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Diffstat (limited to 'common/src/com/android/utils/PositionXmlParser.java')
| -rw-r--r-- | common/src/com/android/utils/PositionXmlParser.java | 729 |
1 files changed, 0 insertions, 729 deletions
diff --git a/common/src/com/android/utils/PositionXmlParser.java b/common/src/com/android/utils/PositionXmlParser.java deleted file mode 100644 index 73574d5..0000000 --- a/common/src/com/android/utils/PositionXmlParser.java +++ /dev/null @@ -1,729 +0,0 @@ -/* - * Copyright (C) 2011 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 com.android.utils; - -import com.android.annotations.NonNull; -import com.android.annotations.Nullable; - -import org.w3c.dom.Attr; -import org.w3c.dom.Document; -import org.w3c.dom.Element; -import org.w3c.dom.Node; -import org.w3c.dom.Text; -import org.xml.sax.Attributes; -import org.xml.sax.InputSource; -import org.xml.sax.Locator; -import org.xml.sax.SAXException; -import org.xml.sax.helpers.DefaultHandler; - -import java.io.ByteArrayOutputStream; -import java.io.IOException; -import java.io.InputStream; -import java.io.StringReader; -import java.io.UnsupportedEncodingException; -import java.util.ArrayList; -import java.util.List; -import java.util.regex.Matcher; -import java.util.regex.Pattern; - -import javax.xml.parsers.DocumentBuilder; -import javax.xml.parsers.DocumentBuilderFactory; -import javax.xml.parsers.ParserConfigurationException; -import javax.xml.parsers.SAXParser; -import javax.xml.parsers.SAXParserFactory; - -/** - * A simple DOM XML parser which can retrieve exact beginning and end offsets - * (and line and column numbers) for element nodes as well as attribute nodes. - */ -public class PositionXmlParser { - private static final String UTF_8 = "UTF-8"; //$NON-NLS-1$ - private static final String UTF_16 = "UTF_16"; //$NON-NLS-1$ - private static final String UTF_16LE = "UTF_16LE"; //$NON-NLS-1$ - private static final String CONTENT_KEY = "contents"; //$NON-NLS-1$ - private final static String POS_KEY = "offsets"; //$NON-NLS-1$ - private static final String NAMESPACE_PREFIX_FEATURE = - "http://xml.org/sax/features/namespace-prefixes"; //$NON-NLS-1$ - private static final String NAMESPACE_FEATURE = - "http://xml.org/sax/features/namespaces"; //$NON-NLS-1$ - /** See http://www.w3.org/TR/REC-xml/#NT-EncodingDecl */ - private static final Pattern ENCODING_PATTERN = - Pattern.compile("encoding=['\"](\\S*)['\"]");//$NON-NLS-1$ - - /** - * Parses the XML content from the given input stream. - * - * @param input the input stream containing the XML to be parsed - * @return the corresponding document - * @throws ParserConfigurationException if a SAX parser is not available - * @throws SAXException if the document contains a parsing error - * @throws IOException if something is seriously wrong. This should not - * happen since the input source is known to be constructed from - * a string. - */ - @Nullable - public Document parse(@NonNull InputStream input) - throws ParserConfigurationException, SAXException, IOException { - // Read in all the data - ByteArrayOutputStream out = new ByteArrayOutputStream(); - byte[] buf = new byte[1024]; - while (true) { - int r = input.read(buf); - if (r == -1) { - break; - } - out.write(buf, 0, r); - } - input.close(); - return parse(out.toByteArray()); - } - - /** - * Parses the XML content from the given byte array - * - * @param data the raw XML data (with unknown encoding) - * @return the corresponding document - * @throws ParserConfigurationException if a SAX parser is not available - * @throws SAXException if the document contains a parsing error - * @throws IOException if something is seriously wrong. This should not - * happen since the input source is known to be constructed from - * a string. - */ - @Nullable - public Document parse(@NonNull byte[] data) - throws ParserConfigurationException, SAXException, IOException { - String xml = getXmlString(data); - return parse(xml, new InputSource(new StringReader(xml)), true); - } - - /** - * Parses the given XML content. - * - * @param xml the XML string to be parsed. This must be in the correct - * encoding already. - * @return the corresponding document - * @throws ParserConfigurationException if a SAX parser is not available - * @throws SAXException if the document contains a parsing error - * @throws IOException if something is seriously wrong. This should not - * happen since the input source is known to be constructed from - * a string. - */ - @Nullable - public Document parse(@NonNull String xml) - throws ParserConfigurationException, SAXException, IOException { - return parse(xml, new InputSource(new StringReader(xml)), true); - } - - @NonNull - private Document parse(@NonNull String xml, @NonNull InputSource input, boolean checkBom) - throws ParserConfigurationException, SAXException, IOException { - try { - SAXParserFactory factory = SAXParserFactory.newInstance(); - factory.setFeature(NAMESPACE_FEATURE, true); - factory.setFeature(NAMESPACE_PREFIX_FEATURE, true); - SAXParser parser = factory.newSAXParser(); - DomBuilder handler = new DomBuilder(xml); - parser.parse(input, handler); - return handler.getDocument(); - } catch (SAXException e) { - if (checkBom && e.getMessage().contains("Content is not allowed in prolog")) { - // Byte order mark in the string? Skip it. There are many markers - // (see http://en.wikipedia.org/wiki/Byte_order_mark) so here we'll - // just skip those up to the XML prolog beginning character, < - xml = xml.replaceFirst("^([\\W]+)<","<"); //$NON-NLS-1$ //$NON-NLS-2$ - return parse(xml, new InputSource(new StringReader(xml)), false); - } - throw e; - } - } - - /** - * Returns the String corresponding to the given byte array of XML data - * (with unknown encoding). This method attempts to guess the encoding based - * on the XML prologue. - * @param data the XML data to be decoded into a string - * @return a string corresponding to the XML data - */ - public static String getXmlString(byte[] data) { - int offset = 0; - - String defaultCharset = UTF_8; - String charset = null; - // Look for the byte order mark, to see if we need to remove bytes from - // the input stream (and to determine whether files are big endian or little endian) etc - // for files which do not specify the encoding. - // See http://unicode.org/faq/utf_bom.html#BOM for more. - if (data.length > 4) { - if (data[0] == (byte)0xef && data[1] == (byte)0xbb && data[2] == (byte)0xbf) { - // UTF-8 - defaultCharset = charset = UTF_8; - offset += 3; - } else if (data[0] == (byte)0xfe && data[1] == (byte)0xff) { - // UTF-16, big-endian - defaultCharset = charset = UTF_16; - offset += 2; - } else if (data[0] == (byte)0x0 && data[1] == (byte)0x0 - && data[2] == (byte)0xfe && data[3] == (byte)0xff) { - // UTF-32, big-endian - defaultCharset = charset = "UTF_32"; //$NON-NLS-1$ - offset += 4; - } else if (data[0] == (byte)0xff && data[1] == (byte)0xfe - && data[2] == (byte)0x0 && data[3] == (byte)0x0) { - // UTF-32, little-endian. We must check for this *before* looking for - // UTF_16LE since UTF_32LE has the same prefix! - defaultCharset = charset = "UTF_32LE"; //$NON-NLS-1$ - offset += 4; - } else if (data[0] == (byte)0xff && data[1] == (byte)0xfe) { - // UTF-16, little-endian - defaultCharset = charset = UTF_16LE; - offset += 2; - } - } - int length = data.length - offset; - - // Guess encoding by searching for an encoding= entry in the first line. - // The prologue, and the encoding names, will always be in ASCII - which means - // we don't need to worry about strange character encodings for the prologue characters. - // However, one wrinkle is that the whole file may be encoded in something like UTF-16 - // where there are two bytes per character, so we can't just look for - // ['e','n','c','o','d','i','n','g'] etc in the byte array since there could be - // multiple bytes for each character. However, since again the prologue is in ASCII, - // we can just drop the zeroes. - boolean seenOddZero = false; - boolean seenEvenZero = false; - int prologueStart = -1; - for (int lineEnd = offset; lineEnd < data.length; lineEnd++) { - if (data[lineEnd] == 0) { - if ((lineEnd - offset) % 2 == 0) { - seenEvenZero = true; - } else { - seenOddZero = true; - } - } else if (data[lineEnd] == '\n' || data[lineEnd] == '\r') { - break; - } else if (data[lineEnd] == '<') { - prologueStart = lineEnd; - } else if (data[lineEnd] == '>') { - // End of prologue. Quick check to see if this is a utf-8 file since that's - // common - for (int i = lineEnd - 4; i >= 0; i--) { - if ((data[i] == 'u' || data[i] == 'U') - && (data[i + 1] == 't' || data[i + 1] == 'T') - && (data[i + 2] == 'f' || data[i + 2] == 'F') - && (data[i + 3] == '-' || data[i + 3] == '_') - && (data[i + 4] == '8') - ) { - charset = UTF_8; - break; - } - } - - if (charset == null) { - StringBuilder sb = new StringBuilder(); - for (int i = prologueStart; i <= lineEnd; i++) { - if (data[i] != 0) { - sb.append((char) data[i]); - } - } - String prologue = sb.toString(); - int encodingIndex = prologue.indexOf("encoding"); //$NON-NLS-1$ - if (encodingIndex != -1) { - Matcher matcher = ENCODING_PATTERN.matcher(prologue); - if (matcher.find(encodingIndex)) { - charset = matcher.group(1); - } - } - } - - break; - } - } - - // No prologue on the first line, and no byte order mark: Assume UTF-8/16 - if (charset == null) { - charset = seenOddZero ? UTF_16LE : seenEvenZero ? UTF_16 : UTF_8; - } - - String xml = null; - try { - xml = new String(data, offset, length, charset); - } catch (UnsupportedEncodingException e) { - try { - if (charset != defaultCharset) { - xml = new String(data, offset, length, defaultCharset); - } - } catch (UnsupportedEncodingException u) { - // Just use the default encoding below - } - } - if (xml == null) { - xml = new String(data, offset, length); - } - return xml; - } - - /** - * Returns the position for the given node. This is the start position. The - * end position can be obtained via {@link Position#getEnd()}. - * - * @param node the node to look up position for - * @return the position, or null if the node type is not supported for - * position info - */ - @Nullable - public Position getPosition(@NonNull Node node) { - return getPosition(node, -1, -1); - } - - /** - * Returns the position for the given node. This is the start position. The - * end position can be obtained via {@link Position#getEnd()}. A specific - * range within the node can be specified with the {@code start} and - * {@code end} parameters. - * - * @param node the node to look up position for - * @param start the relative offset within the node range to use as the - * starting position, inclusive, or -1 to not limit the range - * @param end the relative offset within the node range to use as the ending - * position, or -1 to not limit the range - * @return the position, or null if the node type is not supported for - * position info - */ - @Nullable - public Position getPosition(@NonNull Node node, int start, int end) { - // Look up the position information stored while parsing for the given node. - // Note however that we only store position information for elements (because - // there is no SAX callback for individual attributes). - // Therefore, this method special cases this: - // -- First, it looks at the owner element and uses its position - // information as a first approximation. - // -- Second, it uses that, as well as the original XML text, to search - // within the node range for an exact text match on the attribute name - // and if found uses that as the exact node offsets instead. - if (node instanceof Attr) { - Attr attr = (Attr) node; - Position pos = (Position) attr.getOwnerElement().getUserData(POS_KEY); - if (pos != null) { - int startOffset = pos.getOffset(); - int endOffset = pos.getEnd().getOffset(); - if (start != -1) { - startOffset += start; - if (end != -1) { - endOffset = start + end; - } - } - - // Find attribute in the text - String contents = (String) node.getOwnerDocument().getUserData(CONTENT_KEY); - if (contents == null) { - return null; - } - - // Locate the name=value attribute in the source text - // Fast string check first for the common occurrence - String name = attr.getName(); - Pattern pattern = Pattern.compile( - String.format("%1$s\\s*=\\s*[\"'].*[\"']", name)); //$NON-NLS-1$ - Matcher matcher = pattern.matcher(contents); - if (matcher.find(startOffset) && matcher.start() <= endOffset) { - int index = matcher.start(); - // Adjust the line and column to this new offset - int line = pos.getLine(); - int column = pos.getColumn(); - for (int offset = pos.getOffset(); offset < index; offset++) { - char t = contents.charAt(offset); - if (t == '\n') { - line++; - column = 0; - } else { - column++; - } - } - - Position attributePosition = createPosition(line, column, index); - // Also set end range for retrieval in getLocation - attributePosition.setEnd(createPosition(line, column + matcher.end() - index, - matcher.end())); - return attributePosition; - } else { - // No regexp match either: just fall back to element position - return pos; - } - } - } else if (node instanceof Text) { - // Position of parent element, if any - Position pos = null; - if (node.getPreviousSibling() != null) { - pos = (Position) node.getPreviousSibling().getUserData(POS_KEY); - } - if (pos == null) { - pos = (Position) node.getParentNode().getUserData(POS_KEY); - } - if (pos != null) { - // Attempt to point forward to the actual text node - int startOffset = pos.getOffset(); - int endOffset = pos.getEnd().getOffset(); - int line = pos.getLine(); - int column = pos.getColumn(); - - // Find attribute in the text - String contents = (String) node.getOwnerDocument().getUserData(CONTENT_KEY); - if (contents == null || contents.length() < endOffset) { - return null; - } - - boolean inAttribute = false; - for (int offset = startOffset; offset <= endOffset; offset++) { - char c = contents.charAt(offset); - if (c == '>' && !inAttribute) { - // Found the end of the element open tag: this is where the - // text begins. - - // Skip > - offset++; - column++; - - String text = node.getNodeValue(); - int textIndex = 0; - int textLength = text.length(); - int newLine = line; - int newColumn = column; - if (start != -1) { - textLength = Math.min(textLength, start); - for (; textIndex < textLength; textIndex++) { - char t = text.charAt(textIndex); - if (t == '\n') { - newLine++; - newColumn = 0; - } else { - newColumn++; - } - } - } else { - // Skip text whitespace prefix, if the text node contains - // non-whitespace characters - for (; textIndex < textLength; textIndex++) { - char t = text.charAt(textIndex); - if (t == '\n') { - newLine++; - newColumn = 0; - } else if (!Character.isWhitespace(t)) { - break; - } else { - newColumn++; - } - } - } - if (textIndex == text.length()) { - textIndex = 0; // Whitespace node - } else { - line = newLine; - column = newColumn; - } - - Position attributePosition = createPosition(line, column, - offset + textIndex); - // Also set end range for retrieval in getLocation - if (end != -1) { - attributePosition.setEnd(createPosition(line, column, - offset + end)); - } else { - attributePosition.setEnd(createPosition(line, column, - offset + textLength)); - } - return attributePosition; - } else if (c == '"') { - inAttribute = !inAttribute; - } else if (c == '\n') { - line++; - column = -1; // pre-subtract column added below - } - column++; - } - - return pos; - } - } - - return (Position) node.getUserData(POS_KEY); - } - - /** - * SAX parser handler which incrementally builds up a DOM document as we go - * along, and updates position information along the way. Position - * information is attached to the DOM nodes by setting user data with the - * {@link POS_KEY} key. - */ - private final class DomBuilder extends DefaultHandler { - private final String mXml; - private final Document mDocument; - private Locator mLocator; - private int mCurrentLine = 0; - private int mCurrentOffset; - private int mCurrentColumn; - private final List<Element> mStack = new ArrayList<Element>(); - private final StringBuilder mPendingText = new StringBuilder(); - - private DomBuilder(String xml) throws ParserConfigurationException { - mXml = xml; - - DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance(); - factory.setNamespaceAware(true); - factory.setValidating(false); - DocumentBuilder docBuilder = factory.newDocumentBuilder(); - mDocument = docBuilder.newDocument(); - mDocument.setUserData(CONTENT_KEY, xml, null); - } - - /** Returns the document parsed by the handler */ - Document getDocument() { - return mDocument; - } - - @Override - public void setDocumentLocator(Locator locator) { - this.mLocator = locator; - } - - @Override - public void startElement(String uri, String localName, String qName, - Attributes attributes) throws SAXException { - try { - flushText(); - Element element = mDocument.createElement(qName); - for (int i = 0; i < attributes.getLength(); i++) { - if (attributes.getURI(i) != null && attributes.getURI(i).length() > 0) { - Attr attr = mDocument.createAttributeNS(attributes.getURI(i), - attributes.getQName(i)); - attr.setValue(attributes.getValue(i)); - element.setAttributeNodeNS(attr); - assert attr.getOwnerElement() == element; - } else { - Attr attr = mDocument.createAttribute(attributes.getQName(i)); - attr.setValue(attributes.getValue(i)); - element.setAttributeNode(attr); - assert attr.getOwnerElement() == element; - } - } - - Position pos = getCurrentPosition(); - - // The starting position reported to us by SAX is really the END of the - // open tag in an element, when all the attributes have been processed. - // We have to scan backwards to find the real beginning. We'll do that - // by scanning backwards. - // -1: Make sure that when we have <foo></foo> we don't consider </foo> - // the beginning since pos.offset will typically point to the first character - // AFTER the element open tag, which could be a closing tag or a child open - // tag - - for (int offset = pos.getOffset() - 1; offset >= 0; offset--) { - char c = mXml.charAt(offset); - // < cannot appear in attribute values or anywhere else within - // an element open tag, so we know the first occurrence is the real - // element start - if (c == '<') { - // Adjust line position - int line = pos.getLine(); - for (int i = offset, n = pos.getOffset(); i < n; i++) { - if (mXml.charAt(i) == '\n') { - line--; - } - } - - // Compute new column position - int column = 0; - for (int i = offset - 1; i >= 0; i--, column++) { - if (mXml.charAt(i) == '\n') { - break; - } - } - - pos = createPosition(line, column, offset); - break; - } - } - - element.setUserData(POS_KEY, pos, null); - mStack.add(element); - } catch (Exception t) { - throw new SAXException(t); - } - } - - @Override - public void endElement(String uri, String localName, String qName) { - flushText(); - Element element = mStack.remove(mStack.size() - 1); - - Position pos = (Position) element.getUserData(POS_KEY); - assert pos != null; - pos.setEnd(getCurrentPosition()); - - if (mStack.isEmpty()) { - mDocument.appendChild(element); - } else { - Element parent = mStack.get(mStack.size() - 1); - parent.appendChild(element); - } - } - - /** - * Returns a position holder for the current position. The most - * important part of this function is to incrementally compute the - * offset as well, by counting forwards until it reaches the new line - * number and column position of the XML parser, counting characters as - * it goes along. - */ - private Position getCurrentPosition() { - int line = mLocator.getLineNumber() - 1; - int column = mLocator.getColumnNumber() - 1; - - // Compute offset incrementally now that we have the new line and column - // numbers - int xmlLength = mXml.length(); - while (mCurrentLine < line && mCurrentOffset < xmlLength) { - char c = mXml.charAt(mCurrentOffset); - if (c == '\r' && mCurrentOffset < xmlLength - 1) { - if (mXml.charAt(mCurrentOffset + 1) != '\n') { - mCurrentLine++; - mCurrentColumn = 0; - } - } else if (c == '\n') { - mCurrentLine++; - mCurrentColumn = 0; - } else { - mCurrentColumn++; - } - mCurrentOffset++; - } - - mCurrentOffset += column - mCurrentColumn; - if (mCurrentOffset >= xmlLength) { - // The parser sometimes passes wrong column numbers at the - // end of the file: Ensure that the offset remains valid. - mCurrentOffset = xmlLength; - } - mCurrentColumn = column; - - return createPosition(mCurrentLine, mCurrentColumn, mCurrentOffset); - } - - @Override - public void characters(char c[], int start, int length) throws SAXException { - mPendingText.append(c, start, length); - } - - private void flushText() { - if (mPendingText.length() > 0 && !mStack.isEmpty()) { - Element element = mStack.get(mStack.size() - 1); - Node textNode = mDocument.createTextNode(mPendingText.toString()); - element.appendChild(textNode); - mPendingText.setLength(0); - } - } - } - - /** - * Creates a position while constructing the DOM document. This method - * allows a subclass to create a custom implementation of the position - * class. - * - * @param line the line number for the position - * @param column the column number for the position - * @param offset the character offset - * @return a new position - */ - @NonNull - protected Position createPosition(int line, int column, int offset) { - return new DefaultPosition(line, column, offset); - } - - protected interface Position { - /** - * Linked position: for a begin position this will point to the - * corresponding end position. For an end position this will be null. - * - * @return the end position, or null - */ - @Nullable - public Position getEnd(); - - /** - * Linked position: for a begin position this will point to the - * corresponding end position. For an end position this will be null. - * - * @param end the end position - */ - public void setEnd(@NonNull Position end); - - /** @return the line number, 0-based */ - public int getLine(); - - /** @return the offset number, 0-based */ - public int getOffset(); - - /** @return the column number, 0-based, and -1 if the column number if not known */ - public int getColumn(); - } - - protected static class DefaultPosition implements Position { - /** The line number (0-based where the first line is line 0) */ - private final int mLine; - private final int mColumn; - private final int mOffset; - private Position mEnd; - - /** - * Creates a new {@link Position} - * - * @param line the 0-based line number, or -1 if unknown - * @param column the 0-based column number, or -1 if unknown - * @param offset the offset, or -1 if unknown - */ - public DefaultPosition(int line, int column, int offset) { - this.mLine = line; - this.mColumn = column; - this.mOffset = offset; - } - - @Override - public int getLine() { - return mLine; - } - - @Override - public int getOffset() { - return mOffset; - } - - @Override - public int getColumn() { - return mColumn; - } - - @Override - public Position getEnd() { - return mEnd; - } - - @Override - public void setEnd(@NonNull Position end) { - mEnd = end; - } - } -} |