Separate Properties from WAR

Separating properties from wars, there are many reasons and there are many ways. If you are still generating multiple wars, each for each level, you are out. Catch up, my friends, it is already the year of 2014.

Among all these almighty solutions, there is this simple and easy one, with JBoss 5.1.

First create a myapp-service.xml like this,

<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE server> <server> <mbean code="org.jboss.varia.property.SystemPropertiesService" name="jboss:type=Service,name=myappProperties"> <attribute name="URLList"> </attribute> <attribute name="Properties"> myapp.props1=aaa,bbb myapp.props2=http://whatever </attribute> </mbean> </server>

This myapp-server.xml will be deployed to JBoss deploy folder same as the war file.

Then in the appContext.xml, add a PropertyPlaceholderConfigurer.

<bean id="propertyPlaceholderConfigurer" class="org.springframework.beans.factory.config.PropertyPlaceholderConfigurer"> </bean>

Now you can use these properties in the appContext.xml like that,

<property name="defaultUri" value="${myapp.props2}">

To use the properties like myapp.props1, you need to define the field in the bean class like "private String[] props1;" then your props1 will be an array of aaa and bbb.

Now let's see that aaa and bbb need to be populated into a drop down list in HTML page.

First, create a JSON web service to serve the AJAX request. Remember, aaa and bbb will be sent down as {"aaa", "bbb"}.

In the HTML page, it will look like,

$.get("webservcieURL", function(props) { $.each(props, function(index, prop) { $("#mydropdownid").append($("<option/>", { value : prop, text : prop })); }); });

After selection, use $("#mydropdownid").val() to obtain the selected value. Remember it will be "aaa" or "bbb", not aaa or bbb. So when post it back to web service, use it straight forward, don't JSON stringfy it.

Use Maven to Manage Javascript Libraries

Usually we download javascript libraries and add them to web applications. It is simple and easy. However, it becomes headache when we need more and more libraries and the application grows big.

The problem is that some libraries are only compatible with others at certain versions. Also during the lifetime of the application, we need to add new features which will only be achievable with a newer version of some libraries. Now, are they still compatible? Or are they not anymore?

We will inevitably need to run testings back and forth to find the right mix. So what shall we do to minimize the hustle and headache?

Here is how I do it.

I download javascript libraries and install them into MyEclipse local maven repository. This is not ideal, because my teammates will need to repeat the installation. Ideally, we should be able to download it from central maven repository just like spring-core and spring-ws.

Webjars.org gives it a nice try to centralize popular javascript libraries and provide them as jar files. But I don't like its concept to use them as resources via classpath.

So I use maven overlays.

Here is how I define them in pom.xml.

... <plugin> <artifactid>maven-war-plugin</artifactId> <configuration> <failonmissingwebxml>false</failOnMissingWebXml> <overlays> <overlay> <groupid>org.jquery</groupId> <artifactid>ui</artifactId> <type>zip</type> <targetpath>includes/jquery.ui</targetPath> </overlay> ... <dependency> <groupid>org.jquery</groupId> <artifactid>ui</artifactId> <type>zip</type> <version>1.10.3</version> </dependency> ...

It's not over yet. The Maven install process will create a myApp.war file, but MyEclipse doesn't deploy it to my JBoss server. So again I turn to Maven to solve this problem.

Here is how I deploy myApp.war to my JBoss server.

... <plugin> <groupid>org.codehaus.cargo</groupId> <artifactid>cargo-maven2-plugin</artifactId> <executions> <execution> <id>deploy-localhost</id> <phase>install</phase> <goals> <goal>deploy</goal> </goals> </execution> </executions> <configuration> <container> <containerid>jboss51x</containerId> <home>${jboss.home}</home> <append>false</append> </container> <configuration> <type>existing</type> <home>${jboss.home}/server/default</home> <properties> <cargo.jboss.configuration>default</cargo.jboss.configuration> <cargo.rmi.port>1099</cargo.rmi.port> <cargo.logging>high</cargo.logging> </properties> </configuration> </configuration> </plugin> ...

I use cargo-maven2-plugin which is not ideal either. Simply because some guys keep on thinking older is better, instead of upgrading to JBoss 7, we stuck with JBoss 5.1. Otherwise, jboss-as-maven-plugin would be beautiful.

Besides I use ${jboss.home} to point to my JBoss installation which is very necessary. Because I will check in the pom.xml to Subversion and my teammates will get the same pom.xml. If I hard code my JBoss home directory here, they will need to change it for their environment. So the solution is to introduce the settings.xml.

<?xml version="1.0" encoding="UTF-8"?> <settings xmlns="http://maven.apache.org/SETTINGS/1.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/SETTINGS/1.0.0 http://maven.apache.org/xsd/settings-1.0.0.xsd"> <profiles> <profile> <id>dev</id> <properties> <jboss.home> C:/Dev_Tools/jboss-5.1.0.GA </jboss.home> </properties> </profile> </profiles> <activeprofiles> <activeprofile>dev</activeProfile> </activeProfiles> </settings>

This settings.xml needs to put under C:\Users\[userid]\.m2 directory.

Now everything should be good.

MyEclipse Install/Uninstall Zip File to Maven Local Repository

MyEcliplse Blue 10.7

For example, we downloaded jQuery 1.9.1 as jquery-1.9.1.zip. We need to install it to Maven local repository.

Here are the steps.

In MyEclipse, File -> Import, then expand Maven4MyEclipse, select Install or deploy an artifact to a Maven repository.

Browse... to enter the jquery-1.9.1.zip into the Artifact file field.

Leave POM file empty, leave Generate POM and Create Checksum as checked.

Set Group Id as org.jquery.

Set Artifact Id as core.

Set Version as 1.9.1.

Set Packaging as zip.

Leave Classifier empty.

Click on Finish and it is installed.

What if we don't like it and want to uninstall it?

Just change directory to C:\Users\[userid]\.m2\repository and find org\jquery\core. Remove the whole directory.

Come back to MyEclipse and go,

Preferences -> MyEclipse -> Maven4MyEclipse -> User Settings.

Then Reindex the local repository.

Continue: How the CastorMarshaller Mapping Look Like

I choose CastorMarshaller over Jaxb2Marshaller because I love what the mapping.xml gives me. It is powerful and flexible even though annotation is very cool.

I also choose not to generate the famous ObjectFactory and POJO from WSDL. Partially because I have to access a rather poor written WSDL. These generated classes bear names of non-sense and confusion. Also partially because I only need to access 20% of the web services. To bundle two sets of web services in one endpoint while knowing each set is designed for different purpose and different consumer is never a practice that I will consider in any near future.

Here is the mapping file. Note I can have any class name mapping to any soap name. And these Java classes are completely POJO.

<?xml version="1.0"?> <!DOCTYPE mapping PUBLIC "-//EXOLAB/Castor Mapping DTD Version 1.0//EN" "http://castor.codehaus.org/mapping.dtd"> <mapping> <description> Mapping the beans to SOAP web services. </description> <class name="com.mycomp.app2.beans.App2Request"> <map-to xml="soapRequestName" ns-prefix="prefix"/> <field name="fieldNameInPOJO" type="string"> <bind-xml name="elementNameInSOAP" node="element" /> </field> ... </class> <class name="com.mycomp.app2.beans.App2Response"> <map-to xml="soapResponseName" /> <field name="fieldNameInPOJO" type="com.mycomp.app2.beans.App2ResponseWrapper"> <bind-xml name="soapElementName" node="element" /> </field> </class> ... <class name="com.mycomp.app2.beans.App2ResponseWrapper"> <field name="collectionNameInPOJI" type="com.mycomp.app2.beans.App2ResponseEntry" collection="collection"> <bind-xml name="soapEntryName" /> </field> </class> ... </mapping>

According to CastorMarshaller documentation, ns-uri as attribute of the map-to definition promises the namespace declaration. For example, ns-prefix="myPrefix" and ns-uri="myServices" would create a SOAP request of myprefix:soaprequestname xmlns:myprefix="myServices", however, it only creates myprefix:soaprequestname xmlns:myprefix="null". For this, I don't understand why.

Continue: How WebServiceTemplate Look Like

So now we come down to the spring-ws which is relatively new to me. My goal is to access a SOAP web service and my plan is to create POJO requests and receive POJO responses by using the marshallSendAndReceive from WebServiceTemplate.

Here is how I define the beans in app2Context.xml.

<bean id="app2WebServiceTemplate" class="org.springframework.ws.client.core.WebServiceTemplate"> <property name="defaultUri" value="http://webservice-endpoint"> </property> <property name="marshaller"> <ref bean="castorMarshaller"></ref> </property> <property name="unmarshaller"> <ref bean="castorMarshaller"></ref> </property> </bean> <bean id="castorMarshaller" class="org.springframework.oxm.castor.CastorMarshaller"> <property name="mappingLocation" value="classpath:castorMapping.xml" /> </bean>

You can see I let CastorMarshaller to handle marshaling and unmarshaling, which I will talk about later.

Now I would show you how the code look like.

public App2Response app2m1(Param param) { App2Request request = new App2Request(param); App2Response response = app2WebServiceTemplate.marshalSendAndReceive(request, new Callback()); return response; } private class Callback implements WebServiceMessageCallback { @Override public void doWithMessage(WebServiceMessage message) throws IOException, TransformerException { SaajSoapMessage saajSoapMessage = (SaajSoapMessage)message; saajSoapMessage.getEnvelope().addNamespaceDeclaration(prefix, namespace); } }

You can see I create a WebServiceMessageCallback to handle the namespace, simply because I can't find a declarative way to get it into the SOAP XML request. If any of you know how, please let me know. Or you can confirm with me this is actually the right way to go.

This method is rather simple because I let CastorMarshaller mapping to do the heavy lifting.

Continue: How the Data Access Bean Look Like

Here is one of the data access bean.

package com.mycomp.app1.data; import java.sql.ResultSet; import java.sql.SQLException; import java.util.Collection; import org.springframework.jdbc.core.RowMapper; import org.springframework.jdbc.core.support.JdbcDaoSupport; public final class SimpleApp1ReaderImpl extends JdbcDaoSupport implements Appl1Reader { private static final String SELECT_SQL = "SELECT ..."; ... private final class App1Mapper implements RowMapper<App1DTO> { @Override public App1DTO mapRow(ResultSet rs, int row) throws SQLException { ... return new App1DTO(...); } } }

I always choose JdbcDaoSupport over Hibernate because I can have so much more control over what I want to do with the database.

Continue: How the Controllers Look Like

Here is one of the controllers.

package com.mycomp.app1.controllers; import java.util.Collection; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.stereotype.Controller; import org.springframework.web.bind.annotation.RequestBody; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RequestMethod; import org.springframework.web.bind.annotation.RequestParam; import org.springframework.web.bind.annotation.ResponseBody; import org.springframework.web.context.request.WebRequest; @Controller public class MyApp1Controller { private static final String SESSION_ATTRIBUTE_ABC = "ABC"; private MyApp1Service myApp1Service; @Autowired public void setMyApp1Service(MyApp1Service myApp1Service) { this.myApp1Service = myApp1Service; } @RequestMapping(value = "/myapp1m1.do", method = RequestMethod.GET, produces = "application/json; charset=utf-8") public @ResponseBody RequestBoxWrapper myapp1m1(WebRequest webRequest) { ... return myapp1(some, webRequest); } @RequestMapping(value = "/myapp1m1.do", method = RequestMethod.POST, consumes = "application/json; charset=utf-8", produces = "application/json; charset=utf-8") public @ResponseBody RequestBoxWrapper myapp1m1(@RequestBody Some some, WebRequest webRequest) { webRequest.setAttribute(SESSION_ATTRIBUTE_ABC, some, WebRequest.SCOPE_SESSION); ... return ...; } @RequestMapping(value = "/myapp1m2.do", method = RequestMethod.GET, produces = "application/json; charset=utf-8") public @ResponseBody ResponseBoxWrapper myapp1m2( @RequestParam("myparam") Param param, WebRequest webRequest) { Some some = (Some) webRequest.getAttribute( SESSION_ATTRIBUTE_ABC, WebRequest.SCOPE_SESSION); ... return ...; } } 

The myApp1Service matches the bean myApp1Service. Name matching is the most simple way of autowire.

Example: Spring-MVC Spring-JDBC Spring-WS CastorMarshaller and jQuery

This is a web application, which front end is all about jQuery, back end is Spring-MVC to provide JSON web services, and Spring-JDBC to access a relational database, and Spring-WS to access a remote SOAP web services, and CastorMarshaller to convert between Java POJO and SOAP XML.

It starts with a Maven pom.xml.

<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"> <modelversion>4.0.0</modelVersion> <groupid>myGroup</groupId> <artifactid>myApp</artifactId> <packaging>war</packaging> <version>1.0-SNAPSHOT</version> <name>My App Name</name> <url>http://www.mycomp.com/</url> <build> <finalname>myapp</finalName> </build> <repositories> <repository> <id>codehaus</id> <name>Maven Codehaus repository</name> <url>http://repository.codehaus.org/</url> </repository> </repositories> <properties> <spring.version>3.2.4.RELEASE</spring.version> <spring.ws.version>2.1.4.RELEASE</spring.ws.version> <jackson.version>1.9.13</jackson.version> <castor.version>1.2</castor.version> </properties> <dependencies> <dependency> <groupid>org.codehaus.castor</groupId> <artifactid>castor</artifactId> <version>${castor.version}</version> <exclusions> <exclusion> <artifactid>cglib-full</artifactId> <groupid>cglib</groupId> </exclusion> </exclusions> </dependency> <dependency> <groupid>org.codehaus.jackson</groupId> <artifactid>jackson-core-asl</artifactId> <version>${jackson.version}</version> <scope>runtime</scope> </dependency> <dependency> <groupid>org.codehaus.jackson</groupId> <artifactid>jackson-mapper-asl</artifactId> <version>${jackson.version}</version> <scope>runtime</scope> </dependency> <dependency> <groupid>org.springframework</groupId> <artifactid>spring-context</artifactId> <version>${spring.version}</version> <scope>runtime</scope> </dependency> <dependency> <groupid>org.springframework</groupId> <artifactid>spring-jdbc</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupid>org.springframework</groupId> <artifactid>spring-webmvc</artifactId> <version>${spring.version}</version> </dependency> <dependency> <groupid>org.springframework.ws</groupId> <artifactid>spring-ws-core</artifactId> <version>${spring.ws.version}</version> </dependency> </dependencies> </project>

The access to the relational database and the access to the remote SOAP web services are totally parallel so I don't want any cross point between them. I set up two source folders to hold them respectively but point both output folder to src/main/webapp/WEB-INF/classes.

Now it comes to the web.xml.

<?xml version="1.0" encoding="UTF-8"?> <web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" id="WebApp_ID" version="2.5"> <display-name>myAppName</display-name> <context-param> <param-name>contextConfigLocation</param-name> <param-value>classpath:app1Context.xml, classpath:app2Context.xml</param-value> </context-param> <listener> <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class> </listener> <servlet> <servlet-name>rest</servlet-name> <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class> <init-param> <param-name>contextConfigLocation</param-name> <param-value>/WEB-INF/rest-context.xml</param-value> </init-param> </servlet> <servlet-mapping> <servlet-name>rest</servlet-name> <url-pattern>*.do</url-pattern> </servlet-mapping> <welcome-file-list> <welcome-file>home.html</welcome-file> </welcome-file-list> </web-app>

As you can see, I use rest-context.xml to define the rest servlet.

<?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:oxm="http://www.springframework.org/schema/oxm" xmlns:util="http://www.springframework.org/schema/util" xmlns:mvc="http://www.springframework.org/schema/mvc" xmlns:context="http://www.springframework.org/schema/context" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-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/context http://www.springframework.org/schema/context/spring-context-3.0.xsd http://www.springframework.org/schema/oxm http://www.springframework.org/schema/oxm/spring-oxm-3.0.xsd http://www.springframework.org/schema/util http://www.springframework.org/schema/util/spring-util-3.0.xsd"> <!-- Enables automatic mapping of objects to and from JSON --> <mvc:annotation-driven /> <!-- Setup spring to pull in @Controller, @RequestMapping, etc Configuration scans specified packages for classes configured as Spring managed beans and automatically sets up objects annotated with @Controller, @Service etc. --> <context:component-scan base-package="com.mycomp.app1.controllers, com.mycomp.app2.controllers" /> </beans>

This rest xml is rather simple. It simply scans two controllers packages for @Controller. But I have defined in the web.xml to delegate all app1 related spring beans to app1Context.xml and app2 to app2Context.xml which sit right at their source folders respectively.

The app1Context.xml is for accessing the relational database.

<?xml version="1.0" encoding="UTF-8"?> <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" 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"> <context:annotation-config /> <bean id="myApp1Service" class="com.mycomp.app1.services.SimpleApp1ServiceImpl"> <property name="reader"> <ref bean="myApp1Reader"></ref> </property> </bean> <bean id="myApp1Reader" class="com.mycomp.app1.data.SimpleApp1ReaderImpl"> <property name="dataSource"> <ref bean="myApp1DataSource"></ref> </property> </bean> <bean id="myApp1DataSource" class="org.springframework.jndi.JndiObjectFactoryBean"> <property name="jndiName" value="java:/myApp1DS" /> </bean> </beans>

You will be wondering about where is the java:/myApp1DS. This comes to the JBoss JNDI datasource configuration. Create a xml file called myApp1-ds.xml.

<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE datasources PUBLIC "-//JBoss//DTD Datasource 1.5//EN" "http://www.jboss.org/j2ee/dtd/jboss-ds_1_5.dtd"> <datasources> <local-tx-datasource> <jndi-name>myApp1DS</jndi-name> <connection-url>jdbc:mysql://mydbserver:3306/mydbname </connection-url> <driver-class>com.mysql.jdbc.Driver</driver-class> <user-name>mydbuser</user-name> <password>mydbpassword</password> <exception-sorter-class-name>org.jboss.resource.adapter.jdbc.vendor.MySQLExceptionSorter </exception-sorter-class-name> <metadata> <type-mapping>mySQL</type-mapping> </metadata> </local-tx-datasource> </datasources>

You will of course first enable that JDBC driver on the JBoss, but it should be an easy walk for any JBoss guy. Then deploy the myApp1-ds.xml to the server/default/deploy folder. Remember this file name has to be -ds.xml. It rather makes JBoss look like a toy.

RESTClient to Test JSON Web Services

RESTClient is an add-on for Firefox. Once I was in a company that Firefox installation required special approval. This rule of approval alone was a prove that their CIO was below qualified.

When testing JSON web services, the only trick is to set the JSON request header.

Click on Headers and add Content-Type as name, application/json; charset=utf-8 as value.

Otherwise you will get HTTP Status 415.

Example: JBoss and LDAP

JBoss 5.1.0.GA.

1. Change directory to server/default/conf and edit login-config.xml
2. Add a new block of application-policy, I put it before the "other" application-policy.

<application-policy name="mycomp-ldap"> <authentication> <login-module code="org.jboss.security.auth.spi.LdapExtLoginModule" flag="required"> <module-option name="java.naming.factory.initial">com.sun.jndi.ldap.LdapCtxFactory</module-option> <module-option name="java.naming.provider.url">ldap://myldapserver:389/</module-option> <module-option name="java.naming.security.authentication">simple</module-option> <module-option name="bindDN"></module-option> <module-option name="bindCredential"></module-option> <module-option name="baseCtxDN">o=intra,dc=mycomp,dc=com</module-option> <module-option name="baseFilter">(uid={0})</module-option> <module-option name="rolesCtxDN">o=intra,dc=mycomp,dc=com</module-option> <module-option name="roleFilter">(uid={0})</module-option> <module-option name="roleAttributeID">nsRole</module-option> <module-option name="roleAttributeIsDN">false</module-option> <module-option name="roleRecursion">0</module-option> <module-option name="searchScope">SUBTREE_SCOPE</module-option> <module-option name="allowEmptyPasswords">true</module-option> <module-option name="defaultRole">cn=ldap-authenticated,o=intra,dc=mycomp,dc=com</module-option> </login-module> </authentication> </application-policy>

3.Under the WEB-INF directory, create jboss-web.xml and add a jboss-web definition.

<?xml version="1.0"?> <!DOCTYPE jboss-web PUBLIC "-//JBoss//DTD Web Application 5.0//EN" "http://www.jboss.org/j2ee/dtd/jboss-web_5_0.dtd"> <jboss-web> <security-domain>java:/jaas/mycomp-ldap</security-domain> <context-root>mycontext</context-root> </jboss-web>

4. Edit the web.xml file and add security configurations.

<security-constraint> <web-resource-collection> <web-resource-name>myapp</web-resource-name> <description>my description</description> <url-pattern>/*</url-pattern> </web-resource-collection> <auth-constraint> <description>Allowed only myrole users.</description> <role-name>cn=myrole,o=intra,dc=mycomp,dc=com</role-name> </auth-constraint> </security-constraint> <login-config> <auth-method>BASIC</auth-method> <realm-name>my realm</realm-name> </login-config> <security-role> <role-name>cn=myrole,o=intra,dc=mycomp,dc=com</role-name> </security-role>

5. It is nice to see what is happening behind the door, so I enable the trace in the JBoss logging configuration. Edit server/default/conf/jboss-log4j.xml.

<category name="org.jboss.security"> <priority value="TRACE"/> </category>

MyEclipse Enable Maven Dependencies in the Build Path

MyEclipse Enterprise Workbench

Version: 10.7

Of course, first disable the Maven4MyEclipse.

Then enable the WTP Deprecated. (as shown below).