OptionsMethodHandler.java

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 * to you under the Apache License, Version 2.0 (the
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package org.apache.wink.server.internal.handlers;

import java.util.Properties;
import java.util.Set;

import javax.servlet.http.HttpServletResponse;
import javax.ws.rs.core.Response;

import org.apache.wink.common.http.HttpHeadersEx;
import org.apache.wink.common.http.HttpMethodEx;
import org.apache.wink.common.http.HttpStatus;
import org.apache.wink.common.internal.utils.HeaderUtils;
import org.apache.wink.server.handlers.HandlersChain;
import org.apache.wink.server.handlers.MessageContext;
import org.apache.wink.server.handlers.RequestHandler;
import org.apache.wink.server.internal.registry.ResourceRegistry;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class OptionsMethodHandler implements RequestHandler {

    private static final Logger logger = LoggerFactory.getLogger(OptionsMethodHandler.class);

    public void handleRequest(MessageContext context, HandlersChain chain) throws Throwable {

        // first thing - proceed the chain
        chain.doChain(context);

        // check the search result.
        // if the request is OPTIONS and no method was found, generate the
        // response automatically
        SearchResult searchResult = context.getAttribute(SearchResult.class);
        if (searchResult.isError() && searchResult.getError().getResponse().getStatus() == HttpStatus.METHOD_NOT_ALLOWED
            .getCode()
            && context.getHttpMethod().equalsIgnoreCase(HttpMethodEx.OPTIONS)) {
            // get supported HTTP methods
            ResourceRegistry resourceRegistry = context.getAttribute(ResourceRegistry.class);
            Set<String> httpMethods = resourceRegistry.getOptions(searchResult.getResource());

            logger
                .trace("Invoking OPTIONS request handled by runtime with {} resource and {} HTTP methods", //$NON-NLS-1$
                       searchResult.getResource(),
                       httpMethods);
            if (httpMethods.size() > 0) {
                String allowHeader = HeaderUtils.buildOptionsHeader(httpMethods);
                // add 'Allow' header to the response
                context.getAttribute(HttpServletResponse.class).addHeader(HttpHeadersEx.ALLOW,
                                                                          allowHeader);
                // remove an error from the search result
                context.getAttribute(SearchResult.class).setError(null);
                // set result to no-content
                context.setResponseStatusCode(Response.Status.NO_CONTENT.getStatusCode());
                context.setResponseEntity(null);
            }
        }
    }

    public void init(Properties props) {
    }

}