ExceptionFilter.java

/*
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 * obtain a copy of the License at
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package org.glassfish.admin.rest.adapter;

import java.io.IOException;
import javax.ws.rs.container.ContainerRequestContext;
import javax.ws.rs.container.ContainerResponseContext;
import javax.ws.rs.container.ContainerResponseFilter;
import javax.ws.rs.core.MediaType;
import javax.ws.rs.ext.Provider;
import org.glassfish.admin.rest.Constants;
import org.glassfish.admin.rest.composite.CompositeResource;
import org.glassfish.admin.rest.model.ResponseBody;
import org.glassfish.admin.rest.utils.Util;

/**
 * This filter reformats string entities from non-success responses
 * into arrays of message entities (when not using the REST legacy mode).
 *
 * @author tmoreau
 */
@Provider
public class ExceptionFilter implements ContainerResponseFilter {

    public ExceptionFilter() {
    }

    @Override
    public void filter(ContainerRequestContext reqCtx, ContainerResponseContext resCtx) throws IOException {
        if (!Constants.MEDIA_TYPE_JSON.equals(reqCtx.getHeaderString("Accept"))) {
            // Don't wrap if using legacy mode
            return;
        }

        int status = resCtx.getStatus();
        if ((status >= 200) && (status <= 299)) {
            // don't wrap success messages
            return;
        }

        Object entity = resCtx.getEntity();
        if (!(entity instanceof String)) {
            // don't wrap null and non-String entities
            return;
        }

        // Normally the cliend sends in an X-Skip-Resource-Links header
        // to say that resource links should not be returned, and the resource
        // looks for that header in the request and, if present, tells
        // the ResponseBody constructor to ignore resource links.
        // Since we never return links from this filter, instead of looking
        // for the header, we can just always tell the ResponseBody to ignore links.
        ResponseBody rb = new ResponseBody(false);
        String errorMsg = (String)entity;
        rb.addFailure(errorMsg);
        resCtx.setEntity(rb, resCtx.getEntityAnnotations(), Constants.MEDIA_TYPE_JSON_TYPE);
    }
}