Using Expression Language

This is an example using expression language in Java



import javax.el.ValueExpression;

import junit.framework.Assert;
import junit.framework.TestCase;

import org.jlego.core.Dto;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import de.odysseus.el.util.SimpleContext;

public class TestExpression extends TestCase {

private static final Logger log = LoggerFactory.getLogger(TestExpression.class);

public void testJuel(){
java.util.Properties properties = new java.util.Properties();
properties.put("javax.el.cacheSize", "5000");
javax.el.ExpressionFactory factory = new de.odysseus.el.ExpressionFactoryImpl(properties);

Map map= new HashMap();
map .put("data", "ali");

SimpleContext context = new SimpleContext();
context.setVariable("request", factory.createValueExpression(map, HashMap.class));
ValueExpression expr = factory.createValueExpression(context, "${request.data == 'ali'}", Object.class);

Assert.assertEquals("true", expr.getValue(context).toString());

ValueExpression expr2 = factory.createValueExpression(context, "${ (1==0) ? 'ali' : ((2==2) ? 'not not ali' : 'not ali') }", Object.class);

Assert.assertEquals("not not ali",expr2.getValue(context));
}
}

I'm using Maven, so make sure you have these dependencies:


<dependency>
<groupId>de.odysseus.juel</groupId>
<artifactId>juel</artifactId>
<version>2.1.3</version>
</dependency>

Of course JUnit as well


<dependency>
        <groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.8.1</version>
<scope>test</scope>
</dependency>