Question

我有以下代码，它工作正常。我的问题是代码下面的天气是否是线程安全的。通过阅读Servlet Filter和Container * Filter概念，我很困惑。

如何使此过滤器成为线程安全的？

 @Provider
public class ResourceLoggingFilter implements ContainerRequestFilter,   ContainerResponseFilter {

@Context
private ResourceInfo resourceInfo;

@Context
private HttpServletRequest  servletRequest;

@Inject
private java.util.logging.Logger logger;

public void filter(ContainerRequestContext requestContext,  ContainerResponseContext responseContext) throws IOException {
    String stTime = (String) requestContext.getProperty("StartTime"); 
    logger.log(Level.INFO,"<== Leaving Resource Path: "+ requestContext.getUriInfo().getPath());
    logger.log(Level.INFO,"<== Leaving Resource Method: "+  resourceInfo.getResourceMethod().getName());
    logger.log(Level.INFO,"<== Leaving Resource class: "+ resourceInfo.getResourceClass().getCanonicalName());
    logger.log(Level.INFO,"<== Leaving Session id: "+ servletRequest.getSession().getId());
    if (null == stTime || stTime.length() == 0) {
        logger.log(Level.INFO,"start-time not captured or cleared");
        stTime = "0";
    }
    long startTime = Long.parseLong(stTime);
    long executionTime = System.nanoTime() - startTime;
    logger.log(Level.INFO,"Total execution time : "+executionTime+" nano seconds."  );

}

public void filter(ContainerRequestContext requestContext) throws IOException {
    requestContext.setProperty("StartTime", String.valueOf(System.nanoTime())); 
    logger.log(Level.INFO,"==> Entering Resource Path: "+ requestContext.getUriInfo().getPath());
    logger.log(Level.INFO,"==> Entering Resource Method: "+  resourceInfo.getResourceMethod().getName());
    logger.log(Level.INFO,"==> Entering Resource class: "+ resourceInfo.getResourceClass().getCanonicalName());
    logger.log(Level.INFO,"==> Entering Session id: "+ servletRequest.getSession().getId());

}

}

修改有private volatile String stTime;语句是好的，所以stTime可以是线程安全的吗？

Answer 1

它已经是线程安全的。 ResourceInfo和HttpServletRequest都是代理（使用线程本地），而java.util.Logger上的方法是线程安全的。

请参阅：

ContainerRequestFilter和ContainerResponseFilter线程是否安全？

1 个答案: