| /* |
| * Copyright 2008 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.resources.css; |
| |
| import com.google.gwt.core.ext.TreeLogger; |
| import com.google.gwt.core.ext.UnableToCompleteException; |
| import com.google.gwt.core.shared.impl.StringCase; |
| import com.google.gwt.resources.css.ast.CssDef; |
| import com.google.gwt.resources.css.ast.CssEval; |
| import com.google.gwt.resources.css.ast.CssExternalSelectors; |
| import com.google.gwt.resources.css.ast.CssFontFace; |
| import com.google.gwt.resources.css.ast.CssIf; |
| import com.google.gwt.resources.css.ast.CssMediaRule; |
| import com.google.gwt.resources.css.ast.CssNoFlip; |
| import com.google.gwt.resources.css.ast.CssNode; |
| import com.google.gwt.resources.css.ast.CssPageRule; |
| import com.google.gwt.resources.css.ast.CssProperty; |
| import com.google.gwt.resources.css.ast.CssProperty.DotPathValue; |
| import com.google.gwt.resources.css.ast.CssProperty.FunctionValue; |
| import com.google.gwt.resources.css.ast.CssProperty.IdentValue; |
| import com.google.gwt.resources.css.ast.CssProperty.ListValue; |
| import com.google.gwt.resources.css.ast.CssProperty.NumberValue; |
| import com.google.gwt.resources.css.ast.CssProperty.StringValue; |
| import com.google.gwt.resources.css.ast.CssProperty.TokenValue; |
| import com.google.gwt.resources.css.ast.CssProperty.Value; |
| import com.google.gwt.resources.css.ast.CssRule; |
| import com.google.gwt.resources.css.ast.CssSelector; |
| import com.google.gwt.resources.css.ast.CssSprite; |
| import com.google.gwt.resources.css.ast.CssStylesheet; |
| import com.google.gwt.resources.css.ast.CssUnknownAtRule; |
| import com.google.gwt.resources.css.ast.CssUrl; |
| import com.google.gwt.resources.css.ast.HasNodes; |
| import com.google.gwt.resources.css.ast.HasProperties; |
| import com.google.gwt.resources.ext.ResourceGeneratorUtil; |
| |
| import org.w3c.css.sac.AttributeCondition; |
| import org.w3c.css.sac.CSSException; |
| import org.w3c.css.sac.CSSParseException; |
| import org.w3c.css.sac.CharacterDataSelector; |
| import org.w3c.css.sac.CombinatorCondition; |
| import org.w3c.css.sac.Condition; |
| import org.w3c.css.sac.ConditionalSelector; |
| import org.w3c.css.sac.ContentCondition; |
| import org.w3c.css.sac.DescendantSelector; |
| import org.w3c.css.sac.DocumentHandler; |
| import org.w3c.css.sac.ElementSelector; |
| import org.w3c.css.sac.ErrorHandler; |
| import org.w3c.css.sac.InputSource; |
| import org.w3c.css.sac.LangCondition; |
| import org.w3c.css.sac.LexicalUnit; |
| import org.w3c.css.sac.NegativeCondition; |
| import org.w3c.css.sac.NegativeSelector; |
| import org.w3c.css.sac.PositionalCondition; |
| import org.w3c.css.sac.ProcessingInstructionSelector; |
| import org.w3c.css.sac.SACMediaList; |
| import org.w3c.css.sac.Selector; |
| import org.w3c.css.sac.SelectorList; |
| import org.w3c.css.sac.SiblingSelector; |
| import org.w3c.flute.parser.Parser; |
| |
| import java.io.IOException; |
| import java.io.StringReader; |
| import java.lang.ref.SoftReference; |
| import java.lang.reflect.InvocationTargetException; |
| import java.lang.reflect.Method; |
| import java.net.URISyntaxException; |
| import java.net.URL; |
| import java.util.ArrayList; |
| import java.util.Arrays; |
| import java.util.Collections; |
| import java.util.HashMap; |
| import java.util.Iterator; |
| import java.util.List; |
| import java.util.ListIterator; |
| import java.util.Map; |
| import java.util.Stack; |
| import java.util.regex.Matcher; |
| import java.util.regex.Pattern; |
| |
| /** |
| * Generates a CssStylesheet from the contents of a URL. |
| */ |
| @SuppressWarnings("unused") |
| public class GenerateCssAst { |
| |
| /** |
| * Maps SAC CSSParseExceptions into a TreeLogger. All parsing errors will be |
| * recorded in a single TreeLogger branch, which will be created only if a |
| * loggable error message is emitted. |
| */ |
| private static class Errors implements ErrorHandler { |
| /** |
| * A flag that controls whether or not the exec method will fail. |
| */ |
| private boolean fatalErrorEncountered; |
| private TreeLogger logger; |
| private final TreeLogger parentLogger; |
| |
| /** |
| * Constructor. |
| * |
| * @param parentLogger the TreeLogger that should be branched to produce the |
| * CSS parsing messages. |
| */ |
| public Errors(TreeLogger parentLogger) { |
| this.parentLogger = parentLogger; |
| } |
| |
| public TreeLogger branch(TreeLogger.Type type, String message) { |
| return branch(type, message, null); |
| } |
| |
| public TreeLogger branch(TreeLogger.Type type, String message, Throwable t) { |
| return logOrBranch(type, message, t, true); |
| } |
| |
| public void error(CSSParseException exception) throws CSSException { |
| // TODO Since this indicates a loss of data, should this be a fatal error? |
| log(TreeLogger.WARN, exception); |
| } |
| |
| public void fatalError(CSSParseException exception) throws CSSException { |
| log(TreeLogger.ERROR, exception); |
| } |
| |
| public void log(TreeLogger.Type type, String message) { |
| log(type, message, null); |
| } |
| |
| public void log(TreeLogger.Type type, String message, Throwable t) { |
| logOrBranch(type, message, t, false); |
| } |
| |
| public void warning(CSSParseException exception) throws CSSException { |
| log(TreeLogger.DEBUG, exception); |
| } |
| |
| private void log(TreeLogger.Type type, CSSParseException e) { |
| log(type, "Line " + e.getLineNumber() + " column " + e.getColumnNumber() |
| + ": " + e.getMessage()); |
| } |
| |
| private TreeLogger logOrBranch(TreeLogger.Type type, String message, |
| Throwable t, boolean branch) { |
| fatalErrorEncountered |= type == TreeLogger.ERROR; |
| if (parentLogger.isLoggable(type)) { |
| maybeBranch(); |
| if (branch) { |
| return logger.branch(type, message, t); |
| } else { |
| logger.log(type, message, t); |
| return null; |
| } |
| } else { |
| return TreeLogger.NULL; |
| } |
| } |
| |
| private void maybeBranch() { |
| if (logger == null) { |
| logger = parentLogger.branch(TreeLogger.INFO, |
| "The following problems were detected"); |
| } |
| } |
| } |
| |
| /** |
| * Maps the SAC model into our own CSS AST nodes. |
| */ |
| private static class GenerationHandler implements DocumentHandler { |
| /** |
| * The stylesheet that is being composed. |
| */ |
| private final CssStylesheet css = new CssStylesheet(); |
| |
| /** |
| * Accumulates CSS nodes as they are created. |
| */ |
| private final Stack<HasNodes> currentParent = new Stack<HasNodes>(); |
| |
| /** |
| * Accumulates CSS properties as they are seen. |
| */ |
| private HasProperties currentRule; |
| |
| /** |
| * Records references to {@code @def} rules. |
| */ |
| private final Map<String, CssDef> defs = new HashMap<String, CssDef>(); |
| |
| /** |
| * Used when parsing the contents of meta-styles. |
| */ |
| private final Errors errors; |
| |
| /** |
| * Used by {@link #startSelector(SelectorList)} to suppress the creation of |
| * new CssRules in favor of retaining {@link #currentRule}. |
| */ |
| private boolean nextSelectorCreatesRule = true; |
| |
| public GenerationHandler(Errors errors) { |
| this.errors = errors; |
| currentParent.push(css); |
| } |
| |
| public void comment(String text) throws CSSException { |
| // Ignore comments |
| // TODO Should comments be retained but not generally printed? |
| } |
| |
| public void endDocument(InputSource source) throws CSSException { |
| } |
| |
| public void endFontFace() throws CSSException { |
| } |
| |
| public void endMedia(SACMediaList media) throws CSSException { |
| currentParent.pop(); |
| } |
| |
| public void endPage(String name, String pseudoPage) throws CSSException { |
| } |
| |
| public void endSelector(SelectorList selectors) throws CSSException { |
| } |
| |
| /** |
| * Reflectively invoke a method named parseRule on this instance. |
| */ |
| public void ignorableAtRule(String atRule) throws CSSException { |
| int idx = atRule.indexOf(" "); |
| if (idx == -1) { |
| // Empty rule like @foo; |
| addNode(new CssUnknownAtRule(atRule)); |
| return; |
| } |
| String ruleName = atRule.substring(1, idx); |
| String methodName = "parse" + (Character.toUpperCase(ruleName.charAt(0))) |
| + StringCase.toLower(ruleName.substring(1)); |
| try { |
| Method parseMethod = getClass().getDeclaredMethod(methodName, |
| String.class); |
| parseMethod.invoke(this, atRule); |
| } catch (NoSuchMethodException e) { |
| // A rule like @-webkit-keyframe {...} that we can't process |
| addNode(new CssUnknownAtRule(atRule)); |
| } catch (IllegalAccessException e) { |
| errors.log(TreeLogger.ERROR, "Unable to invoke parse method ", e); |
| } catch (InvocationTargetException e) { |
| Throwable cause = e.getCause(); |
| |
| if (cause instanceof CSSException) { |
| // Unwind a CSSException normally |
| throw (CSSException) cause; |
| } else if (cause != null) { |
| // Otherwise, report the message nicely |
| TreeLogger details = errors.branch(TreeLogger.ERROR, |
| cause.getMessage()); |
| details.log(TreeLogger.DEBUG, "Full stack trace", cause); |
| } else { |
| TreeLogger details = errors.branch(TreeLogger.ERROR, |
| "Unknown failure parsing " + ruleName); |
| details.log(TreeLogger.DEBUG, "Full stack trace", e); |
| } |
| } |
| } |
| |
| public void importStyle(String uri, SACMediaList media, |
| String defaultNamespaceURI) throws CSSException { |
| } |
| |
| public void namespaceDeclaration(String prefix, String uri) |
| throws CSSException { |
| } |
| |
| public void property(String name, LexicalUnit value, boolean important) |
| throws CSSException { |
| List<Value> values = new ArrayList<Value>(); |
| if (value != null) { |
| extractValueOf(values, value); |
| } |
| currentRule.getProperties().add( |
| new CssProperty(escapeIdent(name), new ListValue(values), important)); |
| } |
| |
| public void startDocument(InputSource source) throws CSSException { |
| } |
| |
| public void startFontFace() throws CSSException { |
| CssFontFace rule = new CssFontFace(); |
| addNode(rule); |
| currentRule = rule; |
| } |
| |
| public void startMedia(SACMediaList media) throws CSSException { |
| CssMediaRule r = new CssMediaRule(); |
| for (int i = 0; i < media.getLength(); i++) { |
| r.getMedias().add(media.item(i)); |
| } |
| |
| pushParent(r); |
| } |
| |
| public void startPage(String name, String pseudoPage) throws CSSException { |
| CssPageRule r = new CssPageRule(); |
| // name appears to be unused in CSS2 |
| r.setPseudoPage(pseudoPage); |
| addNode(r); |
| currentRule = r; |
| } |
| |
| public void startSelector(SelectorList selectors) throws CSSException { |
| CssRule r; |
| |
| if (nextSelectorCreatesRule) { |
| r = new CssRule(); |
| addNode(r); |
| currentRule = r; |
| } else { |
| r = (CssRule) currentRule; |
| nextSelectorCreatesRule = true; |
| } |
| |
| for (int i = 0; i < selectors.getLength(); i++) { |
| r.getSelectors().add(new CssSelector(valueOf(selectors.item(i)))); |
| } |
| } |
| |
| void parseCharset(String atRule) { |
| // A charset at-rule is not relevant inside a style element. Ignore it |
| |
| errors.log(TreeLogger.WARN, |
| "Charset declaration detected. A charset at-rule is not relevant inside a style element"); |
| } |
| |
| void parseDef(String atRule) { |
| String value = atRule.substring(4, atRule.length()).trim(); |
| |
| InputSource s = new InputSource(); |
| s.setCharacterStream(new StringReader(value)); |
| Parser parser = new Parser(); |
| parser.setErrorHandler(errors); |
| |
| final List<Value> values = new ArrayList<Value>(); |
| parser.setDocumentHandler(new PropertyExtractor(values)); |
| |
| try { |
| String dummy = "* { prop : " + value + "}"; |
| parser.parseStyleSheet(new InputSource(new StringReader(dummy))); |
| } catch (IOException e) { |
| assert false : "Should never happen"; |
| } |
| |
| if (values.size() < 2) { |
| throw new CSSException(CSSException.SAC_SYNTAX_ERR, |
| "@def rules must specify an identifier and one or more values", |
| null); |
| } |
| |
| IdentValue defName = values.get(0).isIdentValue(); |
| |
| if (defName == null) { |
| throw new CSSException(CSSException.SAC_SYNTAX_ERR, |
| "First lexical unit must be an identifier", null); |
| } |
| |
| /* |
| * Replace any references to previously-seen @def constructs. We do |
| * expansion up-front to prevent the need for cycle-detection later. |
| */ |
| for (ListIterator<Value> it = values.listIterator(1); it.hasNext();) { |
| IdentValue maybeDefReference = it.next().isIdentValue(); |
| if (maybeDefReference != null) { |
| CssDef previousDef = defs.get(maybeDefReference.getIdent()); |
| if (previousDef != null) { |
| it.remove(); |
| for (Value previousValue : previousDef.getValues()) { |
| it.add(previousValue); |
| } |
| } |
| } |
| } |
| |
| CssDef def = new CssDef(defName.getIdent()); |
| def.getValues().addAll(values.subList(1, values.size())); |
| addNode(def); |
| |
| defs.put(defName.getIdent(), def); |
| } |
| |
| /** |
| * The elif nodes are processed as though they were {@code @if} nodes. The |
| * newly-generated CssIf node will be attached to the last CssIf in the |
| * if/else chain. |
| */ |
| void parseElif(String atRule) throws CSSException { |
| List<CssNode> nodes = currentParent.peek().getNodes(); |
| CssIf lastIf = findLastIfInChain(nodes); |
| |
| if (lastIf == null) { |
| throw new CSSException(CSSException.SAC_SYNTAX_ERR, |
| "@elif must immediately follow an @if or @elif", null); |
| } |
| |
| assert lastIf.getElseNodes().isEmpty(); |
| |
| // @elif -> lif (because parseIf strips the first three chars) |
| parseIf(atRule.substring(2)); |
| |
| // Fix up the structure by remove the newly-created node from the parent |
| // context and moving it to the end of the @if chain |
| lastIf.getElseNodes().add(nodes.remove(nodes.size() - 1)); |
| } |
| |
| /** |
| * The else nodes are processed as though they were written as {@code @elif |
| * true} rules. |
| */ |
| void parseElse(String atRule) throws CSSException { |
| // The last CssIf in the if/else chain |
| CssIf lastIf = findLastIfInChain(currentParent.peek().getNodes()); |
| |
| if (lastIf == null) { |
| throw new CSSException(CSSException.SAC_SYNTAX_ERR, |
| "@else must immediately follow an @if or @elif", null); |
| } |
| |
| // Create the CssIf to hold the @else rules |
| String fakeElif = "@elif (true) " + atRule.substring(atRule.indexOf("{")); |
| parseElif(fakeElif); |
| CssIf elseIf = findLastIfInChain(currentParent.peek().getNodes()); |
| |
| assert lastIf.getElseNodes().size() == 1 |
| && lastIf.getElseNodes().get(0) == elseIf; |
| assert elseIf.getElseNodes().isEmpty(); |
| |
| // Merge the rules into the last CssIf to break the chain and prevent |
| // @else followed by @else |
| lastIf.getElseNodes().clear(); |
| lastIf.getElseNodes().addAll(elseIf.getNodes()); |
| } |
| |
| void parseEval(String atRule) throws CSSException { |
| // @eval key com.google.Type.staticFunction |
| String[] parts = atRule.substring(0, atRule.length() - 1).split("\\s"); |
| |
| if (parts.length != 3) { |
| throw new CSSException(CSSException.SAC_SYNTAX_ERR, |
| "Incorrect number of parts for @eval", null); |
| } |
| |
| CssEval eval = new CssEval(parts[1], parts[2]); |
| addNode(eval); |
| } |
| |
| void parseExternal(String atRule) throws CSSException { |
| // @external .foo, bar; Drop the dots and commas |
| String[] parts = atRule.substring(10, atRule.length() - 1).replaceAll( |
| "(, *)|( +)", " ").replaceAll("\\.", "").split(" "); |
| |
| CssExternalSelectors externals = new CssExternalSelectors(); |
| Collections.addAll(externals.getClasses(), parts); |
| addNode(externals); |
| } |
| |
| void parseIf(String atRule) throws CSSException { |
| String predicate = atRule.substring(3, atRule.indexOf('{') - 1).trim(); |
| String blockContents = atRule.substring(atRule.indexOf('{') + 1, |
| atRule.length() - 1); |
| |
| CssIf cssIf = new CssIf(); |
| |
| if (predicate.startsWith("(") && predicate.endsWith(")")) { |
| cssIf.setExpression(predicate); |
| } else { |
| |
| String[] predicateParts = predicate.split("\\s"); |
| |
| switch (predicateParts.length) { |
| case 0: |
| throw new CSSException(CSSException.SAC_SYNTAX_ERR, |
| "Incorrect format for @if predicate", null); |
| case 1: |
| if (predicateParts[0].length() == 0) { |
| throw new CSSException(CSSException.SAC_SYNTAX_ERR, |
| "Incorrect format for @if predicate", null); |
| } |
| errors.log( |
| TreeLogger.WARN, |
| "Deprecated syntax for Java expression detected. Enclose the expression in parentheses"); |
| cssIf.setExpression(predicateParts[0]); |
| break; |
| default: |
| if (predicateParts[0].startsWith("!")) { |
| cssIf.setNegated(true); |
| cssIf.setProperty(predicateParts[0].substring(1)); |
| } else { |
| cssIf.setProperty(predicateParts[0]); |
| } |
| String[] values = new String[predicateParts.length - 1]; |
| System.arraycopy(predicateParts, 1, values, 0, values.length); |
| cssIf.setPropertyValues(values); |
| } |
| } |
| |
| parseInnerStylesheet("@if", cssIf, blockContents); |
| } |
| |
| void parseNoflip(String atRule) throws CSSException { |
| String blockContents = atRule.substring(atRule.indexOf('{') + 1, |
| atRule.length() - 1); |
| |
| parseInnerStylesheet("@noflip", new CssNoFlip(), blockContents); |
| } |
| |
| void parseSprite(String atRule) throws CSSException { |
| CssSprite sprite = new CssSprite(); |
| currentRule = sprite; |
| addNode(sprite); |
| |
| // Flag to tell startSelector() to use the CssSprite instead of creating |
| // its own CssRule. |
| nextSelectorCreatesRule = false; |
| |
| // parse the inner text |
| InputSource s = new InputSource(); |
| s.setCharacterStream(new StringReader(atRule.substring(7))); |
| Parser parser = new Parser(); |
| parser.setDocumentHandler(this); |
| parser.setErrorHandler(errors); |
| |
| try { |
| parser.parseRule(s); |
| } catch (IOException e) { |
| throw new CSSException(CSSException.SAC_SYNTAX_ERR, |
| "Unable to parse @sprite", e); |
| } |
| } |
| |
| void parseUrl(String atRule) throws CSSException { |
| // @url key dataResourceFunction |
| String[] parts = atRule.substring(0, atRule.length() - 1).split("\\s"); |
| |
| if (parts.length != 3) { |
| throw new CSSException(CSSException.SAC_SYNTAX_ERR, |
| "Incorrect number of parts for @url", null); |
| } |
| |
| CssUrl url = new CssUrl(parts[1], parts[2]); |
| addNode(url); |
| } |
| |
| /** |
| * Add a node to the current parent. |
| */ |
| private void addNode(CssNode node) { |
| currentParent.peek().getNodes().add(node); |
| } |
| |
| private <T extends CssNode & HasNodes> void parseInnerStylesheet( |
| String tagName, T parent, String blockContents) { |
| pushParent(parent); |
| |
| // parse the inner text |
| InputSource s = new InputSource(); |
| s.setCharacterStream(new StringReader(blockContents)); |
| Parser parser = new Parser(); |
| parser.setDocumentHandler(this); |
| parser.setErrorHandler(errors); |
| |
| try { |
| parser.parseStyleSheet(s); |
| } catch (IOException e) { |
| throw new CSSException(CSSException.SAC_SYNTAX_ERR, "Unable to parse " |
| + tagName, e); |
| } |
| |
| if (currentParent.pop() != parent) { |
| // This is a coding error |
| throw new RuntimeException("Incorrect element popped"); |
| } |
| } |
| |
| /** |
| * Adds a node to the current parent and then makes the node the current |
| * parent node. |
| */ |
| private <T extends CssNode & HasNodes> void pushParent(T newParent) { |
| addNode(newParent); |
| currentParent.push(newParent); |
| } |
| } |
| |
| /** |
| * Extracts all properties in a document into a List. |
| */ |
| private static class PropertyExtractor implements DocumentHandler { |
| private final List<Value> values; |
| |
| private PropertyExtractor(List<Value> values) { |
| this.values = values; |
| } |
| |
| public void comment(String text) throws CSSException { |
| } |
| |
| public void endDocument(InputSource source) throws CSSException { |
| } |
| |
| public void endFontFace() throws CSSException { |
| } |
| |
| public void endMedia(SACMediaList media) throws CSSException { |
| } |
| |
| public void endPage(String name, String pseudoPage) throws CSSException { |
| } |
| |
| public void endSelector(SelectorList selectors) throws CSSException { |
| } |
| |
| public void ignorableAtRule(String atRule) throws CSSException { |
| } |
| |
| public void importStyle(String uri, SACMediaList media, |
| String defaultNamespaceURI) throws CSSException { |
| } |
| |
| public void namespaceDeclaration(String prefix, String uri) |
| throws CSSException { |
| } |
| |
| public void property(String name, LexicalUnit value, boolean important) |
| throws CSSException { |
| extractValueOf(values, value); |
| } |
| |
| public void startDocument(InputSource source) throws CSSException { |
| } |
| |
| public void startFontFace() throws CSSException { |
| } |
| |
| public void startMedia(SACMediaList media) throws CSSException { |
| } |
| |
| public void startPage(String name, String pseudoPage) throws CSSException { |
| } |
| |
| public void startSelector(SelectorList selectors) throws CSSException { |
| } |
| } |
| |
| /** |
| * Associates a template CssStylesheet with a timestamp. |
| */ |
| private static class CachedStylesheet { |
| private final CssStylesheet sheet; |
| private final long timestamp; |
| |
| public CachedStylesheet(CssStylesheet sheet, long timestamp) { |
| this.sheet = sheet; |
| this.timestamp = timestamp; |
| } |
| |
| public CssStylesheet getCopyOfStylesheet() { |
| return new CssStylesheet(sheet); |
| } |
| |
| public long getTimestamp() { |
| return timestamp; |
| } |
| } |
| |
| private static final String LITERAL_FUNCTION_NAME = "literal"; |
| /** |
| * We cache the stylesheets to prevent repeated parsing of the same source |
| * material. This is a common case if the user is using UiBinder's implicit |
| * stylesheets. It is necessary to use the list of URLs passed to exec because |
| * of the eager variable expansion performed by |
| * {@link GenerationHandler#parseDef(String)}. |
| */ |
| private static final Map<List<URL>, SoftReference<CachedStylesheet>> SHEETS = Collections.synchronizedMap(new HashMap<List<URL>, SoftReference<CachedStylesheet>>()); |
| private static final String VALUE_FUNCTION_NAME = "value"; |
| |
| /** |
| * Create a CssStylesheet from the contents of one or more URLs. If multiple |
| * URLs are provided, the generated stylesheet will be created as though the |
| * contents of the URLs had been concatenated. |
| */ |
| public static CssStylesheet exec(TreeLogger logger, URL... stylesheets) |
| throws UnableToCompleteException { |
| |
| long mtime = ResourceGeneratorUtil.getLastModified(stylesheets, logger); |
| |
| List<URL> sheets = Arrays.asList(stylesheets); |
| SoftReference<CachedStylesheet> ref = SHEETS.get(sheets); |
| CachedStylesheet toReturn = ref == null ? null : ref.get(); |
| if (toReturn != null) { |
| if (mtime != 0 && mtime <= toReturn.getTimestamp()) { |
| logger.log(TreeLogger.DEBUG, "Using cached result"); |
| return toReturn.getCopyOfStylesheet(); |
| } else { |
| logger.log(TreeLogger.DEBUG, "Invalidating cached stylesheet"); |
| } |
| } |
| |
| Parser p = new Parser(); |
| Errors errors = new Errors(logger); |
| GenerationHandler g = new GenerationHandler(errors); |
| p.setDocumentHandler(g); |
| p.setErrorHandler(errors); |
| |
| for (URL stylesheet : sheets) { |
| TreeLogger branchLogger = logger.branch(TreeLogger.DEBUG, |
| "Parsing CSS stylesheet " + stylesheet.toExternalForm()); |
| try { |
| p.parseStyleSheet(stylesheet.toURI().toString()); |
| continue; |
| } catch (CSSException e) { |
| branchLogger.log(TreeLogger.ERROR, "Unable to parse CSS", e); |
| } catch (IOException e) { |
| branchLogger.log(TreeLogger.ERROR, "Unable to parse CSS", e); |
| } catch (URISyntaxException e) { |
| branchLogger.log(TreeLogger.ERROR, "Unable to parse CSS", e); |
| } |
| throw new UnableToCompleteException(); |
| } |
| |
| if (errors.fatalErrorEncountered) { |
| // Logging will have been performed by the Errors instance, just exit |
| throw new UnableToCompleteException(); |
| } |
| |
| toReturn = new CachedStylesheet(g.css, mtime); |
| SHEETS.put(new ArrayList<URL>(sheets), new SoftReference<CachedStylesheet>( |
| toReturn)); |
| return toReturn.getCopyOfStylesheet(); |
| } |
| |
| /** |
| * Expresses an rgb function as a hex expression. |
| * |
| * @param colors a sequence of LexicalUnits, assumed to be |
| * <code>(VAL COMMA VAL COMMA VAL)</code> where VAL can be an INT or |
| * a PERCENT (which is then converted to INT) |
| * @return the minimal hex expression for the RGB color values |
| */ |
| private static Value colorValue(LexicalUnit colors) { |
| LexicalUnit red = colors; |
| int r = getRgbComponentValue(red); |
| LexicalUnit green = red.getNextLexicalUnit().getNextLexicalUnit(); |
| int g = getRgbComponentValue(green); |
| LexicalUnit blue = green.getNextLexicalUnit().getNextLexicalUnit(); |
| int b = getRgbComponentValue(blue); |
| |
| String sr = Integer.toHexString(r); |
| if (sr.length() == 1) { |
| sr = "0" + sr; |
| } |
| |
| String sg = Integer.toHexString(g); |
| if (sg.length() == 1) { |
| sg = "0" + sg; |
| } |
| |
| String sb = Integer.toHexString(b); |
| if (sb.length() == 1) { |
| sb = "0" + sb; |
| } |
| |
| // #AABBCC --> #ABC |
| if (sr.charAt(0) == sr.charAt(1) && sg.charAt(0) == sg.charAt(1) |
| && sb.charAt(0) == sb.charAt(1)) { |
| sr = sr.substring(1); |
| sg = sg.substring(1); |
| sb = sb.substring(1); |
| } |
| |
| return new IdentValue("#" + sr + sg + sb); |
| } |
| |
| private static String escapeIdent(String selector) { |
| assert selector.length() > 0; |
| |
| StringBuilder toReturn = new StringBuilder(); |
| |
| if (selector.charAt(0) == '-') { |
| // Allow leading hyphen |
| selector = selector.substring(1); |
| toReturn.append('-'); |
| } |
| |
| if (!isIdentStart(selector.charAt(0))) { |
| toReturn.append('\\'); |
| } |
| toReturn.append(selector.charAt(0)); |
| |
| if (selector.length() > 1) { |
| for (char c : selector.substring(1).toCharArray()) { |
| if (!isIdentPart(c)) { |
| toReturn.append('\\'); |
| } |
| toReturn.append(c); |
| } |
| } |
| return toReturn.toString(); |
| } |
| |
| /** |
| * Convert a LexicalUnit list into a List of Values. |
| */ |
| private static void extractValueOf(List<Value> accumulator, LexicalUnit value) { |
| do { |
| accumulator.add(valueOf(value)); |
| value = value.getNextLexicalUnit(); |
| } while (value != null); |
| } |
| |
| /** |
| * The elif and else constructs are modeled as nested if statements in the |
| * CssIf's elseNodes field. This method will search a list of CssNodes and |
| * remove the last chained CssIf from the last element in the list of nodes. |
| */ |
| private static CssIf findLastIfInChain(List<CssNode> nodes) { |
| if (nodes.isEmpty()) { |
| return null; |
| } |
| |
| CssNode lastNode = nodes.get(nodes.size() - 1); |
| if (lastNode instanceof CssIf) { |
| CssIf asIf = (CssIf) lastNode; |
| if (asIf.getElseNodes().isEmpty()) { |
| return asIf; |
| } else { |
| return findLastIfInChain(asIf.getElseNodes()); |
| } |
| } |
| return null; |
| } |
| |
| /** |
| * Return an integer value from 0-255 for a component of an RGB color. |
| * |
| * @param color typed value from the CSS parser, which may be an INTEGER or a |
| * PERCENTAGE |
| * @return integer value from 0-255 |
| * @throws IllegalArgumentException if the color is not an INTEGER or |
| * PERCENTAGE value |
| */ |
| private static int getRgbComponentValue(LexicalUnit color) { |
| switch (color.getLexicalUnitType()) { |
| case LexicalUnit.SAC_INTEGER: |
| return Math.min(color.getIntegerValue(), 255); |
| case LexicalUnit.SAC_PERCENTAGE: |
| return (int) Math.min(color.getFloatValue() * 255, 255); |
| default: |
| throw new CSSException(CSSException.SAC_SYNTAX_ERR, |
| "RGB component value must be integer or percentage, was " + color, |
| null); |
| } |
| } |
| |
| private static boolean isIdentPart(char c) { |
| return Character.isLetterOrDigit(c) || (c == '\\') || (c == '-') |
| || (c == '_'); |
| } |
| |
| private static boolean isIdentStart(char c) { |
| return Character.isLetter(c) || (c == '\\') || (c == '_'); |
| } |
| |
| /** |
| * Utility method to concatenate strings. |
| */ |
| private static String join(Iterable<Value> elements, String separator) { |
| StringBuilder b = new StringBuilder(); |
| for (Iterator<Value> i = elements.iterator(); i.hasNext();) { |
| b.append(i.next().toCss()); |
| if (i.hasNext()) { |
| b.append(separator); |
| } |
| } |
| return b.toString(); |
| } |
| |
| private static String maybeUnquote(String s) { |
| if (s.startsWith("\"") && s.endsWith("\"")) { |
| return s.substring(1, s.length() - 1); |
| } |
| return s; |
| } |
| |
| /** |
| * Used when evaluating literal() rules. |
| */ |
| private static String unescapeLiteral(String s) { |
| s = s.replaceAll(Pattern.quote("\\\""), "\""); |
| s = s.replaceAll(Pattern.quote("\\\\"), Matcher.quoteReplacement("\\")); |
| return s; |
| } |
| |
| private static String valueOf(Condition condition) { |
| if (condition instanceof AttributeCondition) { |
| AttributeCondition c = (AttributeCondition) condition; |
| switch (c.getConditionType()) { |
| case Condition.SAC_ATTRIBUTE_CONDITION: |
| return "[" + c.getLocalName() |
| + (c.getValue() != null ? "=\"" + c.getValue() + '"' : "") + "]"; |
| case Condition.SAC_ONE_OF_ATTRIBUTE_CONDITION: |
| return "[" + c.getLocalName() + "~=\"" + c.getValue() + "\"]"; |
| case Condition.SAC_BEGIN_HYPHEN_ATTRIBUTE_CONDITION: |
| return "[" + c.getLocalName() + "|=\"" + c.getValue() + "\"]"; |
| case Condition.SAC_ID_CONDITION: |
| return "#" + c.getValue(); |
| case Condition.SAC_CLASS_CONDITION: |
| return "." + c.getValue(); |
| case Condition.SAC_PSEUDO_CLASS_CONDITION: |
| return ":" + c.getValue(); |
| } |
| |
| } else if (condition instanceof CombinatorCondition) { |
| CombinatorCondition c = (CombinatorCondition) condition; |
| switch (condition.getConditionType()) { |
| case Condition.SAC_AND_CONDITION: |
| return valueOf(c.getFirstCondition()) |
| + valueOf(c.getSecondCondition()); |
| case Condition.SAC_OR_CONDITION: |
| // Unimplemented in CSS2? |
| } |
| |
| } else if (condition instanceof ContentCondition) { |
| // Unimplemented in CSS2? |
| |
| } else if (condition instanceof LangCondition) { |
| LangCondition c = (LangCondition) condition; |
| return ":lang(" + c.getLang() + ")"; |
| |
| } else if (condition instanceof NegativeCondition) { |
| // Unimplemented in CSS2? |
| } else if (condition instanceof PositionalCondition) { |
| // Unimplemented in CSS2? |
| } |
| |
| throw new RuntimeException("Unhandled condition of type " |
| + condition.getConditionType() + " " + condition.getClass().getName()); |
| } |
| |
| private static Value valueOf(LexicalUnit value) { |
| switch (value.getLexicalUnitType()) { |
| case LexicalUnit.SAC_ATTR: |
| return new IdentValue("attr(" + value.getStringValue() + ")"); |
| case LexicalUnit.SAC_IDENT: |
| return new IdentValue(escapeIdent(value.getStringValue())); |
| case LexicalUnit.SAC_STRING_VALUE: |
| return new StringValue(value.getStringValue()); |
| case LexicalUnit.SAC_RGBCOLOR: |
| // flute models the commas as operators so no separator needed |
| return colorValue(value.getParameters()); |
| case LexicalUnit.SAC_INTEGER: |
| return new NumberValue(value.getIntegerValue()); |
| case LexicalUnit.SAC_REAL: |
| return new NumberValue(value.getFloatValue()); |
| case LexicalUnit.SAC_CENTIMETER: |
| case LexicalUnit.SAC_DEGREE: |
| case LexicalUnit.SAC_DIMENSION: |
| case LexicalUnit.SAC_EM: |
| case LexicalUnit.SAC_EX: |
| case LexicalUnit.SAC_GRADIAN: |
| case LexicalUnit.SAC_HERTZ: |
| case LexicalUnit.SAC_KILOHERTZ: |
| case LexicalUnit.SAC_MILLIMETER: |
| case LexicalUnit.SAC_MILLISECOND: |
| case LexicalUnit.SAC_PERCENTAGE: |
| case LexicalUnit.SAC_PICA: |
| case LexicalUnit.SAC_PIXEL: |
| case LexicalUnit.SAC_POINT: |
| case LexicalUnit.SAC_RADIAN: |
| case LexicalUnit.SAC_SECOND: |
| return new NumberValue(value.getFloatValue(), |
| value.getDimensionUnitText()); |
| case LexicalUnit.SAC_URI: |
| return new IdentValue("url(" + value.getStringValue() + ")"); |
| case LexicalUnit.SAC_OPERATOR_COMMA: |
| return new TokenValue(","); |
| case LexicalUnit.SAC_COUNTER_FUNCTION: |
| case LexicalUnit.SAC_COUNTERS_FUNCTION: |
| case LexicalUnit.SAC_FUNCTION: { |
| if (value.getFunctionName().equals(VALUE_FUNCTION_NAME)) { |
| // This is a call to value() |
| List<Value> params = new ArrayList<Value>(); |
| extractValueOf(params, value.getParameters()); |
| |
| if (params.size() != 1 && params.size() != 3) { |
| throw new CSSException(CSSException.SAC_SYNTAX_ERR, |
| "Incorrect number of parameters to " + VALUE_FUNCTION_NAME, |
| null); |
| } |
| |
| Value dotPathValue = params.get(0); |
| String dotPath = maybeUnquote(((StringValue) dotPathValue).getValue()); |
| String suffix = params.size() == 3 |
| ? maybeUnquote(((StringValue) params.get(2)).getValue()) : ""; |
| |
| return new DotPathValue(dotPath, suffix); |
| } else if (value.getFunctionName().equals(LITERAL_FUNCTION_NAME)) { |
| // This is a call to value() |
| List<Value> params = new ArrayList<Value>(); |
| extractValueOf(params, value.getParameters()); |
| |
| if (params.size() != 1) { |
| throw new CSSException(CSSException.SAC_SYNTAX_ERR, |
| "Incorrect number of parameters to " + LITERAL_FUNCTION_NAME, |
| null); |
| } |
| |
| Value expression = params.get(0); |
| if (!(expression instanceof StringValue)) { |
| throw new CSSException(CSSException.SAC_SYNTAX_ERR, |
| "The single argument to " + LITERAL_FUNCTION_NAME |
| + " must be a string value", null); |
| } |
| |
| String s = maybeUnquote(((StringValue) expression).getValue()); |
| s = unescapeLiteral(s); |
| |
| return new IdentValue(s); |
| |
| } else { |
| List<Value> parameters = new ArrayList<Value>(); |
| extractValueOf(parameters, value.getParameters()); |
| return new FunctionValue(value.getFunctionName(), |
| new ListValue(parameters)); |
| } |
| } |
| case LexicalUnit.SAC_INHERIT: |
| return new IdentValue("inherit"); |
| case LexicalUnit.SAC_OPERATOR_EXP: |
| return new TokenValue("^"); |
| case LexicalUnit.SAC_OPERATOR_GE: |
| return new TokenValue(">="); |
| case LexicalUnit.SAC_OPERATOR_GT: |
| return new TokenValue(">"); |
| case LexicalUnit.SAC_OPERATOR_LE: |
| return new TokenValue("<="); |
| case LexicalUnit.SAC_OPERATOR_LT: |
| return new TokenValue("<"); |
| case LexicalUnit.SAC_OPERATOR_MINUS: |
| return new TokenValue("-"); |
| case LexicalUnit.SAC_OPERATOR_MOD: |
| return new TokenValue("%"); |
| case LexicalUnit.SAC_OPERATOR_MULTIPLY: |
| return new TokenValue("*"); |
| case LexicalUnit.SAC_OPERATOR_PLUS: |
| return new TokenValue("+"); |
| case LexicalUnit.SAC_OPERATOR_SLASH: |
| return new TokenValue("/"); |
| case LexicalUnit.SAC_OPERATOR_TILDE: |
| return new IdentValue("~"); |
| case LexicalUnit.SAC_RECT_FUNCTION: { |
| // Just return this as a String |
| List<Value> parameters = new ArrayList<Value>(); |
| extractValueOf(parameters, value.getParameters()); |
| return new IdentValue("rect(" + join(parameters, "") + ")"); |
| } |
| case LexicalUnit.SAC_SUB_EXPRESSION: |
| // Should have been taken care of by our own traversal |
| case LexicalUnit.SAC_UNICODERANGE: |
| // Cannot be expressed in CSS2 |
| } |
| throw new RuntimeException("Unhandled LexicalUnit type " |
| + value.getLexicalUnitType()); |
| } |
| |
| private static String valueOf(Selector selector) { |
| if (selector instanceof CharacterDataSelector) { |
| // Unimplemented in CSS2? |
| |
| } else if (selector instanceof ConditionalSelector) { |
| ConditionalSelector s = (ConditionalSelector) selector; |
| String simpleSelector = valueOf(s.getSimpleSelector()); |
| |
| if ("*".equals(simpleSelector)) { |
| // Don't need the extra * for compound selectors |
| return valueOf(s.getCondition()); |
| } else { |
| return simpleSelector + valueOf(s.getCondition()); |
| } |
| |
| } else if (selector instanceof DescendantSelector) { |
| DescendantSelector s = (DescendantSelector) selector; |
| switch (s.getSelectorType()) { |
| case Selector.SAC_CHILD_SELECTOR: |
| if (s.getSimpleSelector().getSelectorType() == Selector.SAC_PSEUDO_ELEMENT_SELECTOR) { |
| return valueOf(s.getAncestorSelector()) + ":" |
| + valueOf(s.getSimpleSelector()); |
| } else { |
| return valueOf(s.getAncestorSelector()) + ">" |
| + valueOf(s.getSimpleSelector()); |
| } |
| case Selector.SAC_DESCENDANT_SELECTOR: |
| return valueOf(s.getAncestorSelector()) + " " |
| + valueOf(s.getSimpleSelector()); |
| } |
| |
| } else if (selector instanceof ElementSelector) { |
| ElementSelector s = (ElementSelector) selector; |
| if (s.getLocalName() == null) { |
| return "*"; |
| } else { |
| return escapeIdent(s.getLocalName()); |
| } |
| |
| } else if (selector instanceof NegativeSelector) { |
| // Unimplemented in CSS2? |
| |
| } else if (selector instanceof ProcessingInstructionSelector) { |
| // Unimplemented in CSS2? |
| |
| } else if (selector instanceof SiblingSelector) { |
| SiblingSelector s = (SiblingSelector) selector; |
| return valueOf(s.getSelector()) + "+" + valueOf(s.getSiblingSelector()); |
| } |
| |
| throw new RuntimeException("Unhandled selector of type " |
| + selector.getClass().getName()); |
| } |
| |
| /** |
| * Utility class. |
| */ |
| private GenerateCssAst() { |
| } |
| } |
