[jboss-cvs] jboss-seam/src/main/org/jboss/seam/core ...

[Norman Richards]

  User: nrichards
  Date: 07/04/26 14:11:42

  Added:       src/main/org/jboss/seam/core  JBossELInstaller.java
  Log:
  add component to install enhanced EL
  
  Revision  Changes    Path
  1.1      date: 2007/04/26 18:11:42;  author: nrichards;  state: Exp;jboss-seam/src/main/org/jboss/seam/core/JBossELInstaller.java
  
  Index: JBossELInstaller.java
  ===================================================================
  package org.jboss.seam.core;
  
  import java.lang.reflect.Method;
  
  import javassist.util.proxy.MethodFilter;
  import javassist.util.proxy.MethodHandler;
  import javassist.util.proxy.ProxyFactory;
  import javax.servlet.jsp.JspApplicationContext;
  
  import org.jboss.el.ExpressionFactoryImpl;
  import org.jboss.seam.ScopeType;
  import org.jboss.seam.annotations.Create;
  import org.jboss.seam.annotations.Name;
  import org.jboss.seam.annotations.Scope;
  import org.jboss.seam.annotations.Startup;
  import org.jboss.seam.contexts.Context;
  import org.jboss.seam.contexts.Contexts;
  import org.jboss.seam.log.LogProvider;
  import org.jboss.seam.log.Logging;
  import org.jboss.seam.util.Reflections;
  
  @Name("org.jboss.seam.core.jbossELInstaller")
  @Startup
  @Scope(ScopeType.APPLICATION)
  public class JBossELInstaller {        
      private static final String TOMCAT_APPLICATION_CONTEXT = "org.apache.jasper.runtime.JspApplicationContextImpl";
      private static final String JSF_RI_ASSOCIATE = "com.sun.faces.ApplicationAssociate";
      
      private static final LogProvider log = Logging.getLogProvider(JBossELInstaller.class);
  
      @Create
      public void installJBossEL() {                   
          configureTomcatApplicationContext();
          configureRIAssociate();
      }
  
      /**
       * Set the default expression factory for the JSF RI     
       */
      public void configureRIAssociate() {        
          Object target = Contexts.getApplicationContext().get(JSF_RI_ASSOCIATE);
          if (target != null) {
              Method method = Reflections.getSetterMethod(target.getClass(), "expressionFactory");
              try {
                  method.invoke(target, new Object[] {new ExpressionFactoryImpl()});  
                  log.debug("set expression factory on RI associate");
              } catch (Exception e) {
                  log.error("couldn't set expression factory on RI associate", e);
              }
          }
      }
  
      /**
       * Set the expression factory for the tomcat JSPApplicationContext associated with this deployment.
       * This works, but the use EL enhancements in JSPs will be rejected by tomcat as invalid.  
       */
      public void configureTomcatApplicationContext() {
          Context appContext = Contexts.getApplicationContext();
          JspApplicationContext target = (JspApplicationContext)appContext.get(TOMCAT_APPLICATION_CONTEXT);
          if (target != null) {
              ProxyFactory factory = new ProxyFactory();
              factory.setSuperclass( target.getClass());
              factory.setFilter(new MethodFilter() {
                  public boolean isHandled(Method method) {
                      return method.getName().equals("getExpressionFactory");
                  }                
              });
              factory.setHandler(new MethodHandler() {
                  public Object invoke(Object arg0, Method arg1, Method arg2, Object[] arg3) throws Throwable {
                      return new ExpressionFactoryImpl();
                  }
              });
  
              try {
                  target = (JspApplicationContext) factory.create(new Class[0], new Object[0]);
  
                  appContext.set(TOMCAT_APPLICATION_CONTEXT, target);
                  log.debug("replaced tomcat application context");
              } catch (Exception e ) {
                  log.error("couldn't replace tomcat application context", e);
              }
          }
      }
  
  }