FileDocCategorySizeDatePackage
BeanSelectionProvider.javaAPI DocExample10883Mon Jul 23 13:26:54 BST 2007org.apache.struts2.config

BeanSelectionProvider

public class BeanSelectionProvider extends Object implements com.opensymphony.xwork2.config.ConfigurationProvider
Selects the implementations of key framework extension points, using the loaded property constants. The implementations are selected from the container builder using the name defined in its associated property. The default implementation name will always be "struts".

The following is a list of the allowed extension points:
Type Property Scope Description
com.opensymphony.xwork2.ObjectFactory struts.objectFactory singleton Creates actions, results, and interceptors
com.opensymphony.xwork2.ActionProxyFactory struts.actionProxyFactory singleton Creates the ActionProxy
com.opensymphony.xwork2.util.ObjectTypeDeterminer struts.objectTypeDeterminer singleton Determines what the key and and element class of a Map or Collection should be
org.apache.struts2.dispatcher.mapper.ActionMapper struts.mapper.class singleton Determines the ActionMapping from a request and a URI from an ActionMapping
org.apache.struts2.dispatcher.multipart.MultiPartRequest struts.multipart.parser per request Parses a multipart request (file upload)
org.apache.struts2.views.freemarker.FreemarkerManager struts.freemarker.manager.classname singleton Loads and processes Freemarker templates
org.apache.struts2.views.velocity.VelocityManager struts.velocity.manager.classname singleton Loads and processes Velocity templates

Implementations are selected using the value of its associated property. That property is used to determine the implementation by:

  1. Trying to find an existing bean by that name in the container
  2. Trying to find a class by that name, then creating a new bean factory for it
  3. Creating a new delegation bean factory that delegates to the configured ObjectFactory at runtime

Finally, this class overrides certain properties if dev mode is enabled:

  • struts.i18n.reload = true
  • struts.configuration.xml.reload = true

Fields Summary
public static final String
DEFAULT_BEAN_NAME
private static final Log
LOG
Constructors Summary
Methods Summary
voidalias(java.lang.Class type, java.lang.String key, com.opensymphony.xwork2.inject.ContainerBuilder builder, java.util.Properties props)

        alias(type, key, builder, props, Scope.SINGLETON);
voidalias(java.lang.Class type, java.lang.String key, com.opensymphony.xwork2.inject.ContainerBuilder builder, java.util.Properties props, com.opensymphony.xwork2.inject.Scope scope)

        if (!builder.contains(type)) {
            String foundName = props.getProperty(key, DEFAULT_BEAN_NAME);
            if (builder.contains(type, foundName)) {
                if (LOG.isDebugEnabled()) {
                    LOG.info("Choosing bean ("+foundName+") for "+type);
                }
                builder.alias(type, foundName, Container.DEFAULT_NAME);
            } else {
                try {
                    Class cls = ClassLoaderUtil.loadClass(foundName, this.getClass());
                    if (LOG.isDebugEnabled()) {
                        LOG.debug("Choosing bean ("+cls+") for "+type);
                    }
                    builder.factory(type, cls, scope);
                } catch (ClassNotFoundException ex) {
                    // Perhaps a spring bean id, so we'll delegate to the object factory at runtime
                    if (LOG.isDebugEnabled()) {
                        LOG.debug("Choosing bean ("+foundName+") for "+type+" to be loaded from the ObjectFactory");
                    }
                    if (DEFAULT_BEAN_NAME.equals(foundName)) {
                        // Probably an optional bean, will ignore
                    } else {
                        if (ObjectFactory.class != type) {
                            builder.factory(type, new ObjectFactoryDelegateFactory(foundName, type), scope);
                        } else {
                            throw new ConfigurationException("Cannot locate the chosen ObjectFactory implementation: "+foundName);
                        }
                    }
                }
            }
        } else {
            LOG.warn("Unable to alias bean type "+type+", default mapping already assigned.");
        }
public voiddestroy()

    
       
        // NO-OP
public voidinit(com.opensymphony.xwork2.config.Configuration configuration)

        // NO-OP
public voidloadPackages()

        // NO-OP
public booleanneedsReload()

        return false;
public voidregister(com.opensymphony.xwork2.inject.ContainerBuilder builder, com.opensymphony.xwork2.util.location.LocatableProperties props)

        alias(ObjectFactory.class, StrutsConstants.STRUTS_OBJECTFACTORY, builder, props);
        alias(XWorkConverter.class, StrutsConstants.STRUTS_XWORKCONVERTER, builder, props);
        alias(TextProvider.class, StrutsConstants.STRUTS_XWORKTEXTPROVIDER, builder, props);
        alias(ActionProxyFactory.class, StrutsConstants.STRUTS_ACTIONPROXYFACTORY, builder, props);
        alias(ObjectTypeDeterminer.class, StrutsConstants.STRUTS_OBJECTTYPEDETERMINER, builder, props);
        alias(ActionMapper.class, StrutsConstants.STRUTS_MAPPER_CLASS, builder, props);
        alias(MultiPartRequest.class, StrutsConstants.STRUTS_MULTIPART_PARSER, builder, props, Scope.DEFAULT);
        alias(FreemarkerManager.class, StrutsConstants.STRUTS_FREEMARKER_MANAGER_CLASSNAME, builder, props);
        alias(VelocityManager.class, StrutsConstants.STRUTS_VELOCITY_MANAGER_CLASSNAME, builder, props);
        
        if ("true".equalsIgnoreCase(props.getProperty(StrutsConstants.STRUTS_DEVMODE))) {
            props.setProperty(StrutsConstants.STRUTS_I18N_RELOAD, "true");
            props.setProperty(StrutsConstants.STRUTS_CONFIGURATION_XML_RELOAD, "true");
            // Convert struts properties into ones that xwork expects
            props.setProperty("devMode", "true");
        } else {
            props.setProperty("devMode", "false");
        }
        
        // TODO: This should be moved to XWork after 2.0.4
        // struts.custom.i18n.resources

        LocalizedTextUtil.addDefaultResourceBundle("org/apache/struts2/struts-messages");
        
        String bundles = props.getProperty(StrutsConstants.STRUTS_CUSTOM_I18N_RESOURCES);
        if (bundles != null && bundles.length() > 0) { 
            StringTokenizer customBundles = new StringTokenizer(props.getProperty(StrutsConstants.STRUTS_CUSTOM_I18N_RESOURCES), ", ");
            
            while (customBundles.hasMoreTokens()) {
                String name = customBundles.nextToken();
                try {
                    LOG.info("Loading global messages from " + name);
                    LocalizedTextUtil.addDefaultResourceBundle(name);
                } catch (Exception e) {
                    LOG.error("Could not find messages file " + name + ".properties. Skipping");
                }
            } 
        }