com.kodgemisi.common.thymeleaf.ThymeleafLayoutInterceptor.java Source code

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Here is the source code for com.kodgemisi.common.thymeleaf.ThymeleafLayoutInterceptor.java

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package com.kodgemisi.common.thymeleaf;/*
                                       * Copyright (c) June 2016, Kod Gemisi Ltd. dev@kodgemisi.com
                                       *
                                       * This file is a part of "suite-ui" project and this license applies to
                                       * the whole project unless explicitly stated otherwise.
                                       *
                                       * This program is free software: you can redistribute it and/or modify
                                       * it under the terms of the GNU Affero General Public License as
                                       * published by the Free Software Foundation, either version 3 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 Affero General Public License for more details.
                                       *
                                       * You should have received a copy of the GNU Affero General Public License
                                       * along with this program.  If not, see <http://www.gnu.org/licenses/>.
                                       */

import org.springframework.util.Assert;
import org.springframework.web.method.HandlerMethod;
import org.springframework.web.servlet.ModelAndView;
import org.springframework.web.servlet.handler.HandlerInterceptorAdapter;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

public class ThymeleafLayoutInterceptor extends HandlerInterceptorAdapter {

    private static final String DEFAULT_LAYOUT = "layouts/default";
    private static final String DEFAULT_VIEW_ATTRIBUTE_NAME = "view";

    private String defaultLayout = DEFAULT_LAYOUT;
    private String viewAttributeName = DEFAULT_VIEW_ATTRIBUTE_NAME;

    public void setDefaultLayout(String defaultLayout) {
        Assert.hasLength(defaultLayout);
        this.defaultLayout = defaultLayout;
    }

    public void setViewAttributeName(String viewAttributeName) {
        Assert.hasLength(defaultLayout);
        this.viewAttributeName = viewAttributeName;
    }

    @Override
    public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler,
            ModelAndView modelAndView) throws Exception {
        if (modelAndView == null || !modelAndView.hasView()) {
            return;
        }
        String originalViewName = modelAndView.getViewName();
        if (shouldDecorationAvoided(originalViewName)) {
            return;
        }

        // When using custom login page with Spring-Security, login page's controller is of type ParameterizableViewController
        // We'd better render it without any layout as it's just the login page.
        // Note that this behavior is project dependent.
        if (!(handler instanceof HandlerMethod)) {
            return;
        }

        String layoutName = getLayoutName(handler);
        modelAndView.setViewName(layoutName);
        modelAndView.addObject(this.viewAttributeName, originalViewName);
    }

    /**
     * @param viewName
     * @return true if this view shouldn't be decorated
     */
    private boolean shouldDecorationAvoided(String viewName) {
        return viewName.startsWith("redirect:") || viewName.startsWith("forward:") || viewName.equals("error");
    }

    private String getLayoutName(Object handler) {
        HandlerMethod handlerMethod = (HandlerMethod) handler;
        Layout layout = getMethodOrTypeAnnotation(handlerMethod);
        if (layout == null) {
            return this.defaultLayout;
        } else {
            return layout.value();
        }
    }

    private Layout getMethodOrTypeAnnotation(HandlerMethod handlerMethod) {
        Layout layout = handlerMethod.getMethodAnnotation(Layout.class);
        if (layout == null) {
            return handlerMethod.getBeanType().getAnnotation(Layout.class);
        }
        return layout;
    }
}