/*
* $Id: JavaScriptExpression.java 385057 2006-03-11 10:57:03Z bruno $
*
* Created on 2005-10-17
*
* Copyright (c) 2005, MobileBox sp. z o.o.
* All rights reserved.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
package org.apache.cocoon.components.expression.javascript;
import java.util.Iterator;
import java.util.Map;
import java.io.StringReader;
import org.apache.cocoon.components.expression.AbstractExpression;
import org.apache.cocoon.components.expression.ExpressionContext;
import org.apache.cocoon.components.expression.ExpressionException;
import org.apache.cocoon.components.expression.jexl.JSIntrospector;
import org.apache.cocoon.components.flow.FlowHelper;
import org.apache.cocoon.environment.TemplateObjectModelHelper;
import org.apache.commons.jexl.util.introspection.Info;
import org.mozilla.javascript.Context;
import org.mozilla.javascript.Script;
import org.mozilla.javascript.Scriptable;
public class JavaScriptExpression extends AbstractExpression {
private Script script;
private JSIntrospector introspector;
public JavaScriptExpression(String language, String expression) {
super(language, expression);
compile();
}
private void compile() {
Context ctx = Context.enter();
try {
// Note: used compileReader instead of compileString to work with the older Rhino in C2.1
this.script = ctx.compileReader(TemplateObjectModelHelper.getScope(), new StringReader(getExpression()), "", 1, null);
} catch (Exception e) {
// Note: this catch block is only needed for the Rhino in C2.1 where the older
// Rhino does not throw RuntimeExceptions
if (e instanceof RuntimeException)
throw (RuntimeException)e;
else
throw new RuntimeException(e);
} finally {
Context.exit();
}
}
public Object evaluate(ExpressionContext context) throws ExpressionException {
Context ctx = Context.enter();
try {
Scriptable scope = ctx.newObject(TemplateObjectModelHelper.getScope());
// Populate the scope
Iterator iter = context.entrySet().iterator();
while (iter.hasNext()) {
Map.Entry entry = (Map.Entry) iter.next();
String key = (String) entry.getKey();
Object value = entry.getValue();
scope.put(key, scope, Context.toObject(value, scope));
}
Object result = this.script.exec(ctx, scope);
return FlowHelper.unwrap(result);
} catch (Exception e) {
// Note: this catch block is only needed for the Rhino in C2.1 where the older
// Rhino does not throw RuntimeExceptions
if (e instanceof RuntimeException)
throw (RuntimeException)e;
else
throw new RuntimeException(e);
} finally {
Context.exit();
}
}
public Iterator iterate(ExpressionContext context) throws ExpressionException {
Object result = evaluate(context);
if (result == null)
return EMPTY_ITER;
if (this.introspector == null)
introspector = new JSIntrospector();
Iterator iter = null;
try {
iter = introspector.getIterator(result, new Info("Unknown", 0, 0));
} catch (Exception e) {
throw new ExpressionException("Couldn't get an iterator from expression " + getExpression(), e);
}
if (iter == null)
iter = EMPTY_ITER;
return iter;
}
public void assign(ExpressionContext context, Object value) throws ExpressionException {
throw new UnsupportedOperationException("assignment not implemented for javascript expressions");
}
public Object getNode(ExpressionContext context) throws ExpressionException {
return evaluate(context);
}
}