com.logsniffer.web.controller.exception.RestErrorHandler.java Source code

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Here is the source code for com.logsniffer.web.controller.exception.RestErrorHandler.java

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/*******************************************************************************
 * logsniffer, open source tool for viewing, monitoring and analysing log data.
 * Copyright (c) 2015 Scaleborn UG, www.scaleborn.com
 *
 * logsniffer is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * logsniffer is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *******************************************************************************/
package com.logsniffer.web.controller.exception;

import java.io.IOException;
import java.util.HashMap;
import java.util.List;
import java.util.Locale;
import java.util.Map;

import javax.servlet.http.HttpServletResponse;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.MessageSource;
import org.springframework.context.i18n.LocaleContextHolder;
import org.springframework.core.Ordered;
import org.springframework.core.annotation.Order;
import org.springframework.http.HttpStatus;
import org.springframework.http.converter.HttpMessageConversionException;
import org.springframework.validation.FieldError;
import org.springframework.web.bind.MethodArgumentNotValidException;
import org.springframework.web.bind.annotation.ControllerAdvice;
import org.springframework.web.bind.annotation.ExceptionHandler;
import org.springframework.web.bind.annotation.ResponseBody;
import org.springframework.web.bind.annotation.ResponseStatus;
import org.springframework.web.bind.annotation.RestController;

/**
 * Error handler for REST validation.
 * 
 * @author mbok
 * 
 */
@ControllerAdvice(annotations = RestController.class)
@Order(Ordered.HIGHEST_PRECEDENCE)
public class RestErrorHandler {
    static final String REST_SPECIFIC_ERROR_HANDLER = "restSpecificErrorHandler";

    private static final Logger LOGGER = LoggerFactory.getLogger(RestErrorHandler.class);

    @Autowired
    private MessageSource messageSource;

    @ControllerAdvice(annotations = RestController.class)
    @Order(Ordered.LOWEST_PRECEDENCE)
    public static class ThrowableRestErrorHandler {

        @ExceptionHandler(value = Throwable.class)
        @ResponseBody
        public ErrorResponse processAllExceptions(final Throwable ex, final HttpServletResponse response)
                throws IOException {
            return processExceptionResponse(ex, response, org.apache.http.HttpStatus.SC_INTERNAL_SERVER_ERROR);
        }
    }

    @ExceptionHandler(ResourceNotFoundException.class)
    public ErrorResponse handleResourceNotFound(final ResourceNotFoundException ex,
            final HttpServletResponse response) throws IOException {
        return processExceptionResponse(ex, response, org.apache.http.HttpStatus.SC_NOT_FOUND);
    }

    @ExceptionHandler(MethodArgumentNotValidException.class)
    @ResponseStatus(HttpStatus.BAD_REQUEST)
    @ResponseBody
    public ErrorResponse processValidationError(final MethodArgumentNotValidException ex,
            final HttpServletResponse response) throws IOException {
        return processFieldErrors(processExceptionResponse(ex, response, org.apache.http.HttpStatus.SC_BAD_REQUEST),
                ex.getBindingResult().getFieldErrors());
    }

    @ExceptionHandler(HttpMessageConversionException.class)
    @ResponseStatus(HttpStatus.BAD_REQUEST)
    @ResponseBody
    public ErrorResponse processHttpMessageConversionError(final HttpMessageConversionException ex,
            final HttpServletResponse response) throws IOException {
        return processExceptionResponse(ex, response, org.apache.http.HttpStatus.SC_BAD_REQUEST);
    }

    private static ErrorResponse processExceptionResponse(final Throwable ex, final HttpServletResponse response,
            final int status) throws IOException {
        LOGGER.info("Catched exception", ex);
        final ErrorResponse er = new ErrorResponse();
        er.setException(ex);
        response.setStatus(status, er.getExceptionMessage());
        return er;
    }

    private ErrorResponse processFieldErrors(final ErrorResponse er, final List<FieldError> fieldErrors) {
        final Map<String, String> errors = new HashMap<String, String>();
        for (final FieldError fieldError : fieldErrors) {
            final String localizedErrorMessage = resolveLocalizedErrorMessage(fieldError);
            errors.put(fieldError.getField(), localizedErrorMessage);
        }
        er.setBindErrors(errors);
        return er;
    }

    private String resolveLocalizedErrorMessage(final FieldError fieldError) {
        final Locale currentLocale = LocaleContextHolder.getLocale();
        final String localizedErrorMessage = messageSource.getMessage(fieldError, currentLocale);
        return localizedErrorMessage;
    }
}