org.appcomponents.platform.mvc.PlatformRequestMappingHandlerMapping.java Source code

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Here is the source code for org.appcomponents.platform.mvc.PlatformRequestMappingHandlerMapping.java

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/*
 * Copyright 2016 the original author or authors.
 *
 * 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/>.
 */
package org.appcomponents.platform.mvc;

import java.util.Map;

import javax.servlet.http.HttpServletRequest;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.appcomponents.platform.api.Component;
import org.appcomponents.platform.api.PlatformComponent;
import org.appcomponents.platform.http.ComponentRelativeHttpServletRequest;

import org.springframework.beans.BeansException;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;
import org.springframework.core.Ordered;
import org.springframework.core.annotation.Order;
import org.springframework.web.servlet.HandlerExecutionChain;
import org.springframework.web.servlet.HandlerMapping;

/**
 * Platform request handler. Handler is responsible for handling request between App Components.
 * @author Martin Janys
 */
@Order(Ordered.HIGHEST_PRECEDENCE)
public class PlatformRequestMappingHandlerMapping implements HandlerMapping, ApplicationContextAware {

    private ApplicationContext applicationContext;
    protected static final Log logger = LogFactory.getLog(PlatformRequestMappingHandlerMapping.class);

    @Override
    public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
        this.applicationContext = applicationContext;
    }

    @Override
    public HandlerExecutionChain getHandler(HttpServletRequest request) throws Exception {
        PlatformComponent platform = this.applicationContext.getBean(PlatformComponent.class);
        Component component = resolveComponent(platform, request);
        if (component != null) {
            if (!component.useContextPath()) {
                return handle(request, component);
            } else {
                ComponentRelativeHttpServletRequest relativeRequest = new ComponentRelativeHttpServletRequest(
                        request, component.getComponentName());
                return handle(relativeRequest, component);
            }
        } else {
            return null;
        }
    }

    protected Component resolveComponent(PlatformComponent platform, HttpServletRequest request) {
        String componentName = request.getParameter(PlatformComponent.PARAM_COMPONENT);
        if (PlatformComponent.NONE_COMPONENT.equals(componentName)) {
            return platform.getRootComponent();
        } else {
            for (Component component : platform.getComponents()) {
                if (component.useContextPath()
                        && isComponentRelativePath(component.getComponentName(), request.getRequestURI())) {
                    return component;
                } else if (component.getComponentName().equals(componentName)) {
                    return component;
                }
            }
            return platform.getDefaultComponent();
        }
    }

    private boolean isComponentRelativePath(String componentName, String requestURI) {
        return requestURI.startsWith("/" + componentName);
    }

    protected HandlerExecutionChain handle(HttpServletRequest request, Component component) throws Exception {
        ApplicationContext applicationContext = component.getApplicationContext();
        if (this.applicationContext.equals(applicationContext)) {
            return null;
        } else {
            Map<String, HandlerMapping> handlerMappingMap = applicationContext.getBeansOfType(HandlerMapping.class);
            for (HandlerMapping hm : handlerMappingMap.values()) {
                if (hm.getClass().equals(getClass())) {
                    continue;
                }
                if (logger.isTraceEnabled()) {
                    logger.trace("Testing handler map [" + hm + "] in PlatformRequestMappingHandlerMapping");
                }
                HandlerExecutionChain handler = hm.getHandler(request);
                if (handler != null) {
                    return handler;
                }
            }
            return null;
        }
    }
}