Class PushBuilder


  • public final class PushBuilder
    extends Object
    Build a request to be pushed. This is based on Servlet 4.0's PushBuilder. According section 8.2 of RFC 7540, a promised request must be cacheable and safe without a request body.

    A PushBuilder is obtained by calling Request.newPushBuilder(). Each call to this method will return a new instance of a PushBuilder based off the current HttpServletRequest. Any mutations to the returned PushBuilder are not reflected on future returns.

    The instance is initialized as follows:

    • The method is initialized to "GET"
    • The existing request headers of the current Request are added to the builder, except for:
      • Conditional headers (eg. If-Modified-Since)
      • Range headers
      • Expect headers
      • Authorization headers
      • Referrer headers
    • The Request.getRequestedSessionId() value, unless at the time of the call Request.getSession(boolean) has previously been called to create a new Session, in which case the new session ID will be used as the PushBuilder's requested session ID. The source of the requested session id will be the same as for the request
    • The Referer(sic) header will be set to Request.getRequestURL() plus any Request.getQueryString()
    • If Response.addCookie(Cookie) has been called on the associated response, then a corresponding Cookie header will be added to the PushBuilder, unless the Cookie.getMaxAge() is <=0, in which case the Cookie will be removed from the builder.

    The path method must be called on the PushBuilder instance before the call to push(). Failure to do so must cause an exception to be thrown from push(), as specified in that method.

    A PushBuilder can be customized by chained calls to mutator methods before the push() method is called to initiate an asynchronous push request with the current state of the builder. After the call to push(), the builder may be reused for another push, however the path and conditional headers are cleared before returning from push(). All other values are retained over calls to push().

    Since:
    2.3.30
    • Constructor Detail

      • PushBuilder

        public PushBuilder​(Request request)
    • Method Detail

      • method

        public PushBuilder method​(String method)

        Set the method to be used for the push.

        Parameters:
        method - the method to be used for the push.
        Returns:
        this builder.
        Throws:
        NullPointerException - if the argument is null
        IllegalArgumentException - if the argument is the empty String, or any non-cacheable or unsafe methods defined in RFC 7231, which are POST, PUT, DELETE, CONNECT, OPTIONS and TRACE.
      • queryString

        public PushBuilder queryString​(String queryString)
        Set the query string to be used for the push.

        Will be appended to any query String included in a call to path(String). Any duplicate parameters must be preserved. This method should be used instead of a query in path(String) when multiple push() calls are to be made with the same query string.

        Parameters:
        queryString - the query string to be used for the push.
        Returns:
        this builder.
      • sessionId

        public PushBuilder sessionId​(String sessionId)
        Set the SessionID to be used for the push. The session ID will be set in the same way it was on the associated request (ie as a cookie if the associated request used a cookie, or as a url parameter if the associated request used a url parameter). Defaults to the requested session ID or any newly assigned session id from a newly created session.
        Parameters:
        sessionId - the SessionID to be used for the push.
        Returns:
        this builder.
      • setHeader

        public PushBuilder setHeader​(String name,
                                     String value)

        Set a request header to be used for the push. If the builder has an existing header with the same name, its value is overwritten.

        Parameters:
        name - The header name to set
        value - The header value to set
        Returns:
        this builder.
      • setHeader

        public PushBuilder setHeader​(org.glassfish.grizzly.http.util.Header name,
                                     String value)

        Set a request header to be used for the push. If the builder has an existing header with the same name, its value is overwritten.

        Parameters:
        name - The Header to set
        value - The header value to set
        Returns:
        this builder.
      • addHeader

        public PushBuilder addHeader​(String name,
                                     String value)

        Add a request header to be used for the push.

        Parameters:
        name - The header name to add
        value - The header value to add
        Returns:
        this builder.
      • addHeader

        public PushBuilder addHeader​(org.glassfish.grizzly.http.util.Header name,
                                     String value)

        Add a request header to be used for the push.

        Parameters:
        name - The Header to add
        value - The header value to add
        Returns:
        this builder.
      • removeHeader

        public PushBuilder removeHeader​(String name)

        Remove the named request header. If the header does not exist, take no action.

        Parameters:
        name - The name of the header to remove
        Returns:
        this builder.
      • removeHeader

        public PushBuilder removeHeader​(org.glassfish.grizzly.http.util.Header name)

        Remove the named request header. If the header does not exist, take no action.

        Parameters:
        name - The Header to remove
        Returns:
        this builder.
      • path

        public PushBuilder path​(String path)
        Set the URI path to be used for the push. The path may start with "/" in which case it is treated as an absolute path, otherwise it is relative to the context path of the associated request. There is no path default and path(String) must be called before every call to push(). If a query string is present in the argument path, its contents must be merged with the contents previously passed to queryString, preserving duplicates.
        Parameters:
        path - the URI path to be used for the push, which may include a query string.
        Returns:
        this builder.
      • push

        public void push()
        Push a resource given the current state of the builder without blocking.

        Push a resource based on the current state of the PushBuilder. Calling this method does not guarantee the resource will actually be pushed, since it is possible the client can decline acceptance of the pushed resource using the underlying HTTP/2 protocol.

        Before returning from this method, the builder has its path set to null and all conditional headers removed. All other fields are left as is for possible reuse in another push.

        Throws:
        IllegalStateException - if there was no call to path on this instance either between its instantiation or the last call to push() that did not throw an IllegalStateException.
      • getMethod

        public String getMethod()
        Return the method to be used for the push.
        Returns:
        the method to be used for the push.
      • getQueryString

        public String getQueryString()
        Return the query string to be used for the push.
        Returns:
        the query string to be used for the push.
      • getSessionId

        public String getSessionId()
        Return the SessionID to be used for the push.
        Returns:
        the SessionID to be used for the push.
      • getHeaderNames

        public Iterable<String> getHeaderNames()
        Return the set of header to be used for the push.
        Returns:
        the set of header to be used for the push.
      • getHeader

        public String getHeader​(String name)
        Return the header of the given name to be used for the push.
        Returns:
        the header of the given name to be used for the push.
      • getPath

        public String getPath()
        Return the URI path to be used for the push.
        Returns:
        the URI path to be used for the push.