org.focusns.common.web.widget.mvc.method.WidgetMethodArgumentResolver.java Source code

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Here is the source code for org.focusns.common.web.widget.mvc.method.WidgetMethodArgumentResolver.java

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package org.focusns.common.web.widget.mvc.method;

/*
 * #%L
 * FocusSNS Runtime
 * %%
 * Copyright (C) 2011 - 2013 FocusSNS
 * %%
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as
 * published by the Free Software Foundation, either version 2.1 of the
 * License, or (at your option) any later version.
 *
 * This program 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 Lesser Public License for more details.
 *
 * You should have received a copy of the GNU General Lesser Public
 * License along with this program.  If not, see
 * <http://www.gnu.org/licenses/lgpl-2.1.html>.
 * #L%
 */

import org.focusns.common.web.page.config.WidgetConfig;
import org.focusns.common.web.widget.annotation.bind.WidgetAttribute;
import org.focusns.common.web.widget.annotation.bind.WidgetPref;
import org.springframework.core.MethodParameter;
import org.springframework.core.convert.ConversionService;
import org.springframework.core.convert.ConverterNotFoundException;
import org.springframework.core.convert.TypeDescriptor;
import org.springframework.util.Assert;
import org.springframework.util.StringUtils;
import org.springframework.web.bind.support.WebDataBinderFactory;
import org.springframework.web.context.request.NativeWebRequest;
import org.springframework.web.context.request.WebRequest;
import org.springframework.web.method.support.HandlerMethodArgumentResolver;
import org.springframework.web.method.support.ModelAndViewContainer;

public class WidgetMethodArgumentResolver implements HandlerMethodArgumentResolver {

    public boolean supportsParameter(MethodParameter parameter) {
        //
        if (parameter.hasParameterAnnotation(WidgetAttribute.class)) {
            return true;
        } else if (parameter.hasParameterAnnotation(WidgetPref.class)) {
            return true;
        }
        //
        return false;
    }

    public Object resolveArgument(MethodParameter parameter, ModelAndViewContainer mavContainer,
            NativeWebRequest webRequest, WebDataBinderFactory binderFactory) throws Exception {
        //
        Object value = null;
        if (parameter.hasParameterAnnotation(WidgetAttribute.class)) {
            value = getWidgetAttributeValue(parameter, webRequest);
        } else if (parameter.hasParameterAnnotation(WidgetPref.class)) {
            value = getWidgetPrefValue(parameter, webRequest);
        }
        //
        if (value != null) {
            ConversionService conversionService = (ConversionService) webRequest
                    .getAttribute(ConversionService.class.getName(), WebRequest.SCOPE_REQUEST);
            if (conversionService.canConvert(value.getClass(), parameter.getParameterType())) {
                value = conversionService.convert(value, parameter.getParameterType());
            } else {
                throw new ConverterNotFoundException(TypeDescriptor.forObject(value),
                        TypeDescriptor.valueOf(parameter.getParameterType()));
            }
        }
        //
        return value;
    }

    private String getWidgetAttributeName(MethodParameter methodParameter, WidgetAttribute widgetAttribute) {
        String widgetAttributeName = methodParameter.getParameterName();
        if (StringUtils.hasText(widgetAttribute.value())) {
            widgetAttributeName = widgetAttribute.value();
        }
        //
        return widgetAttributeName;
    }

    private Object getWidgetAttributeValue(MethodParameter parameter, NativeWebRequest webRequest) {
        Class<?> widgetClass = parameter.getMethod().getDeclaringClass();
        WidgetAttribute widgetAttribute = parameter.getParameterAnnotation(WidgetAttribute.class);
        if (widgetAttribute != null) {
            String widgetAttributeName = getWidgetAttributeName(parameter, widgetAttribute);
            Object value = webRequest.getAttribute(widgetAttributeName, WebRequest.SCOPE_REQUEST);
            if (widgetAttribute.required()) {
                Assert.notNull(value,
                        String.format("%s attribute %s can not be null!", widgetClass, widgetAttributeName));
            }
            return value;
        }
        //
        return null;
    }

    private Object getWidgetPrefValue(MethodParameter methodParameter, NativeWebRequest webRequest) {
        WidgetPref widgetPreference = methodParameter.getParameterAnnotation(WidgetPref.class);
        if (widgetPreference != null) {
            WidgetConfig widgetConfig = (WidgetConfig) webRequest.getAttribute("widgetConfig",
                    WebRequest.SCOPE_REQUEST);
            String widgetPreferenceName = getWidgetPreferenceName(methodParameter, widgetPreference);
            if (widgetConfig != null) {
                String defaultValue = widgetPreference.defaultValue();
                Object value = widgetConfig.getPreferences().get(widgetPreferenceName);
                if (StringUtils.hasText(defaultValue) && value == null) {
                    value = defaultValue;
                }
                //
                if (widgetPreference.required()) {
                    Assert.notNull(value, String.format("Widget preference %s can not be null!", value));
                }
                //
                return value;
            }
        }
        //
        return null;
    }

    private String getWidgetPreferenceName(MethodParameter methodParameter, WidgetPref widgetPreference) {
        String widgetPreferenceName = methodParameter.getParameterName();
        //
        if (StringUtils.hasText(widgetPreference.value())) {
            widgetPreferenceName = widgetPreference.value();
        }
        //
        return widgetPreferenceName;
    }
}