com.google.gwt.uibinder.attributeparsers.SafeUriAttributeParser Maven / Gradle / Ivy
/*
* Copyright 2011 Google Inc.
*
* 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 com.google.gwt.uibinder.attributeparsers;
import com.google.gwt.core.ext.UnableToCompleteException;
import com.google.gwt.core.ext.typeinfo.JType;
import com.google.gwt.uibinder.rebind.MortalLogger;
import com.google.gwt.uibinder.rebind.XMLElement;
/**
* Parses {@link com.google.gwt.safehtml.shared.SafeUri SafeUri} literals or
* references.
*
* Simple String literals are passed through
* {@link com.google.gwt.safehtml.shared.UriUtils#fromConstantString(String)
* UriUtils.fromConstantString(String)}
*
* Accepts concatenated string expressions, mainly for compatibility with legacy
* <a href="{foo.bar}{baz.bang}"> abuses. Passes such nonsense
* through {@link com.google.gwt.safehtml.shared.UriUtils#fromString(String)
* UriUtils.fromString(String)}
*/
public class SafeUriAttributeParser extends StrictAttributeParser {
public static String wrapUnsafeStringAndWarn(MortalLogger logger, XMLElement source,
String expression) {
logger.warn(source, "Escaping unsafe runtime String expression "
+ "used for URI with UriUtils.fromString(). Use SafeUri instead");
return "UriUtils.fromString(" + expression + ")";
}
private final boolean runtimeStringsAllowed;
private final StringAttributeParser stringParser;
/**
* Constructs an instance for particular use in html contexts, where
* {string.references} are acceptible.
*/
SafeUriAttributeParser(StringAttributeParser stringParser, FieldReferenceConverter converter,
JType safeUriType, JType stringType, MortalLogger logger) {
super(converter, logger, safeUriType, stringType);
this.stringParser = stringParser;
runtimeStringsAllowed = true;
}
/**
* Constructs an instance for normal use, where String literals are okay but
* {string.references} are not.
*/
SafeUriAttributeParser(StringAttributeParser stringParser, FieldReferenceConverter converter,
JType safeUriType, MortalLogger logger) {
super(converter, logger, safeUriType);
this.stringParser = stringParser;
runtimeStringsAllowed = false;
}
@Override
public String parse(XMLElement source, String value) throws UnableToCompleteException {
int howManyFieldRefs = FieldReferenceConverter.countFieldReferences(value);
/*
* No field refs, just a string literal.
*
* Isn't this a lot of pointless codegen for ? No. In
* such an html context this parser is called only for computed attributes,
* where howManyFieldRefs is > 0. See
* HtmlInterpreter#ComputedAttributeTypist
*/
if (howManyFieldRefs == 0) {
// String literal, convert it for the nice people
return "UriUtils.fromSafeConstant(" + stringParser.parse(source, value) + ")";
}
/*
* No runtime string expressions are allowed, or they are but it
* "{looks.like.this}". Just do the usual parsing.
*/
if (!runtimeStringsAllowed || howManyFieldRefs == 1 && value.substring(0, 1).equals("{")
&& value.substring(value.length() - 1, value.length()).equals("}")) {
return super.parse(source, value);
}
return wrapUnsafeStringAndWarn(logger, source, stringParser.parse(source, value));
}
}