| package freemarker.ext.rhino; |
| |
| import java.security.AccessController; |
| import java.security.PrivilegedExceptionAction; |
| |
| import org.mozilla.javascript.Scriptable; |
| import org.mozilla.javascript.Undefined; |
| import org.mozilla.javascript.UniqueTag; |
| import org.mozilla.javascript.Wrapper; |
| |
| import freemarker.ext.beans.BeansWrapper; |
| import freemarker.ext.util.ModelFactory; |
| import freemarker.template.TemplateModel; |
| import freemarker.template.TemplateModelException; |
| import freemarker.template.utility.UndeclaredThrowableException; |
| |
| /** |
| * @author Attila Szegedi |
| */ |
| public class RhinoWrapper extends BeansWrapper { |
| // The type of the "instance" field changed between Rhino versions, so a |
| // GETSTATIC with wrong type declaration would cause a NoSuchFieldError; |
| // we're avoiding it by acquiring it reflectively. |
| private static final Object UNDEFINED_INSTANCE; |
| static { |
| try { |
| UNDEFINED_INSTANCE = AccessController.doPrivileged(new PrivilegedExceptionAction() { |
| public Object run() throws Exception { |
| return Undefined.class.getField("instance").get(null); |
| } |
| }); |
| } |
| catch(RuntimeException e) { |
| throw e; |
| } |
| catch(Exception e) { |
| throw new UndeclaredThrowableException(e); |
| } |
| } |
| |
| public TemplateModel wrap(Object obj) throws TemplateModelException { |
| // So our existence builtins work as expected. |
| if(obj == UNDEFINED_INSTANCE || obj == UniqueTag.NOT_FOUND) { |
| return null; |
| } |
| // UniqueTag.NULL_VALUE represents intentionally set null in Rhino, and |
| // BeansWrapper#nullModel also represents intentionally returned null. |
| // I [A.Sz.] am fairly certain that this value is never passed out of |
| // any of the Rhino code back to clients, but is instead always being |
| // converted back to null. However, since this object is available to |
| // any 3rd party Scriptable implementations as well, they might return |
| // it, so we'll just be on the safe side, and handle it. |
| if(obj == UniqueTag.NULL_VALUE) { |
| return super.wrap(null); |
| } |
| // So, say, a JavaAdapter for FreeMarker interfaces works |
| if(obj instanceof Wrapper) { |
| obj = ((Wrapper)obj).unwrap(); |
| } |
| return super.wrap(obj); |
| } |
| |
| protected ModelFactory getModelFactory(Class clazz) { |
| if(Scriptable.class.isAssignableFrom(clazz)) { |
| return RhinoScriptableModel.FACTORY; |
| } |
| return super.getModelFactory(clazz); |
| } |
| } |