com.opengamma.util.rest.ExceptionThrowingClientFilter.java Source code

Introduction

Here is the source code for com.opengamma.util.rest.ExceptionThrowingClientFilter.java

Source

/**
 * Copyright (C) 2009 - present by OpenGamma Inc. and the OpenGamma group of companies
 *
 * Please see distribution for license.
 */
package com.opengamma.util.rest;

import javax.ws.rs.core.MultivaluedMap;

import org.apache.commons.lang.StringUtils;

import com.opengamma.OpenGammaRuntimeException;
import com.sun.jersey.api.client.ClientHandlerException;
import com.sun.jersey.api.client.ClientRequest;
import com.sun.jersey.api.client.ClientResponse;
import com.sun.jersey.api.client.UniformInterfaceException;
import com.sun.jersey.api.client.filter.ClientFilter;

/**
 * A Jersey filter to convert returned status codes to exceptions.
 */
public class ExceptionThrowingClientFilter extends ClientFilter {

    /**
     * Header key for exception type.
     */
    public static final String EXCEPTION_TYPE = "X-OpenGamma-ExceptionType";
    /**
     * Header key for exception message.
     */
    public static final String EXCEPTION_MESSAGE = "X-OpenGamma-ExceptionMessage";
    /**
     * Header key for exception point.
     */
    public static final String EXCEPTION_POINT = "X-OpenGamma-ExceptionPoint";

    /**
     * Creates the filter.
     * Always create a new instance, never cache.
     */
    public ExceptionThrowingClientFilter() {
        super();
    }

    //-------------------------------------------------------------------------
    @Override
    public ClientResponse handle(final ClientRequest cr) throws ClientHandlerException {
        ClientResponse response = getNext().handle(cr);
        if (response.getStatus() < 300) {
            return response; // normal valid response
        }
        MultivaluedMap<String, String> headers = response.getHeaders();
        String exType = headers.getFirst(EXCEPTION_TYPE);
        String exMsg = headers.getFirst(EXCEPTION_MESSAGE);
        if (exMsg == null) {
            exMsg = headers.getFirst(EXCEPTION_POINT);
        }
        UniformInterfaceException uiex;
        if (response.getStatus() == 404) {
            uiex = new UniformInterfaceException404NotFound(response, true);
        } else if (response.getStatus() == 204) {
            uiex = new UniformInterfaceException204NoContent(response, true);
        } else {
            uiex = new UniformInterfaceException(response, true);
        }
        if (exType == null) {
            throw uiex; // standard UniformInterfaceException as we have nothing to add
        }
        RuntimeException exception;
        try {
            Class<? extends RuntimeException> cls = Thread.currentThread().getContextClassLoader().loadClass(exType)
                    .asSubclass(RuntimeException.class);
            exception = cls.getConstructor(String.class)
                    .newInstance("Server threw exception: " + StringUtils.defaultString(exMsg));
        } catch (Exception ex) {
            // unable to create transparently, so use standard exception
            exception = new OpenGammaRuntimeException(
                    "Server threw exception: " + exType + ": " + StringUtils.defaultString(exMsg));
        }
        exception.initCause(uiex);
        throw exception; // transparently throw exception as seen on the server
    }

}