org.apache.jasper.compiler.Collector Maven / Gradle / Ivy
/*
* Copyright (c) 1997, 2018 Oracle and/or its affiliates. All rights reserved.
* Copyright 2004 The Apache Software Foundation
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.jasper.compiler;
import org.apache.jasper.JasperException;
/**
* Collect info about the page and nodes, and make them availabe through
* the PageInfo object.
*
* @author Kin-man Chung
* @author Mark Roth
*/
class Collector {
/**
* A visitor for collecting information on the page and the body of
* the custom tags.
*/
static class CollectVisitor extends Node.Visitor {
private int maxTagNesting = 0;
private int curTagNesting = 0;
private boolean scriptingElementSeen = false;
private boolean usebeanSeen = false;
private boolean includeActionSeen = false;
private boolean paramActionSeen = false;
private boolean setPropertySeen = false;
private boolean hasScriptingVars = false;
public void visit(Node.ParamAction n) throws JasperException {
if (n.getValue().isExpression()) {
scriptingElementSeen = true;
}
paramActionSeen = true;
}
public void visit(Node.IncludeAction n) throws JasperException {
if (n.getPage().isExpression()) {
scriptingElementSeen = true;
}
includeActionSeen = true;
visitBody(n);
}
public void visit(Node.ForwardAction n) throws JasperException {
if (n.getPage().isExpression()) {
scriptingElementSeen = true;
}
visitBody(n);
}
public void visit(Node.SetProperty n) throws JasperException {
if (n.getValue() != null && n.getValue().isExpression()) {
scriptingElementSeen = true;
}
setPropertySeen = true;
}
public void visit(Node.UseBean n) throws JasperException {
if (n.getBeanName() != null && n.getBeanName().isExpression()) {
scriptingElementSeen = true;
}
usebeanSeen = true;
visitBody(n);
}
public void visit(Node.PlugIn n) throws JasperException {
if (n.getHeight() != null && n.getHeight().isExpression()) {
scriptingElementSeen = true;
}
if (n.getWidth() != null && n.getWidth().isExpression()) {
scriptingElementSeen = true;
}
visitBody(n);
}
public void visit(Node.CustomTag n) throws JasperException {
curTagNesting++;
if (curTagNesting > maxTagNesting) {
maxTagNesting = curTagNesting;
}
// Check to see what kinds of element we see as child elements
checkSeen( n.getChildInfo(), n );
curTagNesting--;
}
/**
* Check all child nodes for various elements and update the given
* ChildInfo object accordingly. Visits body in the process.
*/
private void checkSeen( Node.ChildInfo ci, Node n )
throws JasperException
{
// save values collected so far
boolean scriptingElementSeenSave = scriptingElementSeen;
scriptingElementSeen = false;
boolean usebeanSeenSave = usebeanSeen;
usebeanSeen = false;
boolean includeActionSeenSave = includeActionSeen;
includeActionSeen = false;
boolean paramActionSeenSave = paramActionSeen;
paramActionSeen = false;
boolean setPropertySeenSave = setPropertySeen;
setPropertySeen = false;
boolean hasScriptingVarsSave = hasScriptingVars;
hasScriptingVars = false;
// Scan attribute list for expressions
if( n instanceof Node.CustomTag ) {
Node.CustomTag ct = (Node.CustomTag)n;
Node.JspAttribute[] attrs = ct.getJspAttributes();
for (int i = 0; attrs != null && i < attrs.length; i++) {
if (attrs[i].isExpression()) {
scriptingElementSeen = true;
break;
}
}
}
visitBody(n);
if( (n instanceof Node.CustomTag) && !hasScriptingVars) {
Node.CustomTag ct = (Node.CustomTag)n;
hasScriptingVars = ct.getVariableInfos().length > 0 ||
ct.getTagVariableInfos().length > 0;
}
// Record if the tag element and its body contains any scriptlet.
ci.setScriptless(! scriptingElementSeen);
ci.setHasUseBean(usebeanSeen);
ci.setHasIncludeAction(includeActionSeen);
ci.setHasParamAction(paramActionSeen);
ci.setHasSetProperty(setPropertySeen);
ci.setHasScriptingVars(hasScriptingVars);
// Propagate value of scriptingElementSeen up.
scriptingElementSeen = scriptingElementSeen || scriptingElementSeenSave;
usebeanSeen = usebeanSeen || usebeanSeenSave;
setPropertySeen = setPropertySeen || setPropertySeenSave;
includeActionSeen = includeActionSeen || includeActionSeenSave;
paramActionSeen = paramActionSeen || paramActionSeenSave;
hasScriptingVars = hasScriptingVars || hasScriptingVarsSave;
}
public void visit(Node.JspElement n) throws JasperException {
if (n.getNameAttribute().isExpression())
scriptingElementSeen = true;
Node.JspAttribute[] attrs = n.getJspAttributes();
for (int i = 0; i < attrs.length; i++) {
if (attrs[i].isExpression()) {
scriptingElementSeen = true;
break;
}
}
visitBody(n);
}
public void visit(Node.JspBody n) throws JasperException {
checkSeen( n.getChildInfo(), n );
}
public void visit(Node.NamedAttribute n) throws JasperException {
checkSeen( n.getChildInfo(), n );
}
public void visit(Node.Declaration n) throws JasperException {
scriptingElementSeen = true;
}
public void visit(Node.Expression n) throws JasperException {
scriptingElementSeen = true;
}
public void visit(Node.Scriptlet n) throws JasperException {
scriptingElementSeen = true;
}
public void updatePageInfo(PageInfo pageInfo) {
pageInfo.setMaxTagNesting(maxTagNesting);
pageInfo.setScriptless(! scriptingElementSeen);
}
}
public static void collect(Compiler compiler, Node.Nodes page)
throws JasperException {
CollectVisitor collectVisitor = new CollectVisitor();
page.visit(collectVisitor);
collectVisitor.updatePageInfo(compiler.getPageInfo());
}
}