Java tutorial
/* * Copyright (C) 2013 The Android Open Source Project * * 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.jetbrains.android.inspections.lint; import com.google.common.base.Stopwatch; import com.intellij.openapi.util.TextRange; import com.intellij.openapi.vfs.VirtualFile; import com.intellij.psi.PsiElement; import com.intellij.psi.xml.*; import com.intellij.util.containers.HashMap; import org.jetbrains.annotations.NotNull; import org.jetbrains.annotations.Nullable; import org.w3c.dom.*; import java.util.ArrayList; import java.util.List; import java.util.Map; /** * Converter which takes a PSI hierarchy for an XML file or document, and * creates a corresponding W3C DOM tree. It attempts to delegate as much * as possible to the original PSI tree. Note also that the {@link #getTextRange(Node)}} * method allows us to look up source offsets for the DOM nodes (which plain XML * DOM parsers do not). * <p> * NOTE: The tree may not be semantically equivalent to the XML PSI structure; this * converter only attempts to make the DOM correct as far as Lint cares (meaning that it * only worries about the details Lint cares about; currently this means it only wraps elements, * text and comment nodes.) */ class DomPsiConverter { /** Whether to time initialization of each PSI and print some logging data */ private static final boolean BENCHMARK = false; private DomPsiConverter() { } /** * Convert the given {@link XmlFile} to a DOM tree * * @param xmlFile the file to be converted * @return a corresponding W3C DOM tree */ @Nullable public static Document convert(@NotNull XmlFile xmlFile) { try { XmlDocument xmlDocument = xmlFile.getDocument(); if (xmlDocument == null) { return null; } @SuppressWarnings("UnusedAssignment") Stopwatch timer; if (BENCHMARK) { timer = new Stopwatch(); timer.start(); } Document document = convert(xmlDocument); if (BENCHMARK) { timer.stop(); //noinspection UseOfSystemOutOrSystemErr System.out.println("Creating PSI for " + xmlFile.getName() + " took " + timer.elapsedMillis() + "ms (" + timer.toString() + ")"); } return document; } catch (Exception e) { String path = xmlFile.getName(); VirtualFile virtualFile = xmlFile.getVirtualFile(); if (virtualFile != null) { path = virtualFile.getPath(); } throw new RuntimeException("Could not convert file " + path, e); } } /** * Convert the given {@link XmlDocument} to a DOM tree * * @param document the document to be converted * @return a corresponding W3C DOM tree */ @Nullable private static Document convert(@NotNull XmlDocument document) { return new DomDocument(document); } /** Gets the {@link TextRange} for a {@link Node} created with this converter */ @NotNull public static TextRange getTextRange(@NotNull Node node) { assert node instanceof DomNode; DomNode domNode = (DomNode) node; XmlElement element = domNode.myElement; TextRange textRange = element.getTextRange(); // For elements, don't highlight the entire element range; instead, just // highlight the element name if (node.getNodeType() == Node.ELEMENT_NODE) { String tag = node.getNodeName(); int index = element.getText().indexOf(tag); if (index != -1) { int start = textRange.getStartOffset() + index; return new TextRange(start, start + tag.length()); } } return textRange; } private static final NodeList EMPTY = new NodeList() { @NotNull @Override public Node item(int i) { throw new IllegalArgumentException(); } @Override public int getLength() { return 0; } }; @Nullable private static final NamedNodeMap EMPTY_ATTRIBUTES = new NamedNodeMap() { @Override public int getLength() { return 0; } @Nullable @Override public Node getNamedItem(String s) { return null; } @Nullable @Override public Node getNamedItemNS(String s, String s2) throws DOMException { return null; } @NotNull @Override public Node setNamedItem(Node node) throws DOMException { throw new UnsupportedOperationException(); // Not supported } @NotNull @Override public Node removeNamedItem(String s) throws DOMException { throw new UnsupportedOperationException(); // Not supported } @NotNull @Override public Node item(int i) { throw new UnsupportedOperationException(); // Not supported } @Nullable @Override public Node setNamedItemNS(Node node) throws DOMException { return null; } @NotNull @Override public Node removeNamedItemNS(String s, String s2) throws DOMException { throw new UnsupportedOperationException(); // Not supported } }; private static class DomNodeList implements NodeList { protected final List<DomNode> myChildren = new ArrayList<DomNode>(); @NotNull @Override public Node item(int i) { return myChildren.get(i); } @Override public int getLength() { return myChildren.size(); } void add(@NotNull DomNode node) { int size = myChildren.size(); if (size > 0) { DomNode last = myChildren.get(size - 1); node.myPrevious = last; last.myNext = node; } myChildren.add(node); } } private static class DomNamedNodeMap implements NamedNodeMap { @NotNull protected final Map<String, DomNode> myMap; @NotNull protected final Map<String, Map<String, DomNode>> myNsMap; @NotNull protected final List<DomNode> mItems; private DomNamedNodeMap(@NotNull DomElement element, @NotNull XmlAttribute[] attributes) { int count = attributes.length; int namespaceCount = 0; for (XmlAttribute attribute : attributes) { if (!attribute.getNamespace().isEmpty()) { namespaceCount++; } } myMap = new HashMap<String, DomNode>(count - namespaceCount); myNsMap = new HashMap<String, Map<String, DomNode>>(namespaceCount); mItems = new ArrayList<DomNode>(count); assert element.myOwner != null; // True for elements, not true for non-Element nodes for (XmlAttribute attribute : attributes) { DomAttr attr = new DomAttr(element.myOwner, element, attribute); mItems.add(attr); String namespace = attribute.getNamespace(); if (!namespace.isEmpty()) { Map<String, DomNode> map = myNsMap.get(namespace); if (map == null) { map = new HashMap<String, DomNode>(); myNsMap.put(namespace, map); } map.put(attribute.getLocalName(), attr); } else { myMap.put(attribute.getName(), attr); } } } @Override public Node item(int i) { return mItems.get(i); } @Override public int getLength() { return mItems.size(); } @Override public Node getNamedItem(@NotNull String s) { return myMap.get(s); } @Nullable @Override public Node getNamedItemNS(@NotNull String namespace, @NotNull String name) throws DOMException { Map<String, DomNode> map = myNsMap.get(namespace); if (map != null) { return map.get(name); } return null; } @NotNull @Override public Node setNamedItem(Node node) throws DOMException { throw new UnsupportedOperationException(); // Read-only bridge } @NotNull @Override public Node removeNamedItem(String s) throws DOMException { throw new UnsupportedOperationException(); // Read-only bridge } @NotNull @Override public Node setNamedItemNS(Node node) throws DOMException { throw new UnsupportedOperationException(); // Read-only bridge } @NotNull @Override public Node removeNamedItemNS(String s, String s2) throws DOMException { throw new UnsupportedOperationException(); // Read-only bridge } } @SuppressWarnings({ "UnusedParameters", "UnusedDeclaration" }) // Specifies methods shared by children private static abstract class DomNode implements Node { @Nullable protected final Document myOwner; @Nullable protected final DomNode myParent; @NotNull protected final XmlElement myElement; @Nullable protected NodeList myChildren; @Nullable protected DomNode myNext; @Nullable protected DomNode myPrevious; protected DomNode(@Nullable Document owner, @Nullable DomNode parent, @NotNull XmlElement element) { myOwner = owner; myParent = parent; myElement = element; } @Nullable @Override public Node getParentNode() { return myParent; } @NotNull @Override public NodeList getChildNodes() { if (myChildren == null) { PsiElement[] children = myElement.getChildren(); if (children.length > 0) { DomNodeList list = new DomNodeList(); myChildren = list; // True except for in DomDocument, which has custom getChildNodes assert myOwner != null; for (PsiElement child : children) { if (child instanceof XmlTag) { list.add(new DomElement(myOwner, this, (XmlTag) child)); } else if (child instanceof XmlText) { list.add(new DomText(myOwner, this, (XmlText) child)); } else if (child instanceof XmlComment) { list.add(new DomComment(myOwner, this, (XmlComment) child)); } else { // Skipping other types for now; lint doesn't care about them. // TODO: Consider whether we need CDATA. } } } else { myChildren = EMPTY; } } return myChildren; } @Nullable @Override public Node getFirstChild() { NodeList childNodes = getChildNodes(); if (childNodes.getLength() > 0) { return childNodes.item(0); } return null; } @Nullable @Override public Node getLastChild() { NodeList childNodes = getChildNodes(); if (childNodes.getLength() > 0) { return childNodes.item(0); } return null; } @Nullable @Override public Node getPreviousSibling() { return myPrevious; } @Nullable @Override public Node getNextSibling() { return myNext; } @Nullable @Override public NamedNodeMap getAttributes() { throw new UnsupportedOperationException(); // Only supported on elements } @Nullable @Override public Document getOwnerDocument() { return myOwner; } @Override public void setNodeValue(String s) throws DOMException { throw new UnsupportedOperationException(); // Read-only bridge } @NotNull @Override public Node insertBefore(Node node, Node node2) throws DOMException { throw new UnsupportedOperationException(); // Read-only bridge } @NotNull @Override public Node replaceChild(Node node, Node node2) throws DOMException { throw new UnsupportedOperationException(); // Read-only bridge } @NotNull @Override public Node removeChild(Node node) throws DOMException { throw new UnsupportedOperationException(); // Read-only bridge } @NotNull @Override public Node appendChild(Node node) throws DOMException { throw new UnsupportedOperationException(); // Read-only bridge } @Override public boolean hasChildNodes() { return getChildNodes().getLength() > 0; } @NotNull @Override public Node cloneNode(boolean b) { throw new UnsupportedOperationException(); // Read-only bridge } @Override public void normalize() { } @Override public boolean isSupported(String s, String s2) { return false; } @NotNull @Override public String getNamespaceURI() { throw new UnsupportedOperationException(); // Only supported on elements in lint } @NotNull @Override public String getPrefix() { throw new UnsupportedOperationException(); // Only supported on elements in lint } @Override public void setPrefix(String s) throws DOMException { throw new UnsupportedOperationException(); // Read-only bridge } @Nullable @Override public String getLocalName() { return null; } @Override public boolean hasAttributes() { return false; } @Nullable @Override public String getBaseURI() { return null; } @Override public short compareDocumentPosition(Node node) throws DOMException { throw new UnsupportedOperationException(); // Not supported } @Override public String getTextContent() throws DOMException { return myElement.getText(); } @Override public void setTextContent(String s) throws DOMException { throw new UnsupportedOperationException(); // Read-only bridge } @Override public boolean isSameNode(Node node) { throw new UnsupportedOperationException(); // Not supported } @NotNull @Override public String lookupPrefix(String s) { throw new UnsupportedOperationException(); // Not supported } @Override public boolean isDefaultNamespace(String s) { throw new UnsupportedOperationException(); // Not supported } @NotNull @Override public String lookupNamespaceURI(String s) { throw new UnsupportedOperationException(); // Not supported } @Override public boolean isEqualNode(Node node) { throw new UnsupportedOperationException(); // Not supported } @NotNull @Override public Object getFeature(String s, String s2) { throw new UnsupportedOperationException(); // Not supported } @NotNull @Override public Object setUserData(String s, Object o, UserDataHandler userDataHandler) { throw new UnsupportedOperationException(); // Read-only bridge } @NotNull @Override public Object getUserData(String s) { throw new UnsupportedOperationException(); // Not supported } // From CharacterData @NotNull public String getData() throws DOMException { throw new UnsupportedOperationException(); // Read-only bridge } public void setData(String s) throws DOMException { throw new UnsupportedOperationException(); // Read-only bridge } public int getLength() { throw new UnsupportedOperationException(); // Read-only bridge } @NotNull public String substringData(int i, int i2) throws DOMException { throw new UnsupportedOperationException(); // Read-only bridge } public void appendData(String s) throws DOMException { throw new UnsupportedOperationException(); // Read-only bridge } public void insertData(int i, String s) throws DOMException { throw new UnsupportedOperationException(); // Read-only bridge } public void deleteData(int i, int i2) throws DOMException { throw new UnsupportedOperationException(); // Read-only bridge } public void replaceData(int i, int i2, String s) throws DOMException { throw new UnsupportedOperationException(); // Read-only bridge } } private static class DomDocument extends DomNode implements Document { @NotNull private final XmlDocument myPsiDocument; @Nullable private DomElement myRoot; private DomDocument(@NotNull XmlDocument document) { super(null, null, document); myPsiDocument = document; } // From org.w3c.dom.Node: @Nullable @Override public String getNodeName() { return null; } @Nullable @Override public String getNodeValue() throws DOMException { return null; } @Override public short getNodeType() { return Node.DOCUMENT_NODE; } @NotNull @Override public NodeList getChildNodes() { if (myChildren == null) { DomNodeList list = new DomNodeList(); myChildren = list; DomNode documentElement = (DomNode) getDocumentElement(); if (documentElement != null) { list.add(documentElement); } } return myChildren; } // From org.w3c.dom.Document: @NotNull @Override public DocumentType getDoctype() { throw new UnsupportedOperationException(); // Not supported } @NotNull @Override public DOMImplementation getImplementation() { throw new UnsupportedOperationException(); // Not supported } @Nullable @Override public Element getDocumentElement() { if (myRoot == null) { XmlTag rootTag = myPsiDocument.getRootTag(); if (rootTag == null) { return null; } myRoot = new DomElement(this, this, rootTag); } return myRoot; } @NotNull @Override public NodeList getElementsByTagName(String s) { Element root = getDocumentElement(); if (root != null) { return root.getElementsByTagName(s); } return EMPTY; } @NotNull @Override public NodeList getElementsByTagNameNS(String s, String s2) { throw new UnsupportedOperationException(); // Not supported } @NotNull @Override public Element createElement(String s) throws DOMException { throw new UnsupportedOperationException(); // Read-only bridge } @NotNull @Override public DocumentFragment createDocumentFragment() { throw new UnsupportedOperationException(); // Read-only bridge } @NotNull @Override public Text createTextNode(String s) { throw new UnsupportedOperationException(); // Read-only bridge } @NotNull @Override public Comment createComment(String s) { throw new UnsupportedOperationException(); // Read-only bridge } @NotNull @Override public CDATASection createCDATASection(String s) throws DOMException { throw new UnsupportedOperationException(); // Read-only bridge } @NotNull @Override public ProcessingInstruction createProcessingInstruction(String s, String s2) throws DOMException { throw new UnsupportedOperationException(); // Read-only bridge } @NotNull @Override public Attr createAttribute(String s) throws DOMException { throw new UnsupportedOperationException(); // Read-only bridge } @NotNull @Override public EntityReference createEntityReference(String s) throws DOMException { throw new UnsupportedOperationException(); // Read-only bridge } @NotNull @Override public Node importNode(Node node, boolean b) throws DOMException { throw new UnsupportedOperationException(); // Read-only bridge } @NotNull @Override public Element createElementNS(String s, String s2) throws DOMException { throw new UnsupportedOperationException(); // Read-only bridge } @NotNull @Override public Attr createAttributeNS(String s, String s2) throws DOMException { throw new UnsupportedOperationException(); // Read-only bridge } @NotNull @Override public Element getElementById(String s) { throw new UnsupportedOperationException(); // Not supported } @NotNull @Override public String getInputEncoding() { throw new UnsupportedOperationException(); // Not supported } @NotNull @Override public String getXmlEncoding() { throw new UnsupportedOperationException(); // Not supported } @Override public boolean getXmlStandalone() { throw new UnsupportedOperationException(); // Not supported } @Override public void setXmlStandalone(boolean b) throws DOMException { throw new UnsupportedOperationException(); // Read-only bridge } @NotNull @Override public String getXmlVersion() { throw new UnsupportedOperationException(); // Not supported } @Override public void setXmlVersion(String s) throws DOMException { throw new UnsupportedOperationException(); // Read-only bridge } @Override public boolean getStrictErrorChecking() { throw new UnsupportedOperationException(); // Not supported } @Override public void setStrictErrorChecking(boolean b) { throw new UnsupportedOperationException(); // Read-only bridge } @NotNull @Override public String getDocumentURI() { throw new UnsupportedOperationException(); // Not supported } @Override public void setDocumentURI(String s) { throw new UnsupportedOperationException(); // Not supported } @NotNull @Override public Node adoptNode(Node node) throws DOMException { throw new UnsupportedOperationException(); // Read-only bridge } @NotNull @Override public DOMConfiguration getDomConfig() { throw new UnsupportedOperationException(); // Not supported } @Override public void normalizeDocument() { } @NotNull @Override public Node renameNode(Node node, String s, String s2) throws DOMException { throw new UnsupportedOperationException(); // Not supported } } private static class DomElement extends DomNode implements Element { private final XmlTag myTag; @Nullable private NamedNodeMap myAttributes; private DomElement(@NotNull Document owner, @NotNull DomNode parent, @NotNull XmlTag tag) { super(owner, parent, tag); myTag = tag; } // From org.w3c.dom.Node: @NotNull @Override public String getNodeName() { return getTagName(); } @Nullable @Override public String getNodeValue() throws DOMException { return null; } @Override public short getNodeType() { return Node.ELEMENT_NODE; } @NotNull @Override public NamedNodeMap getAttributes() { if (myAttributes == null) { XmlAttribute[] attributes = myTag.getAttributes(); if (attributes.length == 0) { myAttributes = EMPTY_ATTRIBUTES; } else { myAttributes = new DomNamedNodeMap(this, attributes); } } return myAttributes; } // From org.w3c.dom.Element: @NotNull @Override public String getTagName() { return myTag.getName(); } @NotNull @Override public String getAttribute(@NotNull String name) { Node node = getAttributes().getNamedItem(name); if (node != null) { return node.getNodeValue(); } return ""; } @NotNull @Override public String getAttributeNS(@NotNull String namespace, @NotNull String name) throws DOMException { Node node = getAttributes().getNamedItemNS(namespace, name); if (node != null) { return node.getNodeValue(); } return ""; } @Nullable @Override public Attr getAttributeNodeNS(@NotNull String namespace, @NotNull String name) throws DOMException { Node node = getAttributes().getNamedItemNS(namespace, name); if (node != null) { return (Attr) node; } return null; } @Nullable @Override public Attr getAttributeNode(@NotNull String name) { Node node = getAttributes().getNamedItem(name); if (node != null) { return (Attr) node; } return null; } @Override public boolean hasAttribute(@NotNull String name) { return getAttributes().getNamedItem(name) != null; } @Override public boolean hasAttributeNS(@NotNull String namespace, @NotNull String name) throws DOMException { return getAttributes().getNamedItemNS(namespace, name) != null; } @NotNull @Override public NodeList getElementsByTagName(@NotNull String s) { NodeList childNodes = getChildNodes(); if (childNodes == EMPTY) { return EMPTY; } DomNodeList matches = new DomNodeList(); for (int i = 0, n = childNodes.getLength(); i < n; i++) { Node node = childNodes.item(i); if (s.equals(node.getNodeName())) { matches.add((DomNode) node); } } return matches; } @NotNull @Override public NodeList getElementsByTagNameNS(String s, String s2) throws DOMException { throw new UnsupportedOperationException(); // Not supported } @NotNull @Override public Attr setAttributeNode(Attr attr) throws DOMException { throw new UnsupportedOperationException(); // Read-only bridge } @NotNull @Override public Attr removeAttributeNode(Attr attr) throws DOMException { throw new UnsupportedOperationException(); // Read-only bridge } @Override public void setAttributeNS(String s, String s2, String s3) throws DOMException { throw new UnsupportedOperationException(); // Read-only bridge } @Override public void removeAttributeNS(String s, String s2) throws DOMException { throw new UnsupportedOperationException(); // Read-only bridge } @Override public void setAttribute(String s, String s2) throws DOMException { throw new UnsupportedOperationException(); // Read-only bridge } @Override public void removeAttribute(String s) throws DOMException { throw new UnsupportedOperationException(); // Read-only bridge } @NotNull @Override public Attr setAttributeNodeNS(Attr attr) throws DOMException { throw new UnsupportedOperationException(); // Read-only bridge } @NotNull @Override public TypeInfo getSchemaTypeInfo() { throw new UnsupportedOperationException(); // Not supported } @Override public void setIdAttribute(String s, boolean b) throws DOMException { throw new UnsupportedOperationException(); // Read-only bridge } @Override public void setIdAttributeNS(String s, String s2, boolean b) throws DOMException { throw new UnsupportedOperationException(); // Read-only bridge } @Override public void setIdAttributeNode(Attr attr, boolean b) throws DOMException { throw new UnsupportedOperationException(); // Read-only bridge } } private static class DomText extends DomNode implements Text { @NotNull private final XmlText myText; private DomText(@NotNull Document owner, @NotNull DomNode parent, @NotNull XmlText text) { super(owner, parent, text); myText = text; } // From org.w3c.dom.Node: @Nullable @Override public String getNodeName() { return null; } @NotNull @Override public String getNodeValue() throws DOMException { return myText.getText(); } @Override public short getNodeType() { return Node.TEXT_NODE; } // From org.w3c.dom.Text: @NotNull @Override public Text splitText(int i) throws DOMException { throw new UnsupportedOperationException(); // Read-only bridge } @Override public boolean isElementContentWhitespace() { String s = myText.getText(); for (int i = 0, n = s.length(); i < n; i++) { if (!Character.isWhitespace(s.charAt(i))) { return false; } } return true; } @NotNull @Override public String getWholeText() { throw new UnsupportedOperationException(); // Not supported } @NotNull @Override public Text replaceWholeText(String s) throws DOMException { throw new UnsupportedOperationException(); // Read-only bridge } } private static class DomComment extends DomNode implements Comment { @NotNull private final XmlComment myComment; private DomComment(@NotNull Document owner, @NotNull DomNode parent, @NotNull XmlComment comment) { super(owner, parent, comment); myComment = comment; } // From org.w3c.dom.Node: @Nullable @Override public String getNodeName() { return null; } @NotNull @Override public String getNodeValue() throws DOMException { return myComment.getText(); } @Override public short getNodeType() { return Node.COMMENT_NODE; } @NotNull @Override public String getTextContent() throws DOMException { return myComment.getText(); } } private static class DomAttr extends DomNode implements Attr { @NotNull private final DomElement myOwner; @NotNull private final XmlAttribute myAttribute; private DomAttr(@NotNull Document document, @NotNull DomElement owner, @NotNull XmlAttribute attribute) { super(document, null, attribute); myOwner = owner; myAttribute = attribute; } // From org.w3c.dom.Node: @NotNull @Override public String getNodeName() { return getName(); } @NotNull @Override public String getNodeValue() throws DOMException { return getValue(); } @Override public short getNodeType() { return Node.ATTRIBUTE_NODE; } // From org.w3c.dom.Attr: @NotNull @Override public String getName() { return myAttribute.getName(); } @Override public boolean getSpecified() { throw new UnsupportedOperationException(); // Not supported } @NotNull @Override public String getValue() { String value = myAttribute.getValue(); if (value == null) { value = ""; } return value; } @NotNull @Override public String getLocalName() { return myAttribute.getLocalName(); } @NotNull @Override public String getPrefix() { return myAttribute.getNamespacePrefix(); } @NotNull @Override public String getNamespaceURI() { return myAttribute.getNamespace(); } @Override public void setValue(String s) throws DOMException { throw new UnsupportedOperationException(); // Read-only bridge } @NotNull @Override public Element getOwnerElement() { return myOwner; } @NotNull @Override public TypeInfo getSchemaTypeInfo() { throw new UnsupportedOperationException(); // Not supported } @Override public boolean isId() { throw new UnsupportedOperationException(); // Not supported } } }