让记忆可以纠错、过期并保持隔离

memories.compute(key, (k, old) -> {
    if (old != null && incoming.version() < old.version()) return old; // 旧事件不覆盖新状态。
    if (old != null && incoming.version() == old.version() && !incoming.equals(old))
        throw new IllegalStateException("version conflict");
    return incoming; // 撤回标记也保存为有版本的状态。
});
// 单键原子更新不等于跨键事务、跨进程一致性或派生缓存自动失效。

import java.util.*;
public class Main {
    record Key(String user,String field){} record Revision(Key key,long version){}
    record Event(String user,String field,long version,String value,long expires,boolean revoked,String source){}
    static Map<String,String> replay(List<Event> events,String user,long now){
        if(now<0||user==null)throw new IllegalArgumentException("query");Map<Key,Event> latest=new HashMap<>();Map<Revision,Event> revisions=new HashMap<>();
        for(Event e:events){
            if(e.user()==null||e.field()==null||e.version()<1||e.value()==null||e.expires()<0||e.source()==null||e.source().isBlank())throw new IllegalArgumentException("event");
            Key key=new Key(e.user(),e.field());Event old=latest.get(key);
            Event duplicate=revisions.putIfAbsent(new Revision(key,e.version()),e);
            if(duplicate!=null&&!duplicate.equals(e))throw new IllegalArgumentException("version conflict"); // 历史同版本冲突也不忽略。
            if(old==null||e.version()>old.version())latest.put(key,e); // 撤回也保留最大版本。
        }
        Map<String,String> out=new TreeMap<>();
        for(Event e:latest.values())if(e.user().equals(user)&&!e.revoked()&&(e.expires()==0||now<e.expires()))out.put(e.field(),e.value()); // 先选新版本，再过滤期限。
        return out;
    }
    static Event e(String u,long v,String value,long expiry,boolean revoked){return new Event(u,"style",v,value,expiry,revoked,"message:"+v);}
    static void eq(Object x,Object y){if(!x.equals(y))throw new AssertionError(y);}
    public static void main(String[] args){
        eq(Map.of("style","short"),replay(List.of(e("A",2,"short",0,false),e("A",1,"long",0,false)),"A",10));
        eq(Map.of(),replay(List.of(e("A",2,"",0,true),e("A",1,"long",0,false)),"A",10));
        eq(Map.of(),replay(List.of(e("A",1,"long",0,false),e("A",2,"short",5,false)),"A",5));
        eq(Map.of("style","short"),replay(List.of(e("A",1,"short",0,false),e("B",9,"long",0,false)),"A",0));
        Event x=e("A",1,"short",0,false);eq(Map.of("style","short"),replay(List.of(x,x),"A",0));
        try{replay(List.of(x,e("A",1,"long",0,false)),"A",0);throw new AssertionError();}catch(IllegalArgumentException expected){}
        System.out.println("PASS 6 tests");
    }
}