Using Seam EL outside a web application

[awestwel]

Good Afternoon

I am attempting to use Seam's EL in a standalone application (Non web). I have taken a sample from a blog at following blog http://weblogs.java.net/blog/felipeal/archive/2008/10/adding_el_suppo.html as a starting point. I tried to modify it and use Seams EL API without success.

Anyone care to comment on what I am doing wrong?

I am getting the following exception

javax.el.ELException: Provider org.jboss.seam.el.SeamExpressionFactory could not be instantiated: java.lang.InstantiationException: org.jboss.seam.el.SeamExpressionFactory
     at javax.el.FactoryFinder.newInstance(FactoryFinder.java:69)
     at javax.el.FactoryFinder.find(FactoryFinder.java:152)
     at javax.el.ExpressionFactory.newInstance(ExpressionFactory.java:154)
     at javax.el.ExpressionFactory.newInstance(ExpressionFactory.java:125)
     at com.sandvine.commons.el.test.BlogTest.<clinit>(BlogTest.java:38)
     at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
     at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:39)
     at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:27)
     at java.lang.reflect.Constructor.newInstance(Constructor.java:494)
     at junit.framework.TestSuite.createTest(TestSuite.java:61)
     at junit.framework.TestSuite.addTestMethod(TestSuite.java:283)
     at junit.framework.TestSuite.<init>(TestSuite.java:146)
     at org.junit.internal.runners.JUnit38ClassRunner.<init>(JUnit38ClassRunner.java:67)
     at org.junit.internal.builders.JUnit3Builder.runnerForClass(JUnit3Builder.java:14)
     at org.junit.runners.model.RunnerBuilder.safeRunnerForClass(RunnerBuilder.java:57)
     at org.junit.internal.builders.AllDefaultPossibilitiesBuilder.runnerForClass(AllDefaultPossibilitiesBuilder.java:29)
     at org.junit.runners.model.RunnerBuilder.safeRunnerForClass(RunnerBuilder.java:57)
     at org.junit.internal.requests.ClassRequest.getRunner(ClassRequest.java:24)
     at org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.<init>(JUnit4TestReference.java:26)
     at org.eclipse.jdt.internal.junit4.runner.JUnit4TestClassReference.<init>(JUnit4TestClassReference.java:24)
     at org.eclipse.jdt.internal.junit4.runner.JUnit4TestLoader.createTest(JUnit4TestLoader.java:40)
     at org.eclipse.jdt.internal.junit4.runner.JUnit4TestLoader.loadTests(JUnit4TestLoader.java:30)
     at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:445)
     at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests(RemoteTestRunner.java:673)
     at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run(RemoteTestRunner.java:386)
     at org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main(RemoteTestRunner.java:196)
Caused by: java.lang.InstantiationException: org.jboss.seam.el.SeamExpressionFactory
     at java.lang.Class.newInstance0(Class.java:335)
     at java.lang.Class.newInstance(Class.java:303)
     at javax.el.FactoryFinder.newInstance(FactoryFinder.java:64)
     ... 25 more


BlogTest.java

package test;

import javax.el.ExpressionFactory;
import javax.el.ValueExpression;

import junit.framework.TestCase;
import org.jboss.seam.el.SeamExpressionFactory;

public class BlogTest extends TestCase {

     public void testDoItdoIt() {
          String elText = "Dude, where is my ${car}?";
          SampleContext context = new SampleContext();
          context.bind("car", "EL tutorial");
          Object convertedText = doSomeMagic(context, elText);
          assertEquals("Dude, where is my EL tutorial?", (String) convertedText);
     }

     private Object doSomeMagic(SampleContext context, String elText) {
          if (factory == null) {
               throw new RuntimeException(
                         "could not get instance of factory class " + factoryClass);
          }
          ValueExpression converted = factory.createValueExpression(context,
                    elText, Object.class);
          return converted.getValue(context);
     }

     //private static final String factoryClass = "org.apache.el.ExpressionFactoryImpl";
     private static final String factoryClass = "org.jboss.seam.el.SeamExpressionFactory";
     private static final ExpressionFactory factory;

     static {
          System.setProperty("javax.el.ExpressionFactory", factoryClass);
          ExpressionFactory tmpFactory = null;
          try {
               tmpFactory = ExpressionFactory.newInstance();
          } catch (RuntimeException e) {
               e.printStackTrace();
               System.out.println(e.getMessage());
          }
          factory = tmpFactory;
     }

}


SampleContext.jav


package test;

import java.lang.reflect.Method;
import java.util.HashMap;
import java.util.Map;

import javax.el.BeanELResolver;
import javax.el.ELContext;
import javax.el.ELResolver;
import javax.el.FunctionMapper;
import javax.el.ValueExpression;
import javax.el.VariableMapper;

import org.jboss.el.ValueExpressionLiteral;

public class SampleContext extends ELContext {

     private final BeanELResolver resolver = new BeanELResolver();
     private final FunctionMapper functionMapper = new NoopFunctionMapper();
     private final VariableMapper variableMapper = new VariableMapperImpl();
     private final Map variables = new HashMap();

     @Override
     public ELResolver getELResolver() {
          return resolver;
     }

     @Override
     public FunctionMapper getFunctionMapper() {
          return functionMapper;
     }

     @Override
     public VariableMapper getVariableMapper() {
          return variableMapper;
     }

     public void bind(String variable, Object obj) {
          variables.put(variable, new ValueExpressionLiteral(obj,
                    Object.class));
     }

     private class VariableMapperImpl extends VariableMapper {
          
          public ValueExpression resolveVariable(String s) {
               return (ValueExpression) variables.get(s);
          }

          public ValueExpression setVariable(String s, ValueExpression valueExpression) {
               return (ValueExpression) (variables.put(s, valueExpression));
          }
     }

     private class NoopFunctionMapper extends FunctionMapper {
          public Method resolveFunction(String s, String s1) {
               return null;
          }
     }

}