webhcat/svr/src/main/java/org/apache/hcatalog/templeton/SimpleWebException.java

/**
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.apache.hcatalog.templeton;

import java.io.IOException;
import java.util.Map;
import java.util.HashMap;
import javax.ws.rs.core.MediaType;
import javax.ws.rs.core.Response;

import org.codehaus.jackson.map.ObjectMapper;

/**
 * Simple exception that will return a json error payload if thrown
 * from a JAX web server.  We skip using WebApplicationException and
 * instead map our own so that Jersey doesn't log our exceptions as
 * error in the output log.  See SimpleExceptionMapper.
 */
public class SimpleWebException extends Throwable {
    public int httpCode;
    public Map<String, Object> params;

    public SimpleWebException(int httpCode, String msg) {
        super(msg);
        this.httpCode = httpCode;
    }

    public SimpleWebException(int httpCode, String msg, Map<String, Object> params) {
        super(msg);
        this.httpCode = httpCode;
        this.params = params;
    }

    public Response getResponse() {
        return buildMessage(httpCode, params, getMessage());
    }

    public static Response buildMessage(int httpCode, Map<String, Object> params,
                                        String msg) {
        HashMap<String, Object> err = new HashMap<String, Object>();
        err.put("error", msg);
        if (params != null)
            err.putAll(params);

        String json = "\"error\"";
        try {
            json = new ObjectMapper().writeValueAsString(err);
        } catch (IOException e) {
        }

        return Response.status(httpCode)
            .entity(json)
            .type(MediaType.APPLICATION_JSON)
            .build();
    }
}