HttpHeaderViewResolver.java

package com.swazzy.viewresolver;

import java.util.Iterator;
import java.util.List;
import java.util.Locale;
import java.util.Map;

import org.apache.log4j.Logger;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.mobile.device.Device;
import org.springframework.mobile.device.DeviceUtils;
import org.springframework.web.context.request.RequestContextHolder;
import org.springframework.web.context.request.ServletRequestAttributes;
import org.springframework.web.servlet.View;
import org.springframework.web.servlet.view.ContentNegotiatingViewResolver;

import com.swazzy.controller.UserAgent;

public class HttpHeaderViewResolver extends ContentNegotiatingViewResolver {
  /**
	 * @return the viewPrefixPattern
	 */

	static Logger log = Logger.getLogger(HttpHeaderViewResolver.class);
	private String headerParam;
	private Map<String, String> viewPrefixPattern;
	@Autowired
	UserAgent userAgent;

	@Override
	public View resolveViewName(String viewName, Locale locale)
			throws Exception {
		// Get the HTTP Header param "User-Agent"
		String headerParamValue = ((ServletRequestAttributes) RequestContextHolder
				.getRequestAttributes()).getRequest().getHeader(headerParam);

		viewName = setViewName(viewName, headerParamValue);

		return super.resolveViewName(viewName, locale);
	}

	private String setViewName(String viewName, String headerParamValue) {

		if (userAgent.isRobot()) {
			log.debug("Forwarding to robots/" + viewName);
			return "robots/" + viewName;
		} else if (userAgent.isMobile()) {
			log.debug("Forwarding to mobile/" + viewName);
			return "mobile/" + viewName;
		}

		return viewName;
	}

	/**
	 * @return the headerParam
	 */
	public String getHeaderParam() {
		return headerParam;
	}

	/**
	 * @param headerParam
	 *            the headerParam to set
	 */
	public void setHeaderParam(String headerParam) {
		this.headerParam = headerParam;
	}

	/**
	 * @return the viewPrefixPattern
	 */
	public Map<String, String> getViewPrefixPattern() {
		return viewPrefixPattern;
	}

	/**
	 * @param viewPrefixPattern
	 *            the viewPrefixPattern to set
	 */
	public void setViewPrefixPattern(Map<String, String> viewPrefixPattern) {
		this.viewPrefixPattern = viewPrefixPattern;
	}

}

mvc-context.xml

<beans xmlns="http://www.springframework.org/schema/beans"
  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:context="http://www.springframework.org/schema/context"
	xmlns:mvc="http://www.springframework.org/schema/mvc" xmlns:util="http://www.springframework.org/schema/util"
	xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
		http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.0.xsd
		http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-3.0.xsd
		http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util-3.0.xsd">

	<context:component-scan base-package="com.swazzy.mvc" />

	<mvc:annotation-driven />
	<bean id="tilesViewResolver"
		class="org.springframework.web.servlet.view.UrlBasedViewResolver">
		<property name="viewClass"
			value="org.springframework.web.servlet.view.tiles2.TilesView" />
	</bean>
	<bean id="viewResolver"
		class="org.springframework.web.servlet.view.InternalResourceViewResolver">
		<property name="prefix" value="/WEB-INF/views/" />
		<property name="suffix" value=".jsp" />
		<property name="order" value="1" />
	</bean>

	<mvc:resources mapping="/static/**" location="/" />
	<mvc:interceptors>
		<bean
			class="org.springframework.mobile.device.DeviceResolverHandlerInterceptor" />
	</mvc:interceptors>
	<mvc:default-servlet-handler />

	<!-- freemarker config -->
	<bean id="freemarkerConfig"
		class="org.springframework.web.servlet.view.freemarker.FreeMarkerConfigurer">
		<property name="templateLoaderPath" value="/WEB-INF/views/" />
	</bean>
	<bean id="ftlViewResolver"
		class="org.springframework.web.servlet.view.freemarker.FreeMarkerViewResolver">
		<property name="cache" value="true" />
		<property name="prefix" value="" />
		<property name="suffix" value=".ftl" />
		<property name="order" value="0" />
	</bean>
	<bean id="HttpHeaderViewResolver" class="com.swazzy.viewresolver.HttpHeaderViewResolver">
		<property name="viewResolvers">
			<list>
				<ref bean="viewResolver" />
				<ref bean="ftlViewResolver" />
			</list>
		</property>
		<property name="headerParam" value="User-Agent" />
		<property name="viewPrefixPattern" ref="userAgentPatterns" />
	</bean>
</beans>

pom.xml

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
      <dependencies>
      <dependency>
  		<groupId>cglib</groupId>
			<artifactId>cglib-nodep</artifactId>
			<version>2.2.2</version>
			<scope>test</scope>
		</dependency>
		<dependency>
			<groupId>cglib</groupId>
			<artifactId>cglib</artifactId>
			<version>2.2.2</version>
		</dependency>
      <dependency>
			<groupId>org.freemarker</groupId>
			<artifactId>freemarker</artifactId>
			<version>2.3.19</version>
		</dependency>
    <dependency>
  		<groupId>org.springframework.mobile</groupId>
			<artifactId>spring-mobile-device</artifactId>
			<version>1.1.0.M1</version>
		</dependency>
    </dependencies>
  </project>

user-agents.xml

<beans xmlns="http://www.springframework.org/schema/beans"
  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:context="http://www.springframework.org/schema/context"
	xmlns:mvc="http://www.springframework.org/schema/mvc" xmlns:util="http://www.springframework.org/schema/util"
	xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
		http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.0.xsd
		http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc-3.0.xsd
		http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util-3.0.xsd">	
	<util:map id="userAgentPatterns" map-class="java.util.HashMap" key-type="java.lang.String" value-type="java.lang.String">
		<entry key="search-robot" value=".*(Googlebot|Yahoo|bingbot|acoon|aibot|AltaVista|amzn_assoc|ASPSeek|augurfind|Bigsearch|BlogSearch|DataparkSearch|search).*" />
	</util:map>
	</beans>

UserAgent.java

package com.swazzy.controller;

import java.util.Iterator;
import java.util.Map;
import java.util.Map.Entry;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

import javax.annotation.PostConstruct;
import javax.annotation.Resource;
import javax.servlet.http.HttpServletRequest;

import org.apache.http.HttpRequest;
import org.apache.log4j.Logger;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.context.annotation.Scope;
import org.springframework.mobile.device.Device;
import org.springframework.mobile.device.DeviceUtils;
import org.springframework.stereotype.Component;
import org.springframework.web.context.request.RequestContextHolder;
import org.springframework.web.context.request.ServletRequestAttributes;

/**
 * 
 * @author "Alexander D. Mahabir"
 *
 */
@Component("userAgent")
@Scope("session")
public class UserAgent implements Device{
  static Logger log = Logger.getLogger(UserAgent.class);
	private String useragent;
	private Device device;
	private String type;
	private static final String USER_AGENT="User-Agent";
	
	@Resource
	@Qualifier("userAgentPatterns")
	private Map<String, String> userAgentPatterns;
	boolean set=false;
	boolean robot=false;
	/**
	 * 
	 * @return
	 */
	public boolean isRobot() {
		return robot;
	}
	/**
	 * 
	 */
	@Override
	public boolean isMobile() {
		return device.isMobile();
	}
	/**
	 * 
	 */
	@Override
	public boolean isTablet() {
		return device.isTablet();
	}
	
	/**
	 * @return the useragent
	 */
	public String getUseragent() {
		return useragent;
	}
	/**
	 * @param useragent the useragent to set
	 */
	public void setUseragent(String useragent) {
		this.useragent = useragent;
	}
	/**
	 * @return the device
	 */
	public Device getDevice() {
		return device;
	}
	/**
	 * @param device the device to set
	 */
	public void setDevice(Device device) {
		this.device = device;
	}
	/**
	 * @return the type
	 */
	public String getType() {
		return type;
	}
	/**
	 * @param type the type to set
	 */
	public void setType(String type) {
		this.type = type;
	}
	/**
	 * 
	 * @param useragent
	 * @param device
	 * @param type
	 */
	public UserAgent(String useragent, Device device, String type) {
		super();
		this.useragent = useragent;
		this.device = device;
		this.type = type;
		this.set=true;
	}
	/**
	 * 
	 */
	public UserAgent() {
		super();
	
	}
	/**
	 * 
	 */
	@PostConstruct
	private void init() {
		try {
			HttpServletRequest request = ((ServletRequestAttributes) RequestContextHolder
					.getRequestAttributes()).getRequest();

			device = DeviceUtils.getCurrentDevice(request);
			this.useragent = request.getHeader(USER_AGENT);
			parseTypes();

			this.set = true;
		} catch (Exception e) {
		}
	}
	/**
	 * 
	 */
	private void parseTypes() {
		Iterator<Entry<String, String>> it = userAgentPatterns.entrySet().iterator();
		while (it.hasNext()) {
			Map.Entry<String, String> pairs = (Map.Entry<String, String>) it
					.next();
			Pattern pattern = Pattern.compile(pairs.getValue(), Pattern.CASE_INSENSITIVE);
			Matcher matcher = pattern.matcher(useragent);
			if (matcher.find()) {
				switch (pairs.getKey()) {
				case "search-robot":
					this.robot = true;
					break;
				default:
					break;
				}
				this.type = pairs.getKey();
			}
			
		}

	}
	/**
	 * @return the set
	 */
	public boolean isSet() {
		return set;
	}
	/**
	 * @param set the set to set
	 */
	public void setSet(boolean set) {
		this.set = set;
	}

	@Override
	public boolean isNormal() {
		return device.isNormal();
	}
	/* (non-Javadoc)
	 * @see java.lang.Object#toString()
	 */
	@Override
	public String toString() {
		return String
				.format("UserAgent [useragent=%s, device=%s, type=%s, userAgentPatterns=%s, set=%s, robot=%s]",
						useragent, device, type, userAgentPatterns, set, robot);
	}
	/**
	 * @return the userAgentPatterns
	 */
	public Map<String, String> getUserAgentPatterns() {
		return userAgentPatterns;
	}
	/**
	 * @param userAgentPatterns the userAgentPatterns to set
	 */
	public void setUserAgentPatterns(Map<String, String> userAgentPatterns) {
		this.userAgentPatterns = userAgentPatterns;
	}
	
	
}