# GlobalThrowableMapper.java

    /*
     * Copyright (c) 2017, WSO2 Inc. (http://www.wso2.org) All Rights Reserved.
     *
     * WSO2 Inc. 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.wso2.carbon.mdm.services.android.exception;

    import com.google.gson.JsonParseException;
    import org.apache.commons.logging.Log;
    import org.apache.commons.logging.LogFactory;
    import org.wso2.carbon.mdm.services.android.util.AndroidDeviceUtils;

    import javax.naming.AuthenticationException;
    import javax.validation.ConstraintViolationException;
    import javax.ws.rs.ClientErrorException;
    import javax.ws.rs.core.Response;
    import javax.ws.rs.ext.ExceptionMapper;

    /**
     * Handle the cxf level exceptions.
     */
    public class GlobalThrowableMapper implements ExceptionMapper {
        private static final Log log = LogFactory.getLog(GlobalThrowableMapper.class);

        private ErrorDTO e500 = new ErrorDTO();

        GlobalThrowableMapper() {
            e500.setCode((long) 500);
            e500.setMessage("Internal server error.");
            e500.setMoreInfo("");
            e500.setDescription("The server encountered an internal error. Please contact administrator.");

        }

        @Override
        public Response toResponse(Throwable e) {

            if (e instanceof JsonParseException) {
                String errorMessage = "Malformed request body.";
                if (log.isDebugEnabled()) {
                    log.debug(errorMessage, e);
                }
                return AndroidDeviceUtils.buildBadRequestException(errorMessage).getResponse();
            }
            if (e instanceof NotFoundException) {
                    return ((NotFoundException) e).getResponse();
            }
            if (e instanceof BadRequestException) {
                return ((BadRequestException) e).getResponse();
            }
            if (e instanceof UnexpectedServerErrorException) {
                if (log.isDebugEnabled()) {
                    log.debug("Unexpected server error", e);
                }
                return ((UnexpectedServerErrorException) e).getResponse();
            }
            if (e instanceof ConstraintViolationException) {
                if (log.isDebugEnabled()) {
                    log.debug("Constraint violation issue.", e);
                    return ((ParameterValidationException) e).getResponse();
                }
            }
            if (e instanceof IllegalArgumentException) {
                ErrorDTO errorDetail = new ErrorDTO();
                errorDetail.setCode((long) 400);
                errorDetail.setMoreInfo("");
                errorDetail.setMessage("");
                errorDetail.setDescription(e.getMessage());
                return Response
                        .status(Response.Status.BAD_REQUEST)
                        .entity(errorDetail)
                        .build();
            }
            if (e instanceof ClientErrorException) {
                if (log.isDebugEnabled()) {
                    log.debug("Client error", e);
                }
                return ((ClientErrorException) e).getResponse();
            }
            if (e instanceof AuthenticationException) {
                ErrorDTO errorDetail = new ErrorDTO();
                errorDetail.setCode((long) 401);
                errorDetail.setMoreInfo("");
                errorDetail.setMessage("");
                errorDetail.setDescription(e.getMessage());
                return Response
                        .status(Response.Status.UNAUTHORIZED)
                        .entity(errorDetail)
                        .build();
            }
            if (e instanceof ForbiddenException) {
                if (log.isDebugEnabled()) {
                    log.debug("Resource forbidden", e);
                }
                return ((ForbiddenException) e).getResponse();
            }
            //unknown exception log and return
                log.error("An Unknown exception has been captured by global exception mapper.", e);
            return Response.status(Response.Status.INTERNAL_SERVER_ERROR).header("Content-Type", "application/json")
                    .entity(e500).build();
        }
    }