sessionContext example

how to manage sessionContext data, need to be deeply looked inside.

import com.google.common.collect.Maps;
import com.tqmall.tqmallstall.model.UserAddress;
import com.tqmall.tqmallstall.model.Users;
import lombok.extern.slf4j.Slf4j;
import org.springframework.stereotype.Component;
import org.springframework.util.CollectionUtils;

import java.util.Map;

/**
 * <p> 业务上下文。session可以放在这里
 * <b>重要：所有的init必须跟着一个resetContext</b>
 */
@Slf4j
@Component
public class ContextHolder {
// ------------------------------ FIELDS ------------------------------

    /**
     * key为threadId
     */
    private Map<Long, SessionContext> sessionContextMap = Maps.newConcurrentMap();


// --------------------- GETTER / SETTER METHODS ---------------------

    public SessionContext getSessionContext() {
        final SessionContext sessionContext = sessionContextMap.get(currentThreadId());
        if (sessionContext == null) {
            throw new IllegalStateException("session context not properly initialized " +
                    "or initSessionContext method doesn't has been invoked!.");
        }
        return sessionContext;
    }


    void initSessionContext(final Users user, final UserAddress address,
                            Integer cityId, final Integer warehouseId,
                            Integer accountId) {
        if (isSessionContextInitialized()) {
            throw new IllegalStateException("duplicated initialization of sessionContext,check if this method invoked somewhere!!");
        }
        if (log.isDebugEnabled()) {
            log.debug("init session context, threadId:" + Thread.currentThread().getId());
        }
        sessionContextMap.put(currentThreadId(), new SessionContext(user,
                address, cityId, warehouseId, accountId));
    }

    private long currentThreadId() {
        return Thread.currentThread().getId();
    }

    private boolean isSessionContextInitialized() {
        return sessionContextMap.get(currentThreadId()) != null;
    }

    public void resetContext() {
        if (log.isDebugEnabled()) {
            log.debug("reset contextHolder, thread:"
                    + Thread.currentThread().getId());
        }
        try {
            sessionContextMap.remove(currentThreadId());
        } catch (Throwable ignored) {
        }
    }

    public void removeContext() {
        if (log.isDebugEnabled()) {
            log.debug("removeContext contextHolder, thread:" + Thread.currentThread().getId());
        }
        try {
            if (!CollectionUtils.isEmpty(sessionContextMap)) {
                sessionContextMap.clear();
            }
        } catch (Throwable ignored) {
        }
    }
}