| package freemarker.ext.jsp; |
| |
| import java.security.AccessController; |
| import java.security.PrivilegedAction; |
| |
| import javax.el.ELContext; |
| import javax.servlet.jsp.JspApplicationContext; |
| import javax.servlet.jsp.JspContext; |
| import javax.servlet.jsp.JspFactory; |
| import javax.servlet.jsp.PageContext; |
| import javax.servlet.jsp.el.ELException; |
| import javax.servlet.jsp.el.ExpressionEvaluator; |
| import javax.servlet.jsp.el.VariableResolver; |
| |
| import freemarker.log.Logger; |
| import freemarker.template.TemplateModelException; |
| |
| /** |
| * Don't use this class; it's only public to work around Google App Engine Java |
| * compliance issues. FreeMarker developers only: treat this class as package-visible. |
| * |
| * Implementation of PageContext that contains JSP 2.0 and JSP 2.1 specific |
| * methods. |
| * |
| * @author Attila Szegedi |
| */ |
| public class _FreeMarkerPageContext21 extends FreeMarkerPageContext { |
| private static final Logger logger = Logger.getLogger("freemarker.jsp"); |
| |
| static { |
| if(JspFactory.getDefaultFactory() == null) { |
| JspFactory.setDefaultFactory(new FreeMarkerJspFactory21()); |
| } |
| logger.debug("Using JspFactory implementation class " + |
| JspFactory.getDefaultFactory().getClass().getName()); |
| } |
| |
| public _FreeMarkerPageContext21() throws TemplateModelException { |
| super(); |
| } |
| |
| /** |
| * Attempts to locate and manufacture an expression evaulator instance. For this |
| * to work you <b>must</b> have the Apache Commons-EL package in the classpath. If |
| * Commons-EL is not available, this method will throw an UnsupportedOperationException. |
| */ |
| public ExpressionEvaluator getExpressionEvaluator() { |
| try { |
| Class type = ((ClassLoader)AccessController.doPrivileged( |
| new PrivilegedAction() { |
| public Object run() { |
| return Thread.currentThread().getContextClassLoader(); |
| } |
| })).loadClass |
| ("org.apache.commons.el.ExpressionEvaluatorImpl"); |
| return (ExpressionEvaluator) type.newInstance(); |
| } |
| catch (Exception e) { |
| throw new UnsupportedOperationException("In order for the getExpressionEvaluator() " + |
| "method to work, you must have downloaded the apache commons-el jar and " + |
| "made it available in the classpath."); |
| } |
| } |
| |
| /** |
| * Returns a variable resolver that will resolve variables by searching through |
| * the page scope, request scope, session scope and application scope for an |
| * attribute with a matching name. |
| */ |
| public VariableResolver getVariableResolver() { |
| final PageContext ctx = this; |
| |
| return new VariableResolver() { |
| public Object resolveVariable(String name) throws ELException { |
| return ctx.findAttribute(name); |
| } |
| }; |
| } |
| |
| private ELContext elContext; |
| |
| public ELContext getELContext() { |
| if(elContext == null) { |
| JspApplicationContext jspctx = JspFactory.getDefaultFactory().getJspApplicationContext(getServletContext()); |
| if(jspctx instanceof FreeMarkerJspApplicationContext) { |
| elContext = ((FreeMarkerJspApplicationContext)jspctx).createNewELContext(this); |
| elContext.putContext(JspContext.class, this); |
| } |
| else { |
| throw new UnsupportedOperationException( |
| "Can not create an ELContext using a foreign JspApplicationContext\n" + |
| "Consider dropping a private instance of JSP 2.1 API JAR file in\n" + |
| "your WEB-INF/lib directory and then try again."); |
| } |
| } |
| return elContext; |
| } |
| } |