存实例的不可变类

package code;

class Name{

private static final int MAX_SIZE = 5;

private static int NUM;

private static Name[] cache = new Name[MAX_SIZE];

private final String name;

private Name(String name){

this.name = name;

};

public static Name createName(String name){

for(int i=0;i<NUM;i++){

if(Name.cache[i]!=null&&Name.cache[i].name.equals(name)){

return Name.cache[i];

}

}

if(NUM<MAX_SIZE){

Name name_ = new Name(name);

Name.cache[NUM++] = name_;

return name_;

}

else{

Name name_ = new Name(name);

cache[0] = name_;

return name_;

}

}

}

public class CacheImmutableTest{

public static void main(String[] args) {

Name a = Name.createName("a");

Name b = Name.createName("b");

Name c = Name.createName("c");

Name d = Name.createName("d");

Name e = Name.createName("e");

Name f = Name.createName("f");

Name g = Name.createName("a");

System.out.println(a==g);

Name h = Name.createName("b");

System.out.println(b==h);

Name i = Name.createName("c");

System.out.println(c==i);

}

}