Tag Archives: web

Angular-js and Restful web services access

Following my previous article about the integration of Spring Security with web services, I will now explain how I integrate it with an Angular-js project.
For that purpose, I am a little bit lazy and I use a project I already written instead of building a completely new one.

The project is a “funny” pet-store based on Spring boot (I like it definitely!), using an H2 database and Flyway to restore its content at each start.
The full project is available on Github.

The web services are defined with Spring MVC in the net.classnotfound.pet.web.PetController:

package net.classnotfound.pet.web;
...
@RestController
public class PetController {
	
	@Autowired
	private PetService petService;
	
	@RequestMapping(value = "/pet/all", method = RequestMethod.GET)
	@ResponseBody
	public Collection<JsonPet> findAll() {
		...
	}
	
	@Transactional(propagation= Propagation.SUPPORTS)
	@RequestMapping(value = "/pet/{id}", method = RequestMethod.GET)
	@ResponseBody
	public JsonPet find(@PathVariable("id") final Integer id) {
		...
	}

	@Transactional(propagation= Propagation.REQUIRED)
	@RequestMapping(value = "/pet", method = RequestMethod.POST, consumes = {"application/json" })
	@ResponseStatus(HttpStatus.CREATED)
	public @ResponseBody JsonPet save(@RequestBody final JsonPet jsonPet) {
		...
	}
}

The PetService is the class responsible of business processes (mainly access data here).

We can see that there are 3 actions available to:

  • display the list of pets in the store
  • display the detail of a pet
  • create a “new” pet in the store

The attributes of the requestMapping annotation seem explicit, for example, with @RequestMapping(value = “/pet”, method = RequestMethod.POST, consumes = {“application/json” }), I express that the method can be reach with /pet URL, by using the POST method and it needs json.
Based on Spring, the conversion from Json to Java Object (and the opposite) is totally hidden (it relies on Jackson API) and it avoid this burden to the developer (meaning me, here!).

Now that the landscape is set, let’s have a look at the security configuration (it should be familiar to whose who read my previous article):

@Override
protected void configure(AuthenticationManagerBuilder auth) throws Exception {
	auth.inMemoryAuthentication().
	  withUser("admin").password("password").roles("ADMIN", "USER").and().
	  withUser("user").password("password").roles("USER");
}

@Override
protected void configure(HttpSecurity http) throws Exception { 
	
	http
	.csrf().disable()
	.authorizeRequests()
	.antMatchers("/login").anonymous()
	.antMatchers(HttpMethod.GET, "/pet/**").access("hasRole('USER')")
	.antMatchers(HttpMethod.POST, "/pet/**").access("hasRole('ADMIN')");
	
	http.exceptionHandling().authenticationEntryPoint(authenticationEntryPoint);
	FormLoginConfigurer formLogin = http.formLogin();
	formLogin.loginProcessingUrl("/login");
	formLogin.usernameParameter("username");
	formLogin.passwordParameter("password");
	formLogin.successHandler(authenticationSuccessHandler);
	formLogin.failureHandler(authenticationFailureHandler);
	
}

I started with the users definition with their roles.
And after that, Y can see how I restricted access to the features, as previously, I disabled the CSRF protection but I will come back to it in a next article.

Now, if a unauthenticated user tries to access the protected resources, he will receive an HTTP 401 error. Let’s see how I deal with it on the client side (Angular-js).
The web pages are located in

The idea is to have the generic process to intercept the right HTTP code when the user needs to be authenticated, and redirect him automatically to the login page .
The application is based on the single page principle, for that purpose, I use the ngRoute module, it is configured in the app.js file:

petstoreApp.config(['$routeProvider',
  function($routeProvider) {
    $routeProvider.
      when('/pets', {
	      templateUrl: 'partials/pet-list.html',
	      controller: 'PetListCtrl'
      }).
      when('/pets/new', {
    	  templateUrl: 'partials/pet-new.html',
    	  controller: 'PetNewCtrl'
      }).
      when('/pets/:petId', {
          templateUrl: 'partials/pet-detail.html',
          controller: 'PetDetailCtrl'
      }).
      when('/login', {
          templateUrl: 'partials/login.html',
          controller: 'LoginCtrl'
        }).
      otherwise({
        redirectTo: '/pets'
      });
  }]);

As expected, we can find our 3 pages related to the web services features and another one to ask credentials to users. This one will be used when redirecting unauthenticated users.
For that purpose, the application is configured with an Angular-js interceptor. All the requests sent or received can be manipulated by interceptor, this is very useful for common purposes like error management or authentication, and it is exactly the way I use it (still in the app.js file):

petstoreApp.factory('errorInterceptor', ['$q', '$location', '$window', '$injector', function($q, $location, $window, $injector) {
	var authSrv;
	var popupSrv;
	var errorInterceptor = {
			'responseError' : function(rejection) {
				var status = rejection.status;
				if (rejection.data){
					if (status == 401) {//Unauthenticated, redirect to login page
						$window.location.href="/#/login";
						return;
					} else if (status == 418) {//undefined error->HTTP code 418 ( I'm a teapot) is responsibility of the caller
						return $q.reject(rejection);
					} else{
						popupSrv = popupSrv || $injector.get('popUpSrv');
						popupSrv.alert("Erreur: "+rejection.data.message+ (rejection.data.stackTrace?"\r\n___________________________________\r\n\r\nErreur complète:\r\n" + rejection.data.stackTrace:''));
						return;
					} 
				} else {
					popupSrv = popupSrv || $injector.get('popUpSrv');
					popupSrv.alert("Erreur inconnue( http status: "+status+")");
					return;
				}
				return $q.reject(rejection);
			}};
	return errorInterceptor;
}]);
petstoreApp.config(['$httpProvider', function($httpProvider) {  
    $httpProvider.interceptors.push('errorInterceptor');
}]);

The interceptor is in charge of managing the HTTP 401 code by redirecting to the login form, and also of the display of a generic message error.
For more information about interceptors and their usage, you can directly have a look at the official site.

And now, it works! The web site can access resources protected with Spring security. In the real world, I should display the new pet button only for admin users, it means that I should also provide a service indicate which actions are available for a user.

For those who missed the point, the sources of the project are available here.

Add CORS management with Tomcat and Angular-Js

In one of my projects, I decided to setup a SOA architecture using Angular-Js as the UI layer. My main focus is to have a clear separation between the business and the presentation. Another benefit of this is that it is possible the use different servers to these 2 parts.
But doing this causes an issue, because of security, an Ajax request cannot connect to a server which is in another domain from where it is originated. It is done like that to avoid some malicious code executed in a page sends information to another server but in my case, it’s a problem. This behavior is called the Cross-origin Resource Sharing and fortunately, most modern browsers (it excludes IE) can deal with this but the server needs more configuration.
On the server side (Tomcat), there is a provided filter that we need to add to our web configuration (CorsFilter).
In the web.xml, we add:

<filter>
    <filter-name>CorsFilter</filter-name>
    <filter-class>org.apache.catalina.filters.CorsFilter</filter-class>
    <init-param>
        <param-name>cors.allowed.origins</param-name>
        <param-value>*</param-value>
    </init-param>
    <init-param>
        <param-name>cors.allowed.methods</param-name>
        <param-value>GET,POST,HEAD,OPTIONS,PUT,DELETE</param-value>
    </init-param>
</filter>

I added also some parameters but the default values should be enough.

Now, the server can manage the headers sent by the browser and with this configuration, the filter will automatically allow the request, it is also possible to configure the filter to restrict access to certain domains, but in my case, as I am already in a restricted network, it is not needed.

Another issue I encountered was with the web session. My services need an authenticated user, it is done using an authentication page and a web session. But when the CORS principle is used, by default, the browser does not send the session cookie, to enable it, I added in my Angular app:

var classNotFound = angular.module('classNotFound', ['ngRoute', 'ui.bootstrap', ...])
	.config(['$httpProvider', function($httpProvider) {//mandatory to enable cors feature (http://en.wikipedia.org/wiki/Cross-origin_resource_sharing)
		$httpProvider.defaults.withCredentials = true;
	}])

Now it works!

Multithreading and Spring Security

I manage a Spring project where I need to create a new thread to launch an asynchronous task. This project uses Spring Security and an Oracle proxy user (I will describe it in a future post), which means that, for each starting transaction, a call is made to the security context to get the current user.
The problem is that the new thread must access the database, then it tries to access the security context managed by Spring. But as Spring Security uses a ThreadLocal to store the security context, I receive the usual NullPointerException.
But fortunately, Spring is a well designed API and I can solve this issue by simply adding the security context to the thread:

public class CalculatorTask{
    public CalculatorTask(final Data data, final MyDao dao, final SecurityContext context) {
        super();
        this.data = data;
        this.myDao = dao;
        this.context = context;
    }

    @Override
    @Transactional
    public void run() {
        LOG.info("Starting asynchronous calculation");
        SecurityContextHolder.setContext(context);
        myDao.doStuff(data);
        //Make here some amazing action
        ...
        LOG.info("Finishing asynchronous calculation");
    }
}

Note that the context is only set in the run() method.

And how I call it:

public class MyClass {
    private static final Logger LOG = LoggerFactory.getLogger(BsBillSetServiceImpl.class);

    @Autowired
    private TaskExecutor executor;

    @Autowired
    private MyDao myDao;

    @Override
    public void calcul(final  Object data) {
        
        SecurityContext context = SecurityContextHolder.getContext();

        CalculatorTask CalculatorTask = new CalculatorTask(data, myDao, context);
        executor.execute(CalculatorTask);
        LOG.info("The calculation has been launched");
    }
}

So simple even if at the first beginning, it was more like “What the f…!!!” 😀

Define configuration file outside of the classpath

Here I describe the way I use to configure my applications. The main idea is to define a property file outside of the application, doing this, it is possible to deploy the same application in several environments (dev/test/prod) without any changes.

First of all, the property file:

net.classnotfound.app.jdbc.server=db-server
net.classnotfound.app.jdbc.port=1521
net.classnotfound.app.jdbc.sid=xe
net.classnotfound.app.jdbc.user=scott
net.classnotfound.app.jdbc.password=koala

The tips is to define a parameter in the Tomcat context file which points to the file location:

<Parameter name="directoryConfig" override="false" value="FILE_PATH"/>

And now, to get the value in the application, I use Spring this way:

<bean id="placeholderConfig"
	class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer">
	<property name="location"
		value="file:#{contextParameters.directoryConfig}/app-config.properties" />
</bean>

This is an example of its usage to set up an Oracle datasource:

<orcl:pooling-datasource id="dataSource"
	url="jdbc:oracle:thin:@${net.classnotfound.app.jdbc.server}:${net.classnotfound.app.jdbc.port}:${net.classnotfound.app.jdbc.sid}"
	username="${net.classnotfound.app.jdbc.user}" password="${net.classnotfound.app.jdbc.password}">
</orcl:pooling-datasource>

Now, we can just change the path of the configuration file, depending on each environment, to automatically have the related parameters.

Spring Security with JSF 2 and custom login form

Here, I am integrating Spring Security with JSF 2 using a custom login form.

First, the maven dependencies for Spring-Security (I consider that the JSF project is already set-up, if it is not the case, you can check here):

<properties>
    ...
    <spring.security.version>3.2.4.RELEASE</spring.security.version>
</properties>
...
<!-- Spring-Security dependencies -->
<dependency>
    <groupId>org.springframework.security</groupId>
    <artifactId>spring-security-core</artifactId>
    <version>${spring.security.version}</version>
</dependency>
<dependency>
    <groupId>org.springframework.security</groupId>
    <artifactId>spring-security-config</artifactId>
    <version>${spring.security.version}</version>
</dependency>
<dependency>
    <groupId>org.springframework.security</groupId>
    <artifactId>spring-security-web</artifactId>
    <version>${spring.security.version}</version>
</dependency>

In the web.xml, we have to configure the Spring-Security filter as follow:

<!-- Enable Spring Filter: Spring Security works on the concept of Filters -->
<!-- Declare the Spring filter -->
<filter>
    <filter-name>springSecurityFilterChain</filter-name>
    <filter-class>
        org.springframework.web.filter.DelegatingFilterProxy
    </filter-class>
</filter>
<!-- Defines urls pattern on which the filter is applied -->
<filter-mapping>
    <filter-name>springSecurityFilterChain</filter-name>
    <url-pattern>/*</url-pattern>
    <dispatcher>FORWARD</dispatcher>
    <dispatcher>REQUEST</dispatcher>
</filter-mapping>

Note: if you don’t add the forward to it, the managed bean will not be able to send the request to the filter (I experienced that!!).

We need a simple index.xhtml which will be protected by Spring (I don’t describe it here) and a custom login page which receive the credentials typed by the user.
This page contains only the user name, the password and another field method which is here to show how we can get it on the server:

<h:form id="loginFormId" prependId="false">
    <div class="full-box" style="text-align: center">
        <div class="child-box box-c3">
            <h3>Login</h3>
            <div class="fluid-row">
                <div class="fluid-column fluid-c12">
                    <div class="forLabel" style="width: 30%">
                        <h:outputLabel for="username" value="User" />
                    </div>
                    <div class="forField" style="width: 65%">
                        <h:inputText id="username" required="true"
                            requiredMessage="Please enter username (or go to hell...)" />
                        <h:messages for="username" />
                    </div>
                </div>
                <div class="fluid-column fluid-c12">
                    <div class="forLabel" style="width: 30%">
                        <h:outputLabel for="password" value="Password" />
                    </div>
                    <div class="forField" style="width: 65%">
                        <h:inputSecret id="password" required="true"
                            requiredMessage="Please enter password (otherwise you'll die!!)"
                            name="password" />
                        <h:messages for="password" />
                    </div>
                </div>
                <div class="fluid-column fluid-c12">
                    <div class="forLabel" style="width: 30%">
                        <h:outputText value="Authentication" />
                    </div>
                    <div class="forField" style="width: 65%">
                        <h:selectBooleanCheckbox id="method" name="method" />
                        <h:outputLabel for="method" value="LDAP" />
                    </div>
                </div>
            </div>
            <ui:fragment rendered="${!empty param['error']}">
                <div>Connection failed: user and/or password are wrong.</div>
            </ui:fragment>
            <div id="loginBtnPanelId">
                <h:commandButton id="btnLoginId" value="Login" type="submit"
                    action="${loginManager.doLogin()}" styleClass="loginPanelBtn" />
            </div>
        </div>
    </div>
</h:form>

The form is very simple, we can see the 3 fields and a portion which is conditionally rendered if error param is available.
The content of this form is sent to a managed bean which is responsible of forwarding data to the Spring-Security filter:

import java.io.IOException;

import javax.faces.bean.ManagedBean;
import javax.faces.bean.RequestScoped;
import javax.faces.context.ExternalContext;
import javax.faces.context.FacesContext;
import javax.servlet.RequestDispatcher;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;

@ManagedBean
@RequestScoped
public class LoginManager {

    public String doLogin() throws IOException, ServletException {
        ExternalContext context = FacesContext.getCurrentInstance().getExternalContext();
        RequestDispatcher dispatcher = ((ServletRequest) context.getRequest()).getRequestDispatcher("/j_spring_security_check");
        dispatcher.forward((ServletRequest) context.getRequest(), (ServletResponse) context.getResponse());
        FacesContext.getCurrentInstance().responseComplete();
        return null;
    }

}

Now, we need to have a look to the Spring configuration file, the security is configured as follow:

<security:http use-expressions="true">
    <!-- refers to http://docs.spring.io/spring-security/site/docs/3.0.x/reference/el-access.html -->
    <security:intercept-url pattern="/faces/login.xhtml"
        access="anonymous" />
    <security:intercept-url pattern="/css/**"
        access="anonymous" />
    <security:intercept-url pattern="/**"
        access="authenticated" />
    <security:form-login login-page="/faces/login.xhtml"
        authentication-failure-url="/faces/login.xhtml?error=1"
        default-target-url="/faces/index.xhtml"
        authentication-details-source-ref="myAuthenticationDetailsSource"
        username-parameter="username" password-parameter="password" />
</security:http>

We can see that we have to enable anonymous access to the login form (otherwise, you will see some strange messages in your browser, I let you guess why). To have a beautiful login page, we also allow anonymous access to the CSS, the rest of the site has a restricted access controlled by Spring.
As we use a custom login form, the form-login element must indicate which one we want to use with the login-page attribute.
To be able to store the custom field (the method if you forgot it), we have to implement a custom class, it is the one we see in the authentication-details-source-ref attribute.

This is how it is defined in the Spring configuration file:

<bean id="myAuthenticationDetailsSource"
    class="net.classnotfound.jsf.spring.security.security.MyAuthenticationDetailsSource">
</bean>

And the class which implements the org.springframework.security.authentication.AuthenticationDetailsSource interface:

import javax.servlet.http.HttpServletRequest;

import org.springframework.security.authentication.AuthenticationDetailsSource;
import org.springframework.security.web.authentication.WebAuthenticationDetails;

/**
 * This class provides a custom AuthenticationDetail which stores the connection
 * type method (Oracle/Ldap)
 *
 */
public class MyAuthenticationDetailsSource implements AuthenticationDetailsSource {

    /**
     * returns the {@link WebAuthenticationDetails} according to LuxFact rule
     * 
     * @param context
     */
    @Override
    public WebAuthenticationDetails buildDetails(final HttpServletRequest context) {
        return new MyAuthenticationDetails(context);
    }

}

This class provides an implementation of a org.springframework.security.web.authentication.WebAuthenticationDetails which will store our extra parameter, its implementation is very simple:

import javax.servlet.http.HttpServletRequest;

import org.springframework.security.web.authentication.WebAuthenticationDetails;

/**
 * this class stores data used for authentication (mainly the authentication
 * method)
 * 
 */
public class MyAuthenticationDetails extends WebAuthenticationDetails {

    /**
     * 
     */
    private static final long serialVersionUID = 1L;
    private final String method;

    public MyAuthenticationDetails(final HttpServletRequest request) {
        super(request);
        method = request.getParameter("method");
    }

    public String getMethod() {
        return method;
    }

}

As we can see, this class does nothing else than getting the custom parameter from the request and storing it.

Now, to use this extra parameter, we need to customize the way a user is authenticated. As this task is, by default, done by Spring, it means that we have to write a new class which implements the org.springframework.security.authentication.AuthenticationProvider interface. We can see its declaration in the Spring configuration file here:

<bean id="myAuthenticationProvider"
    class="net.classnotfound.jsf.spring.security.security.MyAuthenticationProvider">
</bean>

<security:authentication-manager>
    <!-- create a custom AuthenticationProvider class to tune the login 
        process -->
    <security:authentication-provider
        ref="myAuthenticationProvider" />
</security:authentication-manager>

And its implementation:

import org.springframework.security.authentication.AuthenticationProvider;
import org.springframework.security.authentication.BadCredentialsException;
import org.springframework.security.authentication.UsernamePasswordAuthenticationToken;
import org.springframework.security.core.Authentication;
import org.springframework.security.core.AuthenticationException;

public class MyAuthenticationProvider implements AuthenticationProvider {

    @Override
    public Authentication authenticate(final Authentication authentication) throws AuthenticationException {

        Authentication res = isValid(authentication);
        if (!res.isAuthenticated()) {
            throw new BadCredentialsException("Bad credentials");
        }
        return res;
    }

    private Authentication isValid(final Authentication authentication) {
        Authentication res = authentication;
        System.out.println("Selected method: "+((MyAuthenticationDetails)authentication.getDetails()).getMethod());
        if ("Admin".equals(authentication.getPrincipal())&&"Password".equals(authentication.getCredentials())) {
            res = createSuccessAuthentication(authentication);
        }
        return res;
    }

    @Override
    public boolean supports(final Class authentication) {
        return authentication.equals(UsernamePasswordAuthenticationToken.class);
    }

    protected Authentication createSuccessAuthentication(final Authentication authentication) {
        // Ensure we return the original credentials the user supplied,
        // so subsequent attempts are successful even with encoded passwords.
        // Also ensure we return the original getDetails(), so that future
        // authentication events after cache expiry contain the details
        final UsernamePasswordAuthenticationToken result = new UsernamePasswordAuthenticationToken(authentication.getPrincipal(), authentication.getCredentials(), authentication.getAuthorities());
        result.setDetails(authentication.getDetails());

        return result;
    }

}

As we can see, the extra parameter is extracted from the org.springframework.security.core.Authentication.getDetails() method.

The whole Spring configuration file looks like:

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
    xmlns:context="http://www.springframework.org/schema/context"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xmlns:security="http://www.springframework.org/schema/security"
    xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd
        http://www.springframework.org/schema/security http://www.springframework.org/schema/security/spring-security.xsd">


    <!-- Enable security annotations usage -->

    <bean id="myAuthenticationDetailsSource"
        class="net.classnotfound.jsf.spring.security.security.MyAuthenticationDetailsSource">
    </bean>

    <bean id="myAuthenticationProvider"
        class="net.classnotfound.jsf.spring.security.security.MyAuthenticationProvider">
    </bean>


    <security:authentication-manager>
        <!-- create a custom AuthenticationProvider class to tune the login 
            process -->
        <security:authentication-provider
            ref="myAuthenticationProvider" />
    </security:authentication-manager>

    <security:http use-expressions="true">
        <!-- refers to http://docs.spring.io/spring-security/site/docs/3.0.x/reference/el-access.html -->
        <security:intercept-url pattern="/faces/login.xhtml"
            access="anonymous" />
        <security:intercept-url pattern="/css/**"
            access="anonymous" />
        <security:intercept-url pattern="/**"
            access="authenticated" />
        <security:form-login login-page="/faces/login.xhtml"
            authentication-failure-url="/faces/login.xhtml?error=1"
            default-target-url="/faces/index.xhtml"
            authentication-details-source-ref="myAuthenticationDetailsSource"
            username-parameter="username" password-parameter="password" />
    </security:http>

</beans>

Source files are available here.

Change web context using Maven

<packaging>war</packaging>
<build>
<plugins>
  <plugin>
    <artifactId>maven-war-plugin</artifactId>
    <version>2.1.1</version>
    <configuration>
        <packagingExcludes>WEB-INF/web.xml</packagingExcludes>
        <warName>exp-elec-web</warName>
    </configuration>
</plugin>
</plugins>
</build>

Starting of Spring context in web application

Using Spring in a web application, we need to load the context when the application starts. Fortunately, it can be done in a simple way, by adding the right listener in the application web.xml.

Using Maven, you need to add the Spring-web dependency in your pom.xml:

<dependency>
  <groupId>org.springframework</groupId>
  <artifactId>spring-web</artifactId>
  <version>4.0.0.RELEASE</version>
  <scope>compile</scope>
</dependency>

And in the web.xml:

<listener>
    <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
</listener>

Access Spring context from web application

As I am using JSF with Spring, the beans managed by Spring are not accessible in my page, I used this Siegfried Bolz’s blog as a basis and used the facade pattern to hide access to the context.

The Spring context is loaded when the application starts using ContextLoaderListener in the apllication web.xml:

<listener>
    <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
</listener>

We need the following dependency:

<dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-web</artifactId>
    <version>4.0.0.RELEASE</version>
</dependency>

Define the object which will reference the Spring context:

package net.classnotfound.spring.context;

import org.springframework.context.ApplicationContext;

public class AppContext {
    private static ApplicationContext ctx;

    /**
     * Injected from the class "ApplicationContextProvider" which is automatically
     * loaded during Spring-Initialization.
     */
    public static void setApplicationContext(ApplicationContext applicationContext) {
        ctx = applicationContext;
    }

    /**
     * Get access to the Spring ApplicationContext from everywhere in your Application.
     *
     * @return
     */
    public static ApplicationContext getApplicationContext() {
        return ctx;
    }
}

Now, define the object that give you access to it:

package net.classnotfound.spring.context;

import org.springframework.beans.BeansException;
import org.springframework.context.ApplicationContext;
import org.springframework.context.ApplicationContextAware;
/**
 * This class provides an application-wide access to the 
 * Spring ApplicationContext! The ApplicationContext is 
 * injected in a static method of the class "AppContext". 
 * 
 * Use AppContext.getApplicationContext() to get access 
 * to all Spring Beans. 
 * 
 * @author Siegfried Bolz 
 *
 */
public class ApplicationContextProvider implements ApplicationContextAware {

    @Override
    public void setApplicationContext(ApplicationContext applicationContext) throws BeansException {
        AppContext.setApplicationContext(applicationContext);

    }

}

And now this is the facade object which gives access to the Spring beans:

package net.classnotfound.spring.context;

import org.springframework.context.ApplicationContext;

public class ServiceFacade {

	private static ServiceFacade instance = new ServiceFacade();
	
	private static ApplicationContext applicationContext;

	private ServiceFacade() {
		applicationContext = AppContext.getApplicationContext();
	}

	public static ServiceFacade getInstance() {
		return instance;
	}

	//Add here the method to get the different services available 
	// in the Spring Context
	public SpringBean getMyBean() {
		return (SpringBean) applicationContext.getBean("myBean");
	}
}

Don’t forget to ask Spring to create the bean:

<bean id="contextApplicationContextProvider" 
      class="net.classnotfound.spring.context.ApplicationContextProvider"/>

To use it:

SpringBean bean = ServiceFacade.getInstance().getMyBean();

Done!

Improve server startup using Informix and MyBatis

Working on a project with an Informix database and using MyBatis as the persistence layer, I noted that the start-up of the server takes a long time (about 2 minutes). It is not really a problem if the performance of the application are good, as you don’t start your server all the day, but when you are in the implementation phase…
After step-by-step execution, I discovered that MyBatis gathers the metadata of the database to adapt its behavior, but this part was responsible of the delay (maybe Informix specific?).
I decided to replace this step, fortunately, using MyBatis with Spring, it’s not really a big deal 🙂
As the main purpose of this step is to identify the database provider, I defined a class which returns always the same information: Informix database.

  1. first, you need to define a new DatabaseIdProvider:
    public class IfxDatabaseIdProvider 
            implements org.apache.ibatis.mapping.DatabaseIdProvider {
      
      private static final Log log = LogFactory.getLog(IfxDatabaseIdProvider.class);
    
      private Properties properties;
      
      public String getDatabaseId(DataSource dataSource) {
        
        return "Informix Dynamic Server";
      }
    
      public void setProperties(Properties p) {
        this.properties = p;
      }
    
      public Properties getProperties() {
        return properties;
      }
    }
    
  2. now, you need to tell to MyBatis to use the new class, your Spring config file looks like:

        <bean id="ifxDatabaseIdProvider" 
            class="myPackage.IfxDatabaseIdProvider"/>
        
        <bean id="sqlSessionFactory" 
            class="org.mybatis.spring.SqlSessionFactoryBean">
          <property name="dataSource" ref="dataSource" />
          <property name="mapperLocations" value="classpath:mapper/*Mapper.xml"/>
          <property name="databaseIdProvider" ref="ifxDatabaseIdProvider"/>
        </bean>
    

Done!

Tomcat Datasource configuration

I describe here my favorite solution to define the datasource of my web applications.

To do that in Tomcat :

  1. Copy the JDBC driver jar into the Tomcat lib directory
  2. define the datasource in the file server.xml:
     <GlobalNamingResources>
    
        <Resource 
            auth="Container" 
            driverClassName="oracle.jdbc.OracleDriver" 
            maxActive="20" 
            maxIdle="10" 
            maxWait="-1" 
            name="jdbc/myGlobalDatasource" 
            password="password" 
            type="javax.sql.DataSource" 
            url="jdbc:oracle:thin:@[server]:[port]:[sid]" 
            username="user"/>
    
    </GlobalNamingResources>
  3. map this datasource to your application using its context.xml file:
    <ResourceLink 
        global="jdbc/globalDatasource" 
        name="jdbc/applicationDatasource" 
        type="javax.sql.DataSource"/>
  4. And now, when you want to use it (using Spring):
    <bean id="dataSource" class="org.springframework.jndi.JndiObjectFactoryBean">
        <property name="jndiName" value="jdbc/applicationDatasource" />
        <property name="resourceRef" value="true" />
    </bean>

Done!

This example uses an Oracle connection but it can be easily adapted for another database.