source: VirtualCollectionRegistry/trunk/VirtualCollectionRegistry/src/main/java/eu/clarin/cmdi/virtualcollectionregistry/rest/VirtualCollectionRegistryExceptionMapper.java @ 239

package eu.clarin.cmdi.virtualcollectionregistry.rest;

import java.util.ArrayList;
import java.util.List;

import javax.ws.rs.core.MediaType;
import javax.ws.rs.core.Response;
import javax.ws.rs.core.Response.Status;
import javax.ws.rs.ext.ExceptionMapper;
import javax.ws.rs.ext.Provider;
import javax.xml.stream.XMLStreamException;

import org.xml.sax.SAXParseException;

import eu.clarin.cmdi.virtualcollectionregistry.VirtualCollectionNotFoundException;
import eu.clarin.cmdi.virtualcollectionregistry.VirtualCollectionRegistryException;
import eu.clarin.cmdi.virtualcollectionregistry.VirtualCollectionRegistryPermissionException;
import eu.clarin.cmdi.virtualcollectionregistry.VirtualCollectionRegistryUsageException;

@Provider
public class VirtualCollectionRegistryExceptionMapper implements
                ExceptionMapper<VirtualCollectionRegistryException> {

        public Response toResponse(VirtualCollectionRegistryException e) {
                Status       status = null;
                List<String> errors = null;
                if (e instanceof VirtualCollectionRegistryUsageException) {
                        status = Status.BAD_REQUEST;
                        errors = getErrors(e.getCause());
                } else if (e instanceof VirtualCollectionRegistryPermissionException) {
                        status = Status.FORBIDDEN;
                } else if (e instanceof VirtualCollectionNotFoundException) {
                        status = Status.NOT_FOUND;
                } else {
                        if (hasCause(e.getCause(), XMLStreamException.class)) {
                                status = Status.BAD_REQUEST;
                        } else {
                                status = Status.INTERNAL_SERVER_ERROR;
                        }
                        errors = getErrors(e.getCause());
                }
                RestResponse response = new RestResponse();
                response.setIsSuccess(false);
                response.setInfo(e.getMessage());
                if (errors != null) {
                        response.setError(errors);
                }
                return Response
                                .status(status)
                                .type(MediaType.APPLICATION_XML)
                                .entity(response)
                                .build();
        }

        private static List<String> getErrors(Throwable t) {
                ArrayList<String> errors = new ArrayList<String>();
                while (t != null) {
                        if (t instanceof SAXParseException) {
                                final SAXParseException e = (SAXParseException) t;
                                String message = e.getMessage();
                                if (message.startsWith("cvc")) {
                                        int pos = message.indexOf(':');
                                        if (pos != 0) {
                                                message = message.substring(pos + 1);
                                        }
                                }
                                errors.add(message +
                           " [line = " + e.getLineNumber() +
                                                   ", column = " + e.getColumnNumber() + "]");
                        } else if (t instanceof XMLStreamException) {
                                final XMLStreamException e = (XMLStreamException) t;
                                String message = e.getMessage();
                                if (message.startsWith("ParseError")) {
                                        int pos = message.indexOf(':');
                                        if (pos != -1) {
                                                pos = message.indexOf(':', pos + 1);
                                                if (pos != -1) {
                                                        message = message.substring(pos + 1);
                                                }
                                        }
                                }
                                if (e.getLocation() != null) {
                                        message = message +
                                                " [line = " + e.getLocation().getLineNumber() +
                                                ", column = " + e.getLocation().getColumnNumber() +
                        "]";
                                }
                                errors.add(message); 
                        } else {
                                errors.add(t.getMessage());
                        }
                        t = t.getCause();
                };
                return errors;
        }

        private static boolean hasCause(Throwable t, Class<?> clazz) {
                while (t != null) {
                        if (clazz.isInstance(t)) {
                                return true;
                        }
                        t = t.getCause();
                }
                return false;
        }

} // class VirtualCollectionRegistryExceptionMapper